Showing posts with label Science. Show all posts
Showing posts with label Science. Show all posts

06 March 2024

X-ray photoelectron spectroscopy (XPS)

Working principle & Instrumentation 



XPS instrumentation
XPS instrumentation 


XPS (photoelectron spectroscopy) is a surface-sensitive technique used to analyze the elemental composition, chemical state, and electronic state of elements on the surface of a material.

In Xps photoelectrons emitted from material as function of their binding energy in the sample, allowing for the identification of elements and their chemical states. It is highly sensitive to the top few nanometers of a material, making it valuable for surface analysis. XPS provide more athentic data than EDX.

XPS instrument typically consists of an X-ray source,usually Mg kα hv=1253.6ev line width = 0.7ev Al kα hv=1486.6ev line width=0.85ev, an hemisphere electronenergy analyzer outer negative and inner positve lining to intact electron in center, and a detector. X-rays are used to excite electrons from the sample, and the emitted photoelectrons are analyzed based on their kinetic energy (KE). XPS involves irradiating a material's surface with X-rays, which causes the emission of photoelectrons from the inner electron shells of atoms. The kinetic energy and number of emitted electrons are measured through detecter or analyser to determine the binding energy (BE) and abundance of each element providing information about the material's elemental composition electronic structure density and chemical states. Xps measures mostly top 10nm and provide surface information. Total energy of the system is hv=KV+BE+Φ si is work function, Xps can be used in line profiling of the elemental composition across the surface or 

in depth profiling when pair with ion beam itching. 


Sample Preparation Samples should be clean free of contamination. Conductive samples are preferred to avoid charging effects. Additionally, samples may need to be rotated during analysis to ensure a representative surface is probed.


Results Interpretation XPS spectra show peaks corresponding to different elements, the position of these peaks provides information about the chemical state of the elements. The intensity of the peaks is proportional to the elemental concentration. Different peaks are making in single graph shows oxidation state known as deconvolution, when one peak get difused new one is start making this 

type of peaks called satellite peaks indicate the change in the oxidation state.



XPS spectrum
XPS spectrum 




X-ray Diffraction (XRD)

Working principle & Instrumentation 




XRD instrumentation 



XRD (X-ray Diffraction) is versatile nondistructive technique used to analyze the crystallographic structure of materials by measuring the diffraction pattern of X-rays as they interact with a crystalline 

sample.

XRD provides information about crystal structure, lattice parameters, phase composition, and preferred orientation of crystallites in a sample. Many materials are made up of tiny crystallites the chemical composition and structural type of these crystals is called their phase materials can be single phase or multiphase mixture and may conatin crystalline and non cryastalline components. In an X-ray diffracto meter different crystalline phases gives different diffraction patterns. Phase identification can be perform by comparing X-ray diffraction patteren obtained from unknown samples to patterens inreference data base. In XRD atoms of the sample donot absorb X-ray at all they just reflect them .if we did not get any peak in the material its mean the material 

is amrophous other vice it will be crystalline.

The XRD instrument consists of an X-ray tube, a sample holder, a crystal monochromator or a diffracting crystal, and a detector. The instrument used to maintain the angle and rotate the sample is termed a goniometer. The X-ray beam interacts (constractive interference) with the sample and the diffracted X-rays are detected to generate a diffraction pattern. The wavelegth of X-ray used is of the same order of magnitude of the distance between the atom in crystalline lattice. This gives rise to a diffraction pattern that can be analysied by number of ways usually sherrer equation D=Kλ/βcosϴ is used for crystalline size determination D=crystallite size K=0.9 (scherrer constant) λ= 0.15406nm (wave length of X-ray source) β=FWHM(in radians) ϴ= peak position (in radians) Bragges law nλ=2dsineϴ d= nλ/2sineϴ d= interplaner spacing or d spacing (in Ǻ) is used for mesurement of interplaner spacing or d spacing.


Sample Preparation Samples should be finely powdered and homogenously dispersed to ensure representative results. Amorphous materials may not produce diffraction patterns, as XRD is most effective for crystalline samples.


Results Interpretation XRD results are typically presented as a diffraction pattern, where peaks correspond to specific crystallographic planes. The position and intensity of these peaks provide information about the crystal structure and phase composition of the materialPeak width is inversly proportion to crystal size.



XRD graph
XRD graph 




05 March 2024

Fourier Transform Infrared Spectroscopy (FTIR)

Working principle & Instrumentation 



FTIR instrumentation
 FTIR instrumentation 


FTIR (Fourier Transform Infrared Spectroscopy) is analytical technique for determining functional group and crystal orientations. Their nature may be of organic or inorganic. FTIR contain IR source to produce IR radiation Interferometer (Michelson interferometer) which contain beam splitter, stationary mirror and moving mirror. Which split the beam into two beams two possiblities are,one is destructive interference called OPD (optical path difference) height and valley (crest and trough) of IR not match in beam spliter when it rejoin and cancel the effect of each other.

ZPD (zero path difference ) height and valley (crest and trough) of IR beams match is known as constructive interferences which gives results when fall on sample.

Basic principle is that electrons between different elements absorbed IR radiations at different frequencies matching to it in the range in FTIR this interaction (measures absorbance or emittence) These signals are decoded by applying techniques Fourier transformation to produced spectra usually in the mid-IR region corresponds to wavenumbers 4000 to 400cm-1 .


Sample prepration Samples for FTIR analysis must be prepared in a form suitable for transmission or reflection of infrared light. This often involves creating thin films, in disc or KBr wafer method by using potassium bromide (KBr) 3:1 ratio (3% KBR : 1% sample) mix well with each other grinding, mashing then place it in pressing disc press through hydraulic press applying pressure of 8 to 10 mega pascal to attain very thin crackless pellet place it in analyzer chamber to analyze. In direct method Liquids can analyize directly droping few drops on analyzer The goal is to present a uniform and representative sample.


Results interpretation FTIR spectra display peaks at specific wavenumbers corresponding to molecular vibrations. Peaks indicate the presence of certain functional groups or bonds. The intensity and position of these peaks provide information about the concentration and type of chemical bonds in the sample. 

Upto 4000cm-1 to 1500cm-1 is Known as functional group region 1500cm-1 to 400cm-1 known as finger print region specific for each material, match the spectra with IR data base to identify the functional group and materials.



FTIR spectra
FTIR spectra





05 February 2024

Surface Area Analyzer (SSA)

Working principle & Instrumentation 




SAA instrumentation
SAA instrumentation 



The SSA (Surface Area Analyzer) is used to measure the specific surface area of a material, providing information about its porosity and the extent of available surface for chemical interactions. 

SAA quantifies the surface area by adsorbing gas molecules onto the material's surface and measuring the amount adsorbed. The data is then used to calculate the specific surface area. SAA typically consists of a degas system to remove adsorbed gases from the material, a sample cell where adsorption occurs, and a detection system to measure the adsorbed gas quantity. Instruments may use various inert and some other adsorptive gases like nitrogen. Principle is the gas adsorption onto the sample's surface. The amount of gas adsorbed is directly related to the surface area. The BET (Brunauer, Emmett, Teller) theory is commonly employed, which assumes the formation of a monolayer (as Langmuir theory) or multilayer of gas molecules on the surface. By analyzing the gas adsorption isotherm, the surface area of the material can determined accurately.

It is essential for characterizing materials with porous structures, like catalysts, adsorbents, and powders. It provides valuable information for researchers and industries involved in areas such as catalysis,  material science, environmental science etc. Pore volume and pore area distributions in the mesopore and macropore ranges by the BJH (Barrett, Joyner, Halenda) method of gas adsorption and desorption using a variety of thickness equations including a user-defined, standard isotherm (graph of gas adsorpition vs relative pressure).


Sample Preparation Samples need to be prepared by degassing to remove any previously adsorbed gases or contaminants. This is crucial for accurate measurements. Samples are often finely powdered or have a high surface area, such as porous materials like zeolites or activated carbon.


Results interpretation The specific surface area is determined by analyzing the quantity of gas adsorbed at various pressures. A plot of adsorption isotherm (adsorbed gas versus pressure) is created. Specific surface area is calculated using models such as the BET (Brunauer, Emmett, and Teller) equation systematically and provide BET isotherm gas adsorption graph. The BET theory is commonly employed, which assumes the formation of a monolayer (as langmuir theory) and can be multilayer of gas molecules on the surface.


SAA graph
SAA graph





04 February 2024

Pore Size Distribution (PSD)

Working principle & Instrumentation 



PSD instrumentation
PSD instrumentation 

 


Pore size distribution analysis is used to determine the range of pore sizes within a material. This information is crucial for understanding the material's properties, especially in fields like material science, catalysis, and filtration.

PSD provides data on the distribution of pore sizes, indicating the variety of pore dimensions within a material. This information is vital for assessing how easily fluids can move through the material and its suitability for specific applications.

Various techniques are used for PSD analysis, including gas adsorption methods (often with instruments like BET analyzers (works on the BET theory principle ),

The BET (Brunauer, Emmett, and Teller) theory is commonly employed, which assumes the formation of a monolayer (as Langmuir theory) or multilayer of gas molecules on the surface. 

Mercury intrusion porosimetry (pore structure diameter volume etc), and nuclear magnetic resonance (NMR) methods. Each technique offers different insights into pore size distribution.

The principle varies based on the technique employed. In gas adsorption methods like BET, the principle involves the adsorption of gas molecules onto the surface of the material. In mercury intrusion porosimetry, mercury is forced 

into the pores, and the intrusion pressure is related to pore size. NMR methods rely on the interactions between nuclear spins and the material's structure to infer pore size distribution. Each method exploits different physical principles to 

provide information about the material's porosity.


Sample Preparation Sample preparation depends on the technique used. For gas adsorption methods, the material is typically degassed to remove adsorbed gases. In mercury intrusion porosimetry, the sample is impregnated with mercury. NMR methods require specific sample handling for accurate results.


Results interpretation PSD results are often presented as a plot showing the 

percentage of pores within specified size ranges. The shape of the distribution curve provides insights into the homogeneity of the pore size within the material.


PSD graph
PSD graph 




24 December 2023

Point of Zero Charge (PZC)

Working principle & Instrumentation  




PZC instrumentation
PZC instrumentation 



The Point of Zero Charge (PZC or pH

PZC) is a characteristic of a material's surface at which the material carries no net electrical charge. It is a critical parameter in understanding the surface charge behavior of materials, particularly in the context of colloidal systems and adsorption phenomena. It is that value of PH where surface attain neutrality.

The PZC is related to the protonation or deprotonation of functional groups on the material's surface. At the PZC, the concentrations of positively and negatively charged sites are equal, surface attain neutrality, Experimental methods involve determining the pH at which the material exhibits no net charge. This is often done by measuring the zeta potential or by titrating the material. with an acid or a base and monitoring the surface charge In salt addition method first Prepared 600ml 0.1M stalk solution of Sodium nitrate, take 40ml of this solution in fourteen different Erlenmeyer or conanical flasks one by one set the different pH value (1 to 14) of the solution with either adding acid or base drop vice through droper carefully Nitric acid (0.1 M) or Sodium hydroxide (0.1 M) by using a pH meter addjust different pH value from (1 to 14) has been set these are the initial pH (pHi) values then in each flask add desirable composite or material whose pzc want to be determin placed all these flask in orbital shaker and shake at speed of 150 rpm on the orbital shaker at room temperature for 24 hours or set the parameters of your own choice according to sample requirement. After equlibrium filter the contents, and record the pH of beaker containg the filtrate known as final pH (pHf) then find the change in pH by ΔpH=pHi _ pHf then draw the graph against ΔpH and pHi the line intersect or coside on the zero is its PZC.


Sample Preparation Sample preparation depends on the technique used in salt addition method Care fully salt solution prepared 0.1 M adjust their pH (1 to 14 by adding acidc or basic solution drope vice in it) Disperse the cleaned material in each of the prepared solutions. This could involve mixing the material with the solution and allowing it to equilibrate.


Results interpretation The pH below the PZC, the surface is positively charged, and above the PZC, it becomes negatively charged. PZC is crucial for predicting the adsorption behavior of ions and molecules onto a material's surfaces.


Figure PZC graph

Figure PZC graph 




23 December 2023

Thermogravimetry Analysis (TGA)

Working principle & Instrumentation 




Figure TGA instrumentation

TGA instrumentation 




Thermal analysis are Techniques in which a physical property of a substance is measured as a function of temperature whilst the substance is subjected to a controlled temperature programme certain techniques lie in this here we discuse TGA and DTA in detail.

Thermogravimetry (TGA) is a technique in which the mass of a substance is measured as a function of temperature while the substance is subjected to a controlled temperature programme. The record is the thermogravimetric or TG curve or graph the mass should be plotted on the ordinate decreasing downwards and temperature (T) or time (t) on the abscissa increasing from left to right.

A thermobalance is used for weighing a sample continuously while it is being heated (in a given enivornement, air, N2, CO2, He, Ar, etc ) or cooled. The heating rate is the rate of temperature increase, which is customarily quoted in degrees per minute (on the Celsius or Kelvin scales). The heating or cooling rate is said to be constant when the temperature/time curve is linear. 

The initial temperature, Ti, is thattemperature (on the Celsius or Kelvin scale) at which the cumulative-mass change reaches a magnitude that the thermobalance can detect. The final temperature, Tf, is that temperature (on the Celsius or Kelvin scale) at which the cumulative mass change reaches a maximum. The reaction interval is the temperature difference between Tf and Ti as defined above. TG measures changes in sample mass, indicating processes such as decomposition, oxidation, or phase transitions. DTA can perform with it for physical property of substance is measured as a function of temperature at controlled temperature programme.


Sample Preparation Samples are usually finely ground and placed in a sample holder. It's crucial to have a representative sample and to account for factors like sample size and packing density, as they influence the thermal behavior.


Results interpretation In TG, weight loss or gain is observed as a function of temperature, providing information about processes like decomposition or oxidation. Plateau A plateau is that part of the TG curve where the mass is essentially constant. And decline line in grapgh shows decrease in mass as function of temperature.



Figure TGA graph

TGA graph 





Differential Thermal Analysis (DTA)

Working principle & Instrumentation 



DTA instrumentation
DTA instrumentation 


 

Thermal analysis are Techniques in which a physical property of a substance is measured as a function of temperature whilst the substance is subjected to a controlled temperature programme certain techniques lie in this here we discuse DTA in deatail.

DTA mesures the temperature difference between the sample and refrence materila as they both undergo the same temperature programme. The record is the differential thermal or DTA curve or thermogram; the temperature difference (∆T) should be plotted on the ordinate with endothermic reactions downwards and temperature or time on the abscissa increasing from left to right. The term quantitative differential thermal analysis (quantitative DTA) covers those uses of DTA where the equipment is designed to produce quantitative results in terms of energy and/or any other physical parameter.


Sample Preparation Samples are usually finely ground and placed in a sample holder. It's crucial to have a representative sample and to account for factors like sample size and packing density, as they influence the thermal behavior.


Results interpretation The base line corresponds to the portion or portions of the DTA curve, thermogram or thermograph for which ∆T is approximately zero. 

A peak is that portion of the DTA curve which departs from and subsequently returns to the base line. 

Endothermic peaks or endotherm, is a peak where the temperature of the sample falls below that of the reference material, i.e., ∆T is negative. 

Exothermic peaks or exotherm, is a peak where the temperature of the sample rises above that of the reference material, i.e., ∆T is positive. 

Peak width is the time or temperature interval between the points of departure from and return to the base line. There are several ways of interpolating the base

line as peak height peak width , peak area etc.



DTA thermogram
DTA thermogram 




20 May 2023

Sperm donation

 



Sperm donation



Sperm donation Process



Sperm donation is the provision by a man of his sperm with the intention that it be used in the artificial insemination or other "fertility treatment" of one or more women who are not his sexual partners in order that they may become pregnant by him. Where pregnancies go to full term, the sperm donor will be the biological father of every baby born from his donations.

The man is known as a sperm donor and the sperm he provides is known as "donor sperm" because the intention is that the man will give up all legal rights to any child produced from his sperm, and will not be the legal father.


Egg donation




Egg donation



Egg donation Process



Egg donation is the process by which a woman donates eggs to enable another woman to conceive as part of an assisted reproduction treatment or for biomedical research. For assisted reproduction purposes, egg donation typically involves in vitro fertilization technology, with the eggs being fertilized in the laboratory; more rarely, unfertilized eggs may be frozen and stored for later use. Egg donation is a third party reproduction as part of assisted reproductive technology.


Reasons for Egg donation 

A need for egg donation may arise for a number of reasons. Infertile couples may resort to egg donation when the female partner cannot have genetic children because her own eggs cannot generate a viable pregnancy, or because they could generate a viable pregnancy but the chances are so low that it is not advisable or financially feasible to do IVF with her own eggs. This situation is often, but not always based on advanced reproductive age. It can also be due to early onset of menopause, which can occur as early as their 20s. In addition, some women are born without ovaries, while some women's reproductive organs have been damaged or surgically removed due to disease or other circumstances. Another indication would be a genetic disorder on part of the woman that either renders her infertile or would be dangerous for any offspring, problems that can be circumvented by using eggs from another woman. Many women have none of these issues, but continue to be unsuccessful using their own eggs—in other words, they have undiagnosed infertility—and thus turn to donor eggs or donor embryos. As stated above, egg donation is also helpful for gay male couples using surrogacy .


Procedure

After being recruited and screened, an egg donor must give informed consent before participating in the IVF process. Once the egg donor is recruited, she undergoes IVF stimulation therapy, followed by the egg retrieval procedure. After retrieval, the ova are fertilized by the sperm of the male partner (or sperm donor) in the laboratory, and, after several days, the best resulting embryo(s) is/are placed in the uterus of the recipient, whose uterine lining has been appropriately prepared for embryo transfer beforehand. If a large number of viable embryos are generated, they can be cryopreserved for future implantation attempts. The recipient is usually, but not always, the person who requested the service and then will carry and deliver the pregnancy and keep the baby.


Medical Examination of donar,s

Before any intensive medical, psychological, or genetic testing is done on a donor,their physical and temperamental resemblance to the recipient woman). This is due to the fact that all of the mentioned examinations are expensive and the agencies must first confirm that a match is possible or guaranteed before investing in the process.

The donor is then required to undergo a thorough medical examination, including a pelvic exam, a blood test to evaluate hormone levels(notably Anti-Müllerian hormone), infection risk, Rh factor, blood type, and drug use, and an ultrasound to examine her ovaries, uterus and other pelvic organs. A family history of approximately the past three generations is also required, meaning that adoptees are usually not accepted because of the lack of past health knowledge. Genetic testing is also usually done on donors to ensure that they do not carry mutations (e.g., cystic fibrosis) that could harm the resulting children; however, not all clinics automatically perform such testing and thus recipients must clarify with their clinics whether such testing will be done.


Donation cycle

Once the screening is complete and a legal contract signed, the donor will begin the donation cycle, which typically takes between three and six weeks. An egg retrieval procedure comprises both the Egg Donor's Cycle and the Recipient's Cycle. Birth control pills are administered during the first few weeks of the egg donation process to synchronize the donor's cycle with the recipient's, followed by a series of injections which halt the normal functioning of the donor's ovaries. These injections may be self-administered on a daily basis for a period of one to three weeks. Next, follicle-stimulating hormones (FSH) are given to the donor to stimulate egg production and increases the number of mature eggs produced by the ovaries. Throughout the cycle the donor is monitored often by a physician using blood tests and ultrasound exams to determine the donor's reaction to the hormones and the progress of follicle growth.

Once the doctor decides the follicles are mature, they will establish the date and time for the egg retrieval procedure. Approximately 36 hours before retrieval, the donor must administer one last injection of HCG hormone to ensure that her eggs are ready to be harvested. This hormone will produce a LH hormone concentration peak and induce follicular development. The oocytes are then retrieved from developed follicles via ovarian punction. This extraction must occur before ovulation, as oocytes are too small to be identified once they leave the follicle, and if the appropriate time window is missed the donation cycle will need to be repeated.

The egg retrieval itself is a minimally invasive surgical procedure lasting 20–30 minutes, performed under sedation by an anesthetist, to ensure the donor is kept completely pain free. Egg donors may also be advised to take a pain-relieving medicine one hour before egg collection, to ensure minimum discomfort after the procedure. A small ultrasound-guided needle is inserted through the vagina to aspirate the follicles in both ovaries, which extracts the eggs. After resting in a recovery room for an hour or two, the donor is released. Most donors resume regular activities by the next day.


History

The first child born from egg donation was reported in Australia in 1983. In July 1983, a clinic in Southern California reported a pregnancy using egg donation, which led to the birth of the first American child born from egg donation on 3 February 1984. This procedure was performed at the Harbor UCLA Medical Center and the University of California at Los Angeles School of Medicine. In the procedure, which is no longer used today, a fertilized egg that was just beginning to develop was transferred from one woman in whom it had been conceived by artificial insemination to another woman who gave birth to the infant 38 weeks later. The sperm used in the artificial insemination came from the husband of the woman who bore the baby.

Before this development, thousands of infertile women, single men and same-sex male couples had adoption as the only path to parenthood. The donation of human oocytes and embryos has since become a common practice similar to other donations such as blood and major organ donations. The practice of egg donation has sparked media attention and public debate, and has had a substantial impact on the field of reproductive medicine.

This scientific breakthrough changed the possibilities for those who were unable to have children due to female infertility and for those at high risk for passing on hereditary disorders. As IVF developed, the procedures used in egg donation developed in parallel: the egg donor's eggs are now harvested from her ovaries in an outpatient surgical procedure and fertilized in the laboratory, the same procedure used on IVF patients. The resulting embryo or embryos are then transferred into the intended mother instead of into the woman who provided the egg. Donor oocytes thus give women a mechanism to become pregnant and give birth to a child that will be their biological child, but not their genetic child. In cases where the recipient's womb is absent or unable to carry a pregnancy, or in cases involving gay male couples, the embryos are implanted into a gestational surrogate, who carries the embryo to term, per an agreement with the future parents. The combination of egg donation and surrogacy has enabled gay men, including singer Elton John and his partner, to have biological children. Oocyte and embryo donation now account for approximately 18% of in vitro fertilization recorded births in the US.

This work established the technical foundation and legal-ethical framework surrounding the clinical use of human oocyte and embryo donation, a mainstream clinical practice, which has evolved over the past few decades.





Egg Freezing or Oocyte Cryopreservation



Egg Freezing or Oocyte Cryopreservation




Egg Freezing Process




Egg freezing is a method of preserving a woman’s fertility so she can try and have children at a later date. 

Firstly, you’ll need to be tested for any infectious diseases like HIV and hepatitis. This has no bearing on whether you can freeze your eggs or not, but is to ensure that affected egg samples are stored separately to prevent contamination of other samples.

You'll then start the IVF process, which usually takes around two to three weeks to complete. Normally this will involve taking drugs to boost your egg production and help the eggs mature. When they’re ready, they’ll be collected whilst you’re under general anaesthetic or sedation.

At this point, instead of mixing the eggs with sperm (as in conventional IVF) a cryoprotectant (freezing solution) will be added to protect the eggs. The eggs will then be frozen either by cooling them slowly or by vitrification (fast freezing) and stored in tanks of liquid nitrogen. Latest statistics show that vitrification is more successful than the slow cooling method.

Most patients under 38 years of age will have on around 7-14 eggs collected, although this isn’t always possible for patients with low ovarian reserves (low numbers of eggs). When you want to use them, the eggs will be thawed and those that have survived intact will be injected with your partner’s or donor’s sperm.


Preparation 

Before the egg-freezing process begins, a doctor will take a comprehensive medical history with a focus on fertility, assess the regularity of the menstrual cycle, and perform a range of blood tests to assess hormone levels.

A woman’s ovaries usually release one egg per month. When fewer eggs are available for freezing, the chances of a successful pregnancy are lower.

In order to maximize the number of available eggs, a woman will undergo hormone treatment to stimulate the production of more eggs. This treatment normally requires a woman to inject herself with hormones at home between one and three times a day.

Most women will also take birth control pills for at least a month before receiving the hormone injections. This suppresses the natural cycle and increases the effectiveness of the hormones.

The number and type of hormones vary. Treatment will normally include:

around 2 weeks of injections with follicle-stimulating hormone (FSH) and luteinizing hormone (LH), which encourage the ovaries to produce more eggsan injection of gonadotropin-releasing hormone (GnRH) about halfway through the cycle, which prevents ovulation from taking place too early in the cyclean injection of human chorionic gonadotropin (hCG) to trigger ovulation.

A doctor will perform regular blood tests to monitor the effects of hormone treatments. The woman will also have at least one ultrasound to detect ovulation and to assess egg development.


Procedure

The steps of egg freezing or oocyte cryopreservation are:

Ovarian stimulation: begins with transvaginal ultrasound examination and blood tests to determine the number of oocytes and ovarian function and administering ovarian-stimulation medication for 9-12 days. The doses required vary among patients, depending on their ovarian functions. Follow-up ultrasounds will see whether the egg size and number meet the specifications. If it is, administering another medication will help the eggs mature.

Egg retrieval: is performed by transvaginal ultrasound-guided needle aspiration and suction to harvest the eggs from the follicles. 

Simply The doctor inserts a needle into the ovarian follicles to retrieve the eggs after they ripen.

It is a minor procedure performed under IV sedation given by an anesthesiologist. Patients must not eat or drink for at least 8 hours before the procedure. Egg retrieval takes around 30-45 minutes, depending on the number of retrievable oocytes.

The doctor will normally use ultrasound to guide the procedure. However, if the eggs are not visible during ultrasound imaging, the doctor may perform abdominal surgery to remove them.

With this more invasive approach, the doctor makes a small incision in the abdomen under sedation and pain medication and inserts a needle to extract the egg.

An embryologist selects healthy eggs for freezing: Once the doctor has retrieved the egg, freezing will need to take place as soon as possible. However, the eggs are full of water, which can become damaging ice crystals if freezing occurs immediately.

To prevent this, the doctor injects a special solution into the eggs before freezing them.

In the future, when the woman is ready to use her eggs, she will undergo in vitro fertilization (IVF).

With IVF, a fertility specialist fertilizes the egg in a lab, using sperm from either the woman’s partner or from a donor.

If the procedure works, the egg and sperm develop into an embryo that undergoes implantation in the woman’s uterus a few days later. Most fertility clinics try to grow several embryos at once to increase the chances of a successful pregnancy.


Advantages of egg freezing or oocyte cryopreservation

  • Suitable for women who want to freeze their eggs for future in vitro fertilization when they are ready for pregnancy.
  • Suitable for those who want to freeze their eggs before chemotherapy or radiotherapy, which can damage the ovaries.
  • Suitable for those with genetic disorders causing premature ovarian failure, or those with ovarian dysfunction such as chocolate cyst.
  • To treat infertility with IVF. If the male partner has ejaculation problems or produces no sperm on the day of egg retrieval, freeze the eggs for future use.
  • To freeze the eggs for donation.

Reasons that women freeze their eggs

Some major reasons

Career and educational plans: Women who wish to pursue advanced degrees or demanding careers may freeze their eggs when they are young to ensure access to healthy eggs later on.

Personal circumstances: Women who want to have a child with a partner but have not yet found one may freeze their eggs for future use.

Cancer: Chemotherapy and other cancer treatments typically interfere with and sometimes end fertility. Reproductive cancers might lead to the removal of a woman’s ovaries.

Egg freezing might help reduce the impact of some cancer treatments on fertility.

Infections, organ failure, and other health concerns: A wide range of health problems can harm egg quality and fertility, such as endometriosis, a condition that causes uterine tissue to grow outside of the womb.

Freezing eggs offers hope to women who are receiving treatment for a serious illness that may reduce fertility.


WHY FREEZE YOUR EGGS BEFORE YOUR 30s

Younger women have significantly higher success rates than older women when freezing eggs.

Women who wish to undergo egg freezing should do so as early as possible.

An optimal time to freeze your eggs is in your 20s and early 30s, while you have a higher ovarian reserve (the number of eggs in your ovaries) and healthier eggs. Sometimes the future seems a long way off. While you focus on your career, finding the right partner or addressing medical issues, time can run out.

Most clinics work with women who are under 40 years old. Some clinics place restrictions on women who are 40–49 years of age. Few will allow women over the age of 45 years to freeze their eggs.

Whatever your reasons, if you think you might want a family someday but aren’t ready right now or in the near future, egg freezing gives you the choice to decide when the time is right for you.

Successful Fertilization Rates of Frozen Eggs

The success rate depends on the quantity and quality of the eggs and their ages. Usually, the survival rate of frozen-thawed oocytes is around 80-90%. The success rate of fertilization is 70-80%. After successful fertilization, the embryo will let growing for another five days, reaching the blastocyst stage, which is suitable for implantation. The success rate of development to the blastocyst stage is around 60%.


How longs eggs can be stored

Recent legislation changes in the UK mean that the amount of time that you can store frozen eggs has been extended from 10 to 55 years.

Although you can now store eggs for later use up to a maximum of 55 years from when they are first placed in storage, you will need to renew your consent every ten years. You will need to fill out a consent form, and if you need to renew your consent, you will be kept up to date by the clinic where your eggs are stored. For this reason, you need to keep your contact details up to date with the clinic, or there’s a risk of your eggs being taken out of storage and disposed of.

From a technical perspective, frozen eggs can be stored for an indefinite amount of time. Once eggs are frozen, are stored in liquid nitrogen at a very low temperature, which means that they do not age or deteriorate over time. This allows them to be stored for long periods of time without losing their viability.

You shouldn’t have to pay the entire egg freezing storage cost up front, but you will need to continue to pay for egg storage over time or your clinic might dispose of eggs where storage has not been paid for. 


Cost of egg freezing

The cost of egg freezing can vary depending on a number of factors, including where you live, the clinic you choose, and the reason you are freezing your eggs. You can only freeze eggs at the NHS’s expense if you need to do so for medical reasons. On the NHS, freezing eggs for social reasons will not be paid for and you will need to fund this yourself.

Costs will include an initial consultation, hormone treatments to stimulate egg production, the egg retrieval procedure, and the cost of freezing and storing the eggs. It’s important to discuss the costs with your doctor and the clinic you choose in advance to make sure that you are aware of all the costs that are involved, and to get a better idea of what to expect.


Freeze and share programme

Most of the countries have Freeze and share programmes like UK .

Freeze and Share makes it possible for you to freeze your eggs for free because you keep half the eggs retrieve for your own later use and make the other half available to give another family the chance to have a baby of their own.

Offer of free freezing eggs may be for time limit like mostly two years to five years.





Surrogacy

 


Surrogacy



Surrogacy is an arrangement, often supported by a legal agreement, whereby a woman agrees to delivery/labour or Carrier on behalf of another couple or person, who will become the child's parent(s) after birth. People may seek a surrogacy arrangement when a couple do not wish to carry a pregnancy themselves, when pregnancy is medically impossible, when pregnancy risks are dangerous for the intended mother, or when a single man or a male couple wish to have a child.


15 May 2023

Cultured meat (Lab grown meat)




Cultured meat (Lab grown meat)




Cultured meat (also known by other names like lab grown meat , artificial meat is occasionally used) is meat produced by culturing animal cells in vitro. It is a form of cellular agriculture.
Lab-grown meat or Cultured meat is a genetically engineered product that uses biotechnology. 

Cultured meat is produced using tissue engineering techniques pioneered in regenerative medicine. Jason Matheny popularized the concept in the early 2000s after he co-authored a paper on cultured meat production and created New Harvest, the world's first nonprofit organization dedicated to in-vitro meat research.

Cultured meat has the potential to address the environmental impact of meat production, animal welfare, food security and human health, in addition to its potential mitigation of climate change.

In 2013, Mark Post created a hamburger patty made from tissue grown outside of an animal. Since then, other cultured meat prototypes have gained media attention: SuperMeat opened a farm-to-fork restaurant called "The Chicken" in Tel Aviv to test consumer reaction to its "Chicken" burger, while the "world's first commercial sale of cell-cultured meat" occurred in December 2020 at Singapore restaurant 1880, where cultured meat manufactured by US firm Eat Just was sold.

While most efforts focus on common meats such as pork, beef, and chicken which constitute the bulk of consumption in developed countries, companies such as Orbillion Bio focused on high end or unusual meats including elk, lamb, bison, and Wagyu beef. Avant Meats brought cultured grouper to market in 2021, while other companies have pursued different species of fish and other seafood.

The production process is constantly evolving, driven by companies and research institutions. The applications for cultured meat led to ethical, health, environmental, cultural, and economic discussions. Data published by the non-governmental organization Good Food Institute found that in 2021 cultivated meat companies attracted $140 million in Europe. Cultured meat is mass-produced in Israel. The first restaurant to serve cultured meat opened in Singapore in 2021.


Nomenclature 

Besides cultured meat, the terms healthy meat, slaughter-free meat, in vitro meat, vat-grown meat, lab-grown meat,cell-based meat, clean meat, cultivated meat and synthetic meat have been used to describe the product. Artificial meat is occasionally used, although that specific term has multiple definitions.


Why was need felt for cultured meat

70 billion land animals, and possibly trillions of marine animals, are killed for human consumption each year. A majority of these animals are raised in factory farms, where they experience brutal forms of abuse in severely overcrowded and putrid conditions for the entirety of their short lives.

Major meat producers often defend factory farming as the most efficient way to meet the global demand for meat. But evidence shows that these facilities are disastrous for the environment, nearby communities, consumer health, and animal welfare.

It shouldn’t have to be this way. It's time to fix our broken food system. It's time to look for alternatives. Lab-grown meat could hold the key.

bs are only involved now, in order to support ongoing research and development. Once they begin to produce at scale, lab-grown meat companies will swap out laboratories for facilities that resemble microbreweries—a far cry from the industrial farms that profit off of the horrific exploitation, abuse, and slaughter of sentient .


Environmental effects 

The scientific research is clear: factory farming is an environmental disaster. The industrial farming of animals is a major driver of climate change, deforestation, air and water pollution, and other planetary hazards.

Industrial livestock systems – particularly cattle farms – are responsible for the emission of huge quantities of greenhouse gases like CO₂ and methane. But growing meat from cells can have a similar – and sometimes even worse – environmental footprint.


How is lab grown meat made

Instead of killing animals for their meat, the process of making lab-grown meat starts with the careful removal of a small number of muscle cells from a living animal, typically using local anesthesia to provide relief from pain. The animal will experience a momentary twinge of discomfort, not unlike the feeling of getting a routine blood test at the doctor’s office. This process is much less harmful than the lifetime of pain and terror animals experience leading up to their horrific final moments at the slaughter house.

Lab grown meat has the exact same animal cells as what we traditionally consider “meat”—the flesh of an animal. The difference has to do with how it gets to your plate: lab-grown meat comes from cells harvested from a living animal, while conventional meat comes from an animal that’s raised and killed for human consumption.

Then, a lab technician places the harvested cells in bioreactors before adding them to a bath of nutrients. The cells grow and multiply, producing real muscle tissue, which scientists then shape into edible “scaffoldings.” Using these scaffoldings, they can transform lab-grown cells into steak, chicken nuggets, hamburger patties, or salmon sashimi. The final product is a real cut of meat, ready to be marinated, breaded, grilled, baked, or fried—no animal slaughter required.


First public trial 

The first cultured beef burger patty was created by Mark Post at Maastricht University in 2013.[54] It was made from over 20,000 thin strands of muscle tissue, cost over $300,000 and needed 2 years to produce.

The burger was tested on live television in London on 5 August 2013. It was cooked by chef Richard McGeown of Couch's Great House Restaurant, Polperro, Cornwall, and tasted by critics Hanni Rützler, a food researcher from the Future Food Studio, and Josh Schonwald. Rützler stated, "There is really a bite to it, there is quite some flavour with the browning. I know there is no fat in it so I didn't really know how juicy it would be, but there is quite some intense taste; it's close to meat, it's not that juicy, but the consistency is perfect. This is meat to me... It's really something to bite on and I think the look is quite similar." Rützler added that even in a blind trial she would have taken the product for meat rather than a soya copy.


Lab grown meat effects

Some scientists and their research shows some concerns about Meat produced from cultured cells could be 25 times worse for the climate than regular beef unless scientists find ways to overhaul energy-intensive steps in its production.

Some researchers speculate that depending on the efficiency of the production process, the rise of the cultured meat industry could actually make climate change worse than traditional beef production. One issue is the longer lasting impact of carbon pollution versus methane gas pollution.

"Lab meat doesn't solve anything from an environmental perspective, since the energy emissions are so high," said Marco Springmann, a senior environmental researcher at the University of Oxford.

Some lab-grown meat contains an animal by-product known as fetal bovine serum (FBS). Slaughterhouses obtain fetal bovine serum by collecting blood from the unborn calves of pregnant cows after they’re killed. San Francisco-based lab-grown meat producer Eat Just uses a “very low level” of the serum in its chicken, which is the first lab-grown meat product to hit the market.

However, companies are quickly pivoting to find alternatives to FBS. In response to ethical concerns about using a slaughter house by product in the otherwise lab-grown meat, Dutch startup Mosa Meat revealed this year that it had successfully eliminated FBS from its process. Eat Just is also developing an animal-free alternative to fetal bovine serum.

Scientists are working for try to make lab grown meat more healthy which full fill nutritions requirements with in  low cast.


History

The theoretical possibility of growing meat in an industrial setting has long been of interest. In a 1931 essay published by various periodicals and later included in his work Thoughts and Adventures, British statesman Winston Churchill wrote: "We shall escape the absurdity of growing a whole chicken to eat the breast or wing, by growing these parts separately under a suitable medium."


Initial research 

In the 1950s, Dutch researcher Willem van Eelen independently came up with the idea for cultured meat. As a prisoner of war during the Second World War, Van Eelen suffered from starvation, leaving him passionate about food production and food security. He attended a university lecture discussing the prospects of preserved meat. The earlier discovery of cell lines provided the basis for the idea.


Vitro cultivation of first muscle fibers 

In vitro cultivation of muscle fibers was first performed successfully in 1971 when pathologist Russel Ross cultured guinea-pig aorta.


Tissue engineering 

In 1991, Jon F. Vein secured patent US 6835390 for the production of tissue-engineered meat for human consumption, wherein muscle and fat would be grown in an integrated fashion to create food products.


Cultured meat production 

In 2001, dermatologist Wiete Westerhof along with van Eelen and businessperson Willem van Kooten announced that they had filed for a worldwide patent on a process to produce cultured meat.[43] The process employed a matrix of collagen seeded with muscle cells bathed in a nutritious solution and induced to divide.

That same year, NASA began conducting cultured meat experiments, with the intent of allowing astronauts to grow meat instead of transporting it. In partnership with Morris Benjaminson, they cultivated goldfish and turkey.

In 2003, Oron Catts and Ionat Zurr exhibited a few centimeters of "steak", grown from frog stem cells, which they cooked and ate. The goal was to start a conversation surrounding the ethics of cultured meat—"was it ever alive?", "was it ever killed?", "is it in any way disrespectful to an animal to throw it away?"

In the early 2000s, American public health student Jason Matheny traveled to India and visited a factory chicken farm. He was appalled by the implications of this system. Matheny later teamed up with three scientists involved in NASA's efforts. In 2004, Matheny founded New Harvest to encourage development by funding research. In 2005 the four published the first peer-reviewed literature on the subject.

In 2008, PETA offered a $1 million prize to the first company to bring cultured chicken meat to consumers by 2012. The contestant was required to complete two tasks to earn the prize:

- produce a cultured chicken meat product that was indistinguishable from real chicken and

- produce the product in large enough quantities to be competitively sold in at least 10 states.

The contest was later extended until 4 March 2014. The deadline eventually expired without a winner.

In 2008, the Dutch government invested $4 million into experiments regarding cultured meat. The In Vitro Meat Consortium, a group formed by international researchers, held the first international conference hosted by the Food Research Institute of Norway in April. Time magazine declared cultured meat production to be one of the 50 break through ideas of 2009. In November 2009, scientists from the Netherlands announced they had managed to grow meat using cells from a live pig.


First public trial

The first cultured beef burger patty was created by Mark Post at Maastricht University in 2013. It was made from over 20,000 thin strands of muscle tissue, cost over $300,000 and needed 2 years to produce.


Industrial development

Between 2011 and 2017, many cultured meat startups were launched. Memphis Meats (now Upside Foods[58]) launched a video in February 2016, showcasing its cultured beef meatball. In March 2017, it showcased chicken tenders and duck a l'orange, the first cultured poultry shown to the public.

An Israeli company, SuperMeat, ran a crowdfunding campaign in 2016, for its work on cultured chicken.

Finless Foods, a San Francisco-based company working on cultured fish, was founded in June 2016. In March 2017 it commenced laboratory operations.

In March 2018, Eat Just (in 2011 founded as Hampton Creek in San Francisco, later known as Just, Inc.) claimed to be able to offer a consumer product from cultured meat by the end of 2018. According to CEO Josh Tetrick the technology was already there. JUST had about 130 employees and a research department of 55 scientists, where cultured meat from poultry, pork and beef was researched. JUST has received investments from Chinese billionaire Li Ka-shing, Yahoo! co-founder Jerry Yang and according to Tetrick also by Heineken International and others.

On 27 April 2022, the European Commission approved the request for the collection of signatures for the European Citizens' Initiative End The Slaughter Age to shift subsidies from animal husbandry to cellular agriculture.


Market entry

European Union 

In the European Union, novel foods such as cultured meat products have to go through a testing period of about 18 months during which a company must prove to the European Food Safety Authority (EFSA) that their product is safe. In March 2022, cultured meat producers had reached the level of attempting to gain regulatory approval from European Union supranational institutions coming just before mass goods could be sold to consumers. By February 2023, none had yet submitted a novel food dossier for approval by the EFSA. Legal experts explained this as having to do with the fact that, although the EFSA's novel food procedure has been well-established since 1997 (unlike in other jurisdictions, that still have or had to develop certain regulatory standards), it is a long and complicated process in which companies can have little imput once they have submitted their request, unlike cultured meat startups in the United States (who could easily communicate back and forth with the FDA to clarify any issues), and in the UK, Singapore and Israel (where governments have implemented a 'single point of contact' responsible for the overall process).


Israel

In November 2020, SuperMeat opened a 'test restaurant' in Ness Ziona, Israel, right next to its pilot plant; journalists, experts and a small number of consumers could book an appointment to taste the novel food there, while looking through a glass window into the production facility on the other side. The restaurant was not yet fully open to the public, because as of June 2021 SuperMeat still needed to wait for regulatory approval to start mass production for public consumption, and because the COVID-19 pandemic restricted restaurant operations. By February 2023, Israeli authorities had established a regulatory structure similar to that of Singapore, and shown a general willingness to work towards approval (as well as financing research for cultivated food innovation), but were still in the process of developing safety regulations in consultations with researchers and other experts. For example, the Israeli Health Ministry and UN Food and Agriculture Organization (FAO) co-organised a convention of cultivated food safety regulation experts in September 2022.


Singapore

On 2 December 2020, the Singapore Food Agency approved the "chicken bites" produced by Eat Just for commercial sale. It marked the first time that a cultured meat product passed the safety review (which took 2 years) of a food regulator, and was widely regarded as a milestone for the industry. The chicken bits were scheduled for introduction in Singaporean restaurants. Restaurant "1880" became the first to serve cultured meat to customers on Saturday 19 December 2020. In January 2023, the SFA also granted regulatory approval for the production of cultured meat with serum-free media to Eat Just' subsidiary GOOD Meat, which had introduced its clean chicken product in several more Singaporese restaurants as well as hawker centres and food delivery services since 2020, and was constructing the bioreactors for its new facility in Singapore. This world-first approval was said to be a milestone in making cultivated meat production more scalable and efficient.


United States

In May 2022, Finless Foods launched pokè-style plant-based tuna product at National Restaurant Association's Show, with availability at restaurants and foodservice operators across the United States. In November 2022, the Food and Drug Administration (FDA) completed the pre-market consultation of Upside Foods (formerly Memphis Meats), concluding that its products were safe to eat, a first for cultivated meat companies in the United States.[99] Only the United States Department of Agriculture (USDA) still had to finalise the labelling and inspection process; as of April 2023, this last hurdle to U.S. market entry was expected to be overcome somewhere in 2023.





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