Butylparaben use

Catalytic Synthesis of a sulfuric acid, butyl paraben

Sulfuric acid catalyzed esterification method is the classic method of synthetic esters, synthetic parabens, the hero Hasegawa, Atsushi Maekawa governance and Xie Wei Yang and has long been reported. Such a catalytic reaction for a long time, low yield, alcohol consumption, and improve the use of p-hydroxybenzoic acid, n-butanol, benzene and sulfuric acid molar ratio of 1: 3.5: 1: 0.015, refluxing 1 h , n-butyl paraben yield up to 99.12%, with an average yield of 97.58%.
Ming et al pipe coil in toluene as the solvent, when p-hydroxybenzoic acid, n-butanol and toluene molar ratio of 1: 4: 2, with sulfuric acid as a catalyst, refluxing 4 h, then the solvent was distilled off and 50% alcohol, cooling precipitation precipitation, filtration, n-butyl paraben was 89.3% yield. Zhengxue Zhong et without organic solvent with n-butanol as a dehydrating agent, p-hydroxybenzoic acid, n-butanol and sulfuric acid molar ratio of 1: 3.5: 0.15, refluxing 0.75 h, p-hydroxybenzoate n-butyl formate yield of 98.4%.
To improve the storage and ease of use, tubes and the like to the disc-ming sulfate SO4 2- / bentonite catalyst (mass fraction of about 5%), with toluene as the solvent, when p-hydroxybenzoic acid, n-butanol and toluene molar ratio of 1: 4 : 2, in the <110 ℃ stirred refluxing 5h, then steamed out 50 percent of solvents and alcohol, cooled to precipitate precipitation, filtration to obtain the product of n-butyl paraben, yield 88.6%.
To accelerate the reaction process under microwave irradiation synthesis of n-butyl paraben, when p-hydroxy benzoic acid, n-butanol molar ratio of 1: 4, the use of sulfuric acid as a catalyst in the working frequency of the microwave radiation source 2450MHz 30min, n-butyl paraben yield of 85.1%, rather than use the microwave, you need to refluxing 300min, product yield was 83.8%, so the reaction rate increased by 10-fold.
2 sulfonic acid catalytic synthesis of butyl paraben

2.1 p-toluenesulfonic acid
Since the sulfuric acid cause side reactions when heated organic etherification, oxidation, carbonization, sulfonation, while its corrosion resistance, operation, use and storage is not convenient and safe. Toluenesulfonic acid (p-CH3C6H4SO3H.H2O) is an organic acid, sulfuric acid can overcome many shortcomings, easy to use, is a good catalyst for esterification, can be synthesized in high yields of hydroxy esters. The author has used 0.05mol paraben, 0.30mol alcohol in 0.0052mol (1.0g) under refluxing toluene sulfonic acid catalysis 3h, n-butyl paraben yield of 95.9% . Since the p-toluenesulfonic acid dissolved in an organic reaction system, the reaction liquid after the reaction the acid is still strong, the need for treatment, there is a certain waste liquid, the catalyst can not be reused. Shi Lei, such as 10g of granular activated carbon immersed in 60mL mass fraction of 25% aqueous solution of toluene sulfonic acid 30h, drained after too 15.31g, immobilization rate of 53.10%, select this catalyst 0.6g, 0.1mol hydroxybenzoic acid, 0.3mol butanol refluxing 3h, n-butyl paraben yield of 98.02%, the catalyst can be reused five times, the yield was still up 97.65% [9 ]. This method is easy to operate, reducing environmental pollution, high ester yield, catalyst reuse performance, is a good catalyst.

2.2 amino acid
Sulfamic acid (H2N-SO2OH) with p-toluenesulfonic acid, as is also an inexpensive, readily available, stable solid. Transport, storage, easy to use, except that it is insoluble in organic reaction system, easy separation, can be reused, for small equipment corrosion, high yield synthesis products is a good catalyst for the synthesis of butyl paraben. When the right-hydroxy acid, n-butanol and the amino acid molar ratio of 1: 4: 0.41 refluxing 3h, n-butyl paraben yield of 97.9%. When converted to butanol isobutanol, p-hydroxybenzoic acid, isobutyl alcohol, an amino acid molar ratio of 1: 6: 0.52 refluxing 3h, p-hydroxybenzoic acid yield of 90.7 Isobutyl %.
2.3 strong acid cation exchange resin
Strong acid cation exchange resin is a polymer acid, cheap, no corrosion of equipment, do not pollute the environment, does not cause side effects, and the resin is insoluble in the reaction system, recyclable, recycled and reused, easy to operate , product yield, is an effective catalyst for industrial production. Using five kinds of models of the resin (D72, D61, dry hydrogen resin, HD-8 and JK008) catalytic synthesis of ethyl paraben, Discovery JK008 resin highest activity. When the p-hydroxybenzoic acid to the resin mass ratio of 1: 0.08, p-hydroxybenzoic acid with n-butanol molar ratio of 1: 5.5, refluxing 4.5h, obtained by gas chromatographic analysis of n-butyl p-hydroxybenzoate ester yield of 98.0%, JK008 resin has good reuse catalytic performance.
Introducing benzene sulfonic acid groups on the benzene ring zirconium, made a similar strong acid cation exchange resin solid acid – acid sulfonated benzene zirconium (ZSPP), catalytic synthesis of n-butyl paraben. Specific conditions: 0.05mol paraben, 0.20mol n-butanol, 1g ZSPP catalyst at 117¯120 ℃ refluxing 8 h, n-butyl paraben yield of 92%, this catalyst can reuse reused 10 times, the yield is still about 90%, the catalyst has a high thermal stability (over 250 ℃ was released SO2) than the sulfonic acid resin, an organic substance at high temperature coking, no corrosion of equipment application prospect is a solid acid catalyst promising.

3 Catalytic Synthesis of inorganic salts and oxides of butyl paraben
Catalytic and catalytic sulfuric acid were discussed earlier proton acid catalysis, catalytic inorganic salts and oxides vary due to different compounds. There are a large class of inorganic materials is cheap and easy to get the Lewis acid, the metal atom has with the carboxylic acid carbonyl oxygen ligands empty track, which has catalyzed esterification, while their small equipment corrosion, pollution reduction, catalyst with less, is a good catalyst for the synthesis of certain esters. Iron (Ⅲ) electronegativity strong, Fe3 + in outer space orbit with the carboxylic acid carbonyl oxygen ligands. Liu Yong, etc. using Fe2 (SO4) 3 · xH2O catalytic synthesis of n-butyl paraben: 0.1mol paraben, 0.4mol n-butanol, 0.5g of the catalyst under refluxing 4h, acid conversion rate of 91.6%, after going alcohol, after recrystallization paraben, n-butyl ester yield of 85% fine. Acetate Catalyzed, who used hydroxybenzoic acid and n-butanol molar ratio of 1: 4 to 4% of the mass fraction (based on the total reactant meter) chloride as catalyst different refluxing 5 h, then the catalyst was filtered off, the alcohol is recovered by distillation, the crude ester are precipitated by the water, an alkali, washed with water, then ethanol – n-butyl p-hydroxybenzoate may, after finishing the water of crystallization yield of an ester, respectively:
Catalyst CaCL2 ZnCL2 FeCL3 · 6H2O ALCL3 · 6H2O
Ester yield /% 30307883
Thus, chloride has a catalytic role, especially FeCl3 · 6H2O and AlCl3 · 6H2O is a good catalyst for the synthesis of the esters. Previously, Zhang Jing Qing, who have also been reported: When right-hydroxy acid with n-butanol molar ratio of 1: 3.5, FeCl3 · 6H2O mass fraction (the total mass of reactants) of 5%, in 139¯ under 140 ℃ reaction 1.5h, 84.6% of the available yield of n-butyl paraben [17]. Wang Mingxing, etc. have also been studied: when hydroxybenzoic acid, n-butanol and FeCl3 · 6H2O molar ratio of 1: 2: 0.12 refluxing 3h, the yield of n-butyl paraben 95 .1% ¯96.3% [18]. Yao spring, also reported the catalytic effect of FeCl3 · 6H2O, in its optimum conditions, product yield was 98.9%.
Tin (II) is also high negative elements, such as the use of cost Prudential stannous oxide (SnO) as catalyst was successfully synthesized n-butyl paraben: 0.1mol paraben, 0.3mol n-butanol . 5gSnO, 140 ℃ refluxing 4h, acid conversion rate of 96%.
Since most of the inorganic chlorides hygroscopic and difficult to use and accurate storage, and they were dissolved in the reaction system, to the product separation and purification inconvenience. Ammonium ferric sulfate is a stable crystal, in addition to having the chloride advantages, it is not easy to absorb moisture, insoluble in the reaction system, the reaction to form a loose spherical solid, non-corrosive reaction equipment, is a good ester catalyst. Deng Xuzhong such as the use of its catalytic synthesis of n-butyl paraben: 0.1mol paraben, 0.35mol n-butanol, 1.0g catalyst refluxing 4 h, the crude ester yield of 93.7% , after recrystallization from ethanol the yield was 90.1% fine ester.
Li Xiaoli, such as the use of rare earth oxide, neodymium oxide (Nd2O3) catalytic synthesis of n-butyl paraben, its optimal reaction conditions: When right-hydroxy acid, n-butanol molar ratio of 1: 4, the amount of catalyst of 5% by mass of p-hydroxybenzoic acid, refluxing 4h, yield of the ester was 81.2% and the good catalytic effect is repeated, the method to reduce the corrosion of equipment and environmental pollution, has certain industrial value.
Catalytic inorganic discussed above is part of Lewis acid catalysis. The authors note monohydrate sodium bisulfate (NaHSO4 · H2O) is also a good esterification catalyst, inexpensive, readily available, and stable crystal properties, and its solution is strongly acidic, due to ionizing HSO4- have H + exists, belongs to the proton acid catalysis, capable of catalyzing the synthesis of butyl paraben: When hydroxybenzoic acid, n-butanol and sodium hydrogen sulfate monohydrate molar ratio of 1: 2: 0.072 when refluxing 5h, n-butyl paraben ester yield of 92.8%; when paraben, isobutyl alcohol and sodium hydrogen sulfate monohydrate molar ratio of 1: 3: 0.036 refluxing 7h, isobutyl paraben yield can also be 99%. Of microwave radiation sodium bisulfate next catalytic synthesis of butyl paraben work, the optimization of reaction conditions: when n (alcohol): n (acid): n (NaHSO4 · H2O) = 0.15: 0 .05: 0.058, using the power of 210W microwave radiation 28min, product yield was 93.6%. The catalyst and the reaction time is shortened, the remaining sodium bisulfite and has a repetitive catalytic performance due to their insoluble in the reaction system, the corrosion of the equipment is greatly reduced, there is a catalyst for industrial application.

N-acetyl-L-tyrosine (ACETYLTYROSINE) Information

Basic Information
Chinese name: N- Acetyl Tyrosine -L-
Chinese alias: Acetyl Tyrosine
English name: N-acetyl-L-tyrosine
English Synonyms: L-TYROSINE, N-ACETYL -; [1] ACETYLTYROSINE; ACETYL-L-TYROSINE; AC-TYR-OH; AC-TYROSINE; N-AC-L-TYR; N-ACEYL-L-TYROSINE; (2S) -2- (acetylamino) -3- (4-hydroxyphenyl) propanoate
CAS: 537-55-3
EINECS: 208-671-3
Formula: C11H12NO4
Molecular Weight: 222.2178
2 Physical Properties
Melting point: 149-152 ℃
Boiling point: 531.3 ° C at 760 mmHg
Flash Point: 275.1 ° C
Vapor Pressure: 4.07E-12mmHg at 25 ° C
Specific rotation of 47.5 ° (c = 2, water)
3 Use
N- acetyl tyrosine -L- important for fine organic chemical intermediates, widely used in medicine, pesticides, chemical industry and other fields.

L-threonine Use

1 is mainly used as nutritional supplements. Easy to generate heat with glucose Jiao Xiang and chocolate flavor, aroma role there. Can also be used for biochemical studies.
2 for nutritional supplements, threonine is an essential amino acid. Threonine often added to minors piglets and poultry feed, is the second limiting amino acid and poultry feed, pig feed third limiting amino acid. Added to wheat, barley and other grain-based feed.
3 nutritional supplements, also used in the preparation of amino acid infusion and a comprehensive amino acid preparations.
4 for the adjuvant treatment of digestive ulcers. Also can cure anemia and angina, aortic inflammation, heart failure and other cardiovascular disorders.
5 threonine (L- threonine) by W. C. Rose 1935 Isolation and identification from the fibrous protein hydrolyzate, has been shown to be essential amino acids was finally discovered, it is the second or third limiting amino acid in poultry, it has an extremely important role in animal physiology . Such as promoting growth, improve immune function, etc.; balanced dietary amino acids, amino acids closer to the ideal ratio of protein, thereby reducing animal protein in feed requirements. Lack threonine, can lead to reduced feed intake of animals, stunted, feed utilization decreased immune function suppression and other symptoms. In recent years, lysine, methionine synthetics been widely used in animal feed, threonine becoming affect animal performance limiting factor, further study of threonine help effectively guide the livestock and poultry production .
Threonine (L- threonine) is the animal itself can not be synthesized amino acids but much needed, can be used to precisely balance the amino acid composition of feed, animal growth to meet the need to maintain and improve weight gain and lean meat, lower feed meat ratio; feed ingredients to improve the nutritional value of low amino acid digestion, improve the performance of low-energy feed production; may reduce feed crude protein level, improve feed nitrogen utilization, reduce feed costs; can be used for pigs, chickens, ducks and senior aquatic feeding and breeding. L- threonine is the use of bio-engineering principles, corn starch and other raw materials through submerged fermentation, refining and production out of the feed additive. Adjustable feed amino acid balance, promote growth and improve meat quality, improve the nutritional value of feed ingredients with low amino acid digestion, producing low-protein diet, protein helps save resources, reduce the cost of feed ingredients, reduce animal manure and urine the nitrogen content, Chuqin ammonia concentration and release rate. Widely used to add piglet feed, pig feed, chicken feed, shrimp feed and eel feed.
6 threonine (L- threonine) in the decomposition of the body’s metabolism, not only through deamination and transamination role, but directly by threonine dehydratase, threonine dehydrogenase and threonine aldolase catalytic conversion of acid is an amino acid other substances, for example, threonine can be converted to butyryl coenzyme A, succinyl coenzyme a, serine, glycine and the like. Also threonine excess glucose can increase lysine -α- keto acid reductase activity, add the appropriate amount of threonine can eliminate excess lysine in the diet caused due to body weight gain decreased, liver, muscle tissue protein / deoxyribonucleic acid (DNA), ribonucleic acid (RNA) / DNA ratio decreased. Add threonine tryptophan or methionine also reduce the growth inhibition caused by excessive. According to reports, the chicken to absorb most of threonine in the duodenum, crop Mang and Proventriculus rapidly absorbed into the liver threonine protein deposition in the body.

Isothiazolinone Properties and Uses

Isothiazolin-one composed of 5 – chloro-2 – methyl – 4 – isothiazolin-3 – one (CMI) and 2 – methyl – 4 – isothiazolin-3 – one (MI) components. Isothiazolin-off one by bacteria and algae protein sky biocidal action key. Isothiazolin-one contact with the microorganisms that can rapidly and irreversibly inhibit their growth, leading to the death of microbial cells, so the common bacteria, fungi, algae has a strong inhibitory and killing effect. High killing efficiency, good degradation, with no residual, safe operation, good compatibility, stability, and low cost. With chlorine and most cation, anion and non-ionic surfactant miscible. When high doses isothiazolin-ketone biological slime stripping a significant effect.

Isothiazolin-ketone is a broad spectrum, high efficiency, low toxicity and non-oxidizing biocide. Widely used in oil, paper, pesticide, cutting oil, leather, ink, dye, leather and other industries.

Technical indicators:

Industry standard HG / T 3657-2008 Water treatment chemicals isothiazolin derivatives

Project	Index
Class 1	Class 2
Exterior	Brown transparent liquid	Yellow or light green transparent liquid
Active content /%	14.0 to 15.0	1.50 ~ 1.80
pH value	2.0-4.0	2.0-5.0
Density (20 ℃) g / cm	1.26 ~ 1.32	1.02 ~ 1.05
CMI / MI (mass percentage) /%	2.5-3.4	2.5-3.4

Use

When isothiazolin ketones 2 products as sludge remover, dosing concentration of 150-300mg / L; when making fungicide, dosing once every 3-7 days, the dosage 80 ~ 100mg / L. With chlorine and other oxidizing biocides used simultaneously, can not be used in cooling water system containing sulfur. Isothiazolin-one quaternary ammonium salt, the effect will be better.

Isothiazolin-ketone used as industrial mildew, general concentration of 0.05-0.4%

Packaging and Storage

Isothiazolin-one plastic drum, 25Kg per barrel or according to user requirements; stored in a cool room, storage for ten months.

Security

Isothiazolin-ketone is corrosive to skin and eye irritation, the operation should be equipped with protective goggles and rubber gloves, once contact with skin, eyes, rinse immediately with plenty of water. If contact with skin, immediately remove contaminated clothing and shoes, rinse with plenty of water for at least 15 minutes, acetic acid urea ointment applied to the affected area or burn ointment, and seek immediate medical attention

Hyaluronic acid Details

Glycosaminoglycans (formerly called mucopolysaccharides, amino polysaccharides and acidic polysaccharides) in the structure of the simplest kind, it is by repeating disaccharide units
GlcUA-β (1 → 3) -GlcNAc, with β-1,4 glycosidic linkage formed. In the body, often in free form or covalently (proteoglycan complexes) in the form of complexes present.
The surface of the molecule contains many hydrophilic groups, can draw their physical 1,000 to 10,000 times the volume of water, keeping the moisture of loose connective tissue is important; while the viscosity of the HA has a strong, and the joints with a vitreous Run wet and protection; well promote wound healing.
HA is present in the extracellular matrix of connective tissue of animals. Among them, the bovine vitreous, human umbilical cord and rooster combs are commonly used material extracted HA. HA is widely used in cosmetics, artificial joints, surgical lubricants and other products. United States Food and Drug Administration (FDA) approval in 2003 through the use of injection patches of skin wrinkles.

Glycine Use

Food
[Use a]
For biochemical reagents, used in medicine, feed and food additives, fertilizer industry as a non-toxic agent decarbonization
[Use two]
For the pharmaceutical industry, biochemical tests and organic synthesis
[Uses three]
Glycine is mainly used as chicken feed nutritional additives.
[Uses four]
Also known as the amino acid glycine (aminoacetic acid), glycine ethyl ester hydrochloride intermediates in the synthesis of pyrethroid insecticides used in pesticide production, but also synthetic fungicide iprodione and solid glyphosate herbicide, another it is also used in fertilizers, pharmaceuticals, food additives, spices and other industries.
[Use five]
Nutritional supplements. Mainly used for flavoring and so on.
Flavored with alanine together for alcoholic beverages, the addition of: Wine 0.4%, 0.2% whiskey, champagne 1.0%. Others such as powdered soup about 2%; lees pickled foods 1%. Because it can to a certain extent was shrimp, cuttlefish flavor, can be used for sauces.
B. subtilis and E. coli have certain reproductive inhibition. It can be used as surimi products, preservatives such as peanut butter, add the amount of 1% to 2%.
Because glycine buffer having zwitterionic amino and carboxyl, so there is a strong cushioning. Taste for salt and vinegar can sense a dampening effect. Dosage salted products 0.3% ~ 0.7%, pickled goods 0.05% to 0.5%.
Antioxidant effect (using its metal chelation) added to butter, cheese, margarine extend the shelf life of 3 to 4 times. To make baked goods in lard stable, glucose 2.5% and 0.5% glycine. Adding 0.1% to 0.5% of wheat flour with the speed of cooking, and can play the role of flavoring. Medicine for antacids (hyperacidity), Muscular Dystrophy therapeutic agent antidotes. Synthetic materials also threonine amino acids.
According to the provisions of GB 2760-96 used as a spice.
[Uses six]
Used as a buffer for the preparation of tissue culture media, copper, gold and silver test, medicine for the treatment of myasthenia gravis and progressive muscular atrophy, hyperacidity, chronic enteritis, children and other high-proline hyperlipidemia disease.
[Purpose seven]
Treatment of myasthenia gravis and progressive muscular atrophy; treat excessive stomach acid ester disease, chronic enteritis (often in combination antacid); combination with aspirin, can reduce its stimulation of the stomach; treatment of children with high proline hyperlipidemia; as generate non-essential amino acid nitrogen source, adding a mixed amino acid injection.
[Uses eight]
The product is used as a solvent to remove carbon dioxide in the fertilizer industry. In the pharmaceutical industry, can be used as amino acid preparations, chlortetracycline buffer and as an anti-Parkinson’s disease drugs L- synthetic materials dopa, is ethyl imidazole intermediates, which itself is an adjunct therapy medicine, to treat neurological hyperacidity, gastric ulcer inhibiting excessive acid is also effective. Workers in the food industry for the synthesis of the wine, brewing products, meat processing and refreshing drink recipes and saccharin to-agent, as a food additive, glycine can be used alone as a condiment, but also with sodium glutamate, DL- alanyl acid, citric acid, etc. used in conjunction. In other industries, as a pH adjusting agent, added to the plating solution, or other amino acids used as starting materials. For biochemical reagents and solvents in organic synthesis and biochemistry.
[Purpose nine]
Metallochromic indicator, solvents.

Butyl Paraben Inspection

Clarity and color of solution to take this product 1.0g, 10ml ethanol dissolved, the solution should be clear and colorless; such as color, with a yellow or yellow-green on the 1st standard colorimetric solution (Appendix Ⅰ Ⅹ A first law), shall not be deeper.
Acidity solution 2ml under “Clarity and color of solution” item, namely ethanol 2ml, water, 5ml, shake, bromocresol green indicator solution add 2 drops of sodium hydroxide (0.1mol / L) titrated to was blue, consume titrant (0.1mol / L) should be not more than 0.1ml.
Chloride take this product 2.0g, add water 50ml, heated to 80 ℃, let cool, filtered; the filtrate 5.0ml, check (Appendix Ⅷ A) according to the law, with a standard solution of sodium chloride solution 7.0ml compare and contrast made, shall not be thicker (0.035%).
Sulfate take the above filtrate 25ml, according to inspection (Appendix Ⅷ B), potassium sulfate solution 2.4ml comparison with the standard control solution made no thicker (0.024%).
Take some relevant material, plus the mobile phase and dilute containing 1mg per 1ml solution as the test solution; take Butylparaben reference amount, plus the mobile phase and dilute made per 1ml 0.01mg solution as the reference solution; another methylparaben and Ethylparaben amount, plus mobile phase and diluted into a mixed solution containing 0.01mg per 1ml of. High performance liquid chromatography (Appendix Ⅴ D) was measured. Octadecylsilane bonded phase silica as a filler; in 1% acetic acid – methanol (40:60) as the mobile phase; detection wavelength of 254nm. Take a mixed solution 20μl into the liquid chromatograph, record the chromatogram separation, Methylparaben Ethylparaben peak and peak should meet the requirements. Reference solution 20μl, into the liquid chromatograph, adjust the sensitivity, the principal component peak height of about 20% to 25% of full scale; then the precise amount of the test solution and reference solution 20μl, injection liquid chromatograph, record the chromatograms to 2 times the peak retention time. Test solution chromatogram as significant impurity peaks, a single impurity peak area no larger than the reference solution 0.4 times the area of the main peak (0.4%), the impurity peak area no larger than the reference solution and the main peak area of 0.8 times (0.8%).
Drying of this product with silica gel desiccant, vacuum drying to constant weight, weight loss shall not exceed 0.5% (Appendix Ⅷ L).
Residue on ignition to take this product 1.0g, according to the determination (Appendix Ⅷ N), no residue left over 0.1%.
Heavy metals residue left over residue on ignition under, according to the determination (Appendix Ⅷ H Second Law), containing heavy metals must not exceed twenty millionths.
Arsenic take this product 1.0g, calcium hydroxide 1.0g, mix, add water, stir, after drying, the first small fire burning so carbonized, and then at 500 ~ 600 ℃ ignition completely gray, immediately put in an ice bath in let cool, add 5ml of hydrochloric acid and water, 23ml, according to inspection (Appendix Ⅷ J first law), shall meet the requirements (not more than 0.0002%

Allantoin main purpose

1, in medicine: allantoin promote cell growth, accelerate wound healing, the physiological function of keratin, such as softening, anti-ulcer agents, and good healing agents of skin wounds. Can be used to alleviate symptoms and treatment of dry skin, scaly skin disease, skin ulcers, peptic ulcers and inflammation, osteomyelitis, diabetes, cirrhosis of the liver, acne have a better effect.
2, in cosmetics: Because allantoin is an amphoteric compound that binds to a variety of substances to form double salts, with dark, antiseptic, analgesic, anti-oxidation, to keep the skin moisture, moist and soft, is Beauty salons and other cosmetic effects of additives, widely used freckle cream, acne solution, shampoo, soap, toothpaste, shaving lotion, conditioner, astringent, anti-sweat deodorant lotion and other additives. Add allantoin cosmetics with conservation organizations, hydrophilic, water and prevent water distribution and so on; adding allantoin hair cream, hair cream, shampoo, hair has a protective effect, can not forked hair constantly hair; adding allantoin lipstick, creams make the skin, lips soft and flexible, and has a beautiful sheen. Allantoin to promote tissue growth, cell metabolism, soften the cuticle proteins. For example magic care magic lip care moisturizing gentle exfoliating scrub to soften the film, moisturizing and shiny main function is to increase the role of allantoin.
3, in agriculture: allantoin is an excellent plant growth regulator, can stimulate plant growth, wheat, citrus, rice, vegetables, soybeans significantly increase yield, and solid fruit, premature action.

Barium hydroxide Applications

Synthetic phenolic resin as a catalyst, the polycondensation reaction is easy to control, a resin obtained low viscosity, fast curing, easy to remove the catalyst. Reference to the amount of 1% to 1.5% phenol. The catalyst may also be used as a water-soluble urea-modified phenol-formaldehyde adhesive, the cured product was a pale yellow, resin remaining in the barium salt of divalent and does not affect the chemical stability of the dielectric.
Reagents for the analysis, but also for the separation and manufacture of precipitated barium sulfate salts, measuring carbon dioxide in air. Quantitative chlorophyll. Refined sugar and animal and vegetable oils. Boiler water cleaner. Pesticides. Rubber industry.

PRAZIQUANTEL laboratory determination

Method name: praziquantel tablets – praziquantel – High Performance Liquid Chromatography
Applications: The method for determining the content of praziquantel praziquantel tablets using high performance liquid chromatography.
This method is applicable to praziquantel tablets.
Method: the small study sample, internal standard solution dissolved in methanol and then diluted into the HPLC chromatography with UV absorbance detector at a wavelength of 263nm peak area detected praziquantel, calculated its content.
Reagents: 1 methanol
2. Α-asarone
Equipment: 1 Instrument
1.1 HPLC
1.2 column
Octadecylsilane bonded silica as a filler
1.3 UV absorption detector
2 chromatographic conditions
2.1 mobile phase: methanol-water = 10040
2.2 detection wavelength: 263nm
2.3 column temperature: room temperature
Preparation of internal standard solution 1: Sample Preparation.
Precision Weigh α-asarone amount, dissolved in methanol and diluted into each 1mL solution containing 0.4mg, namely the internal standard solution.
Preparation of 2 reference solution
Precision Weigh praziquantel reference about 100mg, set 10mL volumetric flask, precision internal standard solution 5mL, and shake to dissolve, diluted with methanol to the mark, shake, is the reference solution.
Preparation of the test solution 3.
20 to take the test, accurately weighed, small study, accurately weighed amount (approximately equivalent to praziquantel 100mg), set 10mL volumetric flask, precision internal standard solution 5mL, and shake to dissolve, dilute with methanol to scale, shake, that is, the test solution.
Note: “Precision Weigh” means to check the weight should be accurately referred to take the weight of one-thousandth. ‘Precise amount “means the amount of the volume should meet the accuracy requirements of national standards for the volume pipettes.
Steps: precision drawing reference solution and the test solution 10mL, high performance liquid chromatography with UV absorbance detector praziquantel (C19H24N2O2) at a wavelength of 263nm peak area, calculates its content.