The Content Determination Of Several Disabled Ingredients And Heavy Metal In Cosmetic

According to?Hygienic Standard for Cosmetics?of China,hydroquinone,phenol,metronidazole,chloramphenicol is forbidden to cosmetics.Heavy metals are restricted ingredient to cosmetics?If the cosmetics with above ingredient are used by people,it is likely to cause the damage to skin or even body of consumer.In order to guarantee the safety of cosmetics,the following research works are conducted:The method of use chromatography-diode array detector with high performance is established to determine the content of hydroquinone and phenol in the freckle whitening cosmetic.The condition for the chromatography test is optimized.Waters Atlantis C18(150×3.9mm,5?m)is adopted as chromatographic column.With the solution of methanol:water solution=60:40 as mobile phase,the detection wavelength is 280nm.And the flow rate is 1.0mL/min.The extraction process is optimized.The effect on extraction rate of the extraction solvent and ultrasonic time is researched.As a result,when the methanol is adopted as extraction solvent and the ultrasonic time is 20min,the efficiency of extraction is highest.The linear relationship between hydroquinone and phenol,the precision and the recovery rate can satisfy the requirements of measurement.The result is satisfying.The method of use chromatography-diode array detector with high performance is established to determine the content of metronidazole and chloramphenicol in the cosmetic with the function of anti-acne and clearing mite.Waters Atlantis C18(150mm×3.9mm,5?m)is adopted as chromatographic column.With the solution of 0.01mol/L oxalic acid solution(adjusted pH=2.0 phosphate aqueous solution):methanol:acetonitrile=67:11:22 as mobile phase,the detection wavelength is 268nm.The flow rate is 0.8mL/min.The research on the extraction technology is conducted.The effect on extraction rate of the extraction solvent and ultrasonic time is researched.As a result,when the methanol:0.lmol/L hydrochloride=1:1 mixed solution is adopted as extraction solvent,the effect is ideal.And when the ultrasonic time is 25min,the efficiency of extraction is highest.The result of survey on this technology is good enough to meet the requirements.The method of atomic absorption spectrometry and atomic fluorescence spectrometric are adopted to determine the content of harmful heavy metals in the cosmetics.Four digestion methods are compared.Finally Microwave digestion method is adopted to treat the cosmetic.The research on factors such as digestion method,digestion reagent and air pressure is conducted.The research result shows that the digestion result and recovery rate are better when the digestion reagent is nitric acid-hydrogen peroxide system with 2 min digestion time and 0.5Mpa air pressure,3 min digestion time and 1.5Mpa air pressure,5 min digestion time and 1.5Mpa air pressure.After the comparison between different determination methods on heavy metal elements,graphite furnaee atomie absorption speetrophotometry is adopted to determine the content of lead,cadmium and chromium.Flame atomic absorption spectroscopy is adopted to determine the content of copper.The content of mercury and arsenic is determined by the method of atomic fluorescence spectrometry.The linear relationship,precision and recovery rate of the 6 heavy metals meet the requirements for the determination.The result is satisfying.