A Study And Improvement On Determining Preservatives In Personal Care Products

With the rapid development of national economy and the continuous improvement of people’s living standards,cosmetics have become an indispensable necessity in people’s daily life.In general,cosmetics can be divided into washing cosmetics and beauty cosmetics two broad categories.Washing cosmetics can be used to clean the skin,beauty cosmetics can be used to beautify the appearance and anti-aging and so on.Under the action of physics,Chemistry and microbe,the rich protein and carbohydrate in cosmetics may lose the original color,smell,taste and shape and go bad.Therefore,in order to maintain the quality of cosmetics products,cosmetics will generally add one or more preservatives to inhibit bacteria or kill bacteria.However,the excessive use of preservatives will often bring people a variety of health hazards.Therefore,it is necessary to study the preservatives in cosmetics in order to guide people’s Daily Life Selection and provide a theoretical basis for the improvement of market quality control.Based on the author’s actual work,this paper mainly does the following research:1.The effect of traditional agitation pretreatment methods,ultrasound-assisted extraction and microwave assisted extraction on the recovery of phenoxyethanol and salicylic acid in personal care products were investigated.Finally,pure methanol was selected as solvent and ultrasonic-assisted extraction at 30 ℃ for 30 minutes was used as pretreatment method.2.The effect of reversed-phase high performance liquid chromatography,gas chromatography and gas chromatography-mass spectrometry on the recovery of phenoxyethanol content in personal care product was compared.The conclusion was that a gradient elution with water and methanol would be used as the mobile phase when determined phenoxyethanol in personal care products by HPLC.The precision and recovery rate of the method are good,the retained time of the phenoxyethanol elution is less,and the peak can be obtained in 3.2 minutes,which greatly improves the detection efficiency.3.To study the effect of mobile phase ratio and elution method on salicylic acid recovery rate when HPLC was used to measure the content of salicylic acid in personal care products.The experimental data proved that 0.02mol/L potassium dihydrogen phosphate-methanol(50:50,pH3.5)system was used as the mobile phase,and the isocratic elution method was adopted.The peaking state and separation effect of salicylic acid were good,and the precisions,repeatability and recovery rate of the method all met requirements.