| Launch：2022-05-19 |
As one of the consumer goods closely related to people's daily lives, skin care parties have begun to pay more attention to the ingredients of skin care products, and preservatives, as an ingredient that allows products to be stored for a longer time, are inevitable in skin care products. So skin care products contain preservatives, can they still be used? Let's take a look at it with author.
防腐剂的作用和种类
Preservatives in cosmetics, skin care products the main role is to prevent the growth of microorganisms, to maintain the nature of the product is stable and not easy to deteriorate after the use of the lid, therefore, most of the skin care products in the formula, more or less will add one or more kinds of preservatives, to prevent bacteria, mold in it multiply.
Although preservatives have a good effect on inhibiting and killing various bacteria in cosmetics, they also have potential side effects on the human body, so they are listed as restricted substances by the regulations on cosmetics management in many countries. There are 6 types of preservatives most commonly used in skin care products.
Summarized it into the following table:
Acids | Benzoic acid, sodium benzoate, sorbic acid, salicylic acid, etc | Mild in nature, it is mostly used in exfoliating, salicylic acid gels and other products |
Phenols | Phenoxyethanol, phenethyl alcohol, benzyl alcohol | Phenethyl alcohol is not a preservative type in Japan, and benzyl alcohol is listed as a flavor allergen in the European Union; phenoxyethanol is a solvent and preservative, which is relatively mild |
Formaldehyde emission class | Imidazolylurea, diimidazolidinylurea, etc | During the dissolution process, a trace amount of formaldehyde is released, which is used for sterilization and antiseptics, maintaining the freshness of cosmetics |
Parabens | Methyl hydroxybenzoate, ethyl parahydroxybenzoate, butyl parahydroxybenzoate, etc | Skin allergies are the least caused and are therefore considered the safest in most countries. |
Isothiazolinones | Toluene isothiazolinone, methylchloroisothiazolinone | The probability of triggering skin allergies is the highest, and it is the most likely to cause contact dermatitis |
Iodopropynyl butylcarbamate | / | It is mild, but it is more irritating to the mucous membrane, so avoid the periphery of the lips when using |
Knowing the true face of preservatives, is it not that the misunderstanding of preservatives is not so deep? Skin care products contain preservatives, but also can be used, of course, provided that the amount of additions meets the hygienic norms, then, how to detect preservatives in skin care products?
SERS technology determines both preservatives simultaneously
The analysis and detection of prohibited and restricted ingredients in cosmetics is of great significance for monitoring the quality of cosmetics and ensuring the safety of consumers. Recently, through surface enhanced Raman scattering (Surface-Enhanced Raman Scattering, referred to as SERS) technology, we have simultaneously detected two substrates sorbic acid and benzoic acid preservatives in toner and lotion, and through simple, fast and low-cost pretreatment operations, we eliminate the interference of skin care matrix, and effectively extract and enrich the targets of sorbic acid and benzoic acid at the same time. Raman signal enhancement was performed on both preservatives by colloidal silver nanoparticles and auxiliary agglomeration enhancement reagents.Firstly, we conducted Raman enhancement tests on benzoic acid and sorbic acid standards to determine their characteristic peaks, and from the SERS spectrogram results (Fig.1), it can be seen that the raman characteristic peak of benzoic acid is 1001cm-1, 840cm-1, and the raman characteristic peak of sorbate is 1645cm-1, 1158cm-1.
Fig.1 Benzoic acid SERS spectra of the sorbic acid standard
For toner, emulsion sorbic acid respectively carried out different concentrations of standardization before the treatment to enhance the detection, the detection results of the spectrum as shown in Fig 2、3, water, milk two substrates sorbate Raman characteristic peak response is obvious, blank without false positive interference; because skin care products usually add more than one preservative, more preservatives at the same time there are certain difficulties, we add 0.2% benzoic acid, 0.5% sorbic acid in the toner at the same time, as shown in Fig.4, benzoic acid 1001cm-1, 840cm-1, sorbic acid 1645cm-1, 1158cm-1 Raman characteristic peak response is obvious, blank samples have no false positive, indicating that the method can detect benzoic acid and sorbic acid in skin care products at the same time.
Fig.2 SERS spectra of toner sorbate
Fig. 3 Emulsion sorbate SERS spectra
Fig. 4 Benzoic acid in toner sorbic acid simultaneous detection of SERS spectra
I believe that everyone has understood that the addition of preservatives is not terrible, and excessive addition will cause potential dangers, so the rapid, portable, low-cost and high-specific detection of preservatives in skin care products is of vital significance. The above experimental results show that according to the above experimental data, it can be seen that the method of rapid screening of acid preservatives in cosmetics can be carried out through SERS technology, and the Raman spectroscopy equipment and SERS method independently developed by Oceanhood can provide an efficient analysis method for the detection of preservatives in skin care products, and escort the quality monitoring of cosmetics.
Portable Raman for fast operation
Independent research and development, support domestic production
High stability, many customers choose
Signal enhancement bracket, the detection effect is remarkable
The enhancement effect is remarkable, suitable for high-volume experiments
The reagent is stable in nature and long-lasting
Particle size control, strong versatility
