DEVELOPMENT AND VALIDATION METHOD OF ANALYSIS FORMALDEHYDE IN CREAM COSMETIC CONTAIN FORMALDEHYDE RELEASER

• Main Author: Yuniati, Wiwiet
• Format: Theses
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/52309
• Institution: Institut Teknologi Bandung

Formaldehyde releasers such as diazolidinyl urea and imidazolidinyl urea are the most widely used preservatives in cosmetics. However, despite these components commonly used in cleansing and skin care cosmetics products, it also potentially might cause allergies (allergens) when used more than requirement. According to The International Agency for Research on Cancer (IARC) in 2006, these compound classified into group I as a human carcinogen based on evidence that formaldehyde causes nasopharyngeal cancer and myeloid leukemia. Therefore, in order to meet safety, efficacy and quality requirements for cosmetics, which particularly used formaldehyde releasers, it is important to analyze these products using the latest, sensitive and validated analytical method. This method should have the characteristics for identifying and quantitatively determining the levels of formaldehyde released from preservatives used in cream cosmetic. There are already standard methods to analyze the levels of formaldehyde released from the formaldehyde releaser class of preservatives in cream cosmetic skin care products, however further modifications are needed in order to update technology advancement and regulations. A modified analysis methods using gas chromatography mass spectrometry (GC MS) and gas chromatography flame ionization detector (GC FID) have been developed and validated to determine the levels of formaldehyde released from the formaldehyde releaser class of preservatives in cream cosmetic products. The analysis method was carried out by derivatization technique using paratoluensulfonic acid in ethanol, then formaldehyde compounds in the sample and ethanol with paratoluensulfonic acid as catalyst reacted to produce diethoxymethan compounds with ion masses m/z 31.0; 59.0 and 103.0. The development of this method uses the OFAT (One Factor at a Time) method optimization for the following variables: elution technique and mobile phase flow rate; column type as stationary phase; the concentration of derivatized solutions, namely paratoluensulfonic acid in ethanol (acidified ethanol) used; as well as temperature and incubation time which produce optimal peak response and meet the acceptance requirements. The results of the optimization of the elution technique and flow rate provide optimal peak response with an initial temperature program of 34 o C for 15 minutes, followed by an increase of 40 o C/minute until a temperature of 220 o C is reached and held for 5 minutes; and the flow rate is set at 0.8 mL / min. Optimization of the type of column (stationary phase) used were non-polar capillary column 1MS, 5MS and polar Wax column (polyethylenglicol 100%) with a column length of 30 m, an internal diameter of 0.25 µm and a film thickness of 0.25 µm indicated that the nonpolar column 1MS and 5MS produced a peak response with a tailing factor (Tf) greater than 1.4 because there were other peaks that were not separated, while the polar wax column produced a peak response with a Tf that met the requirements, namely 0.975; and a capacity factor of 0.7 so that in the subsequent testing process a wax column with a film thickness of 0.5 µm was used in order to obtain a capacity factor value of 1 < k' <10. Optimization of the concentration of paratoluensulfonic acid solution in ethanol was carried out in five series, namely 0.1; 0.5; 1.0; 1.5 and 2.0% and at a concentration of 1.0% the optimal peak response was obtained. Optimization of temperature and incubation time is carried out in other conditions which have been optimized to be fixed to produce a perfect reaction. The optimal peak response was obtained at 60 o C for 30 minutes. Sample analysis was also performed using High Performance Liquid Chromatography (HPLC) a diode-array detector (DAD) with derivatization of 2,4-dinitrophenylhydrazin as a reliable standard method for comparing calculation results. The validation process in the gas chromatography method's specificity test was also carried out by injecting compounds such as n-hexan, cyclohexan, formic acid and acetone, to find out that during the validation process it was not interferences by other compounds that may be present in the cream cosmetic matrix or as contaminants. Intraday and interday precision tests obtained levels and relative standard deviation (% RSD) respectively 101.28% and RSD 0.37% (HPLC DAD); 101.27% and 1.49% (GCMS); and 101.37% and RSD 1.24% (GC FID). The accuracy test (% recovery) obtained for the three methods was in the confidence interval (CI) of 95.0% - 105.0% and the detection and quantitation limits were 0.0099 µg/mL and 0.0329 µg/mL (HPLC); 0.0158 µg/mL and 0.0528 µg/mL (GCMS); and 1.1287 µg/mL and 3.7625 µg/mL (GC FID). The analytical method developed has met the validation requirements so that it can be applied for routine testing of cream cosmetic products containing the preservative formaldehyde releaser. The sample test results using a validated analytical method show that the six cream cosmetics meet the requirements for formaldehyde levels set in the 0.02% -0.08% level range.