Studies Of Determination Method For Ultraviolet Light Stabilizers In Food Packaging Of Plastic Materials

Recently, the safety of food packaging materials have been drawing increasing attention all over the world, meanwhile, it also been taken as the technical trade measure to improve the threshold of imported food in some developed countries. Therefore, it is useful to develop methods to detect harmful chemicals in food packaging materials.Plastic products are commonly and widely used as food packaging materials. In order to improve the properties and functions of plastic, small molecular compounds (eg. plasticizer, stabilizer) are added in the machining process. When those additives contact with food, some toxic or harmful chemicals maybe migrate into food by permeating, absorbing, dissolving and so on. As a kind of anti-aging additive, ultraviolet light stabilizer is widely applied in plastic packaging materials to absorb ultraviolet radiation without the occurrence of photochemical reactions. Therefore, plastic packaging can withstand longer sunlight, and its service life will be prolonged. According to national mandatory standard GB 9685-2008, the quantity of the stabilizers materials should be controlled in a limited scale for some of those additives are poisonous and harmful to human beings. However, there have been no reports concerning the study of detection method for ultraviolet light stabilizers in food packaging materials.In the presenting dissertation, we chose nine ultraviolet light stabilizers (UV-0,UV-2,UV-24,UV-3,UV-71,UV-9,UV-326,UV-327,UV-531) as the research object according to GB 9685-2008. It's worth noting that a new high performance liquid chromatographic (HPLC) method was firstly developed for the determination of those nine ultraviolet light stabilizers simultaneously after the optimization of a series of experimental parameters of sample preparation and HPLC analytical conditions. The samples were extracted with the assistant of ultrasound, concentrated under reduced press and then further dissolved in methanol before cleaning up with solid phase extraction column. The resulting mixture was treated under a stream of nitrogen at 40℃and redissolved with constant volume of methanol.C18 chromatographic column was chose for the HPLC separation and detected at the wavelength of 310 nm using the external standard method as quantitative analysis. The results indicated that the calibration curves had good linearity, especially, their average recoveries of three added concentration levels were satisfactory. The procedure is mild and easy to handle, and satisfies well with the request of detecting permitted quantity of light stabilizers in food packaging of plastic materials by good repeatability and highly sensitivity, which provides valuable technical support for the further research of ultraviolet light stabilizers in our country.