synthesis of polyoxometalate-rgo composite coated on the inner wall of stainless steel tube as a sorbent for extraction of some selected parabens through determination by hplc-uv

Parabens are one of the harmful components of cosmetic products, which can affect the safety of cosmetic products. moreover the concentration of parabens have to be controlled [1]. therefore, an appropriate method should be developed to determine the concentration of parabens in the cosmetic samples. here in, a new sorbent based on the combination of poms with rgo have been synthesized. the prepared sorbent has been used for the extraction of the selected analyte. the extracted analytes were eluted by an appropriate eluent and analyzed by hplc–uv. to perform the extraction method, the prepared sorbent has been accommodated on the inner surface of the stainless steel tube and the sample solution was passed through the sorbent. the extraction was performed by flow injection analysis method. finally, the extracting device was used for the extraction and determination of parabens in different types of cosmetic samples. the obtained results indicated that the sorbent is appropriate for the extraction of parabens from cosmetic. optimization of extraction factors was done using univariate optimization method. under optimal conditions, rsds of intra-day and inter-day standards was less than 4% and 6.8% for samples, respectively. this method was successfully used to determine some parabens in various cosmetic products.