Hair Dyes Phthalaldehyde Amines Separation And Analysis Of Heavy Metals And Several Trace Element Determination Method

This thesis focuses on the analysis determination of various sold hair dyes. P-phenylenediamine,m-phenylenediamine,hydroquinone and resorcinol were separated and analyzed to find the best conditions which were widely used in oxidation hair dyes. The determination method of 2-hydroxyl-1,4-naphthoquinonein in emerging plant hair dyes was established. Moreover, the trace heavy metal elements possibly contained in plant hair dyes were determined. This study has practical significance in hair dye quality control and reduces health risks of consumers.The major results of this thesis are outlined as follows:1. A HPLC method for the simultaneous separation and determination of p-phenylenediamine,m-phenylenediamine,hydroquinone and resorcinol in four kinds of oxidizing hair dyes was established. Using this method for analyzing samples, the detection limit of the four substances are1.2,0.6,0.4 and 0.8μg·mL-1 respectively. The four substances can be separate within 25 min. This analysis method has high accuracy and good repeatability. It can be used for quality control of p-phenylenediamine,m-phenylenediamine,hydroquinone and resorcinol in oxidation hair dye.2. A HPLC method for the rapid separation and determination of 2-hydroxyl-1,4-naphthoquinonein in eight kinds of plant hair dyes was developed. Detecting wavelength and mobile phase ratio affecting the result were discussed and the suitable chromatographic separation conditions were selected. The extraction solvent and extracting mode were studied. Using methanol-ultrasonic extraction and under the selected chromatographic separation condition, the content of 2-hydroxyl-1,4-naphthoquinonein in the samples can be determined.3. Apparatus conditions of GFAAS for determination of Pb. Cd and Cu in eight kinds of plant hair dyes were inquired. The factors affecting the result were investigated including the drying temperature, atomization temperature, ashing temperature and matrix modifier. The microwave digestion conditions of samples pretreatment were investigated by orthogonal experiment. The optimum digestion conditions are:sample/solution (g/ml) 1:12, HNO3/H2O2 (V/V) 4:1, the digestion time 5 min and the microwave pressure 1.5 MPa. The precision and recovery experiment results show that the relative standard deviations of Pb,Cd and Cu were below 5% and the average recovery rate were between 95% and 110%.This method is rapid, accurate, low acid consumption so it is suitable for rapid determination of trace elements in plant hair dye.