ABSTRACT
A method using high performance liquid chromatography with diode array detection coupled with fluorescence detection was applied to determine four polycyclic aromatic hydro carbons in anthracene oil for toys. This method showed good abilities of the baseline separation and high sensitivity under the optimized analytical conditions. The limits of the fluorescence detection were 0.5 - 1000 microg/L, while the limits of the diode array detection were 0.5 - 1 000 mg/L. The precisions of the method were 0.7% - 8.8%. The recoveries of the standard samples were 70.0% - 120%. The limits of detection (LOD) of anthracene, pyrene, phenanthrene and fluoranthene were 0.1, 0.1, 0.2 and 0.3 microg/L, and the limits of quantitation (LOQ) of the four substances were 0.4, 0.2, 0.5 and 0.8 microg/L, respectively. In comparison with other methods, the method has higher detection speed and lower detection limits, which is useful to analyze rapidly those four polycyclic aromatic hydrocarbons in anthracene oil for toys.
ABSTRACT
A comprehensive analytical method based on high performance liquid chromatography (HPLC) has been developed for the determination of 12 sunscreen agents in cosmetics. The cosmetic samples were extracted by methanol. The target compounds were separated on an SB-C8 column (250 mm x 4.6 mm, 5 microm) in gradient elution mode using methanol and 0.1% (v/v) formic acid aqueous solution as mobile phases. The detective wavelength was 311 nm. The linear plots were obtained between 1.0 and 500 mg/L with good correlation coefficients larger than 0.999 5. The limits of detection (LODs) for this method were in the range of 0.002 -0.1 mg/L. The spiked recoveries of commercial cosmetics were in the range of 97.4% - 107.5% with the relative standard deviations of 1.54% -4.98%. The results indicated that the developed method is simple, rapid, accurate and suitable for the determination of 12 sunscreen agents in cosmetics samples.
Subject(s)
Chromatography, High Pressure Liquid/methods , Cosmetics/analysis , Sunscreening Agents/analysisABSTRACT
The analytical method of melamine in milk and milk powder by high performance liquid chromatography (HPLC) was established. The sample was purified by a cation exchange solid-phase extraction column, separated on a Diamonsil C18 column (4.6 mm x 200 mm, 5 microm) with acetonitrile-0.01 mol/L sodium heptanesulfonate (pH 3.3) (10:90, v/v) as mobile phase at a flow rate of 1.0 mL/min, and determined by a photodiode array detector. A linear calibration curve was obtained in the concentration range of 1 - 500 mg/L. The qualification limit was 0.2 mg/kg, and the quantification limit was 1 mg/kg. The recovery was 81.4% -83.7%.