高效液相色谱法测定粮食制品中甲醛残留量

Determination of residual formaldehyde in grain foods by high-performance liquid chromatography

研究建立了一种用HPLC测定粮食制品中甲醛残留量的分析方法。样品中甲醛经60℃水浴提取,与2,4 二硝基苯肼衍生后,生成的2,4 二硝基苯腙经石油醚萃取净化,用HPLC DAD分离测定,外标法定量。最小检出质量浓度为5×10-11g,对于5g样品,最低检出量为0.01mg kg,样品回收率>80%,相对标准偏差≤10%,能满足残留量分析的要求。

A method for determination of residual formaldehyde in grain foods was established using high-performance liquid chromatography with DAD detector. The formaldehyde was extracted with water in 60 ℃ water-bath, reacted with 2,4-dinitrophenylydrazine(DNP) to form the hydrazone, then the hydrazone was extracted with petroleum ether. The extract was evaporated in a rotary evaporator using a 50～60 ℃ water-bath and the volume was adjusted to 5 mL with methanol. HPLC separations were conducted using a hypersil C_(18) (125 mm×4.0 mm, 5 μm) column, and using methanol-0.01 mol/L ammonium acetate(80∶20) as the mobile phase and the detection was made at the wavelength of 354 nm. The proposed method showed a detection limit of 5×10^(-11) g, recovery of more than 80% and RSD of less than 10%.