Koesukwiwat Urairat, Jayanta Siripastr, Leepipatpiboon Natchanun
Chromatography and Separation Research Group, Department of Chemistry, Faculty of Science, Chulalongkorn University, Bangkok 10330, Thailand.
J Chromatogr A. 2007 Jan 26;1140(1-2):147-56. doi: 10.1016/j.chroma.2006.11.099. Epub 2006 Dec 20.
A multiresidue method suitable for confirmation and determination of six sulfonamides (SAs), three tetracyclines (TCs), and pyrimethamine (PYR) in cow milk was validated. Milk samples were extracted using copolymer Oasis HLB solid-phase extraction (SPE) and analyzed by liquid chromatography-electrospray mass spectrometry with positive ion mode. Estimated method detection limits (MDL) and method quantitation limits (MQL) ranged from 0.48 to 2.64 and 0.61 to 8.64ng/mL, respectively. These values are far lower than the maximum residue limits (MRLs) established by several control authorities. Excellent linear dynamic range was observed from the method quantitation limits to 300ng/mL with correlation coefficients better than 0.9900 for all compounds. The method was accurate with recoveries ranging from 72.01 to 97.39%. Good intra-precision and intermediate precision were obtained with RSD better than 11.08%. The method is fairly robust with sample pH being the only critical control point.
验证了一种适用于牛奶中六种磺胺类药物（SAs）、三种四环素类药物（TCs）和乙胺嘧啶（PYR）确证与测定的多残留方法。牛奶样品采用共聚物Oasis HLB固相萃取（SPE）进行提取，并通过液相色谱 - 电喷雾质谱在正离子模式下进行分析。估计的方法检出限（MDL）和方法定量限（MQL）分别为0.48至2.64 ng/mL和0.61至8.64 ng/mL。这些值远低于多个监管机构规定的最大残留限量（MRLs）。从方法定量限到300 ng/mL观察到了出色的线性动态范围，所有化合物的相关系数均优于0.9900。该方法准确，回收率在72.01%至97.39%之间。获得了良好的批内精密度和中间精密度，相对标准偏差（RSD）优于11.08%。该方法相当稳健，样品pH是唯一的关键控制点。
