Mascher Daniel G, Unger Christian P, Mascher Hermann J
Pharm-Analyt Labor GmbH, Ferdinand-Pichler-Gasse 2, 2500 Baden, Austria.
J Pharm Biomed Anal. 2007 Jan 17;43(2):691-700. doi: 10.1016/j.jpba.2006.08.008. Epub 2006 Sep 12.
The method for the simultaneous determination of neomycin and bacitracin in human or rabbit serum was developed by using ion pairing reversed phase chromatography and tandem mass spectrometry (MS/MS) detection with electrospray (ESI) in positive mode. Both substances elute under these conditions at the same time and also kanamycin as internal standard elutes almost at the same time. The sample preparation was simple-only using 0.1 mL serum by protein precipitation with acetonitrile. Neomycin and bacitracin were detected as two-fold charged ions as well as the internal standard. The calibration range of these quite difficult detectable substances was 0.2-50 microg/mL of serum. The method was validated for both human or rabbit serum. The inter batch precision of quality control samples in human serum for neomycin ranged from 4.46% to 8.99% and for bacitracin from 6.85% to 11.17%. The inter batch accuracy for neomycin ranged from 98.7% to 100.7% and for bacitracin from 99.2% to 103.0%. At lower limit of quantitation (LLOQ) level of 0.2 microg/mL inter batch precision in human serum for neomycin was 12.05% and for bacitracin 11.91%, whereas accuracies were 99.9% for neomycin and 102.7% for bacitracin. Bench top stability in human or rabbit serum was given over three freeze thaw cycles and 4h at room temperature. The method can be considered to be specific and recoveries for sample preparation were high.
采用离子对反相色谱法和串联质谱（MS/MS）检测（正模式电喷雾电离），建立了同时测定人或兔血清中新霉素和杆菌肽的方法。在这些条件下，两种物质同时洗脱，作为内标的卡那霉素也几乎同时洗脱。样品制备简单，仅用0.1 mL血清，通过乙腈沉淀蛋白。新霉素和杆菌肽以及内标均以二价离子形式被检测到。这些极难检测的物质的校准范围为血清中0.2 - 50 μg/mL。该方法在人血清和兔血清中均得到验证。人血清中质量控制样品新霉素的批间精密度为4.46%至8.99%，杆菌肽为6.85%至11.17%。新霉素的批间准确度为98.7%至100.7%，杆菌肽为99.2%至103.0%。在0.2 μg/mL的定量下限（LLOQ）水平，人血清中新霉素的批间精密度为12.05%，杆菌肽为11.91%，而准确度新霉素为99.9%，杆菌肽为102.7%。在人或兔血清中，经过三个冻融循环以及室温下4小时的台式稳定性良好。该方法可认为具有特异性，样品制备的回收率高。
