Ingwersen S H
Novo Nordisk A/S, Maaloev, Denmark.
Biomed Chromatogr. 1993 May-Jun;7(3):166-71. doi: 10.1002/bmc.1130070314.
A combination of reversed phase and anion exchange solid phase extraction (SPE) was investigated for the liquid chromatographic assay of the neuroprotectant agent NBQX in human plasma and urine. Reversed phase SPE alone using a variety of phases failed to yield sufficiently pure extracts for the assay of plasma in the low ng/mL concentration range using UV detection. However, using Bond Elut Certify II SPE columns containing a mixture of reversed phase and anion exchange functionalities markedly improved the purity of plasma extracts. Furthermore, a change of detector wavelength from UV (294 nm) to the visible region (380 nm) removed some minor interfering peaks originating from plasma. Using optimized SPE conditions with an extraction recovery of 92.3% and a high performance liquid chromatographic procedure with Lichrospher C18 as the stationary phase, the lower limit of quantitation in human plasma was 2 ng/mL (corresponding to 0.75 ng injected on-column). Intra-assay coefficients of variation ranged from 9.6% at 2 ng/mL to 1.3% at 10 ng/mL. A similar SPE procedure was applied to human urine with acceptable recovery (88.3%), but an analytical column of different selectivity (Chromspher B C18) was necessary in order to avoid interference from the urine. The limit of quantitation for the urine assay was 25 ng/mL and the intra-assay precision ranged from 4.6% at 25 ng/mL to 2.2% at 500 ng/mL.
研究了反相和阴离子交换固相萃取（SPE）相结合的方法，用于在人血浆和尿液中对神经保护剂NBQX进行液相色谱分析。单独使用各种反相SPE柱，在低纳克/毫升浓度范围内使用紫外检测时，无法获得足够纯的血浆提取物用于分析。然而，使用含有反相和阴离子交换功能混合物的Bond Elut Certify II SPE柱，显著提高了血浆提取物的纯度。此外，将检测波长从紫外（294纳米）改为可见光区域（380纳米），去除了一些源自血浆的微小干扰峰。使用优化的SPE条件，萃取回收率为92.3%，并采用以Lichrospher C18为固定相的高效液相色谱法，人血浆中的定量下限为2纳克/毫升（相当于柱上进样0.75纳克）。批内变异系数在2纳克/毫升时为9.6%，在10纳克/毫升时为1.3%。类似的SPE方法应用于人尿液，回收率可接受（88.3%），但为了避免尿液干扰，需要使用不同选择性的分析柱（Chromspher B C18）。尿液分析的定量下限为25纳克/毫升，批内精密度在25纳克/毫升时为4.6%，在500纳克/毫升时为2.2%。
