Muller-Renaud Stéphanie, Dupont Didier, Dulieu Philippe
INRA, Unité de Recherches en Technologie et Analyses Laitière, Place du Champ de Foire, F-39800 POLIGNY, France.
J Dairy Res. 2005 Feb;72(1):57-64. doi: 10.1017/s0022029904000664.
An immunoassay to quantify alphas1-casein (alphas1-CN) in milk using an optical biosensor, based on surface plasmon resonance (SPR) measurement, has been developed. The assay consists of a two-step sandwich strategy, with two anti-alphas1-CN antibodies directed against each extremity of the molecule. This strategy permits only intact alphas1-CN to be quantified and not its degradation products. The calibration curve was obtained using a reference milk powder with a known alphas1-CN concentration. Analysis time per sample was less than ten minutes. The antibody-coated surface could be used for more than 150 determinations. Detection limit was established at 0.87 microg/ml and the intra- and inter-assay variation coefficients were 2.86 and 5.31%, respectively. The method was applied to raw milk to quantify intact alphas1-CN, with no pretreatment of the sample. An initial analysis of 48 milk samples permitted alphas1-CN concentrations ranging from 8.8 to 12.06 mg/ml to be obtained.
已开发出一种基于表面等离子体共振（SPR）测量的光学生物传感器免疫分析法，用于定量牛奶中的αs1-酪蛋白（αs1-CN）。该分析采用两步夹心策略，使用两种针对该分子两端的抗αs1-CN抗体。这种策略仅允许对完整的αs1-CN进行定量，而不是其降解产物。使用已知αs1-CN浓度的参考奶粉获得校准曲线。每个样品的分析时间不到十分钟。抗体包被的表面可用于150多次测定。检测限设定为0.87微克/毫升，批内和批间变异系数分别为2.86%和5.31%。该方法应用于原料奶，无需对样品进行预处理即可定量完整的αs1-CN。对48个牛奶样品的初步分析得到的αs1-CN浓度范围为8.8至12.06毫克/毫升。
