Vikholm-Lundin Inger, Pulli Timo, Albers Willem M, Tappura Kirsi
VTT Technical Research Centre of Finland, P.O. Box 1300, FI-33101 Tampere, Finland.
Biosens Bioelectron. 2008 Dec 1;24(4):1042-4. doi: 10.1016/j.bios.2008.06.049. Epub 2008 Jul 9.
Recombinant anti-morphine Fab' fragments have been immobilised on gold by covalent attachment through the free thiol groups of the fragment. The antibody fragments were intercalated with a non-ionic hydrophilic polymer in order to suppress non-specific binding of interfering substances. The antibodies are oriented on the surface due to the thiol groups of the antibody and the layer shows a high response to antigen. Non-specific binding of bovine serum albumin is moreover very low because of the repellent polymer. Synthetic receptors composed of an imprinted self-assembled monolayer made from lipoates and the template, morphine, exhibit the same binding response to the antigen, morphine as the site-specific oriented antibody monolayer. A similar binding curve could be obtained as that for binding of morphine to an antibody Fab' fragment/polymer layer - indicating that synthetic receptors produced are comparable to those of antibody layers. Concentrations down to 0.1ng/ml have been measured with surface plasmon resonance.
重组抗吗啡Fab'片段已通过片段的游离巯基共价连接固定在金上。抗体片段与非离子亲水性聚合物插层，以抑制干扰物质的非特异性结合。由于抗体的巯基，抗体在表面呈定向排列，该层对抗原有高响应性。此外，由于聚合物的排斥作用，牛血清白蛋白的非特异性结合非常低。由硫辛酸和模板吗啡制成的印迹自组装单分子层组成的合成受体，对吗啡抗原的结合反应与位点特异性定向抗体单分子层相同。可获得与吗啡与抗体Fab'片段/聚合物层结合相似的结合曲线——表明所产生的合成受体与抗体层的受体相当。通过表面等离子体共振已测量到低至0.1ng/ml的浓度。
