Baudry J, Rouzeau C, Goubault C, Robic C, Cohen-Tannoudji L, Koenig A, Bertrand E, Bibette J
Laboratoire Colloïdes et Matériaux Divisés, Unité Mixte de Recherche 7612, Université Pierre et Marie Curie, CNRS-Ecole Supérieure de Physique et de Chimie Industrielles, 10 Rue Vauquelin, F-75005 Paris, France.
Proc Natl Acad Sci U S A. 2006 Oct 31;103(44):16076-8. doi: 10.1073/pnas.0607991103. Epub 2006 Oct 18.
When ligands and receptors are both attached on surfaces, because of the restriction of configurational freedom, their recognition kinetics may be substantially reduced as compared with freely diffusing species. In nature, this reduction may influence the efficiency of the capture and adhesion of circulating cells. Here we show that similar consequences are observed for colloids grafted with biomolecules that are used as probes for diagnostics. We exploit Brownian magnetic colloids that self-assemble into linear chains to show also that the resulting one-dimensional confinement considerably accelerates the recognition rate between grafted receptors and their ligands. We propose that because confinement significantly augments the colliding frequency, it also causes a large increase in the attempt frequency of the recognition. This work gives the basis of a rapid, homogeneous, and highly sensitive bioanalysis method.
当配体和受体都附着在表面时，由于构象自由度的限制，与自由扩散的分子相比，它们的识别动力学可能会大幅降低。在自然界中，这种降低可能会影响循环细胞的捕获和黏附效率。在此，我们表明，对于接枝有生物分子并用作诊断探针的胶体，也会观察到类似的结果。我们利用自组装成线性链的布朗磁性胶体，还表明由此产生的一维限制显著加速了接枝受体与其配体之间的识别速率。我们提出，由于限制显著增加了碰撞频率，它还会导致识别尝试频率大幅提高。这项工作为一种快速、均相且高度灵敏的生物分析方法奠定了基础。
