Kamra Tripta, Chaudhary Shilpi, Xu Changgang, Montelius Lars, Schnadt Joachim, Ye Lei
Division of Synchrotron Radiation Research, Department of Physics, Lund University, Box 118, 221 00 Lund, Sweden; Division of Pure & Applied Biochemistry, Lund University, Box 124, 221 00 Lund, Sweden.
Division of Pure & Applied Biochemistry, Lund University, Box 124, 221 00 Lund, Sweden.
J Colloid Interface Sci. 2016 Jan 1;461:1-8. doi: 10.1016/j.jcis.2015.09.009. Epub 2015 Sep 5.
One challenging task in building (bio)chemical sensors is the efficient and stable immobilization of receptor on a suitable transducer. Herein, we report a method for covalent immobilization of molecularly imprinted core-shell nanoparticles for construction of robust chemical sensors. The imprinted nanoparticles with a core-shell structure have selective molecular binding sites in the core and multiple amino groups in the shell. The model Au transducer surface is first functionalized with a self-assembled monolayer of 11-mercaptoundecanoic acid. The 11-mercaptoundecanoic acid is activated by treatment with carbodiimide/N-hydroxysuccinimide and then reacted with the core-shell nanoparticles to form amide bonds. We have characterized the process by studying the treated surfaces after each preparation step using atomic force microscopy, scanning electron microscopy, fluorescence microscopy, contact angle measurements and X-ray photoelectron spectroscopy. The microscopy results show the successful immobilization of the imprinted nanoparticles on the surface. The photoelectron spectroscopy results further confirm the success of each functionalization step. Further, the amino groups on the MIP surface were activated by electrostatically adsorbing negatively charged Au colloids. The functionalized surface was shown to be active for surface enhanced Raman scattering detection of propranolol. The particle immobilization and surface enhanced Raman scattering approach described here has a general applicability for constructing chemical sensors in different formats.
构建（生物）化学传感器面临的一项具有挑战性的任务是将受体高效且稳定地固定在合适的换能器上。在此，我们报道了一种用于共价固定分子印迹核壳纳米粒子以构建坚固化学传感器的方法。具有核壳结构的印迹纳米粒子在核内具有选择性分子结合位点，在壳层具有多个氨基。首先用11 - 巯基十一烷酸的自组装单分子层对模型金换能器表面进行功能化。通过用碳二亚胺/ N - 羟基琥珀酰亚胺处理激活11 - 巯基十一烷酸，然后使其与核壳纳米粒子反应形成酰胺键。我们通过使用原子力显微镜、扫描电子显微镜、荧光显微镜、接触角测量和X射线光电子能谱研究每个制备步骤后的处理表面来表征该过程。显微镜结果表明印迹纳米粒子成功固定在表面。光电子能谱结果进一步证实了每个功能化步骤的成功。此外，通过静电吸附带负电荷的金胶体激活MIP表面的氨基。功能化表面显示出对普萘洛尔的表面增强拉曼散射检测具有活性。本文所述的粒子固定和表面增强拉曼散射方法对于构建不同形式的化学传感器具有普遍适用性。
