Laboratory for Polymer Analysis, Biomedical Technology Wing, Sree Chitra Tirunal Institute for Medical Sciences & Technology, Poojapura, Trivandrum 695012, Kerala, India.
Anal Chim Acta. 2010 Mar 10;662(2):186-92. doi: 10.1016/j.aca.2010.01.007. Epub 2010 Jan 11.
A new method for the detection of C-reactive protein (CRP) in serum using functionalized gold nano-particles (GNP) is reported. The affinity towards CRP is imparted to GNP by tethering O-phosphorylethanolamine (PEA) onto their surface. GNP and modified GNP were characterized using TEM, particle size analysis, zeta potential measurements, absorption spectroscopy and FT-IR techniques. The event of binding of CRP onto the PEA-GNP is followed by visibly observable colour change. We observed a red shift as well as a decrease in absorption in the plasmon peak of the modified GNP with the concentration of CRP. When the concentration of CRP exceeded 450 ng mL(-1), particles were aggregated and the solution became turbid. The method exhibited a linear range for CRP from 50 to 450 ng mL(-1) with a detection limit of 50 ng mL(-1). The colour change and the variation in absorption of the GNP were highly specific to CRP even in the presence of albumin. We estimated CRP in blood serum collected from patients and the results obtained compared well with the estimation using the technique of nephelometry based on the antibody-antigen interaction.
本文报道了一种使用功能化金纳米粒子（GNP）检测血清中 C 反应蛋白（CRP）的新方法。通过将 O-磷酸乙醇胺（PEA）键合到其表面，赋予 GNP 对 CRP 的亲和力。使用 TEM、粒度分析、Zeta 电位测量、吸收光谱和 FT-IR 技术对 GNP 和修饰的 GNP 进行了表征。CRP 结合到 PEA-GNP 上的事件伴随着可见的颜色变化。我们观察到修饰的 GNP 的等离子体峰值的红移以及吸收的减少与 CRP 的浓度成正比。当 CRP 的浓度超过 450ng mL(-1)时，颗粒聚集，溶液变得混浊。该方法在 50 至 450ng mL(-1)之间对 CRP 表现出线性范围，检测限为 50ng mL(-1)。即使在白蛋白存在的情况下，GNP 的颜色变化和吸收变化也高度特异性地针对 CRP。我们估计了从患者血液中采集的血清中的 CRP，得到的结果与基于抗体-抗原相互作用的免疫比浊法的估计值非常吻合。
