Ling Yu, Gao Zhong Feng, Zhou Qian, Li Nian Bing, Luo Hong Qun
Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), School of Chemistry and Chemical Engineering, Southwest University , Chongqing 400715, PR China.
Anal Chem. 2015 Feb 3;87(3):1575-81. doi: 10.1021/ac504023b. Epub 2015 Jan 22.
A multidimensional optical sensing platform which combines the advantages of resonance Rayleigh scattering (RRS), fluorescence, and colorimetry has been designed for detection of heparin. Phloxine B, a fluorescein derivative showing the special RRS spectrum in the long wavelength region, was selected to develop an easy-to-get system which can achieve switch-on sensing to obtain high sensitivity. The noise level of RRS in the long wavelength region is much weaker, and the reproducibility is much better; in this way, the sensitivity and selectivity can be improved. In the absence of heparin, the phloxine B and polyethyleneimine (PEI) form a complex through electrostatic interaction. Thus, the RRS signal at 554 nm is low; the phloxine B fluorescence is quenched, and the absorption signal is low. In the presence of heparin, competitive binding occurred between phloxine B and heparin toward PEI; then, phloxine B is gradually released from the phloxine B/PEI complex, causing obvious enhancement of the RRS, fluorescence, and absorption signals. Besides, the desorption of phloxine B is less effective for the heparin analogues, such as hyaluronic acid and chondroitin sulfate. In addition, the system presents a low detection limit of heparin to 5.0 × 10(-4) U mL(-1) and can also be applied to the detection of heparin in heparin sodium injection and 50% human serum samples with satisfactory results. Finally, the potential application of this method in reversible on-off molecular logic gate fabrication was discussed using the triple-channel optical signals as outputs.
一种结合了共振瑞利散射（RRS）、荧光和比色法优点的多维光学传感平台已被设计用于检测肝素。选择了在长波长区域呈现特殊RRS光谱的荧光素衍生物玫瑰红B，以开发一种易于获得的系统，该系统可实现开启传感以获得高灵敏度。长波长区域的RRS噪声水平要弱得多，重现性也更好；通过这种方式，可以提高灵敏度和选择性。在没有肝素的情况下，玫瑰红B和聚乙烯亚胺（PEI）通过静电相互作用形成复合物。因此，554nm处的RRS信号较低；玫瑰红B荧光被猝灭，吸收信号也较低。在有肝素存在的情况下，玫瑰红B和肝素对PEI发生竞争性结合；然后，玫瑰红B逐渐从玫瑰红B/PEI复合物中释放出来，导致RRS、荧光和吸收信号明显增强。此外，玫瑰红B的解吸对肝素类似物（如透明质酸和硫酸软骨素）效果较差。此外，该系统对肝素的检测限低至5.0×10(-4) U mL(-1)，还可应用于肝素钠注射液和50%人血清样品中肝素的检测，结果令人满意。最后，讨论了该方法在以三通道光信号作为输出的可逆开关分子逻辑门制造中的潜在应用。
