Hongzhi Lu, Shoufang Xu
School of Chemistry and Chemical Engineering, Linyi University, Linyi 276005, China.
School of Chemistry and Chemical Engineering, Linyi University, Linyi 276005, China.
Talanta. 2017 Apr 1;165:482-488. doi: 10.1016/j.talanta.2016.12.087. Epub 2017 Jan 1.
In this work, mesoporous structured molecularly imprinted ratiometric fluorescence sensor (M-R-MIPs) for highly sensitive and selective determination of bovine hemoglobin (BHb) was developed based on core-shell structure. First, red CdTe QDs were embedded into silica nanoparticles by reverse microemulsion method, then BHb imprinted silica shell were coated on the core silica. In order to improve the sensitivity of the as-prepared MIPs sensor, during the process of imprinted silica shell formation, functional monomer-template-QDs sandwich structure was first employed to improve the recognition sites accessibility, mesoporous silica was applied to reduce mass transfer resistance, and ratiometric fluorescence technique was adopted to achieve visual signal output by doping green CdTe QDs into silica shell. The as-prepared M-R-MIPs exhibited excellent sensitivity when compared to M-R-NIPs and corresponding single fluorescence MIPs sensor. Under the optimized condition, when detection of BHb, the linear range was 0.02-2.0μM with detection limit of 6.3nM, accompanied with distinguished fluorescence color change from yellow to orange to red. The feasibility of the developed method in real samples was successfully evaluated through analysis of BHb in bovine urine and blood samples with satisfactory recoveries of 92.6-101.2%. The developed method proposed in this work proved to be more sensitive and reliable, provided an alternative solution for recognition and determination of protein from real samples.
在本工作中，基于核壳结构开发了用于高灵敏且选择性测定牛血红蛋白（BHb）的介孔结构分子印迹比率荧光传感器（M-R-MIPs）。首先，通过反相微乳液法将红色碲化镉量子点（CdTe QDs）嵌入二氧化硅纳米颗粒中，然后在核二氧化硅上包覆BHb印迹的二氧化硅壳层。为了提高所制备的MIPs传感器的灵敏度，在印迹二氧化硅壳层形成过程中，首先采用功能单体-模板-量子点夹心结构来提高识别位点的可及性，应用介孔二氧化硅来降低传质阻力，并采用比率荧光技术通过将绿色CdTe QDs掺杂到二氧化硅壳层中来实现可视化信号输出。与M-R-NIPs和相应的单荧光MIPs传感器相比，所制备的M-R-MIPs表现出优异的灵敏度。在优化条件下，检测BHb时，线性范围为0.02 - 2.0μM，检测限为6.3nM，伴随着从黄色到橙色再到红色的明显荧光颜色变化。通过分析牛尿液和血液样本中的BHb，成功评估了所开发方法在实际样品中的可行性，回收率令人满意，为92.6 - 101.2%。本工作中提出的所开发方法被证明更灵敏且可靠，为从实际样品中识别和测定蛋白质提供了一种替代解决方案。
