Fluorescent biosensing systems

Fluorescent Biosensing Systems Based on Analyte-Induced Conformational Changes of Genetically Engineered Periplasmic Binding Proteins... 

Dimethylamino)ethanethiol DMAET-capped CdTe NPs were employed in the construction of aptamer-based biosensing system for proteins [109]. Highly efficient and sensitive determination of alkaloids and amino acids using CE in conjunction with sequential light-emitting diode-induced fluorescence (LEDIF) and ECL method was carried out. In the CE-LEDIF-ECL system, the ECL detector was located in the outlet of the capillary, while the LEDIF detector was positioned 12 cm from the outlet [110]. Ru(bpy)3 in MWCNTs/Nafion composite membrane was immobilized for an ECL method for reduced nicotinamide adenine dinucleotide (NADH) with a detection limit of 8.2 x 10 M [111]. 

Reprinted with permission from Analytical Chemistry, 80, Ho, J. A. et al., Using liposomal fluorescent biolabels to develop an immunoaffi-nity chromatographic biosensing system for biotin, 6405-6409. Copyright (2008) American Chemical Society.)... 

Implementing nanoparticles in biosensing applications relies heavily on the nano-paiticle s core composition, surface functionalization, sensing mechanism, and modality. The aforementioned aspects in the design of nanoparticle-based sensors provide the main challenge to the development of novel nanoparticle-based systems to replace fluorescent molecular indicators such as DCFH for sensing ROS... 

To explore the utility of DNA-mediated electron-transfer events for biosensing applications, an electrochemical assay was developed [23-25]. Electrochemical sensors are typically more portable and inexpensive than those using fluorescence-based detection, hence a system suitable for monitoring electron transfer through DNA duplexes immobilized on the surface of an electrode was sought. 

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