Bioaffinity assays

Wiklund M, Hertz HM (2006) Ultrasonic enhancement of bead-based bioaffinity assays. Lab Chip 6 1279-1292... 

Specific bioaffinity assays are always accompanied with nonspecific binding interactions and this has been seen as an obstacle in assay development. However, nonspecific binding in combination with core—shell europium(III) and europium (in)-dyed polymeric nanoparticles has been recently exploited in FRET-based assays for total protein concentration measiuement [137, 138], The method was based on the competitive adsorption of sample proteins and acceptor-labeled proteins to polymeric Eu(Ill) nanoparticles. High sensitivity and low, subnanomolar limit of detection was partially reached due to a short Forster s radius as the acceptor label was brought in direct contact with the surface. 

The HECL intensity of lanthanide chelates is sufficiently strong for them to be used as labels in bioaffinity assays, especially when time-resolved detection is utilized. The organic luminophores showing their singlet state emission suffer from the fact... 

Other Bioaffinity Assays. For experiments investigating the effect of streptavidin concentration on the above biosensing stem, the protocol of section 2.4.2 was followed except that a streptavidin concentration of 2.5 fig/mh was used and an incubation time of 45 min was necessary to reach saturation. 

Sftniin AHsorptinn F Tgp<>riiin>iits. Nonspecific protein adsorpHon fixmi human serum was tested in a series of experiments on Nb20s-coated waveguides. Bioaffinity assays were carried out in HEPES-2 buffer, as described in sections 2.4.1 and... 

Figure 7. Results from OWLS measurements on the sequential adsorption of avidin, oRIgG-biotin, and RIgG on mixed polymeric interfaces based on mixtures of PLL-g-PEG and PPB20 with various ratios. The inset shows the receptor-to-ligand ratio for each step of the bioaffinity assay.

Kokko, T Kokko, L. Soukka, T. Loevgren, T. Homogeneous non-competitive bioaffinity assay based on fluorescence resonance energy transfer. Anal. Chim. Acta 2007, 585, 120-125. 

Potentiometric biosensors based in both ISE and ISFET for water analysis have been widely developed in the last few years, with recent research leading to nanomaterial-based devices. New nanoparticle (NP)-based signal amplification and coding strategies for bioaffinity assays are in use, along with molecular carbon-nanotube (CNT) wires for achieving efficient electrical communication with redox-enzyme and nanowire-based label-free DNA sensors. ... 

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