Comparison of surface and hydrogel-based protein microchips

Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, Vavilov str., 32, 119991 Moscow, Russia.
Analytical Biochemistry (Impact Factor: 2.22). 10/2007; 368(2):205-13. DOI: 10.1016/j.ab.2007.04.040
Source: PubMed


Protein microchips are designed for high-throughput evaluation of the concentrations and activities of various proteins. The rapid advance in microchip technology and a wide variety of existing techniques pose the problem of unified approach to the assessment and comparison of different platforms. Here we compare the characteristics of protein microchips developed for quantitative immunoassay with those of antibodies immobilized on glass surfaces and in hemispherical gel pads. Spotting concentrations of antibodies used for manufacturing of microchips of both types and concentrations of antigen in analyte solution were identical. We compared the efficiency of antibody immobilization, the intensity of fluorescence signals for both direct and sandwich-type immunoassays, and the reaction-diffusion kinetics of the formation of antibody-antigen complexes for surface and gel-based microchips. Our results demonstrate higher capacity and sensitivity for the hydrogel-based protein microchips, while fluorescence saturation kinetics for the two types of microarrays was comparable.

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Available from: Vladimir R Chechetkin
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    • " catProductDetail&productID=2-3128-00&catID=601950& backButton=true), polymer monoliths [18] [19], sol-gel polymers [20] [21], the inner surfaces of capillary walls [22] [23], and various types of membranes [24] [25]. But the most promising systems for heterogeneous enzyme digestion are likely those relying on three-dimensional hydrogels as scaffolds for housing immobilized enzymes [26] [27] [28] [29]. "
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    • "The enhancement of fluorescence by metal coating for hydrated hemispherical gel pads is comparable to the enhancement reported previously for surface microchips (Aslan et al., 2005; Lakowicz, 2005; Sabanayagam and Lakowicz, 2007; Sauer et al., 2005; Strohsahl et al., 2007). As was proved earlier (Zubtsov et al., 2007), the higher immobilization capacity of gel pads results in fluorescence signals an order of magnitude higher than the signals from the surface microchips. This advantage of gel-based microchips remains valid for metal-enhanced fluorescence as well. "
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