Improvement of protein stability in protein microarrays

Protein stability in microarrays was improved using protein stabilizers. PEG 200 at 30% (w/v) was the most efficient stabilizer giving over 4-fold improvement in protein stability compared to without the stabilizer. PEG 200 above 10% (w/v) in the array solution prevented the evaporation of water in the sample and thereby improved protein stability in the microarray. When the streptavidin-biotin binding reaction was performed under optimized conditions, biotin-BSA-fluorescein isothiocyanate (FITC) was detected from 1 ng ml^–1 to 5 g ml^–1 by fluorescence analysis.