An aptamer-based quartz crystal microbalance biosensor for sensitive and selective detection of leukemia cells using silver-enhanced gold nanoparticle label

An aptamer-based quartz crystal microbalance (QCM) biosensor was developed for the selective and sensitive detection of leukemia cells. In this strategy, aminophenylboronic acid-modified gold nanoparticles (APBA-AuNPs) which could bind to cell membrane were used for the labeling of cells followed by silver enhancement, through which significant signal amplification was achieved. Both the QCM and fluorescence microscopy results manifested the selectivity of the sensor designed. A good linear relationship between the frequency response and cell concentration over the range of 2×103–1×105 cells/mL was obtained, with a detection limit of 1160 cells/mL. This approach provides a simple, rapid, and economical method for leukemia cell analysis which might have great potential for further use.