Aptamer-based Piezoelectric Quartz Crystal Biosensor / 中华医院感染学杂志

ABSTRACT

OBJECTIVE To establish an aptamer-based piezoelectric sensor assay to detect human immunoglobulin E (IgE) and acquire the parameters about this kind of biosensor. METHODS Anti-IgE aptamers were immobilized on the gold surface of piezoelectric quartz crystal sensor with biotin-avidin method. The reaction between anti-IgE aptamers and IgE was monitored in time on piezoelectric sensor. Different concentrations of IgE were detected and the calibration curve of IgE was drawn. Non-specific response signals of BSA, IgG and IgE were monitored to show the detecting specificity of aptamer-based sensor. RESULTS For the aptamer-based sensor, the lowest limit of detection was 0.055mg/L and the linear range was 0.1-2.5mg/L. Non-specific signals of this sensor were less than 5% of specific signals of IgE at the same concentration. CONCLUSIONS The aptamer-based piezoelectric sensor can detect 5.5 ng IgE while the non-specific signals are very low. So this aptamer-based sensor is hopeful to be applied to clinical laboratory diagnosis.