Regeneration Ability of Aptamer-coated Piezoelectric Quartz Crystal Chips / 中华医院感染学杂志

ABSTRACT

OBJECTIVE To study the optimal reagent for regeneration of aptamer-coated piezoelectric quartz crystal chips and detect storage ability of aptamer-coated chips. METHODS Anti-IgE aptamers were immobilized on the gold surface of piezoelectric quartz crystal biosensor with biotin-avidin method. The reaction between anti-IgE aptamers and IgE was monitored in time on piezoelectric sensor. We tried to regenerate the sensor surface after binding IgE by rinsing the aptamer-coated chips with HCl, NaOH, EDTA, urea and formamide individually. Aptamer-coated chips were stored in PBS with 0.1% sodium azide and the stored chips were used to detect IgE in 35 days. RESULTS Of the five reagents, EDTA was the best one for regeneration of aptamer-coated chips and the sensor could retain 91.5% of the original detecting signals after five regeneration cycles. Moreover, the aptamer-coated chips could be stored in the binding buffer for 21 days without obvious loss of activity. CONCLUSIONS Compared with antibody-based piezoelectric sensor, aptamer-based sensor has lower cost, more regeneration cycles and longer time for the storage of chips. This series of experiments shows the superiority of aptamer detection.