Development of a Quartz Crystal Microbalance Biosensor with Aptamers as Bio-recognition Element

Sensors

Chunyan Yao³  Tangyou Zhu¹  Yongzhi Qi²  Yuhui Zhao³  Han Xia³ 

[1] Department of Dermatology, Daping Hospital, Third Military Medical University, Chongqing 400042, China; E-Mail:;Department of Laboratory Medicine, the General Navy Hospital, Beijing 100037, China; E-Mail:;Department of Laboratory Medicine, Southwest Hospital, Third Military Medical University, Chongqing 400038, China; E-Mails

关键词: quartz crystal microbalance;    biosensor;    aptamer;    antibody;    IgE;   

DOI  :  10.3390/s100605859

来源: mdpi

【 摘 要 】

The ultimate goal in any biosensor development project is its use for actual sample detection. Recently, there has been an interest in biosensors with aptamers as bio-recognition elements, but reported examples all deal with standards, not human serum. In order to verify the differences of aptamer-based biosensor and antibody-based biosensor in clinical detection, a comparison of the performance of aptamer-based and antibody-based quartz crystal microbalance (QCM) biosensors for the detection of immunoglobulin E (IgE) in human serum was carried out. Aptamers (or antibodies) specific to IgE were immobilized on the gold surface of a quartz crystal. The frequency shifts of the QCM were measured. The linear range with the antibody (10–240 μg/L) compared to that of the aptamer (2.5–200 μg/L), but a lower detection limit could be observed in the aptamer-based biosensor. The reproducibility of the two biosensors was comparable. The aptamers were equivalent or superior to antibodies in terms of specificity and sensitivity. In addition, the aptamer receptors could tolerate repeated affine layer regeneration after ligand binding and recycling of the biosensor with little loss of sensitivity. When stored for three weeks, the frequency shifts of the aptamer-coated crystals were all greater than 90% of those on the response at the first day.

【 授权许可】

CC BY   
© 2010 by the authors; licensee MDPI, Basel, Switzerland.