Integration of a Miniature Quartz Crystal Microbalance with a Microfluidic Chip for Amyloid Beta-Aβ42 Quantitation

Sensors

Wenyan Tao²  Qingji Xie¹  Hairui Wang²  Shanming Ke²  Peng Lin²  Xierong Zeng² 

[1] College of Chemistry and Chemical Engineering, Hunan Normal University, Changsha 410081, China; E-Mail:;Shenzhen Key Laboratory of Special Functional Materials & Shenzhen Engineering Laboratory for Advance Technology of Ceramics, College of Materials Science and Engineering, Shenzhen University, Shenzhen 518060, China; E-Mails:

关键词: integration;    miniature quartz crystal microbalance;    polydimethylsiloxane;    amyloid polypeptide–Aβ₄₂;   

DOI  :  10.3390/s151025746

来源: mdpi

【 摘 要 】

A miniature quartz crystal microbalance (mQCM) was integrated with a polydimethylsiloxane (PDMS) microfluidic device for on-chip determination of amyloid polypeptide–Aβ₄₂. The integration techniques included photolithography and plasma coupling. Aβ₄₂ antibody was immobilized on the mQCM surface using a cross-linker method, and the resonance frequency of mQCM shifted negatively due to antibody-antigen binding. A linear range from 0.1 µM to 3.2 µM was achieved. By using matrix elimination buffer, i.e., matrix phosphate buffer containing 500 µg/mL dextran and 0.5% Tween 20, Aβ₄₂ could be successfully detected in the presence of 75% human serum. Additionally, high temperature treatments at 150 °C provided a valid method to recover mQCM, and PDMS-mQCM microfluidic device could be reused to some extent. Since the detectable Aβ₄₂ concentration could be as low as 0.1 µM, which is close to cut-off value for Alzheimer patients, the PDMS-mQCM device could be applied in early Alzheimer’s disease diagnosis.

【 授权许可】

CC BY   
© 2015 by the authors; licensee MDPI, Basel, Switzerland.