Flexible direct-growth CNT biosensors.
A biosensor was fabricated by growing carbon nanotubes (CNTs) directly on a polyimide flexible substrate at low temperatures (≤400 °C). A biocompatible polymer (poly(para-xylylene), parylene) was subsequently coated on the surface without CNTs as an insulator for future applications of flexible biosensors in in vivo sensing. The feasibility of the CNT flexible biosensor was demonstrated by quantitatively detecting human serum albumin (HSA). The CNT surface was modified with functional groups using UV-ozone, 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDC), and treated with N-hydroxysuccinimide (NHS) to improve the biocompatibility for the conjugation of protein. In addition, anti-HSA (AHSA) was used to capture HSA specifically, and bovine serum albumin (BSA) was applied to block the non-specific sites. The electrical properties of the biosensors applied with various HSA concentrations were measured and quantified using an electrochemical impedance spectroscopy system under AC conditions. The detection limit of the biosensor for HSA detection was approximately 3×10(-11) mg/ml. The proposed sensor has considerable potential for future application in wearable biosensors and implant detection.
National Tsing Hua University, Department of Materials Science and Engineering, 101, Section 2, Kuang-Fu Road, Hsinchu 30013, Taiwan.
Yun-Tzu
YT
Chang
Jing-Huei
JH
Huang
Meng-Che
MC
Tu
Pin
P
Chang
Tri-Rung
TR
Yew
D015374:Biosensing Techniques / Q000295:instrumentation*; D003217:Conductometry / Q000295:instrumentation*; D003460:Crystallization / Q000379:methods*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D006801:Humans; D007118:Immunoassay / Q000295:instrumentation*; D008422:Materials Testing; D036103:Nanotechnology / Q000295:instrumentation; D037742:Nanotubes, Carbon / Q000737:chemistry* / Q000648:ultrastructure*; D010316:Particle Size; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012709:Serum Albumin / Q000032:analysis*
D037742:Nanotubes, Carbon; D012709:Serum Albumin