Characteristics of Polysilicon Wire Glucose Sensors with a Surface Modified by Silica Nanoparticles/γ-APTES Nanocomposite

Sensors

Jing-Jenn Lin²  Po-Yen Hsu¹  You-Lin Wu¹ 

[1] Department of Electrical Engineering, National Chi Nan University, Puli, Nantou 54561, Taiwan; E-Mails:;Department of Applied Materials and Optoelectronic Engineering, National Chi Nan University, Puli, Nantou 54561, Taiwan

关键词: line width dependence;    polysilicon wire;    γ-APTES;    PDMS;    silica nanoparticles;   

DOI  :  10.3390/s110302796

来源: mdpi

【 摘 要 】

This report investigates the sensing characteristics of polysilicon wire (PSW) glucose biosensors, including thickness characteristics and line-width effects on detection limits, linear range and interference immunity with membranes coated by micropipette/spin-coating and focus-ion-beam (FIB) processed capillary atomic-force-microscopy (C-AFM) tip scan/coating methods. The PSW surface was modified with a mixture of 3-aminopropyl-triethoxysilane (γ-APTES) and polydimethylsiloxane (PDMS)-treated hydrophobic fumed silica nanoparticles (NPs). We found that the thickness of the γ-APTES+NPs nonocomposite could be controlled well at about 22 nm with small relative standard deviation (RSD) with repeated C-AFM tip scan/coatings. The detection limit increased and linear range decreased with the line width of the PSW through the tip-coating process. Interestingly, the interference immunity ability improves as the line width increases. For a 500 nm-wide PSW, the percentage changes of the channel current density changes (ΔJ) caused by acetaminophen (AP) can be kept below 3.5% at an ultra-high AP-to-glucose concentration ratio of 600:1. Simulation results showed that the line width dependence of interference immunity was strongly correlated with the channel electrical field of the PSW biosensor.

【 授权许可】

CC BY   
© 2011 by the authors; licensee MDPI, Basel, Switzerland.