Extensibility effect of poly(3-hexylthiophene) on the glucose sensing performance of mixed poly(3-hexylthiophene)/octadecylamine/glucose oxidase Langmuir-Blodgett films

• Published in: Colloids and surfaces, B, Biointerfaces Vol. 155; pp. 104 - 110
• Main Authors: Wang, Ke-Hsuan, Hsu, Wen-Ping, Chen, Liang-Huei, Lin, Wei-Don, Lee, Yuh-Lang
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01.07.2017
• Subjects: Adsorption; Aluminum Silicates - chemistry; Amines - chemistry; Biosensing Techniques - methods; Buffers; Electrochemical Techniques; Enzymes, Immobilized - chemistry; Glucose - analysis; Glucose oxidase (GOx); Glucose Oxidase - chemistry; Glucose sensor; Langmuir-Blodgett films; Membranes, Artificial; Poly(3-hexylthiophene); Protein Structure, Secondary; Solutions; Surface Properties; Thiophenes - chemistry; Poly(3-hexylthiophene); Langmuir-Blodgett films; Glucose sensor; Glucose oxidase (GOx)
• ISSN: 0927-7765; 1873-4367
• DOI: 10.1016/j.colsurfb.2017.04.006

[Display omitted] •P3HT molecules tend to aggregate at the air/liquid interface.•The presence of ODA can enhance the extensibility of P3HT at the interface.•The sensing performance of Glucose Oxidase LB films is improved by adding P3HT.•The performance of a sensing film is improved by increasing extensibility of P3HT. Poly(3-hexylthiophene) (P3HT) is utilized as a material to enhance the glucose sensing performance of glucose oxidase (GOx) Langmuir-Blodgett (LB) films. To enhance the extensibility and homogeneity of the P3HT in the LB films, octadecylamine (ODA) is introduced. The characteristics of the mixed P3HT/ODA Langmuir monolayers are investigated first and then, utilized as template layers to adsorb GOx from the subphase, preparing P3HT/ODA/GOx Langmuir-Blodgett films for glucose sensing. The results show that P3HT molecules tend to aggregate at the air/liquid interface and, furthermore, the P3HT monolayer has a weak ability to adsorb GOx from the subphase. By using mixed P3HT/ODA monolayer, the presence of ODA not only inhibits the aggregation of P3HT, but also increases the adsorption ability of the monolayer to GOx. The extensibility of P3HT and the homogeneity of the P3HT/ODA monolayers are closely related to the concentration of P3HT/ODA stock solutions. On the glucose sensing experiments, the performance of the P3HT/ODA/GOx LB film is greatly improved due to the presence of P3HT and, furthermore, the sensibility increases with increasing extensibility of P3HT molecules. The best sensitivity achieved for the P3HT/ODA/GOx film is 5.4μAmM−1cm−2 which is over two times the value obtained by the ODA/GOx film (2.3μAmM−1cm−2).