title: Preparation of highly conjugated water-dispersible graphene-butyric acid for the enhancement of electron transfer within polyamic acid-benzoxazole: potential applications in electrochemical sensing.
abstract: To break through the long time and complex procedures for the preparation of highly conjugated reduced graphene oxide (r-GO) in developing electrochemical sensor, a time-saving and simple method is investigated in this study. One novel step of the exfoliated accompanying carboxylated graphene sheet from pristine is achieved via Friedel-Crafts acylation. By electrophilic aromatic substitution, the succinic anhydride ring is opened and attaches covalently to the graphene sheet (Gs) to form exfoliated graphene with grafted 1-one-butyric acid (Gs-BA). The grafting chain converts anions in aqueous solution to maintain Gs-BA in a stable dispersion and noticeably decreases the π-π stacking of the exfoliated Gs during the drying process. The analytical results of the absorption spectroscopy demonstrate that the conjugation of Gs-BA is not significantly destroyed by this chemical modification; Gs-BA retains the Gs electrical properties favorable for developing electrochemical sensors. When polyamic acid-benzoxazole (PAA-BO), a hydrogen peroxide (H₂O₂)-sensitive probe, hybridizes with Gs-BA to form Gs-BA-PAA-BO, the electron transfer rate relating to the response time improves markedly from 1.09 s(-1) to 38.8 s(-1). Additionally, it offers a high performance for H₂O₂ sensing in terms of sensitivity and response time, making this method applicable for developing glucose and choline biosensors.
authors.affiliation: Department of Chemical and Materials Engineering, Chang Gung University, Taoyuan, 33302 Taiwan, ROC.
authors.forename: Hsiao-Chien
authors.initials: HC
authors.lastname: Chen
authors.forename: Yen-Hsuan
authors.initials: YH
authors.lastname: Chen
authors.forename: Shi-Liang
authors.initials: SL
authors.lastname: Chen
authors.forename: Yaw-Terng
authors.initials: YT
authors.lastname: Chern
authors.forename: Rung-Ywan
authors.initials: RY
authors.lastname: Tsai
authors.forename: Mu-Yi
authors.initials: MY
authors.lastname: Hua
mesh_terms: D001555:Benzene Derivatives / Q000737:chemistry*; D001583:Benzoxazoles / Q000737:chemistry*; D015374:Biosensing Techniques / Q000379:methods; D020148:Butyric Acid / Q000737:chemistry*; D002384:Catalysis; D002794:Choline / Q000032:analysis; D055664:Electrochemical Techniques / Q000379:methods*; D004566:Electrodes; D004579:Electron Transport; D004583:Electrons; D005947:Glucose / Q000032:analysis; D006046:Gold / Q000737:chemistry; D006108:Graphite / Q000737:chemistry*; D006861:Hydrogen Peroxide / Q000032:analysis*; D011108:Polymers / Q000737:chemistry*; D012680:Sensitivity and Specificity
chemical_list: D001555:Benzene Derivatives; D001583:Benzoxazoles; D011108:Polymers; C513053:polyamic acid; D020148:Butyric Acid; D006046:Gold; D006108:Graphite; D006861:Hydrogen Peroxide; D005947:Glucose; D002794:Choline