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(Reference retrieved automatically from Web of Science through information on FAPESP grant and its corresponding number as mentioned in the publication by the authors.)

The layer-by-layer assembly of reduced graphene oxide films and their application as solution-gated field-effect transistors

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Author(s):
dos Santos, Fabricio A. [1] ; Vieira, Nirton C. S. [2] ; Zambianco, Naiara A. [1] ; Janegitz, Bruno C. [3] ; Zucolotto, Valtencir [1]
Total Authors: 5
Affiliation:
[1] Univ Sao Paulo, Phys Inst Sao Carlos, Nanomed & Nanotoxicol Grp, CP 369, BR-13560970 Sao Carlos, SP - Brazil
[2] Univ Fed Sao Paulo, Inst Sci & Technol, BR-12231280 Sao Jose Dos Campos, SP - Brazil
[3] Univ Fed Sao Carlos, Dept Nat Sci Math & Educ, BR-13600970 Araras, SP - Brazil
Total Affiliations: 3
Document type: Journal article
Source: Applied Surface Science; v. 543, MAR 30 2021.
Web of Science Citations: 0
Abstract

In this study, graphene oxide (GO) has been reduced in two different ways for the production of oppositely charged reduced graphene oxide (rGO) sheets. One reduction route consisted of the covalent modification of GO with (3-aminopropyl) triethoxysilane and subsequent chemical reduction to produce positively charged rGO. In the second route employed, GO was reduced in a domestic microwave oven, in which the presence of urea doped the material with nitrogen, increasing its electrical conductivity considerably. Multilayers of oppositely charged rGO were manufactured using the layer-by-layer (LbL) assembly technique. The kinetics and growth of multi layers were monitored by UV-Vis absorption spectroscopy and quartz crystal microbalance. rGO multilayers on the interdigitated gold electrodes originate high conductive films, in which the number of deposited layers controls the conductivity. As a solution-gated field-effect transistor, the devices presented high trans conductance; (90 mu S and 55 mu S for holes and electrons, respectively). Upon modification of the LbL films with papain, used as a biological recognition element, the devices were capable of detecting Cystatin C protein (a chronic renal disease biomarker) in synthetic urine in concentrations as low as 5 ng.mL(-1). Therefore, the proposed transistors proposed here represent interesting alternatives as novel sensors and biosensors platforms. (AU)

FAPESP's process: 17/21898-6 - New conductive devices for application in electrochemical sensing and biosensing
Grantee:Bruno Campos Janegitz
Support Opportunities: Regular Research Grants
FAPESP's process: 18/07508-3 - Exploring the electrical and optical properties of graphene derivatives for the detection of cyanotoxins
Grantee:Nirton Cristi Silva Vieira
Support Opportunities: Regular Research Grants
FAPESP's process: 17/21097-3 - Bee-agriculture interactions: perspectives to sustainable use
Grantee:Osmar Malaspina
Support Opportunities: BIOTA-FAPESP Program - Thematic Grants