295 Copyright © All rights are reserved by Moslem Mansour Lakouraj. Modern Approaches on Material Science Research Article Fabrication of a Nanocomposite Based on Pectin/ Polyaniline/Graphene Oxide as Novel Electrically Conductive Biomaterial for Biosensing Detection of Hemoglobin Moslem Mansour Lakouraj 1 *, Azita Alipour 1 , Mohsen NajafiRoudbari 2 and Reza Ojani 2 1 Department of Organic Chemistry, Faculty of Chemistry, University of Mazandaran, Iran 2 Department of Analytical Chemistry, Faculty of Chemistry, University of Mazandaran, Iran *Corresponding author: Moslem Mansour Lakouraj, Polymer Laboratory, Department of Organic Chemistry, Faculty of Chemistry, University of Mazandaran, P.O. Box 47416, Babolsar, Iran Received: March 06, 2020 Published: April 08, 2020 Introduction Over the recent years, there have been many investigations on carbon nanomaterials namely graphene oxide due to their high surface area, electrical and electrochemical properties. GO is a single sheet of graphite oxide that because of a wide range of functional groups including oxygen on its surface capable to be modified chemically with other materials [1-2].GO is recognized as an actual nanocarbon due to its superior mechanical, structural and thermal properties relative to other conventional nanomaterials. It can be synthesized via Hummer method [1,3]. PA/GO nanocomposites with improved electrochemical performance as energy storage and supercapacitor were reported in some studies [4-6]. However,there are few studies on PA/GO nanocomposites as electrocatalyst in biosensors [7-8]. The poor electrical conductivity of GO caused by the functional groups creating high electron transfer resistant, like carboxyl, hydroxyl and epoxy groups in its surface limited its direct application in electrochemical applications. However, the incorporation of graphene oxide in a conducting polymer matrix results in good mechanical strength and electrochemical properties [9]. PA is one of the conducting polymers which have attracted much attention in sensor areas as excellent organic conductor with superior electrical and electrochemical properties, good chemical and environmental stability and biocompatibility [10]. The combination of PA with other nanomaterials can provide its application as a desirable matrix for immobilization and detection of biomolecules via charge transfer reactions [11-14]. Pectin is a biocompatible high-molecular weight polysaccharide extracted from cell walls of plants that is composed of three structures of homogalacturonan, rhamnogalacturonan I and rhamnogalacturonan II. In spite of its unique properties such as good gelling properties, biocompatibility, non-toxicity and biodegradability, it has some inherent flaws that make it unfavorable for application in some specific fields. The chemical modification of pectin was considered to remove these drawbacks. Due to the existence of structural groups such as hydroxyl and carboxyl group on its surface along the backbone, a wide range of pectin derivatives can be prepared via chemical modification [15]. In addition, pectin due to possessing ISSN: 2641-6921 DOI: 10.32474/MAMS.2020.02.000148 Abstract A novel biomaterial based on hydrolyzed pectin(HP)/polyaniline(PA)/graphene oxide(GO) has been prepared via chemical polymerization method. The SEM analyses revealed a rod-like and laminated morphology for NH-mGO@HP and NH-mGO@HP- PA nanocomposites. Higher thermal stability for NH-mGO@HP-PA was obtained than other samples. Biosensor was designed via electrodeposition of NH-mGO@HP-PA nanocomposite on carbon graphite electrode. Biosensor activity showed a considerable increase in oxidation current by the nanocomposite. The NH-mGO@HP-PA indicated higher electrical conductivity compared to pure PA. Keywords: Polyaniline; Graphene oxide; Electrochemical properties; Hemoglobin biosensor