7118 | J. Mater. Chem. B, 2017, 5, 7118--7125 This journal is © The Royal Society of Chemistry 2017
Cite this: J. Mater. Chem. B, 2017, 5, 7118
Rhodamine functionalized conducting polymers
for dual intention: electrochemical sensing and
fluorescence imaging of cells†
Fatma Ozturk Kirbay, aRukiye Ayranci,b Metin Ak, *bDilek Odaci Demirkol *a and Suna Timura
We report here the electrochemical co-polymerization of two functional monomers, one containing fluorescent rhodamine dye (RF) and the other monomer having amine groups (RD), onto electroactive Indium Tin Oxide (ITO) glass. After one step preparation of these surfaces, a three peptide called ArginylGlysylAspartic acid (RGD) was immobilized via EDC chemistry by using amine groups (P(RF-co-RD)/RGD) of the co-polymer, for further use in various bio-applications such as cell adhesion and imaging as well as electrochemical cell sensing. The resultant RGD bound and also fluorescent platforms were utilized as targeted adhesion materials towards integrin avb3 receptor positive (U87-MG) cells and the selectivity was checked by using HaCaT cells as a control. Finally, electrochemical measurements were carried out to characterize step by step surface modification and detection of cell attachment. As a result, P(RF-co-RD)/RGD is a promising material for multi-purpose uses, such as fluorescence imaging without the need for an additional dye for cell visualization and as a targeted adhesion and electrochemical cell sensing platform.
Introduction
Electroactive biomaterials such as conductive polymers are ‘‘smart’’ biomaterials that allow the direct delivery of electro-chemical and electromechanical impulses to cells.1–3Conductive
polymers (CPs) are advantageous because of the ease of con-trolling their electrical and optical properties. They show high conductivity/weight ratios and can be made biocompatible and biodegradable.4,5 Additionally, a great potential of conductive polymers is that their chemical, electrical and physical proper-ties can be tailored to the specific needs of their application by incorporating antibodies, enzymes and other biological molecules.6
CPs have become very significant in recent years due to their superior electrochemical and optical properties. These superior properties lead to many applications in different scientific and technological areas such as organic light emitting technological areas such as organic light emitting diodes (OLEDs), solar cells, electrochromic devices, and biosensors.7–11CPs are also promis-ing materials for the preparation of bio-functional surfaces on
supports for cell and tissue engineering, and electrochemical and optical biosensors.12,13Addition of groups such as amine, carboxyl and thiol, etc. to CPs provides the functionality for biomolecule immobilization on modified surfaces to design sensing systems with high operational stability.14 Recently,
4-amino-N-(2,5-di(thiophen-2-yl)-1H-pyrrol-1-yl) benzamide was synthesized and used for the covalent attachment of either enzyme (pyranose oxidase) or bacteria (Gluconobacter oxydans) on the electroactive surfaces to construct first generation enzymatic and microbial biosensors.15Moreover, in the other studies, ferrocene (Fc) was utilized for the functionalization of the CPs and a copolymer of amine- and Fc-functionalized CPs was formed on the electrodes during one step electropolymer-ization. Then, enzyme immobilization was carried out with covalent coupling on Fc–CP covered surfaces for the fabrication of second generation enzyme biosensors.16–18In another study, an EDOT-substituted bis(2-pyridylimino)isoindolato-palladium complex for catalyzing bioelectrocatalytic reaction and an amine functionalized thienylpyrrole for covalent immobiliza-tion of GOx have been synthesized. The biosensor platform has been prepared by copolymerization of these two electroactive monomers and it showed superior performance compared to a similar one in the literature.16
On the other hand, cell-on a chip systems have attracted great attention due to their high sensitivity, possible adaption to flow injection configuration as well as real-time analysis.17,18 Also, these systems provide monitoring of cell viability, cell
aEge University, Faculty of Science, Biochemistry Department, 35100 Bornova,
Izmir, Turkey. E-mail: dilek.odaci.demirkol@ege.edu.tr
bPamukkale University, Faculty of Art and Science, Chemistry Department,
20017 Denizli, Turkey. E-mail: metinak@pau.edu.tr
†Electronic supplementary information (ESI) available. See DOI: 10.1039/ c7tb01716b Received 22nd June 2017, Accepted 1st August 2017 DOI: 10.1039/c7tb01716b rsc.li/materials-b
Journal of
Materials Chemistry B
PAPER
Published on 01 August 2017. Downloaded by Pamukkale University on 07/09/2017 10:48:07.
View Article Online View Journal | View Issue
