NJC
New Journal of Chemistry
A journal for new directions in chemistry
rsc.li/njc
ISSN 1144-0546
PAPER
Metin Ak, M. Kasım Şener et al.
Efficient synthesis of EDOT modified ABBB-type unsymmetrical zinc phthalocyanine: optoelectrochromic and glucose sensing properties of its copolymerized film
14080 | New J. Chem., 2017, 41, 14080--14087 This journal is © The Royal Society of Chemistry and the Centre National de la Recherche Scientifique 2017
Cite this: New J. Chem., 2017, 41, 14080
Efficient synthesis of EDOT modified ABBB-type
unsymmetrical zinc phthalocyanine:
optoelectrochromic and glucose sensing
properties of its copolymerized film
O¨ zge Go¨ktug˘,aTugba Soganci,bMetin Ak *band M. Kasım S- ener *a
A new unsymmetrical zinc(II) phthalocyanine (ZnPc2) bearing one EDOT group was efficiently
synthesized as a monomer through the statistical condensation reaction. The other products of mixed cyclotetramerization ZnPc1, ZnPc3 and ZnPc4 were also isolated. Obtained ZnPc2 is a good precursor for the synthesis of new functional linear electropolymers. This was approved by the successful electrochemical copolymerization reaction between ZnPc2 and SNS type monomer HKCN in which the amino group was desired for the enzyme immobilization. The electrochromic and glucose sensing properties of copolymer P(ZnPc2-co-HKCN) obtained by electrochemical oxidative polymerization were investigated. Based on spectroelectrochemical studies, the P(ZnPc2-co-HKCN) copolymer showed a greenish yellow colour in the reduced state and a dark blue colour in the oxidized state as a film. An optical contrast ratio of 44% at 471 nm was achieved with a fast switching time (2.5 s). Meanwhile, the novel biosensor constructed from P(ZnPc2-co-HKCN) showed a linear amperometric response to glucose within a concentration range of 0.1 mM to 1.5 mM (LOD: 0.049 mM). These data illustrate the possible use of the P(ZnPc2-co-HKCN) modified electrode as an amperometric glucose sensor.
1 Introduction
Electrochromism is a term used for bidirectional processes where the color of the material changes when an electric field is applied.1There are a vast number of chemical species that show electrochromic properties, including metal coordination complexes (e.g. metallophthalocyanines) both in solution and as polymer films, metal oxide films, viologens (in solution and as polymer films) and conducting polymers, as thin films.1,2 Electrochromic compounds are used in display panels and smart materials.3Electrochromic materials which are produced using conductive polymers can be obtained via chemical, electro-chemical or simple coating techniques. In conductive polymers, the colour varies depending on the percentage of doping, the selected monomer, and the applied potential. Thus, it is possible to obtain much more colours and higher contrast by using conductive polymers.4,5 Among the conductive polymers,
poly(3,4-ethylenedioxythiophene) (PEDOT), which is used in the construction of electrochromic materials and works
between transparent and blue, holds a very important place in the literature.6 Besides its conductivity properties, another
important property of PEDOT is its high chemical stability. PEDOT and its derivatives are usually prepared from 3,4-(ethylene-dioxy)thiophene (EDOT)-based monomers using standard oxida-tive chemical or electrochemical polymerization methods.7 The addition of new properties to PEDOT by the substitution of EDOT through the ethylenedioxy group results in new materials with the necessary functions for various application areas and for use as electrochromic materials. Among these applications, the use as a biosensor material has an important place.8PEDOT can be easily obtained by electrochemical polymerization and used for the immobilization of bioreceptors such as glucose oxidase enzyme (GOx). In this case, PEDOT derivatives constitute the chemically inert matrix for the immobilization of GOx, and their role is to provide the necessary electrical conductivity to transduce the occurrence of the coupling event into the analytical signal.9
Glucose is converted to gluconic acid and hydrogen peroxide in the presence of oxygen by the effect of GOx which is immobilized on the polymeric film on the surface of the electrode modified via the electropolymerization technique. The determination of the glucose concentration using many conductive polymer biosensors is performed by monitoring the reduction current of the oxygen consumed during the enzymatic reaction or the oxidation current
aDepartment of Chemistry, Yıldız Technical University, 34210, Davutpas-a, I˙stanbul,
Turkey. E-mail: mkasimsener@gmail.com
bDepartment of Chemistry, Pamukkale University, 20017, Kınıklı, Denizli, Turkey.
E-mail: metinak@pau.edu.tr Received 29th August 2017, Accepted 7th October 2017 DOI: 10.1039/c7nj03250a rsc.li/njc
