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The reinforcement of polymer matrices with nanocarbon fillers is highly attractive for electrochemical biosensing (due to enhanced electrical conductivity). Further processing by electrospinning results in versatile nanofibrous mats. This study compares the biosensing performance of composite polyacrylonitrile nanofibers (PAN NFs) electrospun with different carbonaceous fillers (fullerene, carbon nanotubes, graphene). Morphological characterization of the composite NFs is performed by scanning electron microscopy (SEM) and correlated with the performance of the biosensing matrices. Glucose oxidase (GOD) is employed as model enzyme by immobilization through cross-linking. Optimum nanofiller content was evaluated at 2.0 wt%. for carboxyl functionalized-multiwall carbon nanotubes- NFs (highest sensitivity of 61.5 mAM-1cm-2 and limit of detection (LOD) of 2.0 µM), whilst reduced graphene oxide- NFs exhibited 49.3 mAM-1cm-2 sensitivity with the lowest LOD of 1.6 µM within the most extended linear range (up to 20 ˟ 10-3 M). Insignificant effect of interferent sugars led to real sample recovery close to 100%.

Pyreneclicked SNS was subjected to electrochemical homo‐ and copolymerization. Copolymers exhibit multichromic behavior with low band gaps and switching times. Fine tuning of the colors was achieved through control of the copolymerization potential.

In this study two new, fluorophore anchored 2,5-dithienylpyrrole derivatives (SNS-Carb, SNS-Flo) were successfully synthesized via click chemistry. Both monomers were subjected to electrochemical polymerization and the corresponding polymers (PSNS-Carb and PSNS-Flo) were thoroughly characterized for their electrochromic properties. PSNS-Carb displayed yellow to blue coloration in 1.31 s with a coloration efficiency of 120 cm 2 C −1 whereas PSNS-Flo revealed longer switching time (2.67 s) and lower coloration efficiency (78 cm 2 C −1 ). Coexistence of 3,4-ethylenedioxythiophene (EDOT) with SNS-Carb or SNS-Flo in polymerization media resulted in the formation of novel copolymer films (P1 and P2, respectively) having entirely diverged multichromic, superior optoelectronic properties. P1 revealed a switching time of 1.33 s, with a coloration efficiency of 164 cm 2 C −1 , whereas P2 exhibited a slower response time (1.87 s) with a lower coloration efficiency (155 cm 2 C −1 ), as in the case of their respective homopolymers. In general, P1 was shown to reveal higher E values which indicate it's more noticeable and vivid color changing nature compared to P2. When the optoelectronic properties of homopolymers were compared with that of their respective copolymers, there was an explicit enhancement of the color pallet, switching time, optical contrast and coloration efficiency.

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In this study, novel ferrocene-functionalized N-alkyl substituted pyrrole derivatives, namely 4-ferrocenyl-1-[3-(pyrrol-1-yl)propyl]-1H-1,2,3-triazole (Py3Fc), 4-ferrocenyl-1-[4-(pyrrol-1-yl)butyl]-1H-1,2,3-triazole (Py4Fc), and 4-ferrocenyl-1-[6-(pyrrol-1-yl)hexyl]-1H-1,2,3-triazole (Py6Fc), were synthesized via click reaction and the monomers were characterized by 1 H NMR, 13 C NMR, FTIR, and HRMS techniques. Redox properties of the monomers were investigated by cyclic voltammetry (CV) studies. Contrary to general literature, both Py4Fc and Py6Fc were electrochemically polymerized without loss in redox activity of ferrocene group. Moreover, click chemistry was utilized in postpolymerization functionalization. For this purpose, three azide-containing polypyrroles, P(Py3N 3 ), P(Py4N 3 ), and P(Py6N 3 ) were electrochemically synthesized and subjected to click reaction in the presence of ethynylferrocene. CV studies of the post-polymerization functionalized polymers revealed quasi-reversible waves, while only P(Py6-post-Fc) showed the characteristic redox behavior of both polypyrrole and ferrocene. Thus, in this study preparation of a conducting homopolymers of pyrrole having covalently bonded ferrocene units was demonstrated and effect of spacer group is investigated.