Novel SWCNT-hybrid nanomaterial functionalized with subphthalocyanine substituted asymmetrical zinc (II) phthalocyanine conjugate: Design, synthesis, characterization and sensor properties for pesticides

Abstract

The novel asymmetric zinc (II) phthalocyanines containing one ethyloxy azido and three iodine (Iodo-Pc) or subphthalocyanine (SubPc-Pc) groups were designed and synthesized for the first time. These novel phthalocyanines were chemically characterized by common spectral methods such as FT-IR, UV-vis, H-1-NMR,C- 13-NMR and MALDI-TOF mass spectroscopy and elemental analyses as well. Furthermore, a novel hybrid carbon nanomaterial (SWCNT-SubPc-Pc) bearing subphthalocyanine substituted zinc (II) phthalocyanine conjugate on the single walled carbon nanotube (SWCNT) surface was also prepared via azide-alkyne Huisgen cycloaddition (click) reaction. This novel hybrid carbon nanomaterial was chemically characterized by UV-vis, FT-IR and Raman spectroscopies. The thermal behaviour of the prepared SWCNT-SubPc-Pc was characterized by thermogravimetric analysis. Surface morphologies of the hybrid material were also investigated by scanning and transmission electron microscopies. SWCNT-SubPc-Pc hybrid nanomaterial was successfully modified on glassy carbon electrode (GCE) by using drop cast method. Then, the GCE/SWCNT-SubPc-Pc electrode was tested as pesticide sensor via electrochemical methods. The electrochemical responses were recorded using differential pulse (DPV) and cyclic voltammetries. The modified electrode acted as selectively to methyl parathion among the used pesticides (methyl parathion, acetamiprid and chlorantraniliprole). The electrochemical sensor behaviour exhibited a broad linear range (2.5 nM and 3.75 x 10(-8) M) and low detection limit (1.78 nM) for methyl parathion. Moreover, high performance liquid chromatography was used to validate the results obtained from orange and cherry juice samples with respect to the DPV results.