Applications Of Cellulose-Based Fibres, Functionalised With Zinc Phthalocyanine, As Photosensitisers For Gas Sensing, Degradation And Bacteria Inactivation

Abstract

Zinc phthalocyanine complex was synthesised and incorporated into natural cellulose-based fibres extracted, from oil palm mesocarp fibres and pineapple leaves wastes, with the view of producing ZnPc-functionalised fibres, to compensate for its’ aggregation challenge in most solutions and for easy recovery from reaction solutions, easy disposal after use and for repeated use. The ZnPc-functionalised fibres were characterised by different spectroscopic, thermal and microscopic methods. The results suggested that, the free zinc phthalocyanine dye was indeed embedded and well dispersed within the cellulose-based fibres. The physico-chemical properties of the functionalised cellulose-based fibres were also assessed and found to exhibit the same fluorescence behaviour, that is characteristic of zinc phthalocyanine in solution. This makes them promising for qualitative detection of gases by fluorescence quenching. The photoactivity and singlet oxygen production effects of zinc phthalocyanine were also preserved within the fibre matrices, making them promising photosensitisers for photo-oxidation and photodynamic applications. When applied for optical detection of nitrogen dioxide gas, photodegradation of crystal violet dye and invitro photodynamic antibacterial susceptibility tests, they showed promise for qualitative detection of nitrogen dioxide gas by fluorescence quenching, for the conversion of an organic pollutant, crystal violet in aqueous solutions and as a topical antibacterial agent against methicillin/multidrug-resistant strains, Staphylococcus aureus (MRSA) and Pseudomonas aeruginosa under day/sunlight and redlight radiations.