Philippine E-Journals

Chlorophyll and Chlorophyll Doped Elastomer as Instructional Materials in Teaching Fluorescence

Maria Flora P. Janer Renovalles | Raphael A. Guerrero

Discipline: Science

 

Abstract:

Chlorophyll extract and chlorophyll doped elastomer are presented as instructional materials in teaching fluorescence. A fluorescing organic compound, chlorophyll can be extracted from almost any plant making it readily available and virtually free. It poses no medical and environmental hazards. Optical/fluorescence properties of chlorophyll in acetone solution and chlorophyll immobilized by elastomers were determined in this study. The feasibility of the chlorophyll doped elastomer as a classroom demonstration material using UV cold cathode fluorescent lamp as excitation source is established. Chlorophyll was extracted from Paspalum conjugatum using acetone as solvent. Chlorophyll doped samples were prepared by using Sylgard 184 or polydimethylsiloxane (PDMS) as an elastomer matrix for chlorophyll. Optical characterization of chlorophyll-acetone solution and chlorophyll immobilized by silicone was performed. The fluorescence spectrum of chlorophyll solution is remarkably different from that of chlorophyll immobilized within the elastomeric host. Chlorophyll solution exhibits concentration quenching and a red spectral shift as concentration increases. Chlorophyll in acetone solution were used as samples in the study of spectral shifts and investigations on fluorescence quenching. The chlorophyll- doped samples were utilized for experiments on the relationship between concentration and fluorescence intensity. The elastomeric samples were also exploited as demonstration materials for introductory topics in fluorescence.