Com in the last decades fluorene based materials

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Unformatted text preview: ll create stability of new metal complexes. In this project, a novel fluorene -based ligand with dibenzo-18crown-6 was synthesized by means of substitution reaction to bind fluorene acetic acid and 4, 4 1 13 diamino-dibenzo-18-crown-6. The resulted compound was characterized using; H NMR, C NMR, FTIR, CHN and GPC. The potential exploitation of photoluminescence properties of this class of ligands w as evaluated for novel materials for optoelectronic devices. ANA-P21 A SIMPLE ISOCRATIC HPLC ANALYSIS FOR DETERMINATION OF CATECHINS AND CAFFEINE IN GREEN TEA IN COMMERCIAL MARKETS IN MALAYSIA Nofrizal, *A. A. Rahim and B. Saad School of Chemical Sciences, Universiti Sains Malaysia, 11800 Pulau Pinang, Malaysia E-mail: afidah@usm.my A simple and fast HPLC method using a monolithic column for determining 8 catechins and caffeine with water-acetonitrile-methanol mobile phase system was developed. The catechins (gallocatechin, catechin, epicatechin, catechin galleate, epigallocatechin, epigallocatechin gallate, epicatechin gallate, gallocatechin gallate) and caffeine were separated by an isocratic flow in 6.8 min with flow rate of 1.3 -1 mL min . The microwave-assisted extraction (MAE) technique as used to extract the samples. The validity of this method was confirmed by the quantitative measurement of eight catechins and caffeine. The linearity of the calibration curves was investigated by injecting si x concentrations of standard −1 mixtures (0.1 - 100 mg L ). All the analytes showed good linearity with squared regression coefficient 2 (R ) ranging from 0.9991 to 1.0000. LOD and LOQ were in the range of 1.17 - 1.78 and 3.74 - 5.22, respectively. Good reproducibility of both peak areas (RSD ≤2.39 %) was found. Recovery studies were −1 carried out by spiking three concentrations (20, 40 and 100 mg L ) of a mixture of catechins and caffeine standards to green tea samples. Satisfactory recoveries for all green tea samples were obtained (94.7 - 106.3 %) 86 3rd ICYC 2010 Universiti Sains Mala...
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This note was uploaded on 02/17/2011 for the course CHEMISTRY 101 taught by Professor Csr during the Spring '11 term at University of Louisville.

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