CAFFEINE DETERMINATION BY FLOW INJECTION ANALYSIS EMPLYING BOVINE SERUM ALBUMIN AS FLUOROPHORE

FERNANDEZ, LILIANA; ALESSO, MAGDALENA

MICROCHEMICAL JOURNAL

ELSEVIER SCIENCE BV

Lugar: Amsterdam; Año: 2016 vol. 127 p. 156 - 159

0026-265X

A new methodology for caffeine determination was developed based on the quenching effect on fluorescentemission of the molecule of Bovine Serum Albumin at λem = 338 nm (λex=280). A flow injection dispositionwas designed improving significantly the sampling rate to 60 samples/h using potassium dihydrophosphate5 · 10−3 mol L−1 buffer (pH 6.8) as carrier and flow rate of 1.5 mL min−1. The experimental and instrumentalconditions that influence on analytical quality parameters were systematically investigated, as consider: buffernature and concentration, fluorophore nature and concentration, and carrier flow rate. The proposal is simple,fast, inexpensive and precise, with a linear range from 6.68 · 10−6 to 4.0 · 10−3 mol L−1 and SD of 0.0668,under optimized conditions. Methodology sensibility and selectivity allowed a variety of sample analyses. Itwas successfully applied to caffeine quantification in energy drinks, dietary supplements and sliming infusionsamples without previous treatment.