Desenvolvimento de um método simples e de baixo custo para detecção de fluoxetina em produtos emagrecedores

Abstract

This work demonstrates the potential of batch injection analysis (BIA) system and square wave voltammetry (SWV) using boron doped diamond (BDD) as working electrode for the rapid screening of fluoxetine (FLU) in thermogenic supplements, manipulated and phytotherapeutic medicines for weight loss. The SWV technique was explored in stationary and hydrodynami mode (BIA-SWV) using the standard addition method. The proposed methods were developed using 0.1 mol L-1 H2SO4 as supporting electrolyte and the SWV optimized parameters were: step potential (∆Es) of 5mV; amplitude (a) of 40 mV and frequency of 60 s¬-1. In the proposed method using BIA-SWV, volume and speed of optimized injection were 150 µL and 75 µL s-1, respectively. The SWV method presented a linear range of 1 to 40 mg L-1 of FLU (r = 0.998). The proposed methods were applied in the analysis of four samples: Thermodrol®, green tea, chitosan, garcinia and a manipulated weith-loss medicine. For the SWV technique (stationary cell) the following results were obtained for the addition and recovery studies: Thermodrol®: 98 ± 6%; green tea: 112 ± 3%; weight loss medicine: 103 ± 2%; chitosan: 65 ± 3% and garcinia: 104 ± 4%. With BIA-SWV the following results were obtained for the addition and recovery studies: Thermodrol®: 34 ± 2%; green tea: 117 ± 2%; weight loss medicine: 93 ± 3%; chitosan: 68,5 ± 0,5% and garcinia: 70 ± 5%.