Miniaturization of spectrophotometry based on micro flow analysis using norfloxacin as less-toxic reagent for iron determination

A micro flow analysis (mu FA) system has been designed and fabricated for determination of total iron. The system consists of a microchannels fabricated by etching the polymethyl methacrylate (PMMA) by using laser ablation techniques and a sealed polydimethylsiloxane (PDMS) as top plate. The PMMA micro-flow was topped with a home-made polydimethylsiloxane (PDMS) micro-flow through cell, which was integrated with light emitting diode (LED) as light source and a USB 2000 spectrometer as detector. The proposed IRA system was applied to determination of Fe(III) using norfloxacin as a less-toxic complexing agent in an acetate buffer solution pH 4.0, resulting in a yellow colored complex which gave the maximum absorption at 430 nm. Under the optimum conditions, a linear calibration graph was obtained in the concentration range of 0.20-5.00 mg L-1. The limit of detection (LOD, defined as 3 sigma) and limit of quantification (LOQ defined as 10 sigma) were 0.12 and 0.45 mg L-1, respectively. The relative standard deviation (R.S.D.) for repeatability and reproducibility were less than 1.50% and 1.24% (n = 11) for 0.2 mg L-1 and 1.0 mg L-1 Fe(III), respectively. The proposed method was successfully applied to the determination of total iron in water samples, validated by the FAAS standard method after digestion by HNO3 and H2O2. (C) 2015 Elsevier B.V. All rights reserved.