Fast Analysis of Water Samples for Trace Amount of Crystal Violet Dye Based on Solid Phase Extraction Using Nanoporous SBA-3 prior to Determination by Fiber Optic-Linear Array Detection Spectrophotometry

A solid phase preconcentration procedure using SBA-3 nanosorbent for the fast separation and preconcentration of crystal violet (CV) in water samples by fiber optic-linear array detection spectrophotometry (FO-LADS) is presented. Experimental parameters including pH, sample volume, amount of sorbent, type, volume, and concentration of eluent that affect the recovery of crystal violet have been optimized. Under optimized experimental conditions, analytical parameters including limit of detection, linear working range, and relative standard deviation have also been determined. A preconcentration factor of 200 was achieved in this method. In the initial solution, the detection limit for CV was found as 1.3？μg？L？1. Under optimal conditions maximum adsorption capacity was obtained as 344.83？mg？g？1. Also, the relative standard deviation was less than ±1.3% ( ). The presented procedure was applied to the determination of crystal violet in water samples (fish, fish farming water, and river water) with good results. 1. Introduction Crystal violet, a synthetic basic cationic dye, in Figure 1 imparts violet color in aqueous solution. The cationic dyes are more toxic than the anionic dyes [1], as these can easily interact with negatively charged cell membrane surfaces and can enter into cells and concentrate in cytoplasm [2]. Crystal violet is used in variety of ways: as a biological stain, dermatological agent, veterinary medicine, additive to poultry feed to inhibit propagation of mold, intestinal parasites and fungus, textile dying and paper printing, and so forth [3]. However, crystal violet (CV) is also carcinogenic and has been classified as a recalcitrant molecule since it is poorly metabolized by microbes, is nonbiodegradable, and can persist in a variety of environments [4]. Figure 1: Structural formula of CV. In response to concerns regarding the health risks associated with the use of crystal violet, even at trace levels, an increasing number of methods have been developed in recent years for its preconcentration and determination such as cloud point extraction (CPE), solid phase extraction (SPE), and rotating disk sportive extraction (RDSE) [5–7]. Among these preconcentration techniques, solid phase extraction is preferred by lots of researchers due to its advantages including simple and fast extractor system. It has a relatively high concentration factor and the ability of treating large volume samples free from contamination. The choice of the sorbent is a key point in SPE [8], because it determines the analytical sensitivity, affinity, capacity, and