| In recent years, the development of fast, precise, accurate andsensitive methodologies has become an important issue. However,despite the advances in the development of highly efficientanalytical instrumentation for the end-point determination ofanalytes in biological and environmental samples andpharmaceutical products, sample pre-treatment is usuallynecessary in order to extract, to isolate and to concentrate theanalytes of interest from complex matrices because most of theanalytical instruments cannot directly handle the matrix. A samplepreparation step is therefore commonly required. Based on theanalytical chemistry and separation science, the ability ofsurfactants and ionic liquids as green extractant for extractionsome drugs and food additives was studied. Fluorescence and highperformance liquid chromatography as the means of detection weredetermined. The high sensitivity fluorescence and high performanceliquid chromatography methods for the analysts in pharmaceuticalpreparations, biological fluids, herbal medicines and food wereestablished. The contents of this paper are as follows:(1) The principle of the methods of cloud point extraction andionic liquid micro-extraction was introduced. Reviewed these twomethods combined with variety of analytical tools for the determination of various inorganic and organic compounds.Advantages and disadvantages of existing methods of cloud pointextraction and ionic liquid extraction have been introduced.(2) A cloud-point extraction process using mixed micelle of theanionic surfactant sodium dodecyl sulfate and the nonionicsurfactant polyoxyethylene(7.5)nonylphenylether to extract twofluoroquinolone antimicrobial agents ofloxacin and gatifloxacinfrom aqueous media was investigated. The method is based on themixed micelle-mediated extraction of fluoroquinolones in thepresence of NaCl electrolyte as an inducing phase separation, thenspectrofluorimetric determination. The effect of different variablessuch as pH, PONPE7.5 concentration, SDS concentration, sodiumchloride concentration, cloud point temperature and time wasinvestigated and optimum conditions were established. At theoptimum conditions, the rectilinear calibration graphs wereobtained in the concentration range 0.1150 and 0.1250 ng ml-1ofofloxacin and gatifloxacin and the limits of detection was 0.04 and0.06 ng ml-1, respectively. The proposed procedures were appliedsuccessfully for the determination of the investigated drugs in theirpharmaceutical dosage forms, spiked urine and spiked plasmasamples with a good precision and accuracy.(3) The fluorescence spectral behavior of Prazosin Hydrochloridein anionic surfactant has been studied, and maximum extractionefficiency was observed. Accordingly, a method for thedetermination of Prazosin Hydrochloride using anionic surfactantSodium dodecyl sulfate (SDS) by fluorescence spectrometry aftercoacervation cloud point extraction was proposed. Under optimum conditions, Prazosin Hydrochloride was separated andpreconcentrated owing to the formation of stable micelle in thepresence of SDS. After phase separation, the surfactant-rich phasewas diluted with ethanol, and then determined by fluorescence. Theproposed method is simple, sensitive, and selective, and has a highenrichment factor, the method was successfully applied for thedetermination of the drug in pharmaceutical preparations and urine.(4) The fluorescence spectrum of berberine, palmatine,jatrorrhizine and coptisine in ionic liquids were studied, found thattheir fluorescence significant increased in ionic liquids and[C8MIM][PF6] could make the most increased of fluorescence.Further studies showed that these drugs could be extracted fromaqueous by [C8MIM][PF6] used the method of temperature-assistedionic liquid dispersive liquid phase microextraction and theenrichment factor and extraction recovery was 83.3 and 98.5%,98.1%, 98.3% and 98.8% respectively. Based on the [C8MIM][PF6]preconcentraton, separation and sensitized fluorescence for thesedrugs, a new selective and sensitive method for the determinationof the concentration of these four drugs in aqueous samples ispresented. At the optimum conditions, the linear relationship wasobtained i n the range were 0.8-130, 0.9-160, 0.7-140 and 0.6-110 ngmL-1, with a detection limit were 0.089, 0.112, 0.124 and 0.099 ngmL-1, respectively. The proposed method was successfully appliedfor the determination of the drug in pharmaceutical preparations,urine and serum samples.(5) An efficient in situ solvent formation microextraction (ISFME)combining high performance liquid chromatography was developed for the determination of sanguinarine and chelerythrine in Macleayacordata (Willd.) R. Br. and Chelidonium majus L and berberine,palmatine, and coptisine in medicinal plants and pharmaceuticalpreparations. The amount of ion-pairing agent (KPF6) was added tothe sample solution containing a water-miscible ionic liquid([C6MIM][Br]) to obtain a hydrophobic ionic liquid ([C6MIM]PF6),which acted as the extraction phase to replace volatile organicsolvent as an extraction solvent. Several important parametersinfluencing the extraction efficiency of IL-ISFME such as the typeand volume of IL, amount of KPF6, sample pH, extraction time,centrifugation time were optimized. The experimental resultsindicated that the proposed method was successfully applied to theanalysis of these alkaloids in medicinal plants and pharmaceuticalpreparations(6) A novel and simple microextraction method is introducedbased on manual shaking ionic liquid dispersive liquid phasemicroextraction (MS-IL-DLLME) for the determination of sixsynthetic food colorants such as Tartrazine, Amaranth, SunsetYellow, Allura Red, Ponceau 4R, Erythrosine. High performanceliquid chromatography coupled with UV detector was used for thedetermination of synthetic food colorants. The procedure is no needfor a dispersive solvent, heating, ultrasonic or additional chemicalreagents, in contrast to conventional IL-DLLME. In this method1-octyl-3-methylimidazolium tetrafluoroborate ([C8MIM][BF4]) wasdispersed into the aqueous sample solution as fine droplets bymanual shaking, and which promoted the analytes more easilymigrate into the ionic liquid phase. Some effective factors such as the volume of [C8MIM][BF4], sample pH, extraction time,centrifuging time have been investigated in detail. Under theoptimum experimental conditions, the proposed method hadexcellent detection sensitivity with limits of detection (LOD, S/N = 3)in the range of 0.015–0.32 ng mL-1. This method has been alsosuccessfully applied to analyze the real food samples and goodspiked recoveries over the range of 95.8–104.5% were obtained.
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