Preconcentration of valsartan by dispersive liquid–liquid microextraction based on solidification of floating organic drop and its determination in urine sample: Central composite design

Abstract

In this work, a fast, easy, and efficient dispersive liquid-liquid microextraction method based on solidification of floating organic drop followed by high-performance liquid chromatography with UV detection was developed for the separation/preconcentration and determination of the drug valsartan. Experimental design was applied for the optimization of the effective variables (such as volume of extracting and dispersing solvents, ionic strength, and pH) on the extraction efficiency of valsartan from urine samples. The optimized values were 250.0 μL ethanol, 65.0 μL 1-dodecanol, 4.0% w/v NaCl, pH 3.8, 1.0 min extraction time, and 4.0 min centrifugation at 4000 rpm min(-1) . The linear response (r(2) = 0.997) was obtained in the range of 0.013-10.0 μg mL(-1) with a limit of detection of 4.0 ng mL(-1) and relative standard deviations of less than 5.0 % (n = 6).

Preparation of magnetic molecularly imprinted polymer for dispersive solid‐phase extraction of valsartan and its determination by high‐performance liquid chromatography: Box‐Behnken design

“…The equilibrium adsorption capacity of MMIPs was 157 mg/g, which was significantly outperformed than that of MNMIPs (68 mg/g). A comparison between the analytical performance data of this method and some microextraction techniques combined with HPLC for the extraction and determination of VAL can be seen in Supporting Information . As shown, the LOD and precision of the method were comparable with other microextraction methods.…”

“…Chromatograms of VAL extracted from spiked river water (0.10 µg/mL) at optimum extraction condition, mobile phase: acetonitrile: acetate buffer (50:50, v/v, pH = 4) with flow rate of 1 mL/min at 254 nm determination of VAL can be seen inSupporting Information Table S2[7,[21][22][23]. As shown, the LOD and precision of the method were comparable with other microextraction methods.…”

Development and Validation of a Stability-indicating RP-HPLC Method Using Quality by Design for Estimating Captopril

“…Response surface methodology (RSM) is a widely used approach for the simultaneous study of multiple input factors on a response. QbD methodology using RSM, a full or fractional factorial, central composite (CCD) [17] , Box-Behnken [18] or Doehlert [19] design can be used for the identification of experimental conditions for an optimized chromatographic separation. Identification of the factors that must be investigated and that affect key responses is necessary in order to define an experimental matrix that is fit for purpose so as to ensure that experiments are conducted in accordance and compliance with a well-defined experimental domain.…”

Determination Trace Levels of Vitamin C and Folic Acid in Urine Sample by Ultrasound-Assisted Dispersive Liquid-Liquid Microextraction Method Coupled HPLC-UV

“…It is as an effective preconcentration and separation of technique among these microextraction method for inorganic and organic species determination 15,16 . This method has a higher enrichment factor, is safe for use with hazardous samples, has a minimal cost because it consumes little reagent, is environmentfriendly, low cost and easier to incorporate into automated analytical methods 17,18 . The goal of this research was to develop a new and rapid method for the simultaneous determination of vitamin C and folic acid in human urine samples by high performance liquid chromatography-ultraviolet detection (HPLC-UV) after preconcentration by UA-DLLME.…”