Sensitive HPLC Method With Fluorescence Detection and on-Line Wavelength Switching for Simultaneous Determination of Valsartan and Amlodipine in Human Plasma

Abstract

& This study describes the development and validation of a highly sensitive high-performance liquid chromatographic method with fluorescence detection and on-line emission wavelength switching for the simultaneous determination of valsartan (VAL) and amlodipine (AML) in human plasma. Irbesartan (IRB) was used as internal standard (IS). VAL, AML, and IRB were isolated from plasma by nonextractive procedure; simple protein precipitation with methanol. Separations were performed in low pressure gradient mode on Hypersil phenyl 120A analytical column using a mobile phase consisting of phosphate buffer (pH 4.0 AE 0.1):acetonitrile:methanol (60:30:10, v=v=v) at a flow rate of 0.8 mL=min. The detection of VAL and IRB (IS) was carried out at 253 nm (for excitation) and 374 nm (for emission). After elution of VAL and IRB, the detection wavelengths were switched on-line to 393 nm (excitation) and 446 nm (emission) for detection of AML. The linear ranges of the assay were 1-100 and 10-1000 ng=mL for VAL and AML, respectively. The limits of detection (LOD) were 0.3 and 1.6 ng=mL for VAL and AML, respectively. The intra-and inter-assay precisions were satisfactory; the relative standard deviations did not exceed 5.1%. The accuracy of the method was proved; the recovery of VAL and AML from spiked human plasma were 96.6-100.9 and 92.0-104.4% for VAL and AML, respectively. The method had higher throughput as it involved simple sample preparation procedure and short run-time (15 min). The results demonstrated that the proposed method would have great value in pharmacokinetic studies for VAL and AML.

Quantitative Determination of Amlodipine and Valsartan in Pharmaceutical Dosage Form

“…18 For VAL, UV spectrophotometry, [19][20][21][22] HPLC, 19,23 and HPTLC 24 methods were reported. Published methods for simultaneous determination of AMD and VAL include UV spectrophotometric, [25][26][27][28][29][30][31][32][33][34][35][36] spectrofluorimetric methods [37][38][39] , HPLC, 25,30,31,[40][41][42][43][44][45][46][47] TLC 44,48 and capillary electrophoresis. 49,50 The present research work is concerned with the development of two simple, accurate and sensitive spectrophotometric methods: absorption correction method (ACM) and dual wavelength method (DWM) for simultaneous determination of AMD and VAL with no need for prior separation.…”

Electroanalytical application of a boron-doped diamond electrode: Improving the simultaneous voltammetric determination of amlodipine and valsartan in urine and combined dosage forms

“…Several analytical methods to determine simultaneously AML and VAL in pharmaceutical formulations and biological fluids have been reported in the literature, including those capillary electrophoresis [3], chromatography [4][5][6][7][8][9][10], spectrofluorimetry [11], and spectrophotometry [12,13]. Some of these methods, such as chromatography and spectrophotometry, require a prior separation steps and tedious analytical process during analysis, the use of organic solvents, thereby generating high amounts of waste, time-consuming derivatization steps and high implementation costs, thus justifying the need for reliable, low cost and simpler methods.…”

Detection of vasodilator drugs through microwave spectroscopy of Au NP colorimetric probes using a microwave metallic photonic crystal-inspired resonant probe

“…3 Minoxidil is used to control blood pressure by relaxing and dilating the blood vessels, and it is always used in combination with beta-blockers and diuretics in order to prevent its side effects. 4 Several analytical techniques such as High Pressure Liquid Chromatography (HPLC), 5,6 Liquid Chromatography-Mass Spectrometry (LC-MS), 7,8 uorescence, 9,10 electrochemical, 11,12 and UV-visible spectroscopy 13,14 are reported for the analysis of two vasodilator drugs (amlodipine besylate and minoxidil) in pure pharmaceutical formulations and tablets. Unfortunately, these methods require more time for analysis, expensive instrumentation, and moreover, their applicability is limited only to the laboratory.…”

“…However, expensive fabrication, complex measurement setup, and sample preparation with remarkably sophisticated functionalization is required. Whereas, X-band (8)(9)(10)(11)(12) GHz) metamaterial sensor demonstrated by Lee and co-authors for specic binding between prostate-specic antigen (PSA) and antibody showed LOD up to 1 ng mL À1 . 28 Since the majority of the investigated microwave sensor devices are planar, in situ analysis cannot be performed into various biological and chemical assays.…”