Simultaneous determination of citalopram and tadalafil by the second derivative synchronous fluorescence method in biological fluids; application of Box–Behnken optimization design

Abstract

This is the first study focusing solely on that determination of tadalafil in the presence of citalopram as an antidepressant drug. The determination in biological fluids of a co‐administered antidepressant drug and a sexual stimulation drug is a very critical and important step for psychotic and ischaemic heart disease patients, especially in cases of emergency and this requires therapeutic drug monitoring. A sensitive, efficient and rapid assay was selected satisfactorily and applied for simultaneous determination of citalopram and tadalafil either in their pure forms, in tablet dosage forms or in spiked human plasma. There was a large overlap for both drugs, forming the broad band found in conventional fluorescence spectra and their related synchronous fluorescence intensity. Therefore, the development of a highly sensitive second derivative synchronous fluorescence method was demonstrated that removed this overlap. The proposed method depended on measuring the amplitudes of the second derivative of synchronous fluorescence intensity at suitable wavelengths of 301 nm and 367 nm for citalopram and tadalafil at Δλ = 60 nm, respectively. Box–Behnken design as a response surface methodology was used to fit models and create an optimization process encompassing a set of factors and resulting in an optimum response value specifically designed for this method. Under optimum conditions, the linear dynamic ranges for citalopram and tadalafil estimation were 20–900 and 5–400 ng ml−1 with detection limits of 5.40 and 1.43 ng ml−1, respectively.

RPLC Method Development and Validation for the Simultaneous Determination of Selective Serotonin Reuptake Inhibitors in Tablet Formulations

“…In this study, studies were found for the determination of the selected SSRIs sertraline, citalopram, and fluvoxamine by the RPLC method for the determination of the compounds alone or simultaneously [20][21][22]. In addition, there are few studies on the determination of optimum conditions of compounds with the experimental design method related to this group [23][24][25]. For the qualitative determination of the selected compounds in this study, the optimum chromatographic condition was determined by examining the change in k values depending on the mobile phase pH at the constant column temperature and the organic modifier concentration in the mobile phase.…”

A synchronous spectrofluorometric technique for simultaneous detection of alfuzosin and tadalafil: applied to tablets and spiked biological samples

“…For determination of AFH, HPLC [15][16][17][18][19], spectrophotometric [20][21][22][23][24][25], spectrofluorometric [25][26][27][28] and voltammetric [29][30][31] procedures were revealed. For TDF determination, different HPLC [32][33][34], spectrofluorometric [35][36][37][38], spectrophotometric [35,[39][40][41][42] and voltammetric [43][44][45][46] methods were reported for its analytical quantitation.…”