High-performance liquid chromatography with diode array detection method for the simultaneous determination of seven selected phosphodiesterase-5 inhibitors and serotonin reuptake inhibitors used as male sexual enhancers

Abstract

This work presents a simple, sensitive and generic high-performance liquid chromatography with diode array detection method for the simultaneous determination of seven drugs prescribed for the treatment of erectile dysfunction and premature ejaculation. Investigated drugs include the phosphodiesterase-5 inhibitors: sildenafil, tadalafil, and vardenafil, in addition to the selective serotonin reuptake inhibitors: dapoxetine, duloxetine, fluoxetine, and paroxetine. The drugs were separated using a Waters C8 column (4.6 × 250 mm, 5 μm) with the mobile phase consisting of phosphate buffer pH 3, acetonitrile and methanol in the ratio 60:33:7. The flow rate was 1.2 mL/min, and quantification was based on measuring peak areas at 225 nm. Peaks were perfectly resolved with retention times 3.3, 3.9, 6.4, 7.5, 9.5, 10.7, and 13.4 min for vardenafil, sildenafil, paroxetine, duloxetine, dapoxetine, fluoxetine, and tadalafil, respectively. The developed method was validated with respect to system suitability, linearity, ranges, accuracy, precision, robustness, and limits of detection and quantification. The proposed method showed good linearity in the ranges 5-500, 2-200, 2-200, 3-300, 1.5-150, 2-200, and 2-200 μg/mL for sildenafil, tadalafil, vardenafil, dapoxetine, duloxetine fluoxetine, and paroxetine, respectively. The limits of detection were 0.18-0.38 μg/mL for the analyzed compounds. The applicability of the proposed method to real life situations was assessed through the analysis of commercial tablets, and satisfactory results were obtained.

Method development for separating organic carbonates by ion‐moderated high‐performance liquid chromatography

“…The precision and accuracy for the developed method was studied as reported by Baker et al . The studies were conducted at three concentration levels (150, 1500, and 15,000 ppm) for each carbonate using three replicate determinations for each concentration through the same day.…”

Rapid detection of six phosphodiesterase type 5 enzyme inhibitors in healthcare products using thin‐layer chromatography and surface enhanced Raman spectroscopy combined with BP neural network

“…Up to now, various modern analytical techniques have been developed. The main methods are NMR spectroscopy , HPLC with diode array detection method , GC–MS , and LC–MS/MS . Though these methods are accurate, reliable, and highly sensitive, they are time‐intensive, and require highly trained personnel, and are not suitable for online screening of the PDE‐5 inhibitors in a large number of samples.…”

Solid‐phase extraction assisted dispersive liquid–liquid microextraction based on solidification of floating organic droplet to determine sildenafil and its analogues in dietary supplements

“…To date, LC coupled with UV detection and/or MS is the most effective method for the detection of sildenafil citrate and its analogues . MS not only provides high sensitivity and selectivity, but also gives molecular weight information, which makes the identification of target compounds more accurate.…”