A UHPLC-UV Method to Quantify Skin Deposition and Transdermal Permeation of Tizanidine Hydrochloride

Abstract

Tizanidine hydrochloride is an α2-adrenergic agonist used for the symptomatic relief of spasticity associated with multiple sclerosis or with spinal cord injury or disease. The objective of this study was to develop an isocratic, robust and sensitive ultra-high performance liquid chromatography method using UV detection for use in a project to develop a transdermal therapeutic system to deliver tizanidine across the skin. Isocratic separation was achieved using a C18 column and a mobile phase comprising a 80:20 mixture of 0.004% trifluoroacetic acid in water and MeCN (pH* 3.2) at a flow rate of 0.2 mL min(-1) Tizanidine eluted at 1.499 min and the total run time was 2 min. The method was specific, robust and the response was accurate, precise and linear from 17.4 to 290 ng mL(-1) In contrast to existing methods, the method developed here was validated over a concentration range so as to include the low concentrations frequently observed in transdermal permeation studies and in samples extracted from the cutaneous matrix. Its suitability for use in transdermal permeation studies was subsequently tested and confirmed in preliminary experiments using porcine skin in vitro.

An isocratic RP-HPLC-UV method for simultaneous quantification of tizanidine and lidocaine: application to in vitro release studies of a subcutaneous implant

“…It is worth noting that the LOD and LOQ values in our study are relatively higher compared to previous publications. 2,39,52 Previously published studies often dealt with lower concentration ranges, 2,26 in nanograms 52,61 or employed more sensitive HPLC techniques like Ultra High Performance Liquid Chromatography (UHPLC), mainly because of the necessity to quantify the drug in complex samples such as blood or human serum. 39 The purpose behind validating this method was its intended application in in vitro release studies.…”

“…Accuracy and RSD values, indicative of precision, remained within acceptable limits, as the variability for all concentrations was below 4%. 52,56…”

“…Moreover, Analytical Methods Paper these ndings align with data previously published in the literature. 2,26,52 This HPLC method used methanol and water/TFA 0.1% as the mobile phase. It was decided to use methanol since TZ and LD are both soluble in it, and TFA 0.1% was added to the water phase to achieve a pH of 2.10.…”

“…Accuracy and RSD values, indicative of precision, remained within acceptable limits, as the variability for all concentrations was below 4%. 52,56 The aim of this study was to develop an analytical method to establish a sensitive and accurate approach for the detection and quantication of TZ and LD simultaneously. HPLC was chosen as the analytical technique for quantifying TZ-LD due to its capability to handle complex molecules with diverse polarity and molecular mass.…”

“…25,[31][32][33] Methods for the quan-tication of TZ, on the other hand, were described for analysing the drug alone, 34,35 concurrently with other drugs like muscle relaxants, 36 analgesics, [37][38][39] and anti-inammatories, [40][41][42][43][44][45][46][47][48] and from pharmaceutical formulations. 2,38,42,[44][45][46][47][48][49][50][51] Moreover, a method has been described for detecting TZ in skin deposition 52 and plasma. 35,41,49 While methods for detecting and quantifying both TZ and LD have been reported, none of these studies have presented an HPLC-UV method capable of simultaneously quantifying both.…”