HPLC method for determination of in vitro delivery through and into porcine skin of adefovir (PMEA)

Versatile chromatographic method for catechin determination in development of topical formulations containing natural extracts

“…CA recoveries were >85% for all drug concentrations and skin matrices evaluated. Our recovery results are above those of most of the scientific literature reports for experiments on drug extraction from the skin (Campos, Praça, & Bentley, ; Vávrová, Lorencová, Klimentová, Novotný, & Hrabálek, ).…”

Dimethylamino Acid Esters as Biodegradable and Reversible Transdermal Permeation Enhancers: Effects of Linking Chain Length, Chirality and Polyfluorination

“…The exposed area of 1 cm 2 was punched out and weighted. The skin sample was then extracted with 5 ml of the appropriate mobile phase (or PBS at pH 7.4 for adefovir) for 48 h. The recovery was 98±2% for theophylline, 101 ± 7% for indomethacin, 93 ± 1% for hydrocortisone and 97±2% for adefovir (28). The concentration of the drug in the extract was determined by HPLC.…”

“…The mobile phase consisted of 10 mM KH 2 PO 4 and 2 mM Bu 4 NHSO 4 at pH 6.0 with 7% of acetonitrile at a flow rate of 1.5 ml/min. The detector wavelength was set at 260 nm (28).…”

HPLC‐UV analytical method for determination of pizotifen after in vitro transdermal diffusion studies

“…(), which quantifies pizotifen malate in pharmaceutical solid dosage formulations. Our ultimate objective was to be able to quantify pizotifen in samples obtained directly from transdermal experiments without performing sample preparation or drug extraction, which is necessary when other analytical methods are employed (Femenia‐Font et al , ; Vávrová et al , ).…”

“…With the aim of identifying which method is most sensitive and specific, we have compared our approach with that developed by Abounassif et al (2005), which assesses the stability of some antihistaminic agents such as loratadine and pizotifen, and with the chromatographic approach of Rahman et al (2010), which quantifies pizotifen malate in pharmaceutical solid dosage formulations. Our ultimate objective was to be able to quantify pizotifen in samples obtained directly from transdermal experiments without performing sample preparation or drug extraction, which is necessary when other analytical methods are employed (Femenia-Font et al, 2005;Vávrová et al, 2007). The chromatographic method devised by Abounassif et al (2005) consists of a Bondesil CN column (250 Â 4.6 mm) with a 5 mm pore, a mobile phase of acetonitrile and buffer (0.01 M sodium acetate) 75:25 (v/v) at pH 3.5, a flow-rate of 2 mL/min, a wavelength of 254 nm, and an injection volume of 20 mL.…”