The Release of Isoconazole Nitrate from Different Suppository Bases: In-vitro Dissolution, Physicochemical and Microbiological Studies

Abstract

The influence of the suppository base on the in-vitro release of isoconazole nitrate was studied by dissolution, physicochemical diffusion and microbiological disk-diffusion methods. Vaginal suppository formulations containing 25 mg isoconazole nitrate for local treatment of vaginitis were prepared by a fusion method, using different hydrophilic and lypophilic suppository bases (PEG 6000, PEG 4000, PEG 1500, Witepsol H15, Novata BD and Cremao). In-vitro release rates were examined by dissolution, physicochemical diffusion and microbiological disk-diffusion methods. In the physicochemical investigations the pH indicators (pH 1-14) erythrosin B, thymol blue, bromocresol green, chlorophenol red, phenol red, and alkali blue were added to agar gels. The discs were placed onto the agar gels and 21 h later, the coloured zone diameters were measured. In the microbiological investigations, the discs were put on the inoculated plates with the suspension of Candida albicans (Institute Pasteur 628). The inoculated plates were incubated at 37 degrees C for 3 days, then the diameters of inhibition zones were measured. In the dissolution investigations release rates were in the order PEG 6000> PEG 4000 > PEG 1500 > > Witepsol H15 > Cremao > Novata BD. The diffusion distance of isoconazole nitrate in the physicochemical investigation was in the order polyethylene glycols > Witepsol H15 > Novata BD. In the microbiological studies release rates were found with polyethylene glycols > Witepsol H15 > Novata BD > Cremao. The findings in the in-vitro studies suggested that polyethylene glycols are suitable bases for vaginal suppositories.

Pharmacokinetics and anti-hypertensive effect of metoprolol tartrate rectal delivery system

“…On the other hand, the water soluble bases gave higher drug release than the fatty bases (F1-F5) which may be due to the rapid dissolution and the rapid solubility of the water soluble base, wherein the drug can be released by both diffusion and erosion mechanisms (Hussain et al, 1980). These results are in a good agreement with many other investigators (Asikoglu et al, 1995;El-Nabarawi et al, 2003).…”

“…These results are in agreement with De Stoppelaar et al who stated that the metoprolol concentration in plasma and urine gave an indication for a partial avoidance of the first pass effect after rectal administration (De Stoppelaar et al, 1999). The reducing effect of MT suppository formulations on the blood pressure was ranked as follows: emulsion base (F11)4fatty base (F1)4PEG base (F10).These results revealed that the pharmacological effect of the drug was greatly influenced by the type and nature of the suppository base used (Asikoglu et al, 1995;Hosny et al, 1996). Moreover, MT formulated in the emulsion suppository base (F11) gave the highest significant antihypertensive effect in the rabbits at the end of the experimental time (6 h) compared to the other two tested formulations (F1, F10).…”

“…On the other hand, water soluble base liquefies by the absorption of water resulting in swelling and dissolution of the suppository. This leads to a dispersion process that is slower than the melting of the fatty base (Asikoglu et al, 1995;Hosny et al, 1996).…”

Preparation and evaluation of Ketotifen suppositories

“…From the results of the release of KT from different suppository bases can be ranked follows: Water soluble bases > Emulsion bases > fatty bases A good agreement of these results with those obtained by El-Nabarawi et al, [43] who worked on tramadol hydrochloride suppositories and reported that drug released more rapidly from hydrophilic bases than lipophilic ones and the release of isoconazole nitrate [44] was higher from hydrophilic bases compared to lipophilic ones.…”

W/O/W Multiple Emulsions Containing Nitroimidazole Derivates for Vaginal Delivery

“…Gamma scintigraphy has proven useful in in vivo evaluation of dosage forms administered by parentheral, rectal, buccal, nasal, pulmonary and ophthalmic routes and also vaginal formulations (Aşıkoglu, Ertan, and Coşar 1995;Fredricsson, Hangström, and Nord 2001). The rabbits are suitable models for the investigation of vaginal drug delivery because in the absence of male contact, the histology of the vaginal epithelium should be quite constant, resulting in expected minimal variability in membrane permeability behavior (Acartürk and Robinson 1996).…”