Mucoadhesive gels designed for the controlled release of chlorhexidine in the oral cavity.

This study describes the in vitro/ex vivo buccal release of chlorhexidine (CHX) from nine mucoadhesive aqueous gels, as well as their physicochemical and mucoadhesive properties: CHX was present at a constant 1% w/v concentration in the chemical form of digluconate salt. The mucoadhesive/gel forming materials were carboxymethyl- (CMC), hydroxypropylmethyl- (HPMC) and hydroxypropyl- (HPC) cellulose, alone (3% w/w) or in binary mixtures (5% w/w); gels were tested for their mucoadhesion using the mucin method at 1, 2 and 3% w/w concentrations. CHX release from different formulations was assessed using a USP method and newly developed apparatus, combining release/permeation process in which porcine mucosa was placed in a Franz cell.

Control of transdermal permeation of hydrocortisone acetate from hydrophilic and lipophilic formulations.

The purpose of this research was the preparation of four formulations containing hydrocortisone acetate (HCA) for topical application, including two aqueous systems (hydrophilic microemulsion and aqueous gel) and two systems with dominant hydrophobicity (hydrophobic microemulsion and ointment). The formulations were tested for the release and permeation of HCA across an animal membrane. The release of HCA was found comparable for the four systems.

Fast dispersible/slow releasing ibuprofen tablets.

Eight formulations were developed containing ibuprofen in the form of orally disintegrating tablets. To prevent bitter taste and side effects of the drug, the drug was associated with Phospholipon 80H, a saturated lecithin, by wet granulation. The granules were then coated using different film forming agents (Kollicoat SR 30, Amprac 01, Kollidon 90F, Eudragit RD 100) obtaining four lots 1-4.

Effect of vehicles on topical application of aloe vera and arnica montana components.

In this study two types of gels and microemulsions are investigated for their ability to dissolve, release, and induce the permeation of helenalin, a flavonoid responsible for the anti-inflammatory activity of arnica montana extract, and aloin, an anthrone-C-glucosyls with antibacterial activity present in aloe vera extract. The release of these agents from each vehicle was followed by HPLC, and transcutaneous permeation was examined using a modified Franz cell and a porcine skin membrane. The study showed that a microemulsion can be a good vehicle to increase the permeation of helenalin, while the gel formulation, containing Sepigel 305, proved able to reduce the release and permeation of aloin, with a consequent activity limited to the surface of application, without any permeation.

Design and evaluation in vitro of controlled release mucoadhesive tablets containing chlorhexidine.

This investigation deals with the development of buccal tablets containing chlorhexidine (CHX), a bis-bis-guanide with antimicrobial and antiseptic effects in the oral cavity, and able to adhere to the buccal mucosa to give local controlled release of drug. A mucoadhesive formulation was designed to swell and form a gel adhering to the mucosa and controlling the drug release into the oral cavity. Some batches of tablets were developed by direct compression, containing different amounts of hydroxypropylmethylcellulose (HPMC) and carbomer; changing the amount ratio of these excipients in formulations, it is possible easily modulate the mucoadhesive effect and release of drug.

Solubility and transdermal permeation properties of a dehydroepiandrosterone cyclodextrin complex from hydrophilic and lipophilic vehicles.

The permeation ability of a compound is due principally to its concentration in the vehicle and to its aptitude to cross the stratum corneum of the skin. In this work ex-vivo permeation studies on newly developed formulations containing dehydroepiandrosterone (DHEA) were carried out to investigate vehicles that increase drug permeation through the skin. To enhance the solubility of DHEA, its complex form with alpha-cyclodextrin was used.

Skin permeation study of dehydroepiandrosterone (DHEA) compared with its alpha-cyclodextrin complex form.

Several studies have shown that dehydroepiandrosterone (DHEA) has promising uses in a large range of pathologies including age-related illnesses (osteoporosis, atherosclerosis), immune dysfunctions, and cancer. A long-term oral dosage form would be favorable, but this type of medication has not been developed yet because of the important first-pass effect and low and variable bioavailability. A proposed alternative strategy is the preparation of DHEA for transdermal permeation, allowing direct absorption in the systemic circulation.