Magnesium ascorbyl phosphate vesicular carriers for topical delivery; preparation, in-vitro and ex-vivo evaluation, factorial optimization and clinical assessment in melasma patients.

Ascorbic acid (vitamin C) is an antioxidant that is widely used in cosmetics in skincare products. Due to the excessive low stability of ascorbic acid in cosmetic formulations, the stabilized ascorbic acid derivative, magnesium ascorbyl phosphate (MAP) was formulated as vesicular carriers; ethosomes and niosomes. The aim was to deliver MAP at the intended site of action, the skin, for sufficient time with enhanced permeation to get an effective response. Ethosomes were formulated using a full 32 factorial design to study ethanol and phospholipid concentration effect on ethosomes properties. Niosomes were formulated using 23 factorial designs to study the effect of surfactant type, surfactant concentration and cholesterol concentration on niosomes properties. The prepared formulations were evaluated for their Entrapment efficiency, particle size, polydispersity index, zeta potential and % drug permeated. The optimized ethosomal and niosomal formulations were incorporated into carbopol gel and evaluated for their permeation, skin retention and stability. A comparative split-face clinical study was done between the ethosomal and niosomal formulations for melasma treatment using Antera 3 D® camera. The optimized ethosomal and niosomal gels showed comparable controlled permeation and higher skin retention over their ethosomes and niosomes formulations respectively. Magnesium ascorbyl phosphate ethosomal gel showed clinically and statistically significant melanin level decrease after one month while MAP niosomal gel showed clinically and statistically significant melanin level decrease after six months. A combination of MAP ethosomes and niosomes could be promising skincare formulations for melasma and hyperpigmentation short and long-term treatment.

Gabapentin-saccharin co-crystals with enhanced physicochemical properties and in vivo absorption formulated as oro-dispersible tablets.

The physicochemical properties and in vivo absorption of a drug can be altered through cocrystallization with a suitable coformer. The aim of this study was to prepare and characterize Gabapentin (Gaba)-saccharine (sacch) sweet cocrystals for improvement of Gaba physicochemical properties, stability and in vivo absorption in addition to masking its taste. The prepared cocrystals were incorporated into oro-dispersible tablets as an attractive dosage form for pediatrics and adults. Gaba-sacch sweet cocrystals were prepared and characterized using FTIR, DSC, XRD and SEM analysis. They enhanced Gaba solubility and particle size distribution. Oro-dispersible tablets of the sweet cocrystals were prepared and evaluated in comparison to tablets prepared by Gaba-sacch physical mixture (PM). The tablets prepared by the cocrystals had lower wetting and disintegration time with enhanced drug release than those prepared with the physical mixture. The optimized formulation was evaluated for Gaba pharmacokinetics in rabbits in comparison to Gaba-sacch PM tablet and Gaba commercial oral capsules. This formulation had enhanced in vivo drug absorption through significant higher Cmax and AUC0-24 with shorter Tmax. The prepared Gaba-sacch sweet cocrystals oro-dispersible tablets, in addition to its enhanced in vitro and in vivo performance, can also enhance patient compliance through its palatable taste and ease of administration.

Formulation and stability study of chlorpheniramine maleate nasal gel.

Nasal administration has been of special interest in the last decade due to its feasibility and relative high bioavailability compared to the oral rout of administration. Our study aimed to develop a nasal gel formulation for an antihistaminic drug, Chlorpheniramine maleate (CPM), which suffers from poor oral bioavailability (25-45%) due to its first-pass metabolism in the liver. Different formulations of CPM nasal gels were prepared using different polymers in different concentrations, these gels were evaluated for their in vitro (physico-chemical properties, release, permeability and stability) to select the best formulation which subject to in vivo tests including mucociliary clearance and bioavailability, both in comparison to the solution and commercial tablet Allergyl.

Formulation of ketotifen fumarate fast-melt granulation sublingual tablet.

The purpose of this study was to prepare sublingual tablets, containing the antiasthmatic drug ketotifen fumarate which suffers an extensive first-pass effect, using the fast-melt granulation technique. The powder mixtures containing the drug were agglomerated using a blend of polyethylene glycol 400 and 6000 as meltable hydrophilic binders. Granular mannitol or granular mannitol/sucrose mixture were used as fillers. A mechanical mixer was used to prepare the granules at 40 degrees C. The method involved no water or organic solvents, which are used in conventional granulation, and hence no drying step was included, which saved time. Twelve formulations were prepared and characterized using official and non official tests. Three formulations showed the best results and were subjected to an ex vivo permeation study using excised chicken cheek pouches. The formulation F4I possessed the highest permeation coefficient due to the presence of the permeation enhancer (polyethylene glycol) in an amount which allowed maximum drug permeation, and was subjected to a pharmacokinetic study using rabbits as an animal model. The bioavailability of F4I was significantly higher than that of a commercially available dosage form (Zaditen solution-Novartis Pharma-Egypt) (p > 0.05). Thus, fast-melt granulation allowed for rapid tablet disintegration and an enhanced permeation of the drug through the sublingual mucosa, resulting in increased bioavailabililty.

Improvement of dissolution properties of Carbamazepine through application of the liquisolid tablet technique.

The aim of the work was to improve the dissolution properties of the practically insoluble antiepileptic drug, Carbamazepine (CBZ) by adopting the liquisolid compaction technique. Reported liquid load factors, and excipient ratios were used to calculate the required amounts of excipients necessary to prepare the compacts or tablets according to a mathematical model. Avicel PH 102, and Aerosil 200 were used as the carrier and the coating materials, respectively, and explotab was used as disintegrant to prepare four tablet formulae, out of which formula 1 was successfully compressed into tablets. The dissolution patterns of liquisolid CBZ tablets, carried out according to the USP, were comparable to those of Tegretol. The protection of male albino mice against the convulsion, induced by electroshock, was lower in case of liquisolid tablets compared to Tegretol suspension and tablets probably due to the precipitation of CBZ in the silica pores resulting from its high dose.