Acne vulgaris (acne) is chronic inflammatory dermatosis which affects the pilosebaceous unit, with a varied clinical picture including inflammatory and non-inflammatory cutaneous lessions. This multifactorial disease mostly occurs in adolescents; however, it can also affect children and adults. Different therapy options for acne treatment exist, comprising topical, systemic and hormonal agents or a combination thereof. The choice of the therapy depends on various factors, for instance the severity and extent of the disease and site of involvement. Commonly used topical acne therapies include benzoyl peroxide, salicylic acid, antibiotics, retinoids, azelaic acid, sulfone agents and their combinations. Systemic antibiotics are indicated for use in moderate to severe inflammatory acne and should be used in combination with a topical retinoid and benzoyl peroxide. The available conventional formulations often cause side effects such as skin irritation, dryness, peeling, itching, leading to reduced patient compliance and compromised therapeutical efficacy. Novel drug delivery systems are promising option for improved acne treatment outcome, as they can diminish the side effects caused by the therapeutic agents or can modulate their properties and at the same time offering possibilities for modified release and improved skin penetration of the active substances. The cosmetics manufacturers implement micro/nanotechnology in their formulations, while patent protection for cosmetics has gained more importance over the past decades. This review focuses on micro/nanoparticulated carrier systems that can be used for acne treatment and the published patents concerning them.

Nanotechnology has a great potential for improving many areas of research and its applications, like nanoscale phenomena and processes, nanomaterials, nanoscale devices and instrumentation research. Nanoparticles, that are currently used, demonstrate many desirable properties for cancer management, considering their ability to accumulate in the specific parts of pathological areas and provide controlled drug release. Pharmaceutical nanocarriers can be used as a part of drug delivery systems for the purposes of therapy, diagnosis and imaging. Methods for nanoparticle manufacturing are: spray drying, aerosol flow reactor, mechanical methods (milling, homogenization under high pressure), precipitation techniques, techniques using supercritical fluids, methods for emulsion preparation and freezing (lyophilization). Future trends in the development of nanotechnology are expected to go towards additional decrease in dimensions of active and auxiliary compounds. The only way to achieve this is to combine methods used in medicine, engineering, materials studying, information technologies and physics. Keywords: nanoparticles, cancer, drug delivery

Suspension stability can be theoretically estimated prior to the beginning of the formulating process based on the solid phase particle size, liquid phase density, and viscosity. Stokes equation can be used to predict suspension stability in order to save time and resources. The examples of these calculations for the assessment of suspension physical characteristics are given in this article. One parameter that cannot be theoretically estimated with precision is flocculation/deflocculation. Flocculation can be experimentally determined using the "jar test," and it is a critical parameter for the substances showing inclination toward caking. Suspensions will sediment in time; however, it is their key feature to be able to redisperse in order to preserve the efficacy and proper dosage. Bismuth subnitrate is practically insoluble in water, which makes it convenient for oral pharmaceutical suspensions, rather than the other pharmaceutical forms. Like the other bismuth compounds, it tends to cake in aqueous medium. In order to prevent formation of the solid sediment, controlled flocculation of the suspended bismuth subnitrate particles is recommended. The effect of the excipients (sodium citrate, Tween 20, propylene glycol, microcrystalline cellulose) on the transmittance of the prepared suspensions and the quantity and characteristics of the formed sediment were evaluated. Suspensions containing sodium citrate, as well as the formulations with sodium citrate and microcrystalline cellulose, based on their transmittance characteristics, were determined to be flocculating suspensions, regardless of the sodium citrate concentration used. The highest affinity towards formation of flocculating suspensions, with the highest transmittance value had microcrystalline cellulose with 15% (w/w) sodium citrate.

Since the assay method for pantoprazole in pantoprazole pellets is not described in current pharmacopoeias (USP, BP), the aim of this work was to develop and validate a simple, precise and accurate method for determination of pantoprazole in pantoprazole pellets. Separation was achieved on a reversed-phase C8 column (250 x 4.6 mm i.d.; 5 a mixture of phosphate buffer pH 3.0 and acetonitrile as mobile phase, at a flow rate 2 ml/min and UV detection at 290 nm. The method was validated according to ICH Guidelines. Validation showed that developed method was valid and reliable for determination of active substance in pantoprazole

Oral administration of indomethacin has been limited by its poor water solubility. Cyclodextrins have been recognized as potential candidates to overcome the poor solubility of indomethacin through the formation of inclusion complexes. The aim of our study was to compare the dissolution profiles of pure indomethacin and its mixtures with α- and γ-cyclodextrins The inclusion complexes of indomethacin with α- and γ-cyclodextrins were prepared by direct mixing in dissolution vessel. Fixed volumes of the dissolution medium were withdrawn at 0,5; 1 and 4 hours. Dissolution tests were performed on the USP Apparatus 2, rotating speed 100 rpm at 37±0.5 ° C, 500 ml, distilled water and 0,1 M HCl solution). Quantification of dissolved indomethacin was performed by UV/VIS spectrophotometric method at the absorption maximum around 320 nm. The results were expressed as relative dissolution rate (ratio between indomethacin dissolved from its physical mixtures with α- and γ-cyclodextrins and that dissolved the pure drug). Relative dissolution rates of indomethacin in combination with α- and γ-cyclodextrins at the end of testing were in the range of 91,66 to 337,14 % (for α- cyclodextrin) and in the range of 128,57 to 301,92 % (for γ-cyclodextrin). The complexation of indomethacin with α- and γ-cyclodextrins resulted in the enhancement of dissolution rate.

Carbamazepine belongs to the class II biopharmaceutical classification system (BCS) which is characterized by a high per-oral dose, a low aqueous solubility and a high membrane permeability. The bioavailability of such a drug is limited by the dissolution rate. The present study deals with the formulations of immediate release tablets of poorly soluble carbamazepine. As model tablets for this investigation, two formulations (named "A" and "B" formulations) of carbamazepine tablets labeled to contain 200 mg were evaluated. The aim of this study was to establish possible differences in dissolution profile of these two formulations purchased from the local market. The increased crystallinity together with enlarged particle size, enhanced aggregation and decreased wettability of the drug, resulted in insufficient dissolution rate for formulation "B". From the dissolution point of view, this formulation was inferior to the formulation "A", due to the solubilization effect.

The objective of this work was to compare several profiles of dissolution data for metoprolol controlled release tablet formulations in order to identify possible changes in dissolution profiles of whole and scored tablets. Adequate design of score lines (on one or both sides) as well as the technology of preparation of tablet mixtures ensure forming a score line of adequate thickness, shape, size, curvature. According to the obtained results, this type of extended release formulation is eligible for splitting and use in therapy either as a whole or scored tablets.

Dissolution rate of two fluoroquinolone antibiotics (ciprofloxacin and moxifloxacin) was analysed in presence/absence of three antacid formulations. Disintegration time and neutralisation capacity of antacid tablets were also checked. Variation in disintegration time indicated the importance of this parameter, and allowed evaluation of the influence of postponed antacid-fluoroquinolone contact. The results obtained in this study showed decreased dissolution rate of fluoroquinolone antibiotics from tablets in simultaneous presence of antacids, regardless of their type and neutralisation capacity.