Chitosan beads loaded with essential oils in cosmetic formulations.

The aim of this work is to evaluate the stability and release of chitosan beads loaded with volatile molecules of Mentha piperita essential oil (E.O.) in a cosmetic formulation. The ability of the beads to quickly release Mentha piperita E.O. during use of a cosmetic formulation such as a bath foam is also assessed. The chitosan beads were produced with three different chitosan dispersions gelled with two different gelling solutions: (a) a 10% solution of sodium hydroxide (NaOH) and (b) a 4% solution of sodium tripolyphosphate (TPP). A few properties of six bead samples loaded with Mentha piperita E.O. are assessed. The properties are morphology, size, swelling ability, encapsulation efficiency, stability in time, and fast release of Mentha piperita E.O. during the use phase of the cosmetic formulation.

Preservative systems containing essential oils in cosmetic products.

The aim of this study was to evaluate the antimicrobial activity of selected essential oils (Laurus nobilis, Eucalyptus globulus and Salvia officinalis), both alone and in combination, in cosmetic preparations characterized by an increasing risk of microbial contamination, i.e. an O/W skin cream, a hydrogel and a non-alcoholic hydrolyte. Their potential synergistic effect in combination with the usual cosmetic preservatives at low concentrations (up to 200-fold less than usual) was also investigated.

Stability studies of new cosmetic formulations with vegetable extracts as functional agents.

A formulation study, using increasing amounts of Sepigel 305 as an emulsifier, has been carried out to find new O/W emulsions and value their stability also in presence of vegetable extracts. Stability results have been compared with those obtained from formulations described in the National Formulary of Italian Pharmacopoeia X and functionalised by us with the same vegetable extracts. By using centrifugation and accelerated ageing tests capable of bringing out the gelling and thermostability properties of Sepigel 305, the study emphasised that the new gel emulsions have a greater stability compared to the other formulations.

New cycloalkylpyrazoles as potential cyclooxygenase inhibitors.

In this study some cycloalkyl-3-(N-substituted carbamoyl)-1-phenylpyrazoles have been synthesized in order to screen their capability to inhibit human cyclooxygenase. The synthetic pathway is based on the well known property of nitrilimines to undergo 1,3-dipolar cycloaddition reactions. The structures of all the synthesized compounds have been elucidated by means of both analytical and spectroscopic methods.

Determination of bezafibrate concentration by high performance liquid-chromatography in serum of rats treated with lead nitrate.

In the present study, the bezafibrate levels were measured in serum of rats treated with lead nitrate using a high performance liquid chromatography (HPLC) method. The results have shown that the peak corresponding to bezafibrate in the chromatogram is reduced in serum of rats treated with bezafibrate plus lead, indicating that lead treatment accelerates the metabolism of bezafibrate in rats.

Synthesis of cis- and trans- 2-arylmethylcycloalkylamines: potential dopaminergic agents.

This paper reports the synthesis and the study of a few new diastereomeric arylmethylcycloalkylamines, tested as potential dopamine receptor active agents. New procedures for the stereospecific synthesis of the arylmethylcycloalkylamines were successfully experimented. All the considered compounds did not show any appreciable dopamine receptor activity.

Effects of in-vitro activity of miconazole and ketoconazole in phospholipid formulations.

Antifungal agents are often used in liposomal formulations in order to improve their pharmacological activity, but how vesicle inclusion can actually affect this is still not fully understood. We report here the results obtained from evaluation of the in-vitro activity against Candida albicans ATCC E10231 of miconazole and ketoconazole in various vesicular and non-vesicular preparations, obtained from egg and soya phospholipids, using time-kill curves. In most cases inclusion of miconazole or ketoconazole in liposomes led to a delayed and decreased activity of the drugs, with detectable differences among the various phospholipid concentrations and different liposomal preparations (small unilamellar vesicle, liposomes, multilamellar aggregates and broken liposomal structures). The results obtained may be helpful in the study of new preparations of antifungal agents entrapped in liposomal structures.

HDL subfractions as altered in cancer patients.

Previous studies from the authors' laboratories have shown that cancer patients are characterized by lower levels of high-density lipoprotein cholesterol (HDL-C) compared with those of normal subjects. HDLs are a complex class of lipoproteins which can be divided mainly into two categories, HDL2 and HDL3, that have not only different lipid and protein composition but also different functions. Therefore, for a better understanding of the metabolism of HDL during tumour growth, the different subfractions of HDL (HDL2 and HDL3) were analysed in the serum of neoplastic patients using a rapid and simple high-performance liquid chromatography (HPLC) method for the analysis. The results obtained showed that serum from neoplastic patients exhibits a peculiar pattern in the distribution of HDL subfractions, consisting of a sharp decrease in HDL3 and a consequent increase of the normal HDL2/HDL3 ratio. It is suggested that evaluation of the HDL subfractions may be of clinical relevance for cancer status and that due to its simplicity, short analytical time and small sample volume required, the HPLC technique used in this study can be easily applied to routine analysis in cancer patients.

Macrocyclic polyesters. I. A novel class of 1,3-butandiol derivatives as potential antimicrobial agents.

This paper reports the synthesis of a novel class of macrocyclic tetraesters containing 1,3-butandiol sub-units by reacting the stannolan derivative of the diol with diacyl chloride. The structure of the possible isomers was assigned by spectroscopic data and comparison with samples otherwise prepared. Preliminary screening revealed that these compounds have low antimicrobial activity, although it is higher than that of the starting diol.

Laser-induced vaporization mass spectrometry of rifamycins.

The mass spectra of many rifamycins cannot be obtained by electron ionization (EI) owing to their thermal decomposition. When a laser beam is used to vaporize the sample through an optic fibre inserted in a hollow probe which reaches the sample cup, decomposition is minimized and the EI spectra show abundant molecular ions and fragments of structurally high diagnostic value. These ionic species are easily observed owing to the lack of chemical noise often present in soft ionization methods, such as direct liquid chemical ionization and fast atom bombardment.

Mass spectrometric behaviour of pentachlorophenyl beta-carbonylenolate phosphino nickel(II) complexes: An example of thermal generation of a nickel(III) species.

The mass spectral behaviour of pentachlorophenyl beta-carbonylenolate phosphino nickel(II) square planar complexes has been investigated under electron impact (EI) and field desorption (FD) conditions. The fragmentation has been interpreted on the basis of the B/E linked scans and mass-analysed ion kinetic energy (MIKE) techniques. The acetylacetonate diphenylphosphino complex was found to undergo a solid state reaction in the probe, which led to the generation in situ of a nickel(III) chloro complex. Careful control of instrumental conditions and computer-assisted EI measurements made it possible to characterize the addition products as [NiCl(C(6)Cl(5))(AcAc)PPh(2)Me] and to propose a mechanism for its solid state generation.

High-energy collisional spectroscopy in qualitative and quantitative analysis of diesel particulates.

High-energy collisional spectroscopy provides a powerful analytical method for the characterization of polynuclear aromatic hydrocarbons present in diesel particulates. The absence of any need for extraction procedures and the large amount of information available from collisional spectra makes this technique of great interest. In particular, 3-methylcholanthrene can be determined from the daughter spectra of its molecular ion, with methylene iodide as internal standard.