1,721,162 research outputs found
Carrier tests to assess the effective sporicidal concentration of a liquid chemical disinfectant for a sanitization program.
No full textThe aim of the present investigation was to evaluate the microbial efficacy against highly resistant bacterial spores on different substrates using the lowest effective concentration of a market liquid sporicide based on peracetic acid. The validation was carried out following modified European regulatory agencies procedures or test methods and USP guidelines, employing carriers of materials usually treated with the sporicidal solution and present in grade A cleanrooms and spores of four different microorganisms: Bacillus subtilis and Clostridium sporogenes, both from the ATCC collection, and Bacillus cereus and Bacillus sphaericus as environmental isolates. A statistical evaluation of data was made to estimate the variance for different study conditions. The experiments highlighted that 70% suitable dilution of the ready-to-use peracetic acid solution was effective in both clean and dirty conditions, showing at least 2 log spore reduction after treatment. To obtain effective sporicidal action on the surfaces in cleanrooms it is sufficient to use a sporicidal solution with a ready-to-use concentration of 70% while ensuring a contact time of 10 min. In any case, the reduction of sporicide concentration ensures a high degree of disinfection and provides a consumption savings. LAY ABSTRACT: Wide-spectrum disinfectants are used in the pharmaceutical industry for the decontamination of work surfaces and equipment, but these products have some degree of toxicity for operators. This work arises from the needs of pharmaceutical companies to find the lowest effective concentration of sanitizers in order to reduce toxicity to personnel. The sanitizer used in the study was a market liquid sporicide based on peracetic acid. When we started our work no similar studies were reported in the literature, so we took European regulatory agencies and USP guidelines as a starting point, employing carriers of hard, non-porous materials usually treated with the sporicidal solution and present in sterile rooms and spores of four different microorganisms. The experiments highlighted that it is sufficient to use a 70% sporicidal solution concentration with a contact time of 10 min to reduce the number of spores to acceptable values for medicinal production. The reduction of sporicide concentration both ensures a high degree of disinfection and provides a safer working environment and consumption savings
Effect of chitosan and ts N-trimethyl and N-carboxymethyl derivatives on the ocular pharmacokinetics of ofloxacin in rabbits
No full textHydrogels for ocular delivery of pilocarpine: Preliminary evaluation in rabbits of the influence of viscosity and of drug solubility
No full textHydrogels, although seldom used in the ocular therapeutic practice, may offer various advantages over solutions and ointments. The present report describes the application of two distinct approaches, mucoadhesion and reduced drug solubility, to the development of improved hydrogels for delivery of pilocarpine. Five different polymeric materials, of natural, semi-synthetic and synthetic origin (xyloglucan gum, xanthan gum, pectin, hydroxypropylmethylcellulose and polyvinyl alcohol) were used at different concentrations to prepare two series of iso-viscous hydrogels (Series 1 and 2), each of which was characterized by a different apparent (pseudoplastic) viscosity (η' = 0.03 and 6.00 Pa·s at a shear rate, γ = 1.0 s-1). The more viscous gels (Series 2), tested in vitro for adhesion on hog gastric mucin (HGM), showed high work of adhesion (W) values. Series 1 and 2 hydrogels contained pilocarpine as the nitrate (PiNO3, 2.0% w/w), while a third hydrogel series (Series 3), having the same polymer composition and viscosity as Series 2, contained pilocarpine as a poorly soluble tannic acid complex (Pi/TA). All hydrogels were tested in vivo on rabbits for pilocarpine release to the tear fluid and for miotic effect. In two cases the transcorneal delivery of the drug was also evaluated. The overall biological activity increased in the order Series 1 < Series 2 < Series 3. The present preliminary results appear to indicate that the use of a sparingly soluble pilocarpine complex (Pi/TA) in combination with selected viscous, mucoadhesive hydrogels can result in prolonged activity and in increased bioavailability
Effects of chitosan and of its N-trimethyl and N-carboxymethyl derivatives on the ocular pharmacokinetics of ofloxacin in rabbits
No full textN-trimethylchitosan (TMCh) and N-carboxymethyl
chitosan (CMCh) were synthesized from a chitosan (Ch)
of high MW and deacetylation degree. 1% TMCh and, to
a lesser degree, 1% Ch HCl in ophthalmic solutions
enhanced transcorneal absorption of ofloxacin in rabbits.
1% CMCh did not enhance drug absorption, but mediated
zero-order absorption kinetics leading to a time-constant
effective antibiotic level in the aqueous
HPCH-based nail lacquers: “ex vivo” study on permeation of three antimycotics through bovine hoof membranes
No full textOcular permeation of liposome-encapsulated triamcinolone acetonide: evaluation on excised ocular tissues of rabbits
No full textPreparazione e valutazione di matrici polimeriche ottenute per liofilizzazione impiegabili per somministrazione oftalmica
No full textPreparazione e valutazione "in vitro" di un complesso mucoadesivo econazolo-polycarbophil
No full text- …
