Pawel J Grobelny

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In this paper, we have investigated the mechanism of phototoxicity of fluvastatin, an 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitor, in human keratinocytes cell line NCTC-2544. Fluvastatin underwent rapid photodegradation upon Ultraviolet-A (UVA) irradiation in buffered aqueous solution as shown by the changes in absorption spectra.(More)
Fluvastatin is a member of the HMG-CoA reductase inhibitor family of drugs, commonly referred to as statins. It is generally known that, under physiological conditions, statins are susceptible to pH-dependent interconversion between their active (hydroxy acid) and inactive (lactone) forms. The mechanism of this interconversion, under both acidic and basic(More)
Nanosecond relaxation processes in sugar matrices are causally linked through diffusional processes to protein stability in lyophilized formulations. Long-term protein degradation rates track mean-squared displacement (⟨u(2)⟩) of hydrogen atoms in sugar glasses, a parameter describing dynamics on a time scale of picoseconds to nanoseconds. However,(More)
This study reports the results of an investigation of the phototoxicity mechanism induced by pitavastatin and its photoproducts, namely 6-cyclopropyl-10-fluoro-7,8-dihydrobenzo[k]phenanthridine (PP3) and 6-cyclopropyl-10-fluorobenzo[k]phenanthridine (PP4). The phototoxicity was tested in human keratinocytes cell lines NCTC-2544, and the results proved that(More)
Lyophilized proteins are generally stored below their glass transition temperature (Tg) to maintain long-term stability. Some proteins in the (pure) solid state showed a distinct endotherm at a temperature well below the glass transition, designated as a pre-Tg endotherm. The pre-Tg endothermic event has been linked with a transition in protein internal(More)
Recombinant human growth hormone (rhGH) was lyophilized with various glass-forming stabilizers, employing cycles that incorporated various freezing and annealing procedures to manipulate glass formation kinetics, associated relaxation processes, and glass-specific surface areas (SSAs). The secondary structure in the cake was monitored by infrared and in(More)
The aim of this study was to investigate the effects of solid carriers and processing routes on the properties of amorphous solid dispersions of itraconazole. Three solid carriers with a range of surface properties were studied, (1) a mesoporous silicate, magnesium aluminum silicate (Neusilin US2), (2) a nonporous silicate of corresponding composition(More)
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