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Cisplatin (cis-diaminedichloroplatinum [II]) is a coordination compound, used in the treatment of several solid tumors. Cisplatin and its hydrolysis products exhibit a great pharmacological effect but are very toxic and probably carcinogenic. The present review summarizes the most important advances in the last years in the techniques employed for the detection and quantification of cisplatin and its hydrolysis products and in the different matrixes studied. The new emerging techniques and their modifications recently developed, fundamentally the combined use of detection and separation techniques for the analysis of platinum species and their impact on the speed, sensitivity and specificity of the analytical determination, with regard to the techniques used in the last century are discussed. High-Performance Liquid Chromatography and Capillary Electrophoresis, coupled with detection methods such as Mass Spectrometry, Inductively Coupled Plasma--Mass Spectrometry, Atomic Absorption Spectrometry and more recently, High-Field Asymmetric Waveform Ion Mobility Spectrometry are the methods more employed. The analysis of cisplatin and its hydrolysis products in new and more complex matrixes is also presented. [ABSTRACT FROM AUTHOR]

The effect of 03/H2O2 liquid phase molar concentration ratio at different pH on cyclophosphamide degradation rate was evaluated. The combination of O3/H2O2 leads to an increase of cyclophosphamide degradation rate, compared with single ozonation at the same pH and ozone dosages. It was found that cyclophosphamide degradation rate with O3/H2O2 depends on pH for the molar concentration ratios under study, the fastest degradation being observed for molar concentration ratio near 3.4 at pH 7 (80% degradation in 3 minutes). Pseudo-first order reaction rate constants for cyclophosphamide degradation were determined under the experimental conditions of this study. Cyclophosphamide was not detected after 15 minutes of reaction, but only a partial mineralization was obtained, evidenced by a total organic carbon removal lower than 60%. By attenuated total reflection infrared spectroscopy and electrospray ionization tandem mass spectrometry, 4-ketocyclophosphamide was identified as one of the main reaction products at pH 7 and 3.4 molar concentration ratio. [ABSTRACT FROM AUTHOR]

Ozone efficiency in the water treatment systems is widely published in national and international papers. The criteria design of the treatment plants have changed over the years with increasing knowledge about the mechanism through which ozone reacts with chemical and microbiological pollutants. It recognizes the existence of a relationship between morphological and physiological characteristics of microorganisms and their resistance to ozone. However, there are few studies reported about the mechanisms by which ozone inactivates microorganisms in aqueous media. The aim of this study was to evaluate the effect of ozone on cytoplasmic membrane and enzymes related to oxidative balance on two microorganisms: Escherichia coli ATCC 25922 and Salmonella enterica var. Thyphimurium ATCC 12 048. From a kinetic study was determined, the variation of the efflux of potassium, changes in SH groups and the action exerted by ozone on the enzymes catalase and superoxide dismutase. The results showed an involvement of SH groups present, mainly, in protein and the potassium efflux outside microbial cells, demonstrating that these compound are among the first targets of ozone on microorganisms. An increased activity of the catalase enzyme and a decreased activity of superoxide dismutase enzyme were observed. The decrease in the relationship between these two enzymes suggests that the antioxidant systems of microorganisms are not able to counteract the damage caused by ozone. [ABSTRACT FROM AUTHOR]

Introduction: Ozonized Sunflower Oil (OLEOZON ) is a registered drug developed at the Cuban Ozone Research Center and successfully employed in the treatment of different infection diseases. It is generally accepted, that the antimicrobial activity of ozonized vegetable oils it is related to the action of peroxidic compounds formed during ozone-vegetable oil reaction. The main targets of these peroxides on microorganism could be unsaturated lipids and proteins containing sulphydryl groups. Material and Methods: In this work, the polar fraction of OLEOZON® was isolated by a silicagel column chromatography method and the components of polar fraction were isolated by thin layer chromatography (TLC) and molecular exclusion - high performance liquid chromatographic (RP-HPLC). The components of polar fraction were characterized by the combination of nuclear magnetic resonance spectroscopy (NMR) and electro spray mass spectrometry (ESI-MS). S. Aureus ATCC 25923 and P. Aeruginosa ATCC 27853 strains were used to evaluate the in vitro activity (minimal inhibitory and minimal bactericidal concentrations) of OLEOZON® and its polar fraction. The content of potassium ions released to media by bacterial cells was employed as a criterion of alteration of the cell membrane permeability. Also, the total sulphydryl groups and the total protein content were measured. Results and Discussion: In the polar fraction of OLEOZON® are concentrated the oxidant and polar compounds formed. Different results were found for the two studied microorganism related to the different bacterial membrane composition. Conclusion: The main action mechanism of OLEOZON® again S. Aureus and P. Aeruginosa it is related to oxidative attack of peroxidic compounds to microorganism membranes. [ABSTRACT FROM AUTHOR]