ZNAL2O4 AND MGAL2O4 THIN FILMS WERE GROWN ON SI(100) AND QUARTZ PLATE SUBSTRATES USING A PHOTOCHEMICAL METHOD IN THE SOLID PHASE WITH THIN FILMS OF BETA-DIKETONATE COMPLEXES AS THE PRECURSORS. THE FILMS WERE DEPOSITED BY SPIN-COATING AND SUBSEQUENTLY PHOTOLYZED AT ROOM TEMPERATURE USING 254 NM UV LIGHT. THE PHOTOLYSIS OF THESE FILMS RESULTS IN THE DEPOSITION OF METAL OXIDE THIN FILMS AND FRAGMENTATION OF THE LIGANDS FROM THE COORDINATION SPHERE OF THE COMPLEXES. THE OBTAINED SAMPLES WERE POST-ANNEALED AT DIFFERENT TEMPERATURES (350?1100 °C) FOR 2 H AND CHARACTERIZED BY FT-INFRARED SPECTROSCOPY, X-RAY DIFFRACTION (XRD), X-RAY PHOTOELECTRON SPECTROSCOPY (XPS), ATOMIC FORCE MISCROSCOPY (AFM), AND UV?VIS SPECTROSCOPY. THE RESULTS INDICATE THE FORMATION OF SPINEL-TYPE STRUCTURES AND OTHER PHASES. THESE CHARACTERISTICS DETERMINED THE QUALITY OF THE FILMS, WHICH WERE OBTAINED FROM THE PHOTODEPOSITION OF TERNARY METAL OXIDES.

THIS STUDY REPORTS THE ANTIBACTERIAL ACTIVITY OF AN OLIGOSACCHARIDE, PREPARED BY PARTIAL ACID HYDROLYSIS OF A NATIVE PAECILOMYCES SP. EXOPOLYSACCHARIDE, AND OF ITS AMINOGLYCOSYLATED DERIVATIVE, PREPARED BY REDUCTIVE ALKYLATION OF THE OLIGOSACCHARIDE, AGAINST E. COLI AND S. AUREUS.

PURE AND 10% PT-LOADED ZINC OXIDE THIN FILMS HAVE BEEN SUCCESSFULLY PREPARED BY DIRECT UV IRRADIATION OF BIS(?-DIKETONATE)ZINC(II) AND PT(II) PRECURSOR COMPLEXES SPIN-COATED ON SI(1 0 0) SUBSTRATES. THE SURFACE MORPHOLOGY OF THE FILMS WAS CHARACTERIZED USING ATOMIC FORCE MICROSCOPY (AFM) AND IT SHOWED THAT THE AS-PHOTODEPOSITED FILMS ARE AMORPHOUS AND HAVE A ROUGHER SURFACE THAN THERMALLY TREATED FILMS. THE CHEMICAL COMPOSITION OF THE FILMS WAS DETERMINED BY X-RAY PHOTOELECTRON SPECTROSCOPY (XPS). THE RESULTS INDICATED THE PRESENCE OF ZNO AND PTO ON THE SURFACE OF AS-DEPOSITED LOADED ZINC OXIDE FILMS. GAS SENSING TESTS REVEAL THAT AS-DEPOSITED 10% PT/ZNO FILMS EXHIBIT A BETTER RESPONSE THAN PURE ZNO FILMS TOWARDS 20 PPM CARBON MONOXIDE AT AN OPERATING TEMPERATURE OF 250 °C. THE SENSORS ALSO HAVE FAST RESPONSE AND RECOVERY CHARACTERISTICS.

THIS STUDY WAS CONDUCTED TO ASSESS THE CATALYTIC ELECTRODE SURFACE ADSORPTION AND CAPTURE PROPERTIES OF DIFFERENT METAL CHITOSAN DERIVATIVES IN AQUEOUS PHOSPHATE BUFFER SOLUTION (PH?=?7.3). EARLY, RECENT WORK SHOWED THAT THE RESPONSE OF IRON CHITOSAN COMPLEX WITH R?=?-CH3 ON THE PERIPHERY, OVER BLOOD RED CELLS IN PRESENCE OF SPHINGOMYELINASE C WAS PROTECTED. THE EFFECT OF OTHERS SUBSTITUENT (R?=?-BR, -CL, -F, NO2, -OCH3, -H) ON THE PERIPHERY OF THE SCHIFF BASE LIGAND DID NOT SHOW CORRELATION WITH THE OXIDATION OF SPHINGOMYELINASE C AND ITS BIOLOGICAL RESPONSE. FOR THIS REASON, VARIOUS ADSORBED METAL (M?=?FE OF RECENT WORK, CU, NI AND CO) COMPLEXES OF CHITOSAN AND SCHIFF BASES ON GLASSY CARBON ELECTRODE FOR THE OXIDATION OF SPHINGOMYELINASE C WERE INVESTIGATED AND COMPARED, EACH ONE WITH -CH3 GROUP ON THE PERIPHERY OF THE SCHIFF BASE. UV?VIS AND IR-TF SPECTROSCOPIES, ELECTROCHEMISTRY AND MICROSCOPY ASSAY WERE PERFORMED; THEN, THE METAL EFFECT UNDERLYING. FOR THE SCHIFF BASE, COBALT AND COPPER COMPLEXES DID NOT PROVED TO BE A REMARKABLE CELLULAR PROTECTOR IN PRESENCE OF THE ENZYME, BUT THE NICKEL COMPLEX SHOWED TO BE A CELLULAR PROTECTOR AT SHORT TIME, THIS CONCLUSION HELP TO PROPOSAL A REACTION MECHANISM FOR THE ELECTROCHEMICAL AND BIOLOGICAL STUDIES.

WE PROPOSE THE USE OF ALKOXIDE ?-DIKETONATES OF CE(III), ER(III), PR(III) AND YB(III) AS PRECURSORS FOR PHOTOCHEMICAL DEPOSITION OF CEO2:ER AND CEO2:ER/LN (LN = PR OR YB) THIN FILMS, FOLLOWED BY SUBSEQUENT ANNEALING AT 950 °C. THE MEASUREMENTS OF LUMINESCENT PROPERTIES REVEALED THAT CEO2:ER SAMPLES UNDER EXCITATION AT 980 NM EXHIBIT UP-CONVERSION EMISSIONS AT 540 NM AND NEAR INFRARED EMISSIONS CENTERED AT 1550 NM. WHEN CO-DOPING IS PERFORMED ON THE CEO2 FILMS, CEO2:ER/PR REDUCES ITS UP-CONVERSION CHARACTERISTICS AND THE NIR EMISSIONS INCREASE. HOWEVER, THE CEO2:ER/YB SAMPLES SIGNIFICANTLY INCREASE THE UP-CONVERSION PROPERTIES AND INHIBIT NIR EMISSIONS. DIFFERENT MECHANISMS BASED ON ENERGY TRANSFER PROCESSES ARE PROPOSED TO EXPLAIN THESE DIFFERENCES IN THE DEGREE OF INTENSITY OF THESE EMISSIONS.

ALZHEIMER

THE INSECTICIDAL ACTIVITY OF EXTRACTS OBTAINED FROM AERIAL PARTS OF TALGUENEA QUINQUENERVIS (GILL. ET HOOK) WERE EVALUATED USING BIOASSAY AGAINST LARVAE OF DROSOPHILA MELANOGASTER. ALL EXTRACTS TESTED HAD INSECTICIDAL ACTIVITY, THE MOST ACTIVE BEING THOSE THAT CONTAIN ALKALOIDS. FROM THE MOST ACTIVE FRACTION, IT WAS POSSIBLE TO IDENTIFY THE KNOWN ALKALOIDS COCLAURINE, ARMEPAVINE AND N-METHYLCOCLAURIN.

THE MEDICAL TREATMENT OF LAXOSCELISMS IS BASED SOLELY ON SUPPORTIVE MEASURES. ALTHOUGH EQUINE ANTISERUM FOR SPHINGOMYELINASE C (SMASE) AND D ISOMERS ARE AVAILABLE, IT IS NOT USED DUE TO THE RISK OF AN ANAPHYLACTIC REACTION AND ITS UNPROVEN EFFICACY. AS POTENTIAL ENZYME INHIBITORS, DERIVATIVES OF IRON CHITOSAN COMPLEXES WERE STUDIED (SHIFF BASE HAVING ?R = ?H, ?CL, ?BR, ?F, ?OCH3, ?CH3, ?NO2). THESE CHITOSAN COMPLEXES WERE CHOSEN BECAUSE THEY HAVE REVEALED GOOD RESULTS IN MEDICINE AND CATALYSIS DUE TO THEIR BIODEGRADABLE CHARACTERISTICS AND BIOAVAILABILITY. BESIDES CONSIDERING THAT THESE COMPLEXES HAVE NOT BEEN STUDIED IN RELATION TO THIS TOXIN. THE MECHANISMS UNDERLYING THE CATALYTIC AND CATCHER EFFECTS OF IRON CHITOSAN COMPLEXES WERE STUDIED USING ELECTROCHEMISTRY, UV?VIS SPECTROSCOPY AND MICROSCOPIC ASSAY AT PHYSIOLOGICAL PH. THE ELECTROCHEMICAL STUDIES SHOWED THAT ONE OF SEVEN SCHIFF BASES OF CHITOSAN ADSORBED ON GLASSY CARBON ELECTRODE WAS ELECTROCATALYTICALLY ACTIVE FOR THE OXIDATION OF SPHINGOMYELINASE AT 1.27 V, AND THAT ALLOWED PROPOSING A REACTION SCHEME FOR SMASE OXIDATION BY ADSORBED IRON COMPLEXES. ON THE OTHER HAND, EVEN THOUGH THE SPECTROSCOPIC STUDIES INDICATED THAT THERE WAS NO CHEMICAL BOND FORMATION BETWEEN THE COMPLEX AND SMASE IN SOLUTION, THE MICROSCOPIC STUDIES SHOWED THAT THIS COMPLEX PROVED TO BE A REMARKABLE CELLULAR PROTECTOR IN PRESENCE OF THE ENZYME. IN CONCLUSION, SHIFF BASE OF CHITOSAN WITH R = ?CH3 WAS THE ONLY ACTIVE COMPLEX IN FRONT OF SPHINGOMYELINASE C, PROTECTING RED BLOOD CELLS, ACCORDING TO OUR ELECTROCHEMICAL AND MICROSCOPIC STUDIES.

(BA, CA, SR)ZRO3?X THIN FILMS WERE PREPARED BY A PHOTOCHEMICAL METHOD USING THIN FILMS OF ?-DIKETONATE COMPLEXES AS PRECURSORS. THE PHOTOLYSIS OF THESE FILMS INDUCES THE FRAGMENTATION OF THE 2,2,6,6-TETRAMETHYL-3,5-HEPTANEDIONATE LIGAND AND THE PARTIAL REDUCTION OF METAL ION TOGETHER WITH VOLATILE ORGANIC COMPOUNDS AS SUB-PRODUCTS. WHEN THE METALLIC COMPLEXES ARE IRRADIATED IN AIR, THE FINAL PRODUCT OF THE REACTION ARE TERNARY METAL OXIDES. THE PHOTOREACTIVITY OF THESE FILMS WAS MONITORED BY FT-IR SPECTROSCOPY BY A PERIOD OF 72 H, FOLLOWED BY POST-ANNEALING AT 950 °C. X-RAY PHOTOELECTRON SPECTROSCOPY AND X-RAY DIFFRACTION TECHNIQUES WERE USED TO ANALYZE THE CHEMICAL COMPOSITION AND THE CRYSTALLINE STRUCTURE OF THE FILMS OBTAINED. THE RESULTS INDICATE THAT BA, CA, SR, ZR AND O ARE PRESENT IN THE FORM OF PEROVSKITA, PREFERABLY ADOPTING AN AMORPHOUS STRUCTURE. THE SURFACE MORPHOLOGY EXAMINED BY ATOMIC FORCE MICROSCOPY REVEALED A ROUGH AND IRREGULAR SURFACE. THE UV?VIS MEASUREMENTS SUGGEST A SLIGHT INCREASE IN THE OPTICAL BAND GAP VALUES, WHICH PROMOTE A REDUCTION OF THE INTERMEDIARY ENERGY LEVELS OR DEFECTS.

Y2O3 THIN FILMS DOPED WITH DIFFERENT CONCENTRATIONS OF ERBIUM IONS AND CO-DOPED WITH 10 MOL% OF YTTERBIUM WERE SYNTHESIZED BY A SOLID STATE PHOTOCHEMICAL DEPOSITION METHOD FOLLOWED BY A SUBSEQUENT CALCINATION PROCESS. THE PHOTO-REACTIVITY OF THE THIN FILMS WAS MONITORED BY FOURIER TRANSFORM INFRARED (FT-IR) SPECTROSCOPY. XRAY DIFFRACTION (XRD), X-RAY PHOTOELECTRON SPECTROSCOPY (XPS), SCANNING ELECTRON MICROSCOPY (SEM), UV-VIS SPECTROSCOPY AND PHOTO-LUMINESCENCE (PL) WERE EMPLOYED TO CHARACTERIZE THE SAMPLES. THE RESULTS REVEAL THAT Y2O3:ER FILMS UNDER 980 NM IRRADIATION EXHIBIT CHARACTERISTIC UP-CONVERSION EMISSIONS THAT ARE FOCUSED IN THE GREEN REGION OF THE SPECTRUM; THESE EMISSIONS ARE ASSIGNED TO THE (H-2(11/2), S-4(3/2)) -> I-4(15/2) TRANSITIONS OF THE ER3+ IONS. THESE EMISSIONS GREATLY INCREASE IN INTENSITY WITH THE ADDITION OF YB3+ IONS IN THE PREPARATION OF THE CODOPED FILMS. THIS PHENOMENON IS EXPLAINED BASED ON THE EFFICIENT YB3+ -> ER3+ ENERGY TRANSFER PROCESSES.

THIN FILMS OF ZRO2 LOADED WITH 10, 30 AND 50 MOL% SM WERE PREPARED BY A PHOTOCHEMICAL METHOD USING THIN FILMS OF METAL ACETYLACETONATE COMPLEXES AS PRECURSORS. THE PHOTOLYSIS OF THESE FILMS INDUCES THE FRAGMENTATION OF THE ACETYLACETONATE LIGAND AND THE PARTIAL REDUCTION OF METAL ION TOGETHER WITH VOLATILE ORGANIC COMPOUNDS. WHEN THE METALLIC COMPLEX IS EXPOSED TO AIR, THE PRODUCT OF THE REACTION IS METAL OXIDE. THE PHOTOREACTIVITY OF THESE FILMS WAS MONITORED BY FT-IR SPECTROSCOPY, FOLLOWED BY A POST-ANNEALING TREATMENT PROCESS. THE OBTAINED FILMS WERE CHARACTERIZED BY X-RAY PHOTOELECTRON SPECTROSCOPY AND ATOMIC FORCE MICROSCOPY.

THE CHITOSAN?(FE(II), CO(II), AND CU(II)) COMPLEXES WERE PREPARED BY MIXING CHITOSAN (CHI) POWDER WITH A SALICYLALDEHYDE (SAL, 5-HYDROGEN (?H)) AND THEIR 5-BROMO (?BR), 5-CHLORO (?CL), 5-METHOXY (?OCH3), 5-FLUORO (?F), 5-METHYL (?CH3), AND 5-NITRO (?NO2) DERIVATIVES (GROUPS R) AND MIXING THESE WITH FECL2 AND CUCL2 IN ETHANOL AND WITH CO(CH3COO)2 SOLUTIONS IN BUTANOL AT 80 °C OVER 8 H IN HETEROGENEOUS PHASE, FOLLOWED BY EXTRACTION WITH ETHANOL AND BUTANOL, RESPECTIVELY. THE COMPLEXES WERE CHARACTERIZED BY FTIR AND UV?VIS SPECTROSCOPY, ELEMENTAL ANALYSIS, AND CYCLIC VOLTAMMETRY. A LINEAR CORRELATION BETWEEN THE METAL FORMAL POTENTIAL VERSUS THE HAMMETT PARAMETERS OF THE SUBSTITUENTS WAS OBSERVED. THE ELECTRON-WITHDRAWING GROUPS SHIFT THE REDOX POTENTIAL TO POSITIVE VALUES, AS A RESULT OF LOWERING THE ENERGY OF THE HIGHEST OCCUPIED MOLECULAR ORBITAL. THE FORMAL POTENTIAL WAS USED AS A MEASUREMENT FOR THE DRIVING FORCE OF CHITOSAN COMPLEXES FOR REDOX REACTIONS.

CHITIN AND CHITOSAN ARE A CLASS OF METABOLITES THAT OCCURRING IN SOME FUNGI SPECIES THAT ARE ASSOCIATED WITH COMMERCIAL AND MEDICINAL PLANTS, THIS IS IN MUCOR SP. FOR EXAMPLE WITH AN AMPLE NUMBER OF BIOLOGICAL ACTIVITIES, BEING ANTIBACTERIAL AND ANTIFUNGAL ONE OF THE MOST IMPORTANT. INTO OUR PROGRAM OF SEARCH OF BIOPESTICIDES AND NATURAL COMPOUNDS WITH BIOLOGICAL ACTIVITIES, WE HAVE STUDYING CHITOSAN THAT WAS OBTAINED FROM THE CULTURE MEDIUM OF THE FUNGUS MUCOR RUOXII. CHITOOLIGOSACCHARIDES WERE PREPARED BY PARTIAL ACID HYDROLYSIS OF NATIVE CHITOSAN AND AN AMINOGLYCOSYLATED DERIVATIVE WAS OBTAINED BY REDUCTIVE AMINATION OF THE CHITOOLIGOSACCARIDE. THE SOLUBILITIES OF THESE COMPOUNDS WERE MEASURED AT DIFFERENT PHS AND ITS ANTIBACTERIAL ACTIVITY AGAINST ESCHERICHIA COLI (GRAM-NEGATIVE) AND STAPHYLOCOCCUS AUREUS (GRAM-POSITIVE). CHITOSAN AND THE DERIVATIVES TESTED EXHIBITED A GOOD ANTIBACTERIAL ACTIVITY AGAINST S. AUREUS.