THE NANOTECHNOLOGY IS CONSIDERED AS A TOOL TO OVERCOME ANTIBIOTIC-RESISTANT INFECTIONS. THE AIM OF THIS STUDY WAS TO INVESTIGATE THE ANTIBACTERIAL PROPERTIES OF QUANTUM DOTS (QDS) OF AU, AG, AND CU SUPPORTED IN CHITOSAN AGAINSTESCHERICHIA COLI(ATCC 25922),STAPHYLOCOCCUS AUREUS(ATCC 29213), ANDSALMONELLA TYPHI(ATCC 9993) STRAINS. THE QDS WERE SYNTHESIZED BY THE METHOD (CHEMICAL LIQUID DEPOSITION, CLD) USING 2-ETHOXYETHANOL AS SOLVENT (1X10-3 MAPPROXIMATE DISPERSION CONCENTRATION). THEN, NPS SUPPORTED IN CHITOSAN WERE SYNTHESIZED BY SOLVATED METAL ATOM DISPERSION (SMAD) IN TWO CONCENTRATIONS, LABELLED [A] AND [B] (0.05 AND 0.1 G/L) FOR EACH METAL WITH CHITOSAN RESULTING IN AN AVERAGE SIZE OF AU10 +/- 2.0, AG6 +/- 1.3, AND CU10 +/- 2.4 NM, RESPECTIVELY. SEVERAL OTHER TECHNIQUES WERE PERFORMED SUCH AS TEM, SEM/EDX, TGA, DSC, AND FT-IR FOR CHARACTERIZING QDS. THE ANTIBACTERIAL ASSAY WAS PERFORMED WITH 8 AGENTS ON CULTURES OFE. COLI,S. AUREUS, ANDS. TYPHIBY DISK DIFFUSION, BROTH MACRODILUTION, AND DETERMINING DEATH CURVE TO THE MOST SENSITIVE PATHOGEN. THE ANTIBACTERIAL EFFECT OF THE NANOPARTICLES WAS COMPARED USING THE DIAMETER OF GROWTH INHIBITION ZONE BY AGAR DISK DIFFUSION AND THROUGH THE MINIMAL INHIBITORY CONCENTRATION (MIC) AND MINIMAL BACTERICIDE CONCENTRATION (MBC) OBTAINED BY MACRODILUTION IN BATCH CULTURE WITH AN INITIAL INOCULUM OF 5X10(5) CFU/ML. THE HIGHEST BACTERICIDAL EFFECT WAS OBTAINED WITH NANOPARTICLES OF AU, AG, AND CU (0.1 G/L) WITH MIC AND MBC OF 200 AND 400 MG/ML, RESPECTIVELY. THE GREATEST BACTERICIDAL EFFECT CONSIDERING THE THREE PATHOGENS TURNED OUT TO BE AG QDS (0.05 AND 0.1 G/L). A BACTERICIDAL EFFECT OF METAL NANOPARTICLES IS AFFECTED MAINLY BY THE ELECTRONEGATIVITY, THE CONCENTRATION OF NANOPARTICLES, AND THE BACTERIAL AGE CULTURE.

MONOMETALLIC AND BIMETALLIC NI AND SN CATALYSTS WERE PREPARED IN DIFFERENT RATIOS BY THE SOLVATED METAL ATOM DISPERSED (SMAD) METHOD FOR THE CATALYTIC HYDROGENATION OF ACETOPHENONE TO 1-PHENYLETHANOL. THE PREPARATION OF THE CATALYSTS WAS CARRIED OUT BY EVAPORATION OF NI AND SN METAL ATOMS AND SUBSEQUENT CO-DEPOSITION AT 77 K USING 2-ISOPROPANOL AS SOLVENT ON ALUMINA AND MAGNESIUM OXIDE AS SUPPORTS. X-RAY PHOTOELECTRON SPECTROSCOPY (XPS) ANALYSIS SHOWED A HIGH PERCENTAGE OF NICKEL ATOMS IN ZERO VALENCE, WHILE THE TIN PHASES WERE FOUNDED IN REDUCED AND OXIDIZED FORM. THE AVERAGE SIZE OF THE NANOPARTICLES MEASURED BY TRANSMISSION ELECTRON MICROSCOPY (TEM) RANGED FROM 8 TO 15 NM WHILE THE METAL DISPERSION ON THE SURFACE MEASURED BY HYDROGEN CHEMISORPTION RANGED FROM 0.07% FOR NI1% SN0.3%/MGO TO 3.2% FOR NI5%/MGO. THERMOGRAVIMETRIC ANALYSIS SHOWS THAT ?-AL2O3 CATALYSTS EXHIBIT HIGHER THERMAL STABILITY THAN MGO CATALYSTS. THE CATALYSIS RESULTS SHOWED THAT THE BEST SUPPORT IS MGO REACHING 66% CONVERSION IN NI5% SN0.5%/MGO CATALYST.

NERVE REGENERATION IS A BIOLOGICALLY COMPLEX PHENOMENON. ONCE THE NERVOUS SYSTEM IS DAMAGED, ITS RECOVERY IS DIFFICULT AND CAUSES A MALFUNCTION IN OTHER PARTS OF THE BODY THAT CAN OCCUR BECAUSE MATURE NEURONS DO NOT SUFFER CELL DIVISION. TO INCREASE THE PROSPECTS OF AXONAL REGENERATION AND FUNCTIONAL RECOVERY, RESEARCH HAS FOCUSED ON THE CONSTRUCTION AND DESIGN OF NERVE CONDUCTION CHANNELS OR GUIDE TUBES. THAT IS WHY A HIGH MOLECULAR WEIGHT CHITOSAN WAS USED AS A STARTING MATERIAL, WHICH WAS FIRST CHARACTERIZED BY THE FOLLOWING ANALYSES: MOISTURE, ASH, FTIR, TGA, TOTAL NITROGEN DETERMINATION, VISCOSITY FOR THE DETERMINATION OF THE AVERAGE MOLECULAR WEIGHT AND DEGREE OF DEACETYLATION BY POTENTIOMETRIC TITRATION. ONCE THE STARTING CHITOSAN IS CHARACTERIZED, TUBE-SHAPED BIOMATERIALS ARE PREPARED BASED ON A 4% W/V CHITOSAN SOLUTION, USING CH3COOH SOLVENT AT 1% V/V. CALCIUM GLUTAMATE IS ADDED TO 0.5% AND 1% W/V, NEUTRALIZING WITH NAOH 0.25N, AND THEN TAKEN TO THE MOLDS TO BE FROZEN AND SUBSEQUENTLY FREEZE-DRIED. FINALLY, THE MATERIALS ARE COATED WITH POLYLACTIC ACID, IN ORDER TO ACHIEVE A STRENGTHENING IN THE STRUCTURE OF THE MATERIAL. THESE MATERIALS ARE ALSO PREPARED IN A BIO CLEAN AREA. THE DIFFERENT MATERIALS ARE CHEMICALLY AND MORPHOLOGICALLY CHARACTERIZED BY FTIR, TGA, ATOMIC ABSORPTION SPECTROSCOPY, MECHANICAL PROPERTIES, MORPHOLOGY AND SOLUBILITY TEST.

THE NEED TO FIND NEW THERAPIES TO IMPROVE THE FUNCTIONING OF THE INJURED TISSUE HAS MADE EMERGE A MULTIDISCIPLINARY FIELD OF RESEARCH. FIELD THAT IS RELATED TO THE PROBLEMS THAT EXIST FOR TRANSPLANT TO A PATIENT WITH DEFECT IN THEIR TISSUES AND NERVES, THESE TRASPLANTS ARE ONE OF THE MOST SERIOUS AND COSTLY HEALTH PROBLEMS. IN BIOMATERIALS RESEARCH HAS UNDERGONE A MAJOR EXPANSION, GENERATING A VARIETY OF STANDS OF DIFFERENT CHEMICAL NATURE. BIOCOMPATIBLE MATERIALS FOR HUMAN WHERE THEY SERVE THE SAME FUNCTION AS THE ACTUAL TISSUES AND ALSO EXHIBIT A TOTAL DEGRADATION IN THE BODY WITHOUT THE NEED FOR ANY OTHER POST-OPERATION TO REMOVE A DEVICE INSTALLED ON THE BONE REGION. BIODEGRADABLES AND BIOCOMPATIBLE COMPOSITES PREPARED WERE SUBJECTED TO STUDIES TO TEST THE BEST CONCENTRATIONS OF COMPONENTS OF THESE, FOR EXAMPLE CHITOSAN(CH), HYDROXYAPATITE(HAP) AND POLYLACTIC ACID(PLA), WITH THESE IS CREATED A MATERIAL THAT FULFILLS THE REQUIREMENTS FOR A GOOD RESULT IN BONE REGENERATION. THE RESULTS SHOW DIFFERENT ANALYSES OF THE COMPOSITES THAT THE PROPORTION OF CHITOSAN 4%, HYDROXYAPATITE 3% AND POLYLACTIC ACID 1.5% IS THE MORE APPROPRIATE COMPOSITION TO PRODUCE A BONE REGENERATION.

METAL COLLOIDS IN 2 PROPANOL USING NANOPARTICLES (NPS) OF COPPER, NICKEL AND COBALT WERE PREPARED BY CHEMICAL LIQUID DEPOSITION (CLD) METHOD. THE RESULTING COLLOIDAL DISPERSIONS WERE CHARACTERIZED BY TRANSMISSION ELECTRON MICROSCOPY (TEM). THE COLLOIDS WERE SUPPORTED IN CHITOSAN. THEN, MICROBIOLOGICAL ASSAYS WERE PERFORMED USING E. COLI AND S. AUREUS IN ORDER TO DETERMINE THE BACTERICIDE/BACTERIOSTATIC ACTIVITY OF NANOPARTICLES (NPS) TRAPPED OR CHELATED WITH CHITOSAN. FINALLY, THE TOXICITY OF THE METAL COLLOIDS CU, NI AND CO WAS TESTED. BIO-ASSAYS WERE CONDUCTED IN THREE DIFFERENT ANIMAL SPECIES. FIRST OF ALL ON EARTH WARMS (EISENIA FOETIDA) TO EVALUATE THE TOXICITY AND THE BIOCOMPATIBILITY OF CHITOSAN IN LACTIC ACID (1% AND 0.5%). SECONDLY BIO-ASSAY DONE IN FISHES (RAINBOW TROUT), THE LIVER TOXICITY OF NPS IN VIVO WAS EVALUATED. FINALLY, A BIO-ASSAY WAS CONDUCTED IN SPRANGE-DAWLEY RATS OF 100G WEIGHT, WHICH WERE INJECTED INTRAPERITONEALLY WITH DIFFERENT SOLUTIONS OF CHITOSAN METAL COLLOIDS. THEN, THE MINIMUM AND MAXIMUM CONCENTRATION WERE DETERMINED FOR COPPER, NICKEL AND COBALT. THE PURPOSE OF THE USE OF CHITOSAN WAS ACTING AS A CARRIER FOR SOME MAGNETIC NPS, WHICH TOXICITY WOULD ALLOW TO OBTAIN NEW POLYMERIC MATERIALS WITH POTENTIAL APPLICATIONS AS MAGNET FUTURE DRUGS CARRIER.

A PROTOTYPE OF ANTIFOULING PAINTS WAS PREPARED WITH A QS-CU (I)-FE (II) COMPLEX AS A POSSIBLE REPLACEMENT FOR TRADITIONAL ANTIFOULING PAINTS, WHICH CONTAIN A LARGE CONCENTRATION OF COPPER, FNDING THEM IN AN ORDER OF 10 - 30 % DEPENDING ON THE BRAND, AND IF IT IS WATER OR SOLVENT BASED. A QS-CU COMPLEX WAS PREPARED, WITH A SOLUTION AT 3% WITH ACETIC ACID, AND THEN FE2O3 WAS ADDED TO THE SOLUTION. FT IR ANALYSIS WAS CARRIED OUT, AS WELL AS ANALYSIS OF THE TGA AT THE QS AND THE COMPLEX WITH QS-CU, AND WITH THE SOLUTION, THREE DIFFERENT PAINTS WERE PREPARED. THOSE THAT VARIED VOLUMEN OF DIETHYLENE GLYCOL ADDED TO THEM. THE ANALYSIS OF THE PAINTS WAS CARRIED OUT, ONCE THE PAINT WAS PERVADED IN A NETWORK OF POLYAMIDE, THROUGH SEM WITH EDX AND TEM, WHICH WAS PURCHASED WITH THE COMMERCIAL PAINTS, WATER BASED AND SOLVENT BASED. ONE OF THE OBJECTIVES IS TO BE ABLE TO COMPARE THE COVERAGE OF THE NETWORK WITH THE COMMERCIAL PAINT, AND THAT OF THE COMPLEX QS-CU. THE RESULTS SHOWED THAT THE BEST PAINT OBTAINED WAS PAINT #2, FOUND TO BE SIMILAR TO THAT PERVADED WITH WATER BASED PAINT.

WOOD IS A GREAT MATERIAL, IT HAS A DISADVANTAGE OF EARLY DETERIORATION DUE TO EXTERNAL AGENTS. FOR THIS REASON, IT IS INTERESTING TO CREATE A NEW WOODEN PRESERVATIVE. IT WAS STUDIED ONE BASED ON A NATURAL POLYMER (CHITOSAN) AND NANOPARTICLES (SI AND TI). TESTS WERE CARRIED OUT TO CHARACTERIZE PHYSICAL (DENSITY, MOISTURE CONTENT, SWELLING AND ABSORPTION) AND MECHANICAL PROPERTIES (FLEXION, COMPRESSION AND HARDNESS) OF WOOD SPECIMENS WITH AND WITHOUT IMPREGNATION, AND THEIR JOINTS WITH TWO TYPES OF SELF-DRILLING SCREWS. SIMPLE AND LATERAL EXTRACTION TEST WERE CARRIED OUT. IMPROVEMENTS IN HARDNESS AND PERPENDICULAR COMPRESSION ARE HIGHLIGHTED OBTAINED, RESULTS INDICATE A STIFFENING OF THE FIBERS. THIS TREATMENT ACHIEVES THE MATERIAL CROSS SECTION HARDENING, COATING IT WITH COMPONENTS THAT HELP TO DELAY THE IGNITION AND PROVIDE GREATER DURATION AGAINST EXTERNAL AGENTS. FROM THE EXTRACTION OF SCREWS, THE IMPREGNATED WOOD ALLOWED MORE RIGID UNIONS, WITH SMALLER DISPLACEMENTS IN COMPARISON TO THE WOOD WITHOUT TREATMENT.

THE GRAPE TABLE IS THE MAIN FRESH FRUIT EXPORT OF CHILE. HOWEVER, IS AFFECTED IN THE FIRST PLACE BY FUNGAL PATHOGENS, RESULTING BETWEEN 10 % AND 15 % LOSSES IN PRODUCTION. THE COMMERCIAL USE OF BIOCIDES HAS A WEAKNESS GENERATING AN INCREASE IN DEMAND FOR NEW ANTIFUNGAL AGENTS. CHITOSAN AND CARBAMATE POSSESS FUNGICIDAL PROPERTIES;THEREFORE THE AIM OF THIS PAPER IS TO ANALYZE THE FUNGICIDAL ACTIVITY OF CHITOSAN ETHYLCARBAMATE. IN VITRO BIOASSAYS WERE CARRIED OUT TO EVALUATE THE EFFECTIVENESS OF THE FUNGICIDE TO CONTROL BOTRYTIS CINEREA AND FUSARIUM SPP. FUNGIES. THE CHEMICAL COMPOSITION OF CHITOSAN ETHYLCARBAMATE WAS DETERMINED PREVIOUSLY. THE FUNGI GROWTH CURVES AND FIT WITH THE PROGRAM DMFIT, WHICH USES THE BARANYI MODEL TO OBTAIN THE GROWTH PARAMETERS WERE STUDIED. THEN, WE ESTIMATED THE MIC (MINIMUM INHIBITORY CONCENTRATION) BY A MICRODILUTION METHOD. THESE DATA WERE ANALYZED BY SIMPLE LINEAR REGRESSION. GROWTH PARAMETERS OF FUSARIUM SPP SHOWS A GROWTH RATE OF 1.3 H-1, AND BOTRYTIS CINEREA OF 0.9 H-1, RESPECTIVELY. CHITOSAN ETHYLCARBAMATE WITH A MIC OF 1250 MG/L ON FUSARIUM SPP. AND B. CINEREA A MIC OF 1250 MG/L WERE OBTAINED. FINALLY, THE CHITOSAN ETHYL CARBAMATE FUNGICIDE, BIODEGRADABLE, IS A MORE ECOLOGICAL ALTERNATIVE TO THE CONVENTIONAL FUNGICIDES SUCH AS IPRODIONE, ZINEB, NABAM, MANEB AND THE TRADITIONAL BORDEAUX MIXTURE.

THIS RESEARCH AIMS AT CLARIFYING THE INFLUENCE OF THE GRANULOMETRY OF EXPANDED PERLITE, ON THE THERMAL CONDUCTIVITY, STRUCTURAL STRENGTH, DENSITY, AND WATER ABSORPTION OF LIGHTWEIGHT MORTARS. THREE ORIGINAL PERLITE GRADATIONS HAVE BEEN OBTAINED AND THREE PAIRS OF TWIN TEST MORTARS HAVE BEEN TESTED WITH THOSE GRADATIONS. SEM TESTS HAVE ALSO BEEN RUN TO CLARIFY THE INTERACTION, AT A MICROSCOPIC LEVEL, BETWEEN THE EXPANDED PERLITE AND THE CEMENT GROUTING. THE RESULTS INDICATE THAT THE MERE MANIPULATION OF THE GRANULOMETRY MAY HAVE A CONSIDERABLE AND VERY BENEFICIAL EFFECT ON THE MIXTURES PROPERTIES, SUCH AS THERMAL CONDUCTIVITY AND WATER ABSORPTION.

MICROCAPSULES (MC) BASED ON CHITOSAN (CH) AND INCLUDING NANO-MAGNETITE AND ERLOTINIB WERE SYNTHESIZED. THE MICROPARTICLES WERE CHARACTERIZED BY SEM, FT-IR AND TGA. THE PERCENTAGE OF ENCAPSULATION WAS DETERMINED, AS WELL AS ITS MICROBIOLOGICAL ACTIVITY. FINALLY, THE EFFECTIVENESS OF THE FORMULATION WAS EVALUATED IN TERMS OF CELL VIABILITY AND/OR TOXICITY WHEN COMPARED WITH THE REFERENCE DRUG. THE FORMULATION USED TO PREPARE THE MICROCAPSULES SHOWED SOME BACTERIOSTATIC PROPERTIES. THE CHARACTERIZATION OF MICROCAPSULES EXHIBITED AMORPHOUS SPHERICAL SHAPE AND AVERAGE SIZE OF 1.29, 1.58 AND 1.62 MM FOR CHITOSAN, CHITOSAN + NANOMAGNETITE AND CHITOSAN + NANOMAGNETITE + ERLOTINIB, RESPECTIVELY. THE INFRARED SPECTRA SHOWED CHARACTERISTIC BANDS OF THE ERLOTINIB AND MAGNETITE, CONFIRMING ITS INTERNALIZATION. THE THERMOGRAVIMETRIC ANALYZES INDICATED THAT THE MATERIALS DO NOT UNDERGO CHANGES AT OPTIMUM WORKING TEMPERATURES. THE HPLC ANALYSIS SHOWED A 52% OF ENCAPSULATION. FINALLY, THE FORMULATION PROBED HAD LOWER EFFECTIVENESS AND LESS CYTOTOXICITY, THAN THE DRUG WITHOUT ENCAPSULATING """"IN VITRO"""" STUDIES. FOR THAT REASON SEVERAL ASSAYS ARE IN PROGRESS.

CHITOSAN MICROSPHERES WERE SYNTHESIZED BY THE METHOD OF IONIC GELLING. THE OXOLINIC ACID WAS ENCAPSULATED IN CHITOSAN MICROSPHERES WITH DIFFERENT CONCENTRATIONS, WHICH WAS CORROBORATED BY FT-IR OF THE SPHERES SHOWING TYPICAL BANDS OF CHITOSAN AND THE ANTIBIOTIC. THE INCLUSION OF ANTIBIOTIC IN THE MICROSPHERES, WAS DETERMINED BY MEANS OF THERMOGRAVIMETRY SINCE THERE WERE TWO DECOMPOSITIONS TEMPERATURES CORRESPONDING TO DIFFERENT COMPOUNDS. AT SEVERAL CONCENTRATIONS OF OXOLINIC ACID CHITOSAN MICROSPHERES HAD DIFFERENT EXTERNAL MORPHOLOGY, BY MEANS OF SEM WAS OBSERVED THAT A HIGH CONCENTRATION OF ANTIBIOTIC GENERATED SMOOTH EXTERNAL TEXTURE, WHERE MOST OF THEM WERE SPHERICAL SHAPE. THE SOLUBILITY OF CHITOSAN MICROSPHERES WAS VERY LOW IN SEA AND NANOPURE WATER, SINCE THE PROTONATION AT BASIC PH OF CHITOSAN AMINO GROUP WAS VERY LOW, THE SOLUBILITY WAS LOWER THAN DILUTED ACETIC ACID. THE SOLUBILITY OF CHITOSAN AT DIFFERENT ONCENTRATIONS OF ANTIBIOTIC MICROSPHERES SHOWED A GAUSSIAN TENDENCY OF SOLUBILITY AT DIFFERENT ACID PH RANGES (HYDROGELS). THE OPTIMUM PH OF CHITOSAN SPHERES SOLUBILITY OCCURRED AT PH 3.5, WHICH WAS OBSERVED AT MAXIMUM POINT OF CURVE. CHITOSAN MICROSPHERES HAD DIFFERENT CONCENTRATIONS OF OXOLINIC ACID, BECAUSE RELEASING OF ANTIBIOTIC ONCENTRATION MAY OCCUR AND WHICH WAS MEASURED BY THE HPLC METHOD.

NON-SMALL CELL LUNG CANCER IS THE LEADING CAUSE OF CANCER-RELATED DEATHS WORLDWIDE. GEMCITABINE (GEM) IS AN EFFECTIVE CHEMOTHERAPEUTIC AGENT FOR TREATING THIS AND OTHER CANCERS. HOWEVER, THE NON-SPECIFIC TOXICITY OF GEM HAS PROMPTED A SEARCH FOR NOVEL CHEMOTHERAPEUTIC STRATEGIES. THE MAIN OBJECTIVE OF THIS WORK WAS TO OBTAIN MICROENCAPSULATED SYSTEMS LOADED WITH GEM, NANOMAGNETITE AND MICROZEOLITE IN CHITOSAN MATRIX BY SPRAY DRYING IN ORDER TO CHARACTERISE THEM AND TEST THEIR ACTIVITY ON LUNG CANCER CELLS. CAPSULE CHARACTERIZATIONS SHOWED SPHERICAL NANO-IN-MICROPARTICLES MEASURING 1.91 ?M ON AVERAGE WITH A ROUGH SURFACE AND CHARACTERISTIC SIGNS OF MATERIAL INTERACTION BY TEM AND FESEM-EDS. THE INTERACTION AND LOADING OF NANO- AND MICROPARTICLES IN THE CHITOSAN MATRIX WAS EVIDENCED BY FT-IR. % E.E. WERE OBTAINED. GREATER THAN 99.00 % IN ALL MICROENCAPSULES AND THE RELEASE OF THE GEM WAS SLOW AND CONTROLLED AT PH 7.4 AND 5.0 UP TO 24 H. MAGNETIC MOBILITY WAS DEPENDENT ON THE CONCENTRATION OF NANOMAGNETITE IN THE FORMULATION AND CELL VIABILITY WAS LOWER THAN THE PURE GEM CONTROL (1 MG/ML) IN BOTH CELL LINES (A549 AND H1299). NANO-IN-MICROENCAPSULATED SYSTEMS SHOW GREAT POTENTIAL FOR INHALED DELIVERY OF GEMS FOR THE TREATMENT OF NON-SMALL CELL LUNG CANCER.

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.

THE AIM OF THIS WORK WAS TO PREPARE AND CHARACTERIZE SEVERAL PROPERTIES OF AU NANOPARTICLES COLLOIDS PREPARED BY THE ?CHEMICAL LIQUID DEPOSITION? METHOD, WHICH INVOLVES THE CO-DEPOSITION OF METALLIC AU WITH ORGANIC VAPORS (2-ETHOXYETHANOL, 2-METHOXYETHANOL AND 1,3-BUTYLENGLYCOL AT 77 K). AUNPS SUPPORTED ON CHITOSAN WERE PERFORMED BY SOLVATED METAL ATOM DISPERSED METHOD. THEN, COLLOIDS WERE CHARACTERIZED BY TRANSMISSION ELECTRON MICROSCOPY (TEM), ELECTRON DIFFRACTION (ED), UV?VIS SPECTROSCOPY, ELECTROPHORETIC MOBILITY, PHYSICAL STABILITY, MEDIUM?FAR INFRARED SPECTROSCOPY AND THERMOGRAVIMETRIC ANALYSIS. THESE STUDIES HAD DEMONSTRATE THAT AU NANOPARTICLES SOLVATED WITH 1,3-BUTYLENGLYCOL AND 2-ETHOXYETHANOL, SHOWS HIGHER STABILITY, DUE TO THEIR HIGH DIELECTRIC CONSTANT AND A BETTER NPS SOLVATION. TEM ANALYSIS SHOWED A SIZE DISTRIBUTION BETWEEN 4.61 AND 48.8 NM. FROM ED, A FACE-CENTERED CUBIC STRUCTURE WAS FOUND. UV?VIS ANALYSIS SHOWED LOWER STABILITY OF NANOPARTICLES SOLVATED WITH 2-METHOXYETHANOL. FTIR SPECTRA SHOWED THAT THE SOLVENT WAS INCORPORATED AND SURROUND THE AU NPS. THE THERMOGRAMS SHOWS THAT THERMAL DECOMPOSITION OF AUNPS?CHITOSAN DECREASES WITH THE METAL PRESENCE. BIOASSAYS OF ACUTE TOXICITY ON FISHES WITH AUNPS?CHITOSAN WITH 1,3-BUTYLENGLYCOL WERE CARRIED OUT DUE TO THE LOWER TOXICITY. THE BIOASSAY SHOWED THAT 0.94 ML/L PRODUCE MORTALITY OF 50 % (LD 50) OF FISHES EXPOSED 96 H CALCULATED WITH A CONFIDENCE INTERVAL OF 0.810?1.148 ML/L.

THE SYNTHESIS OF AU, AG AND CU METAL NANOPARTICLES IN 2-ETHOXYETHANOL AND 2-PROPANOL SUPPORTED IN CARBON NANOTUBES IS REPORTED. THE SYNTHESIS WAS CARRIED OUT BY CHEMICAL LIQUID DEPOSITION (CLD) AT 77K TO OBTAIN METAL COLLOIDS. THE METAL SUPPORTED IN CARBON NANOTUBES WAS OBTAINED BY SOLVATED METAL ATOM DISPERSED (SMAD) METHOD. THE COMPOSITES WERE CHARACTERIZED BY ELECTRON MICROSCOPY WITH ELECTRON DIFFRACTION, SCANNING ELECTRON MICROSCOPY, ELEMENTAL ANALYSIS, THERMOGRAVIMETRY, INFRARED SPECTROSCOPY (FTIR). THE QUANTUM DOTS SIZE IN 2-PROPANOL AND CARBON NANOTUBES SUPPORTED ARE: SILVER 4.37 NM AND COPPER 2.56 NM. IN 2-ETHOXYETHANOL SOLVENT: SILVER 4.14 NM, COPPER 2.47 NM AND GOLD 5.30 NM. THE TRANSMISSION ELECTRON MICROSCOPY (TEM) IMAGES CONFIRM THE PRESENCE OF QUANTUM DOTS INSIDE AND OUTSIDE THE CARBON NANOTUBES. THE SAMPLES DEMONSTRATE A THERMAL STABILITY UNTIL 295°C. THE FTIR EXHIBIT THE PRESENCE OF SOLVENT RESIDUES IN THE SAMPLES. THE ELECTRON DIFFRACTION IS OBSERVED IN THE SILVER AND COPPER IN 2-PROPANOL SUPPORTED IN CARBON NANOTUBES AND IN THE SILVER SAMPLE FOR 2-ETHOXYETHANOL. THE HISTOLOGICAL ANALYSES OF RAINBOW TROUT (ONCORHYNCHUS MYKISS) AFTER BEING INJECTED WITH GOLD QUANTUM DOTS IN 2-ETHOXYETHANOL, IN CONCENTRATIONS 0.5 AND 0.3X10-3 M DO NOT EXHIBIT CELL DISRUPTION SHOWING HEPATOCYTES WITH MORPHOLOGY ACCORDING TO THE NORMAL FOR THAT SPECIE.

IN THIS WORK IT IS REPORTED THE SYNTHESIS OF GOLD NANOPARTICLES SUPPORTED IN SITU IN CHITOSAN BY SOLVATED METAL ATOM DISPERSION TECHNIQUE IN ORDER TO STUDY THE INCLUSION OF AU NANOPARTICLES IN THE BIOPOLYMER MATRIX. TO STUDY THEIR AGGREGATION ALONG TIME AND COMPARE WITH THE SYNTHESIS OF AU/2-PROPANOL COLLOID BY CHEMICAL LIQUID DEPOSITION TECHNIQUE. STUDIES OF AU NANOPARTICLES AGGREGATION ALONG TIME, SUPPORTED NANOPARTICLES AND COLLOIDAL NANOPARTICLES MORPHOLOGY WERE ALSO CARRIED OUT. THE CHARACTERIZATION OF AU NANOPARTICLES WAS PERFORMED BY TRANSMISSION ELECTRON MICROSCOPY, FIELD-EMISSION AND SCANNING ELECTRON MICROSCOPY, INFRARED SPECTROSCOPY, X-RAY DIFFRACTION, LIGHT SCATTERING AND ULTRAVIOLET?VISIBLE SPECTROSCOPY. METAL COLLOID SHOWED FRACTAL AGGLOMERATION TYPE AND DELAY TIME AFTER THE SYNTHESIS, THE AGGLOMERATION SIZE INCREASED TO FLOCCULATE. AU NANOPARTICLES SUPPORTED IN CHITOSAN SHOWED THE SAME SHAPE AS COLLOIDS AND FRACTAL AGGREGATION WAS MOSTLY DISTRIBUTED ON THE MATRIX.

A STUDY ON THE NANOPARTICLES SIZE AND THE ANTIBACTERIAL PROPERTIES OF HYALURONIC ACID (HA) DOPED WITH NANOPARTICLES IS REPORTED. NANOPARTICLES FROM GOLD, SILVER, COPPER, AND SILVER PALLADIUM WITH HA SUPPORT WERE PERFORMED. THE SOLVATED METAL ATOM DISPERSION (SMAD) METHOD WITH 2-PROPANOL AND HA WAS USED. HIGH-RESOLUTION TRANSMISSION ELECTRON MICROSCOPY (HRTEM), INFRARED SPECTROSCOPY (FT-IR), AND THERMOGRAVIMETRIC ANALYSIS (TGA) WERE CONDUCTED. THE AVERAGE SIZES OF NANOCLUSTERS WERE AS FOLLOWS: HA-AU = 17.88?NM; HA-AG = 50.41?NM; HA-CU = 13.33?NM; AND HA-AGPD = 33.22?NM. THE ANTIBACTERIAL ACTIVITY OF SOLUTIONS AND FILMS CONTAINING NANOPARTICLES AGAINST AMERICAN TYPE CULTURE COLLECTION (ATCC) BACTERIAL STRAINS ESCHERICHIA COLI (EC), STAPHYLOCOCCUS AUREUS (SA), STAPHYLOCOCCUS EPIDERMIDIS (SE), AND PSEUDOMONAS AERUGINOSA (PA) WAS DETERMINED. INHIBITION WAS OBSERVED FOR HA-AG, HA-CU, AND HA-AGPD. TOXICOLOGICAL TESTS WERE PERFORMED IN RATS THAT WERE INJECTED INTRAPERITONEALLY WITH TWO CONCENTRATIONS OF GOLD, COPPER, SILVER, AND SILVER-PALLADIUM NANOPARTICLES. NO ALTERATIONS IN HEPATIC PARAMETERS, INCLUDING ALT (ALANINE AMINOTRANSFERASE), GGT (GAMMA-GLUTAMYL TRANSPEPTIDASE) BILIRUBIN, AND ALBUMIN, WERE OBSERVED AFTER 14 DAYS. THESE FILMS COULD BE USED AS PROMOTERS OF SKIN RECOVERY AND GRADES I AND II CUTANEOUS BURNS AND AS SCAFFOLDS.

THE SYNTHESIS AND CHARACTERIZATION OF COPPER NANOPARTICLES SUPPORTED IN CARBON NANOTUBES IS REPORTED. COPPER NANOPARTICLES WERE OBTAINED BY THE CLD (CHEMICAL LIQUID DEPOSITION) METHOD CONSISTING OF REDUCED PRESSURE EVAPORATION OF METALS AND SUBSEQUENT LOW-TEMPERATURE CONDENSATION (77K) OF THESE VAPORS, WITH ORGANIC SOLVENT VAPORS. FROM THE REACTIONS OBTAINED BY THIS METHOD, COPPER COLLOIDS OF CONCENTRATIONS 10-3 AND 10-4 WERE SYNTHESIZED IN THE ORGANIC SOLVENTS 2-PROPANOL, 2-MERCAPTOETHANOL, 2-METHOXYETHANOL AND 2-ETHOXYETHANOL. THE SUPPORT OF COPPER NANOPARTICLES IN THE CARBON NANOTUBES WAS MADE BY SMAD METHOD WITH 24 HOURS UNDER AGITATION AND NITROGEN ATMOSPHERE BEFORE COLLECTING, OBTAINING COPPER NANOPARTICLE SOLIDS SUPPORTED IN CARBON NANOTUBES BY EVAPORATING THE SOLVENT EITHER 2-MERCAPTOETHANOL OR 2-ETHOXYETHANOL. COLLOIDAL AND SOLID DISPERSIONS WERE CHARACTERIZED BY DIVERSE TECHNIQUES, FOR COLLOIDAL DISPERSIONS UV-VIS SPECTROPHOTOMETRY, ELECTROPHORETIC MOBILITY, ELECTRON TRANSMISSION MICROSCOPY (TEM), ELECTRON DIFFRACTION AND STABILITY OVER TIME WAS USED. FAR-MEDIUM INFRARED SPECTROSCOPY (FT-IR) AND THERMOGRAVIMETRY (TGA) WERE USED FOR SOLIDS. THESE ANALYSES SHOW THAT CU COLLOIDS ARE RELATIVELY STABLE IN THE SOLVENTS USED, THE MOST STABLE DISPERSION WAS SYNTHESIZED IN 2-MERCAPTOETHANOL AND THE LESS STABLE IS SYNTHESIZED IN 2-METHOXYETHANOL, WHICH IS DEMONSTRATED IN UV SPECTRA. BY TEM, PARTICLE SIZES WERE STUDIED, BETWEEN 5.2 AND 17.2 NM. ELECTRON DIFFRACTION CONFIRMS THE PRESENCE OF COPPER. ANALYSIS OF ACTIVE SOLIDS SHOWS IN THE CASE OF FTIR THAT SOLVENTS ARE INCORPORATED INTO COPPER PARTICLES, AND IN THE CASE OF THERMOGRAMS IT IS SHOWN THAT THE SOLIDS SYNTHESIZED IN THE SOLVENT HAD GREATER THERMAL STABILITY 2-MERCAPTOETHANOL. IT WAS IMPOSSIBLE TO OBTAIN ELECTRON DIFFRACTION FROM THE COPPER NANOPARTICLES VISUALIZED BECAUSE THEY ARE INCORPORATED IN THE MULTIWALL NANOTUBES.