In order to protect food from pathogenic microorganisms as well as to increase its shelf life while keeping sensorial properties (e.g. odor and taste), once the latter are one of the main properties required by spice buyers, it is necessary to analyze volatile formation from irradiation of medicinal and food herbs. The aim of the present study was to analyze volatile formation from 60 Co irradiation of Laurus Cinnamomum, Piper Nigrum, Origanum Vulgare and Myristica Fragans. Possible changes on the odor of these herbs are evaluated by characterizing different radiation doses and effects on sensorial properties in order to allow better application of irradiation technology. The samples have been irradiated in plastic packages by making use of a 60 Co Gamma irradiator. Irradiation doses of 0, 5, 10, 15, 20 and 25kGy have been tested. For the analysis of the samples, SPME has been applied, while for the analysis of volatile compounds, CG/MS. Spice irradiation has promoted mostly decrease in volatile compounds when doses of 5, 10, 15, 20 and 25kGy were used. For Laurus cinnamomum, the irradiation decreased volatile by nearly 56% and 89.5% respectively, comparing to volatile from a sample which has not been previously irradiated. Differently from other spices analyzed, irradiation on Myristica Fragans has increased volatile compounds except for 4-terpineol. The miristicine (toxic substance when in large quantities, commonly mentioned as narcotic) has increased by nearly 80%. For Origanum Vulgare and Piper Nigrum, significant decrease in volatile compounds have been found, mainly when it comes to 25 kGy irradiation. In general, results indicate loss of sensorial quality of spices.

The development of luminescent, non-toxic and biocompatible nanosensors are being used for marker and imaging of cells in cellular biology and ultrasensitive immunoassays. In this work, biological markers based on rare earths for detection of 17 β-estradiol (E2), in biological fluids (Plasmon), were studied. The precursor complexes based on rare earths (Eu 3+ and Tb 3+) were synthesized and characterized. The complex containing tta Eu 3+ and secondary ligand-TOPO-[Eu(tta) 3 (TOPO) 2 ] registered the highest luminescence efficiency among all other compounds studied and was chosen as luminescent probe for the following development stages of this work. This complex was doped into polymer matrices, PMMA and PHB, at different concentrations of doping by two different methods: cryoscopic nanoprecipitation and emulsion-diffusion technique. The PMMA polymer nanoparticles demonstrated higher luminescence efficiency when doped with 5% concentration of the precursor complex [Eu(tta)3(TOPO)2]. These nanoparticles were functionalized with 1,6 diaminohexane and later they were linked to a dialdehyde that will serve as a bridge in the reaction with the biological entities. These nanoparticles were functionalized with 1,6 diaminohexane and later they were linked to a dialdehyde that can serve as a bridge in the reaction with the biological entities. Due to the energy transfer Ac-Ac/nanosensor, the PHB polymeric nanoparticles showed higher luminescence intensity signal for the detection of 17-βestradiol by spectrofluorimetry. It can be concluded that the nanoparticles produced and tested in this work are strong candidates for the detection of 17β-estradiol in the blood plasma or others biological entities, presenting diagnostic options, an extremely important conduct for therapeutic direction. i LISTA DE FIGURAS FIGURA 1.1-A escala métrica de elementos naturais e dos produzidos pelo homem_________________________________________________________3 FIGURA 3.1-Tabela periódica dos elementos__________________________8 FIGURA 3.2-Representação esquemática (qualitativa) do mecanismo de transferência de energia entre um ligante orgânico e o íon Eu 3+ (CI= Conversão Interna/ CIS= Cruzamento Intersistema/ TE= Transferência de Energia)_____19 FIGURA 3.3-Diagrama de Energia dos íons TR 3+ obtidos a partir de cristais de LaF 3 __________________________________________________________21 FIGURA 3.4-Fórmulas estruturais dos ânions β-dicetonatos ACAC, TTA e DBM__________________________________________________________25 FIGURA 3.5-Estrutura molecular dos ligantes fosfinóxidos: Trifenilfosfinóxido (TPPO) e Tri-n-octilfosfinóxido(TOPO)_______________________________27 FIGURA 3.6-Estrutura molecular do precursor 2-(o-hidroxifenóxi)etil éter e do dibenzo-[18]-coroa-6_____________________________________________27 ii FIGURA 3.7-Estruturas de Éteres Coroa comuns (em destaque: DB18C6 e 18C6)_________________________________________________________29 FIGURA 3.8-Produção mundial de terras raras dos principais países produtores____________________________...