In vitro cytotoxicity of a supramolecular system composed by violacein complexed by -cyclodextrinthiol-protected gold nanoparticles (violacein@ -CD-S(CH 2 ) 6 -S-Au) on V79 and HL60 cell lines is described. The gold nanoparticles were prepared and modified in a single step involving reduction of tetrachloroaurate ions with sodium borohydride in the presence of thiol derivatized -cyclodextrin. Inclusion complexation of violacein into cyclodextrin cavities occurred by mixing an aqueous solution of the gold nanoparticles with an acetone solution of violacein, being evidenced by UV/visible absorption spectroscopy. According to cell viability measurements based on the MTT assay (3-(4,5-dimethylthiazole-2-yl)-2,5-biphenyl tetrazolium bromide) the supramolecular system was found to maintain the cytotoxic effects compared to free violacein on HL60 cells and in addition is less cytotoxic to normal (V79) cells.

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proporções molares de 1:1 e 1:2 foram analisados por microscopia eletrônica de varredura (SEM). O perfil de dissolução do BBAP e dos complexos de inclusões foram também avaliados durante 6 horas. Por microscopia eletrônica de varredura foi possível observar os complexos de inclusões formados entre BBAP e β-CD por co-evaporação nas proporções molares de 1:1 e 1:2. Como previamente detectado pela caracterização físico-química, na mistura física não se observou a presença de complexo de inclusão. Os estudos de dissolução mostraram que os complexos de inclusões 1:1 e 1:2 liberaram, respectivamente 49.07 ± 1.48 e 40.26 ± 3.90% de BBAP durante 6 horas. BBAP na forma livre foi menos solúvel que os complexos de inclusões e atingiu 9.00 ± 0.75% de dissolução. Os ensaios de citotoxicidade em macrófagos J774 e em uma linhagem de células fibroblásticas de pulmão (V79) indicaram que o BBAP não exibiu efeito tóxico adicional quando complexado com β-CD. Entretanto, os complexos de inclusões foram menos tóxicos para células V79 que BBAP na forma livre. Os complexos de inclusões BBAP/β-CD foram mais efetivos (CIM) que o composto livre em várias cepas de micobactérias. Resultados semelhantes foram observados sobre M. tuberculosis H37Rv intracelular para os complexos de inclusões BBAP/β-CD e rifampicina, uma droga antituberculose de primeira linha.Inclusion complexes and physical mixtures of isomeric mixture of E/Z (50:50) of 3-(4'-bromo-[1,1'-biphenyl]-4-yl)-3-(4-bromophenyl)-N,N-dimethyl-2-propen-1-amine (BBAP) and β-cyclodextrin (β-CD) in the molar proportion of 1:1 and 1:2 were analyzed by scanning electron microscopy. The dissolution behavior of BBAP and of the inclusion complexes were also evaluated for six hours. By scanning electron microscopy (SEM), it was possible to observe an inclusion complex formed between BBAP and β-CD by co-evaporation, either in the molar proportion of 1:1 or 1:2. In the physical mixtures, no complex was observed as previously detected by physicochemical analysis. The dissolution studies showed that the inclusion complexes BBAP/β-CD 1:1 and 1:2 released respectively 49.07 ± 1.48 and 40.26 ± 3.90% of BBAP during six hours. Free BBAP was less soluble than the inclusion complex and reached 9.00 ± 0.75% of dissolution. Biological assays, such as cytotoxicity to J774 macrophages and to a permanent lung fibroblast cell line (V79), indicated that the BBAP does not exhibit any additional toxic effect with the β-CD complexes. However, the complexes were less cytotoxic to V79 cells than the free form. The BBAP/β-CD inclusion complexes were more effective (MIC) than the free compound on several mycobacteria strains. Similar behavior was observed for BBAP/β-CD complexes and rifampicin, a front-line antitubercular drug, on M. tuberculosis H37Rv growing inside J774 macrophages.

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A polymeric micro- and nanosphere formulation using poly (epsilon-caprolactone) (PCL) to entrap an antituberculosis drug, isoniazid (INH), was developed and characterized. The microspheres were prepared by a solvent evaporation method using ethyl acetate, PCL and INH as the organic phase and water and Tween 40 as the aqueous phase. The nanospheres were prepared by a spontaneous emulsification solvent diffusion method using 40% ethanol in acetone (v/v), PCL and INH as the organic phase and water and Tween 40 as the aqueous phase. After freeze-drying, these systems were characterized by scanning electron microscopy (SEM), particle size analysis, determination of entrapped INH content, in vitro INH release and brine shrimp toxicity bioassay.