ABSTRACT
Nowadays, biodegradable polymers such as poly(lactic acid) (PLA), poly(D,L-lactic--glycolic acid) (PLGA) and poly(-caprolactone) (PCL) remain the most common biomaterials to produce drug-loaded nanoparticles (NPs). Pipemidic acid (PIP) is a poorly soluble antibiotic with a strong tendency to crystallize. PIP incorporation in PLA/PLGA NPs was challenging because of PIP crystals formation and burst release. As PIP had a poor affinity for the NPs, an alternative approach to encapsulation was used, consisting in coupling PIP to PCL. Thus, a PCL-PIP conjugate was successfully synthesized by an original drug-initiated polymerization in a single step without the need of catalyst. PCL-PIP was characterized by NMR, IR, SEC and mass spectrometry. PCL-PIP was used to prepare self-assembled NPs with PIP contents as high as 27% (/). The NPs were characterized by microscopy, DLS, NTA and TRPS. This study paves the way towards the production of NPs with high antibiotic payloads by drug-initiated polymerization. Further studies will deal with the synthesis of novel polymer-PIP conjugates with ester bonds between the drug and PCL. PIP can be considered as a model drug and the strategy developed here could be extended to other challenging antibiotics or anticancer drugs and employed to efficiently incorporate them in NPs.
ABSTRACT
O consumo de alimentos vendidos nas ruas é um hábito cultural muito disseminado. Nos últimos anos, diversos fatores, particularmente sócio-econômicos, impulsionaram a comercializaçäo de alimentos nas vias públicas, em especial nos países em desenvolvimento. Entretanto, na maioria dos países ainda näo existe regulamentaçäo legal desta atividade e säo quase inexistentes os procedimentos de fiscalizaçäo. Analisa alguns dos aspectos sociais, econômicos, legais e higiênico-sanitários relacionados à venda de alimentos na rua, sugerindo estratégias para aprimorar esta atividade do ponto de vista da saúde pública.