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1.
Sci Rep ; 8(1): 2590, 2018 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-29416103

RESUMO

This study is the first to report the successful development of a method to extract opium poppy (Papaver somniferum L.) DNA from heroin samples. Determining of the source of an unknown heroin sample (forensic geosourcing) is vital to informing domestic and foreign policy related to counter-narcoterrorism. Current profiling methods focus on identifying process-related chemical impurities found in heroin samples. Changes to the geographically distinct processing methods may lead to difficulties in classifying and attributing heroin samples to a region/country. This study focuses on methods to optimize the DNA extraction and amplification of samples with low levels of degraded DNA and inhibiting compounds such as heroin. We compared modified commercial-off-the-shelf extraction methods such as the Qiagen Plant, Stool and the Promega Maxwell-16 RNA-LEV tissue kits for the ability to extract opium poppy DNA from latex, raw and cooked opium, white and brown powder heroin and black tar heroin. Opium poppy DNA was successfully detected in all poppy-derived samples, including heroin. The modified Qiagen stool method with post-extraction purification and a two-stage, dual DNA polymerase amplification procedure resulted in the highest DNA yield and minimized inhibition. This paper describes the initial phase in establishing a DNA-based signature method to characterize heroin.


Assuntos
DNA de Plantas/química , DNA de Plantas/isolamento & purificação , Heroína/análise , Látex/análise , Ópio/análise , Papaver/química , Papaver/genética
2.
Biomacromolecules ; 15(7): 2573-82, 2014 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-24848134

RESUMO

Several critical aspects of cross-linked polyanhydrides made using thiol-ene polymerization are reported, in particular the erosion, release, and solution properties, along with their cytotoxicity toward fibroblast cells. The monomers used to synthesize these polyanhydrides were 4-pentenoic anhydride and pentaerythritol tetrakis(3-mercaptopropionate). Techniques used to evaluate the erosion mechanism indicate a complex situation in which several phenomena, such as hydrolysis rates, local pH, water diffusion, and solubility, may be influencing the erosion process. The mass loss profile, the release rate of a hydrophilic dye, the rate of hydrolysis of the polyanhydride, the hydrolysis product solubility as a function of pH, average pK(a) and its cytotoxicity toward fibroblast cells were all determined. The solubility of the degradation product is low at pH values less than 6-7, and the average pKa was determined to be ~5.3. The cytotoxicity of the polymer and the degradation product was found to be low, with cell viabilities of >97% for the various samples studied at concentrations of ~1000-1500 ppm. These important parameters help determine the potential of the thiol-ene polyanhydrides in various biomedical applications. These polyanhydrides can be used as a delivery vehicle, and although the release profile qualitatively followed the mass loss profile for a hydrophilic dye, the release rate appears to be by both diffusion and mass loss mechanisms.


Assuntos
Polianidridos/síntese química , Materiais Biocompatíveis/química , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Portadores de Fármacos/química , Humanos , Hidrólise , Cinética , Processos Fotoquímicos , Polianidridos/toxicidade , Polimerização , Compostos de Sulfidrila/síntese química , Compostos de Sulfidrila/toxicidade
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