RESUMO
Chromatograms of sensitive HPLC methods often show disturbing peaks, which mostly can be traced back easily. But sometimes such peaks are difficult to reproduce and therefore hard to trace. This paper describes two cases where artifact peaks arose due to contamination by the septum and by the sampling equipment, respectively, leading to misinterpretation of impurities and erroneous quantification. Furthermore, troubleshooting and ways to overcome these deficiencies are outlined.
Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Artefatos , Sensibilidade e Especificidade , Espectrofotometria UltravioletaRESUMO
The functionally active part of influenza virus hemagglutinin was investigated through the synthesis of a series of peptides representing different parts of the intersubunit region. Secondary structure prediction, circular dichroism and Fourier transform infrared spectroscopic studies were undertaken to investigate the secondary structure of these peptides. The peptide fragments were found to adopt multiple conformations, depending on their concentration in solution, the presence of the non-ionic detergent octyl-beta-D-glucoside and the polarity of the solvent. The results of biological studies with these peptide fragments are discussed in relation to their conformation, as inferred from the spectroscopic analysis.
