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Montreal, Canada

Reanalysis of incurred samples showed that the bioanalytical method for the quantification of ramipril and ramiprilat was generating irreproducible results for ramiprilat. An additional peak interfering with ramiprilat was observed in the incurred samples but not in the calibrant and quality control samples. A similar interference was detected for ramipril, but it was chromatographically separated. Interferences were produced during sample preparation, which involves strong cation exchanger cartridges. The interfering products corresponded to the methylation of ramipril and ramiprilat glucuronide. Following this discovery, a reproducible method was developed and successfully validated for ramipril and ramiprilat. Additional stability tests were performed in the presence of glucuronide and diketopiperazine metabolites of ramipril and ramiprilat to demonstrate the method specificity. Source

Recently, incurred sample reanalysis (ISR) has become a requirement in bioanalysis. The general guidance recommends investigating ISR failure to evaluate the suitability of an analytical method. In the case of acceptable ISR evaluation, there were no precise recommendations for further testing when sporadic values were obtained. The ISR evaluation performed during a bioequivalence study for the anticonvulsant drug oxcarbazepine showed acceptable ISR results, but one particular chromatographic anomaly led to a thorough investigation. The finding of these tests showed that an oxcarbazepine phase II metabolite occasionally co-eluted with the drug and impacted oxcarbazepine's quantitation through in-source conversion. This paper demonstrates the necessity of rigorous interpretation of ISR results and close monitoring of all subject sample results. Source

The 19th International Reid Bioanalytical Forum was held in July 2011 in the UK. This open forum was an ideal meeting for extensive discussions on topics, such as global harmonization of bioanalytical guidance, in both formal and informal settings. Indeed, this meeting is well-known for its numerous networking opportunities during the 3-day conference and for an ethos of debate on practical solutions to problems encountered in bioanalytical science. Source

Ramagiri S.,AB SCIEX | Garofolo F.,Algorithme Pharma Inc.
Bioanalysis | Year: 2012

Background: Recent developments in LC-MS have turned it into a viable and valid alternative to ligand-binding assays. Large molecule bioanalysis by LC-MS is generally performed by tryptic digestion, purification and detection of one or more small signature peptides. High-resolution MS instruments offer quantification of intact small proteins or peptides and are able to increase the selectivity, while maintaining sensitivity. Results: Unlike multiple reaction monitoring assays, several factors affecting data processing were presented and the optimal parameters to consider during quantification method building were also demonstrated. MUC5AC-13 (MW 1709.8 Da), human hepcidin/LEAP-1 (MW 2797.4 Da), porcine calcitonin (MW 3604 Da) and chicken lysozyme (MW 14.3 kDa) were selected as model compounds and the possibility of intact peptide and small protein quantification, without tryptic digestion, was demonstrated. Conclusion: Selectivity and sensitivity were improved using different scan modes, such as TOF-MS and TOF-MS/MS. © 2012 Future Science Ltd. Source

Roberts C.A.,Durham University | Bernard M.-C.,Algorithme Pharma Inc.
Tuberculosis | Year: 2015

This study considers the biosocial profile of children admitted to the Philipson Children's Sanatorium at Stannington, Morpeth, Northumberland, England (1936-1954). The objective was to understand the differential impact of TB on male and female admissions at Stannington, according to a number of variables. A total of 1987 medical files were analysed. More females than males were admitted, peaks of admission at age six and 13 were documented, and the majority of children derived from poor urban areas. Over 60% (1199, 63.5%) of children had pulmonary TB, and 12% (230) had bone or joint involvement. The implementation of chemotherapy (streptomycin) at Stannington (1946), the end of the 2nd World War (1945), and the founding of the National Health Service (1948) did not have any great effect on the biosocial profile of children admitted to the sanatorium and treated (age, sex, origin, type of TB suffered, and socioeconomic status). Reasons for these finding are discussed. © 2015 Elsevier Ltd. All rights reserved. Source

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