P. Nicholas Shaw

Articles

The Importance of Complete Overlapping of Analyte and Internal Standard Peaks in Eliminating Matrix Effects with Liquid Chromatography–Mass Spectrometry (LC–MS)

Amitha K. Hewavitharana;P. Nicholas Shaw;H.D.C. Smyth;L.P. Samaranayake;H.M.H.N. Bandara

July 1st 2021

Ensuring complete overlapping (coelution) of analyte and internal standard peaks can be critical for eliminating matrix effects in LC–MS/MS analysis.

Strategies for the Detection and Elimination of Matrix Effects in Quantitative LC–MS Analysis

Swee K. Tan;P. Nicholas Shaw;Amitha K. Hewavitharana

January 14th 2014

We assessed a simple method based on recovery for the detection of matrix effects and two alternative methods for the rectification of matrix effects in LC–MS: standard addition and the coeluting internal standard method.

Inaccuracies in the Quantification of Peptides — A Case Study Using β-Endorphin Assay

H.M.D.R. Herath;P.J. Cabot;A.K. Hewavitharana;R.-R. Kim;P. Nicholas Shaw

August 1st 2013

This article describes possible sources of error that may contribute to significant inaccuracy in peptide assay methods: The fi ltration material (cellulose) used in sample clean up and the vial material (glass and plastic) used in LC analysis. This study is based on ?-endorphin but has relevance for most peptide assays.