Letter to the Editor: Commentary on the history and quantitative nature of filter paper used in blood collection devices

"Our intent is to provide information supporting the use of DBS in many applications, based on 50 years of DBS use by newborn screening (NBS) laboratories in the USA." It is with great interest that we read Peter T Kissinger’s commentary about the use of dried blood spots (DBS) for pharmacokinetic assays and therapeutic drug monitoring published in the October issue of Bioanalysis. We appreciate Kissinger’s efforts to stimulate debate regarding the utility of DBS in these two types of applications. However, we would like to dispel some misconceptions about DBS and their filter paper matrix that readers, unaware of...