Determination of drug concentrations using dried blood spots: investigation of blood sampling and collection techniques in Crl:CD(SD) rats

Abstract

Dried bloodspot (DBS) technology has been available for many decades but only in the last five years has it been considered for routine bioanalysis of blood samples collected on preclinical and clinical studies as part of a drug development programme. Advantages of using DBS versus typical plasma samples include smaller blood volumes, less processing of the samples (e.g. no centrifugation) and no requirement for storing or shipping of the samples at frozen temperatures. The current study compared blood concentrations (AUC 02t and C max ) from rats given an oral dose of acetaminophen (APAP) using two different sampling sites (caudal venepuncture versus tail snip), two different collection methods (3 separate 15 mL ethylenediaminetetraacetic acid [EDTA]-coated capillary tubes versus an EDTA integrated capillary blood collection system) and variability between blood spots on one card. There were no noteworthy differences (i.e. two-fold or greater) in blood concentrations of APAP using the different sites or methods. Furthermore, comparisons of the APAP blood concentrations in the original spot to a duplicate bloodspot from the same bloodspot card were within 12% of the original concentration.

Dried Blood Spot Analysis by Digital Microfluidics Coupled to Nanoelectrospray Ionization Mass Spectrometry

“…The authors of that work described a method relying on multilayer “hybrid microfluidics” for in-line analysis, in which samples were transferred from a digital microfluidic module (on the top of the device) to a microchannel (on the bottom of the device) with an integrated nanoelectrospray ionization (nESI) emitter for mass spectrometry. This method is an important step forward for the field, as the enthusiasm for automated processing techniques for analyzing DBS samples is well documented. − But the Jebrail and Yang et al technique suffers from a key limitation: devices formed in this manner require a complex series of fabrication and alignment steps prior to thermal bonding of the two substrates; this complexity may limit widespread application of the technique.…”

“…Dried blood spot (DBS) samples were formed in Toronto (University of Toronto) and in Ottawa (Newborn Screening Ontario, Children's Hospital of Eastern Ontario). For samples formed in Toronto, individual male units of blood in EDTA (K3) were purchased from Biochemed Services, Winchester, VA, and were fortified with SA (5,10,20,50, or 80 μM) and fixed amounts of 13 C 5 -SA (15 μM). Aliquots (100 μL) were spotted on filter paper (thickness ∼350 μm measured using a caliper) and dried at ambient temperature overnight.…”

“…Unfortunately, analytical technology has not kept pace with the surging popularity of DBS analysis for newborn screening and other applications. Although there is great interest in developing new techniques for analyzing DBS samples, − there are few automated solutions available, and most methods used now are manual, tedious, and slow . We report here a new method to analyze DBS samples for SA and other analytes.…”

Dried blood spots in toxicology: from the cradle to the grave?

“…precision capillaries). The blood collected with these devices can be used to generate DBS, or it can be frozen, diluted in another solution or centrifuged to prepare plasma (Smith et al, 2011, Stokes et al, 2011. Applications include pharmaco-and toxicokinetics, TDM and clinical, forensic and environmental toxicology.…”

Enhancing drug development and clinical studies with patient‐centric sampling using microsampling techniques: Opportunities, challenges, and insights into liquid chromatography‐mass spectrometry strategies

“…timepoints or alternative sample types such as biomarkers. 3,4 Traditionally, due to the limited total blood volume that can be drawn from rodents, the toxicokinetic (TK) profile is generated from a separate cohort of animals, known as a "satellite group", distinct from those used for pharmacokinetic (PK) studies. The advent of microsampling has dramatically reduced the need for the satellite groups, enhancing data quality by enabling the direct correlation of PK profiles and TK exposures within the same animals.…”