Multiplexed extraction and quantitative analysis of pharmaceuticals from DBS samples using digital microfluidics.
BACKGROUND
Dried blood spot (DBS) sampling is emerging as a valuable technique in a variety of fields, including clinical and preclinical testing of pharmaceuticals. Despite this popularity, current DBS sampling and analysis processes remain laborious and time consuming. Digital microfluidics, a microscale liquid-handling technique, characterized by the manipulation of discrete droplets on open electrode arrays, offers a potential solution to these problems.


RESULTS
We report a new digital microfluidic method for multiplexed extraction and analysis of pharmaceuticals in DBS samples. In the new method, four DBS samples are extracted in microliter-sized droplets containing internal standard, and the extract is delivered to dedicated nanoelectrospray ionization emitters for direct analysis by tandem mass spectometry and selected reaction monitoring.


CONCLUSIONS
The new method allows for an order of magnitude reduction in processing time and approximately three-times reduction in extraction solvent relative to conventional techniques, while maintaining acceptable analytical performance for most drugs tested.
Department of Chemistry, University of Toronto, 80 St George St., Toronto, ON, M5S 3H6, Canada.
Nelson M
NM
Lafrenière
Steve C C
SC
Shih
Paul
P
Abu-Rabie
Mais J
MJ
Jebrail
Neil
N
Spooner
Aaron R
AR
Wheeler
D005591:Chemical Fractionation / Q000295:instrumentation / Q000379:methods*; D059788:Dried Blood Spot Testing / Q000379:methods*; D006801:Humans; D046210:Microfluidic Analytical Techniques / Q000295:instrumentation / Q000379:methods*; D004364:Pharmaceutical Preparations / Q000097:blood* / Q000302:isolation & purification*; D021241:Spectrometry, Mass, Electrospray Ionization
D004364:Pharmaceutical Preparations