Autonomous protein sample processing on-chip using solid-phase microextraction, capillary force pumping, and microdispensing.
A capillary force filling microsystem consisting of a chip-integrated solid-phase microextraction (SMEC) array and a microdispenser for sample purification and trace enrichment of peptides is described. The microextraction array was loaded with solid-phase media (50 microm Poros R2 beads) for purification and enrichment of proteomic samples. Samples bound to the SMEC were eluted in a volume of 200 nL. A piezo-electric microdispenser was docked to the array and the samples bound to the SMEC were eluted in a volume of 200 nL using capillary forces. The purified and enriched samples were dispensed onto the matrix-assisted laser desorption/ionization (MALDI) target, providing quality data from samples in the picomolar range. The nanoproteomic platform was compared to corresponding commercial preparation protocols, showing higher mass spectrometry (MS) signal intensities for peptides generated from an alpha-casein digest. The platform was also evaluated with regards to two-dimensional (2-D) gel-derived protein digests from both fibroblast and epithelial target cells.
Wallman
Lars
L
Department of Electrical Measurements, Lund Institute of Technology, Sweden. lars.wallman@elmat.lth.se
Ekström
Simon
S
Marko-Varga
György
G
Laurell
Thomas
T
Nilsson
Johan
J
D015180:Electrophoresis, Gel, Two-Dimensional; D004847:Epithelial Cells / Q000737:chemistry; D004867:Equipment Design; D005347:Fibroblasts / Q000737:chemistry; D006801:Humans; D046210:Microfluidic Analytical Techniques / Q000295:instrumentation / Q000379:methods*; D010446:Peptide Fragments / Q000302:isolation & purification*; D040901:Proteomics / Q000295:instrumentation / Q000379:methods*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
D010446:Peptide Fragments