High sensitivity and analyte capture with desorption/ionization mass spectrometry on silylated porous silicon.
Silylation chemistry on porous silicon provides for ultrahigh sensitivity and analyte specificity with desorption/ionization on silicon mass spectrometry (DIOS-MS) analysis. Here, we report that the silylation of oxidized porous silicon offers a DIOS platform that is resistant to air oxidation and acid/base hydrolysis. Furthermore, surface modification with appropriate hydrophobic silanes allows analytes to absorb to the surface via hydrophobic interactions for direct analyte extraction from complex matrixes containing salts and other nonvolatile interferences present in the sample matrix. This enables rapid cleanup by simply spotting the sample onto the modified DIOS target and removing the liquid phase containing the interferences. This approach is demonstrated in the analysis of protein digests and metabolites in biofluids, as well as for the characterizing of inhibitors from their enzyme complex. An unprecedented detection limit of 480 molecules (800 ymol) for des-Arg(9)-bradykinin is reported on a pentafluorophenyl-functionalized DIOS chip.
Department of Molecular Biology, Scripps Center for Mass Spectrometry, Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, USA.
Sunia A
SA
Trauger
Eden P
EP
Go
Zhouxin
Z
Shen
Junefredo V
JV
Apon
Bruce J
BJ
Compton
Edouard S P
ES
Bouvier
M G
MG
Finn
Gary
G
Siuzdak
D000596:Amino Acids / Q000097:blood / Q000302:isolation & purification; D000818:Animals; D002417:Cattle; D006454:Hemoglobins / Q000737:chemistry; D007202:Indicators and Reagents; D012680:Sensitivity and Specificity; D012710:Serum Albumin, Bovine / Q000737:chemistry; D012825:Silicon / Q000737:chemistry*; D012822:Silicon Dioxide; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods*
D000596:Amino Acids; D006454:Hemoglobins; D007202:Indicators and Reagents; D012710:Serum Albumin, Bovine; D012822:Silicon Dioxide; D012825:Silicon