title: Sample preparation for MALDI mass spectrometry using an elastomeric device reversibly sealed on the MALDI target.
abstract: A new method for improving low-concentration sample recovery and reducing sample preparation steps in matrix-assisted laser desorption/ionization mass spectrometry (MALDI MS) is presented. In the conventional approach, samples are typically desalted and/or concentrated with various techniques and deposited on the MALDI target as small droplets. In this work, we describe a new approach in which an elastomeric device is reversibly sealed on the MALDI target to form a multi-well plate with the MALDI target as the base of the plate. The new format allows a larger volume (5-200 microL) of samples to be deposited on each spot and a series of sample handling processes, including desalting and concentrating, to be performed directly on the MALDI target. Several advantages have been observed: (i) multiple sample transferring steps are avoided; (ii) recovery of low-concentration peptides during sample preparation is improved using a novel desalting method that utilizes the hydrophobic surface of the elastomeric device; and (iii) sequence coverage of the peptide mass fingerprinting map is improved using a novel method in which proteins are immobilized on the hydrophobic surface of the elastomeric device for in-well trypsin digestion, followed by desalting and concentrating the digestion products in the same well.
authors.affiliation: BD Biosciences, 2 Oak Park, Bedford, MA 01730, USA. Kevin_chen@bd.com
authors.forename: Xiaoxi
authors.initials: X
authors.lastname: Chen
authors.forename: Anthony
authors.initials: A
authors.lastname: Murawski
authors.forename: Guannan
authors.initials: G
authors.lastname: Kuang
authors.forename: Daniel J
authors.initials: DJ
authors.lastname: Sexton
authors.forename: William
authors.initials: W
authors.lastname: Galbraith
mesh_terms: D000818:Animals; D002244:Carbon / Q000737:chemistry; D002417:Cattle; D020724:Elastomers; D006454:Hemoglobins / Q000737:chemistry / Q000378:metabolism; D006801:Humans; D011108:Polymers / Q000737:chemistry*; D012117:Resins, Synthetic / Q000737:chemistry; D012710:Serum Albumin, Bovine / Q000737:chemistry / Q000378:metabolism; D012996:Solutions; D012997:Solvents; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods*; D014357:Trypsin / Q000378:metabolism
chemical_list: D020724:Elastomers; D006454:Hemoglobins; D011108:Polymers; D012117:Resins, Synthetic; D012996:Solutions; D012997:Solvents; C036925:elastomeric polymer; D012710:Serum Albumin, Bovine; D002244:Carbon; D014357:Trypsin