title: Measuring masses of single bacterial whole cells with a quadrupole ion trap.
abstract: A novel method has been developed to precisely measure the masses of single bacterial whole cells using a quadrupole ion trap as an electrodynamic balance. The bacterial cells were introduced into the ion trap by matrix-assisted laser desorption/ionization, confined in space by audio frequency ac fields, and detected by elastic light scattering. Mass measurement accuracy approaching 0.1% was achieved for Escherichia coli K-12 with a mass distribution of +/-3% from 60 repetitive measurements of the particles and their clusters. This is the first high-precision mass measurement reported for any intact microorganisms with masses greater than 1 x 1010 Da. The method opens new avenues for high-precision mass measurement of single microbial particles and offers an alternative approach for rapid identification of microorganisms by mass spectrometry.
authors.affiliation: Institute of Atomic and Molecular Sciences, Academia Sinica, P.O. Box 23-116, Taipei, Taiwan 106, ROC.
authors.forename: Wen-Ping
authors.initials: WP
authors.lastname: Peng
authors.forename: Yi-Chang
authors.initials: YC
authors.lastname: Yang
authors.forename: Ming-Wei
authors.initials: MW
authors.lastname: Kang
authors.forename: Yuan T
authors.initials: YT
authors.lastname: Lee
authors.forename: Huan-Cheng
authors.initials: HC
authors.lastname: Chang
mesh_terms: D004548:Elasticity; D048168:Escherichia coli K12 / Q000737:chemistry* / Q000254:growth & development; D008027:Light; D012542:Scattering, Radiation; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods*