Rapid subpicogram protein detection on a microchip without denaturing.

Mari Tabuchi; Yasuhiro Kuramitsu; Kazuyuki Nakamura; Yoshinobu Baba

doi:10.1021/pr034009m

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Rapid subpicogram protein detection on a microchip without denaturing.

Mari Tabuchi·Yasuhiro Kuramitsu·Kazuyuki Nakamura·Yoshinobu Baba

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Abstract

Protein size separation based on sodium dodecyl sulfate-gel electrophoresis (SDS-GE) requires denaturing, but we propose that denaturing is unnecessary for analysis by microchip electrophoresis (micro-CE). By omitting the protein denaturing process, we achieved not only shortened total analysis time, but also dramatically improved sensitivity without compromising size determination. The detection limit was improved to 0.1 ng/microL under conditions without denaturing and 600 pg (9.0 femtomol) of bovine serum albumin was detectable, which equals levels detectable by Silver stain, although a routine method by microchips in the Coomassie Blue detection level.

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Databases, Protein Electrophoresis Heat-Shock Proteins Humans Jurkat Cells Mass Spectrometry Microchemistry Protein Denaturation Proteins Proteome Sensitivity and Specificity Comparative Study Journal Article Research Support, Non-U.S. Gov't

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Mari Tabuchi, Yasuhiro Kuramitsu, Kazuyuki Nakamura, Yoshinobu Baba. Rapid subpicogram protein detection on a microchip without denaturing.. https://doi.org/10.1021/pr034009m

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