Ultrathin calcinated films on a gold surface for highly effective laser desorption/ ionization of biomolecules

Patent metadata

Field	Value
Publication number	US-2016202266-A1
Application number	US-201514934755-A
Country	US
Kind code	A1
Filing date	Nov 6, 2015
Priority date	May 18, 2010
Publication date	Jul 14, 2016
Grant date	—

Abstract

A nanoscale calcinated silicate film fabricated on a gold substrate for highly effective, matrix-free laser desorption ionization mass spectrometry (LDI-MS) analysis of biomolecules. The calcinated film is prepared by a layer-by-layer (LbL) deposition/calcination process wherein the thickness of the silicate layer and its surface properties are precisely controlled. The film exhibits outstanding efficiency in LDI-MS with extremely low background noise in the low-mass region, allowing for effective analysis of low mass weight samples and detection of large biomolecules including amino acids, peptides and proteins. Additional advantages for the calcinated film include ease of preparation and modification, high reproducibility, low cost and excellent reusability. Experimental parameters that influence LDI on calcinated films have been systemically investigated. Presence of citric acid in the sample significantly enhances LDI performance by facilitating protonation of the analyte and reducing fragmentation. The wetting property and surface roughness appear to be important factors that manipulate LDI performance of the analytes. This new substrate presents a marked advance in the development of matrix-free mass spectrometric methods and is uniquely suited for analysis of biomolecules over a broad mass range with high sensitivity.

First claim

1 . A nanoscale film, comprising:
a sublayer; and a nanoscale metallic layer with low heat conductivity on the sublayer.

2 .- 12 . (canceled)

13 . A calcinated silicate film, comprising:
a layer by layer deposition of poly(allylamine hydrochloride) PAH and sodium silicate (water glass) on a gold surface.

14 . A method of forming a calcinated silicate film comprising:
placing a sublayer onto a stainless steel tape and/or glass slide; alternately depositing poly(allylamine hydrochloride) PAH and a sodium silicate solution onto a surface of the sublayer; and calcinating the alternately deposited layers of PAH and sodium silicate solution.

15 .- 34 . (canceled)

Assignees

• Univ California

Inventors

• Cheng Quan
• Duan Jicheng
• Linman Matthew James

Classifications

• C23C18/143

  Radiation by light, e.g. photolysis or pyrolysis · CPC title

• Y10T428/265

  1 mil or less · CPC title

• C23C18/165

  Multilayered product (layered product B32B) · CPC title

• C23C18/1212 Primary

  Zeolites, glasses · CPC title

• C23C18/1241

  Metallic substrates · CPC title