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Ioannis A Papayannopoulos

from Ashland, MA
Age ~67

Ioannis Papayannopoulos Phones & Addresses

  • 11 Independence Ln, Ashland, MA 01721 (508) 820-1254 (508) 494-3487
  • 67 Oak Ave, Northborough, MA 01532 (508) 393-7929
  • 451 Concord Rd, Sudbury, MA 01776 (978) 443-2450
  • Chapel Hill, NC
  • Abington, MA
  • Durham, NC

Publications

Us Patents

Matrix With Noise Reduction Additive And Disposable Target Containing The Same

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US Patent:
20050133715, Jun 23, 2005
Filed:
Dec 21, 2004
Appl. No.:
11/019062
Inventors:
Xiangping Zhu - Grafton MA, US
Ioannis Papayannopoulos - Ashland MA, US
Assignee:
Applied Biosystems - Framingham MA
International Classification:
H01J049/00
US Classification:
250288000
Abstract:
A matrix for mass spectrometry, the matrix comprising an additive that minimizes or eliminates adduct formation and/or chemical noise generation is disclosed. Also disclosed is a method for depositing a matrix on a MALDI target plate and a disposable plate having a dissolvable pre-matrix deposited thereon. The matrix material can be 2,5-dimethoxybenzoic acid and a monobasic or dibasic salt or tribasic salt as an adduct-reducing additive, such as ammonium monobasic phosphate and sulfate salts, dibasic citrate salts and tribasic citrate salts.

Identification Of Modified Peptides By Mass Spectrometry

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US Patent:
20050272164, Dec 8, 2005
Filed:
Apr 13, 2005
Appl. No.:
11/104741
Inventors:
Xiangping Zhu - Grafton MA, US
Stephen Hattan - Roslindale MA, US
Xunming Chen - Bedford MA, US
Ioannis Papayannopoulos - Ashland MA, US
Assignee:
Applera Corporation - Framingham MA
MDS Inc. - Concord
International Classification:
G06F019/00
G01N033/48
G01N033/50
US Classification:
436086000, 702019000
Abstract:
In various aspects, provided are methods for identification of the presence of modified peptides using at least in part mass spectrometric signals from metastable ions that are formed in the field free region of the analyzer. For example, in various embodiments where the modified peptides are phosphopeptides, such metastable ions can appear approximately 95 u lower than the precursor ion m/z value from which they were formed when the peptide contains a phosphate group. In various embodiments, detection of such metastable ions in a MALDI-TOF mass spectrum can identify the modified peptide. In various aspects, provided are methods for identification of the presence of modified peptides using at least in part MS/MS data from two or more of modified peptides, de-modified peptides and non-modified peptides by comparing the sequence and/or site of modification information for two or more of these three forms of a peptide.
Ioannis A Papayannopoulos from Ashland, MA, age ~67 Get Report