SBIR-STTR Award

High mass molecular ions by electrohydrodynamic emission
Award last edited on: 3/25/02

Sponsored Program
SBIR
Awarding Agency
NIH : NCRR
Total Award Amount
$550,000
Award Phase
2
Solicitation Topic Code
-----

Principal Investigator
John F Mahoney

Company Information

Phrasor Scientific Inc

1536 Highland Avenue
Duarte, CA 91010
   (626) 357-3201
   N/A
   N/A
Location: Single
Congr. District: 32
County: Los Angeles

Phase I

Contract Number: 1R43RR003675-01
Start Date: 00/00/00    Completed: 00/00/00
Phase I year
1986
Phase I Amount
$50,000
The long-term objective of this research is to develop instrumentation for the mass analysis of proteins and other biological macromolecules in the range of 10,000 to 100,000 AMU. The specific aim of Phase I is to demonstrate the feasibility of producing protein molecular ions generated by ion sources that operate on the principle of electrohydrodynamic (EHD) emission. This alternate ionization method is proposed as a soft ionization method; it reduces the background in spectra introduced by fragment ion species. Glycerol solutions, as opposed to more volatile solvents, will be explored for high mass emission studies. The advantages of glycerol are low vapor pressure, permitting the application of higher electric fields before the onset of breakdown, and high viscosity at low temperatures. Both conditions are highly favorable for enhancing the emission of macromolecular ions. The macromolecular ion emission characteristics will be investigated with respect to solvent flow, ionic strength, and sample concentration. It is anticipated that charged droplet suppression and preferred ion emission will be demonstrated by controlling the solvent throughput and viscosity by cooling the EHD emitter. TOF measurements will be used to measure the particle size distribution of the ion beam.Division of Research Resources (NCRR)

Phase II

Contract Number: 2R44RR003675-02
Start Date: 00/00/00    Completed: 00/00/00
Phase II year
1988
Phase II Amount
$500,000
The long term objective of this application is to develop instrumentation for the mass analysis of biological macromolecules in the mass range 10,00 to 100,000 amu. The specific aim of Phase II is to demonstrate the emission and detection of biological sample ions to MW 11,500 using an electrohydrodynamic (EHD) ionization source mounted on a JEOL double focusing mass spectrometer. The methodology for meeting this goal include a continuation of Phase I studies which examined sample ion desolvation, solvent chemistry and methods for handling small and valuable samples. Enhancement of the intensity of molecular ion emission by cooling the EHD ion source and improved ion transmission by adding beam optics will be pursued. Particular attention will be focused on the demonstrated capability of the EHD ionization process to produce doubly and triply charged ions for extending the detectable mass range of sample ions. Aqueous or high volatility solvents will be explored and characterized for their potential of achieving complete sample desolvation and reducing the complexities in high mass ion spectra observed with glycerol. The commercial application of EHD ion source development, coupled to a matchin mass analyzer, will impact the biotechnology field by introducing a new, more accurate method of high mass molecular weight determinations for proteins and other macromolecular biological compounds.

Thesaurus Terms:
Biomedical Engineering, Instrumentation Not Clinically Oriented Chemistry, Analytical Methods, Ionization Detectors Chemistry, Analytical Methods, Spectrometry, Mass Electricity-Magnetism, Electrical Fields Electroionization (Iontophoretic) Methods, Nontherapeutic Electronic Spectra Ionization Ions Models, Chemical Models, Design And Development Of Models Molecular Weight Molecules, Macromolecules Physical Properties, Evaporation-Condensation Physical Properties, Solvents Proteins Skeletal Movement, Head Movement Temperature, ColdNational Center for Research Resources (NCRR)