Matrix- and substrate-assisted laser desorption for fast DNA sequencing
Tremendous effort has been put to achieving fast sequencing of DNA due to the potential great applications in biological and medical research. Current DNA sequencing methods were developed by Sanger and Maxam-Gilbert. Both radioactive methods and fluorescent dye labeling methods for DNA sequencing require the use of the time-consuming gel electrophoresis method. It is desirable to consider a time-of-flight mass spectrometer approach to DNA sequencing since the time needed for separation of DNA segments in a mass spectrometer is a few microseconds instead of a few hours in gel electrophoresis. However, there are two major difficulties: developing a reliable method to deliver these nonvolatile biopolymers to the mass spectrometer`s ionization zone, and achieving ion production without significant fragmentation in either the desorption or ionization steps. Electrospray and laser-desorption ionization have been considered to have good potential for overcoming these difficulties. Large polypeptide molecules can be put into the gas phase and ionized by a laser in the presence of excessive amounts of nicotinic acid molecules serving as a matrix, a method called the matrix-assisted laser desorption/ionization (MALDI). Matrix-assisted UV desorption and ionization has also been applied to DNA segments; however, the success has been limited to very small segments. MALDI has been used here for detecting medium sizes of oligomers. Fast sequencing of DNA by laser mass spectrometry can possibly be achieved by discovering new matrices for efficient production of parent ions of large oligomers. Another approach is to achieve efficient post-ionization after the desorption. The first step has been taken, the success may not be very far away.
- Research Organization:
- Oak Ridge National Lab., TN (United States)
- Sponsoring Organization:
- USDOE, Washington, DC (United States)
- DOE Contract Number:
- AC05-84OR21400
- OSTI ID:
- 10163898
- Report Number(s):
- CONF-930159-37; ON: DE93015332
- Resource Relation:
- Conference: OE/LASE `93: International Society for Optical Engineering (SPIE) conference,Los Angeles, CA (United States),13-23 Jan 1993; Other Information: PBD: [1993]
- Country of Publication:
- United States
- Language:
- English
Similar Records
Laser desorption mass spectrometry for DNA analysis and sequencing
Laser desorption mass spectrometry for fast DNA analysis