What can MALDI-TOF identify?
A number of researchers have shown that MALDI-TOF MS can be used for early identification of bacteria in blood cultures, urinary tract infections (UTIs), cerebrospinal fluids, respiratory tract infections, stool samples etc.
How does MALDI-TOF mass spectrometry work?
In the case of MALDI-TOF, the analyzer separates molecules based on the time it takes each of them to fly through the time-of-flight tube or “drift” region to the detector. The ionized sample molecules are accelerated by a high-voltage current and fly through the tube before striking the detector.
What is TOF mass spectrometry used for?
A common form of mass spectrometry is time of flight (ToF) mass spectrometry. In this technique, particles of the substance are ionised to form 1+ ions which are accelerated so that they all have the same kinetic energy. The time taken to travel a fixed distance is then used to find the mass of each ion in the sample.
What are some applications in the Clinical Laboratory of Mass Spectrometry MALDI-TOF MS?
The MALDI-TOF MS system is increasingly used in clinical diagnostic laboratory for viral identification, mutation analysis, genotyping, and antiviral resistance studies.
What is the principle of MALDI-TOF?
MALDI is the abbreviation for “Matrix Assisted Laser Desorption/Ionization.” The sample for MALDI is uniformly mixed in a large quantity of matrix. The matrix absorbs the ultraviolet light (nitrogen laser light, wavelength 337 nm) and converts it to heat energy.
What types of sample are suitable for MALDI-TOF mass analysis?
Samples for MALDI analysis may be supplied either in solution or lyophilised. Ideally samples should be resuspended in an aqueous solution of 50% (v/v) acetonitrile, 0.1% (v/v) trifluoroacetic acid using ultra high purity water. If any other solution is used, BioCentre staff must be supplied with comprehensive details.
What is the function of MALDI-TOF in determining the protein composition and structure?
The MALDI-TOF can be used in profiling and imaging proteins directly from thin tissue sections, known as MALDI imaging mass spectrometry (MALDI-IMS). It provides specific information about the local molecular composition, relative abundance and spatial distribution of peptides and proteins in the analyzed section.
How does a TOF MS work?
Time-of-flight mass spectrometry (TOFMS) is a method of mass spectrometry in which an ion’s mass-to-charge ratio is determined by a time of flight measurement. Ions are accelerated by an electric field of known strength. From this ratio and known experimental parameters, one can identify the ion.
How does a TOF mass analyzer work?
The principle of ToF mass analyzer involves the separation of ions based on the time it takes for the ions to travel through a flight tube with known length and reach the detector.
What is principal operation of TOF mass spectrometer?
What is TOF analysis?
Time-of-Flight Secondary Ion Mass Spectrometry (ToF-SIMS) is a surface-sensitive analytical method that uses a pulsed ion beam (Cs or microfocused Ga) to remove molecules from the very outermost surface of the sample. The particles are removed from atomic monolayers on the surface (secondary ions).
What is the principle of Maldi-Tof?
What are the stages of a TOF mass spectrometer?
TOF mass spectrometers are therefore smaller and lighter than the traditional machines. In both types of mass spectrometer, there are three stages involved in the analysis of a sample: 1. Ionisation. 2. Separation of charged species. 3. Detection.
When was time of flight mass spectrometry developed?
Time-of-flight mass spectrometry (TOF MS) was developed in the late 1940’s, but until the 1990’s its popularity was limited. Recent improvements in TOF technology, including orthogonal acceleration, ion mirrors (reflectron), and high-speed electron- ics, have significantly improved TOF resolution.
What is the repetition rate of a TOF mass analyzer?
Commercial orthogonal acceleration TOF mass analyzers typically operate at 5–20 kHz repetition rates. In combined mass spectra obtained by summing a large number of individual ion detection events, each peak is a histogram obtained by adding up counts in each individual bin.
What kind of mass spectrometry is used for tandem time of flight?
Tandem time-of-flight ( TOF/TOF) is a tandem mass spectrometry method where two time-of-flight mass spectrometers are used consecutively. To record full spectrum of precursor (parent) ions TOF/TOF operates in MS mode.