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  • visualizing analyte
  • A water cooled Peltier thermoelectric plate is used to control the sample temperature (−10 °C to 80 °C). The IR-MALDESI source is currently used to investigate the fundamentals of the ionization process, in addition to being routinely employed for visualizing analyte distributions in biological, forensic, and pharmaceutical samples. (wikipedia.org)
  • droplets
  • Sample preparation was optimized and included mechanical disruption followed by the application as dried droplets with the matrices α-cyano-4-phenylcinnamic acid and sinapinic acid as well as ethanol. (rsc.org)
  • The matrix is sprayed, as very small droplets, onto the surface of the sample, allowed to dry, and re-coated until there is enough matrix to analyze the sample. (wikipedia.org)
  • DESI
  • Both DESI and direct analysis in real time (DART) have been largely responsible for the rapid growth in ambient ionization techniques, with a proliferation of more than thirty new techniques being found today. (wikipedia.org)
  • The combination of these two advancements led to the introduction of DESI and DART as the main ambient ionization techniques that would later become multiple different techniques. (wikipedia.org)
  • DESI is a technique that allows for ambient ionization of a trace sample at atmospheric pressure, with little sample preparation. (wikipedia.org)
  • Suitable
  • First, the sample is mixed with a suitable matrix material and applied to a metal plate. (wikipedia.org)
  • Scientists take thin tissue slices mounted on conductive microscope slides and apply a suitable MALDI matrix to the tissue, either manually or automatically. (wikipedia.org)
  • chromatography
  • In contrast to the traditional MS methods, where the dye must be extracted from the fabric and the dye components are separated by chromatography prior to mass spectrometric analysis, the IR-MALDESI source allows for direct analysis of the dye from the fabric. (wikipedia.org)
  • 1991
  • Michael Barber (3 November 1934 - 8 May 1991) was a British chemist and mass spectrometrist best known for his invention of fast atom bombardment ionization. (wikipedia.org)
  • crystals
  • Sublimation can also be used to make uniform matrix coatings with very small crystals. (wikipedia.org)
  • Controlling the heating time controls the thickness of the matrix on the sample and the size of the crystals formed. (wikipedia.org)
  • sinapinic acid
  • Further improvements were realized through the use of a 355 nm laser and the cinnamic acid derivatives ferulic acid, caffeic acid and sinapinic acid as the matrix. (wikipedia.org)
  • A good example of a matrix-solution would be 20 mg/mL sinapinic acid in ACN:water:TFA (50:50:0.1). (wikipedia.org)
  • wavelength
  • The availability of small and relatively inexpensive nitrogen lasers operating at 337 nm wavelength and the first commercial instruments introduced in the early 1990s brought MALDI to an increasing number of researchers. (wikipedia.org)
  • The matrix must absorb at the laser wavelength and ionize the analyte. (wikipedia.org)
  • samples
  • Samples could be desorbed from the surface without using matrices. (wikipedia.org)
  • introduced by the group of Renato Zenobi in 2010, is an analytical platform for high-throughput analysis of single cells and other low-volume samples by mass spectrometry. (wikipedia.org)
  • Coupled Ionization sources-MS systems are popular in the chemical analysis because the individual capabilities of various sources combined with different MS systems allow for chemical determinations of samples. (wikipedia.org)
  • Analysis
  • Volmer, D.A., Mendes, L.R.B.C., Stokes, C.S.: Analysis of vitamin D metabolic markers by mass spectrometry: current techniques, limitations of the "gold standard" method, and anticipated future directions. (springer.com)
  • Kevin Downard is an Australian academic scientist whose research specialises in the field of mass spectrometry as it applies to molecular analysis in the life and medical sciences. (wikipedia.org)
  • Digital microfluidics can be used together with analytical analysis procedures such as mass spectrometry, colorimetry, electrochemical, and electrochemiluminescense. (wikipedia.org)
  • tissue
  • With the operation of a variety of tissue-cutting tools, such as a diathermy knife, a surgical laser, or an ultrasonic tissue atomizer, an aerosol is formed having a composition characteristic of the tissue cut, which also contains ionized cell constructs. (wikipedia.org)
  • Among them, in terms of using the REIMS method, the intact membrane-forming phospholipids are important, which easily are detectable by mass spectrometry on the one hand, and on the other hand, contain the combination of the characteristics of the particular tissue type. (wikipedia.org)
  • MALDI imaging mass spectrometry (MALDI-IMS) is the use of matrix-assisted laser desorption ionization as a mass spectrometry imaging technique in which the sample, often a thin tissue section, is moved in two dimensions while the mass spectrum is recorded. (wikipedia.org)
  • The matrix is placed in a sublimation chamber with the mounted tissue sample inverted above it. (wikipedia.org)
  • Histology Tissue microarray Laser capture microdissection Powers, Thomas W. (wikipedia.org)
  • absorb
  • They have a strong optical absorption in either the UV or IR range, so that they rapidly and efficiently absorb the laser irradiation. (wikipedia.org)
  • uses
  • The more recent MALDESI source uses a thin layer of ice as the energy-absorbing matrix that is resonantly excited using a mid-infrared (IR) laser. (wikipedia.org)
  • source
  • The source has single- or multi-shot capabilities with adjustable laser fluence, repetition rate, as well as the delay between the laser trigger and MS ion accumulation. (wikipedia.org)
  • study
  • He has developed mass spectrometry approaches to type, subtype, study the lineage, antigenicity, and evolution of the influenza virus and other biopathogens, and has investigated the molecular basis of new antiviral enzyme inhibitors, to help arrest the impact of infectious diseases on human health. (wikipedia.org)
  • ablates
  • The oven temperature is approximately 1200 °C. As the laser ablates the target, carbon nanotubes form and are carried by the gas flow onto a cool copper collector. (wikipedia.org)
  • spectroscopy
  • The field has gained momentum with the advent of technology where different techniques such as X-ray, NMR, mass spectroscopy, HPLC and two-dimensional PAGE have resulted in the generation of enormous experimental data. (springer.com)
  • analyte
  • Dilute the analyte solution in matrix solution to a final analyte concentration between 0.2 and 2µM. (rockefeller.edu)
  • This precipitate is the cocrystallization of matrix and analyte. (rockefeller.edu)
  • In Matrix-assisted inlet ionization (MAII), a matrix which can be a solvent is used at ambient temperature with the analyte of interest as a mixture. (wikipedia.org)
  • The matrix/analyte mixture is inserted into the heated inlet tube through tapping the mixture at the opening end of the tube. (wikipedia.org)
  • For this ionization pathway, the gas-phase acidity of the protonated water clusters and the gas-phase basicity of the analyte molecule are of crucial importance. (wikipedia.org)
  • Nevertheless, these ionization mechanisms may also lead to the formation of adducts and oxidation of the original analyte compounds. (wikipedia.org)
  • Matrix selection and solvent system relies heavily upon the analyte class desired in imaging. (wikipedia.org)
  • The analyte must be soluble in the solvent in order to mix and recrystallize the matrix. (wikipedia.org)
  • quadrupole
  • citation needed] The quadrupole mass analyzer (a radio frequency quadrupole used as a mass filter) was invented by Wolfgang Paul in the late 1950s to early 60s at the University of Bonn, Germany. (wikipedia.org)
  • atomic
  • Despite its long history, high-sensitivity high-accuracy mass measurements of atomic nuclei continue to be very important areas of research for many branches of physics. (wikipedia.org)
  • Heat
  • Heat is applied to the matrix, causing it to sublime and condense onto the surface of the sample. (wikipedia.org)
  • Very short laser pulses remove material so quickly that the surrounding material absorbs very little heat, so laser drilling can be done on delicate or heat-sensitive materials, including tooth enamel (laser dentistry). (wikipedia.org)
  • sample
  • For example, start with 1µl of sample and 9µl of matrix solution. (rockefeller.edu)
  • Spot 0.5µl of sample/matrix mixture on the plate. (rockefeller.edu)
  • The matrix is sprayed, as very small droplets, onto the surface of the sample, allowed to dry, and re-coated until there is enough matrix to analyze the sample. (wikipedia.org)
  • The matrix is placed in a sublimation chamber with the mounted tissue sample inverted above it. (wikipedia.org)
  • Controlling the heating time controls the thickness of the matrix on the sample and the size of the crystals formed. (wikipedia.org)
  • coatings
  • Also, laser energy can be selectively absorbed by coatings, particularly on metal, so CO2 or Nd:YAG pulsed lasers can be used to clean surfaces, remove paint or coating, or prepare surfaces for painting without damaging the underlying surface. (wikipedia.org)
  • this is a special type of physical vapor deposition called pulsed laser deposition (PLD), and can create coatings from materials that cannot readily be evaporated any other way. (wikipedia.org)
  • results
  • The results of mass spectrometry indicated that the 25-kDa band corresponded to the hypothetical cytochrome c subunit encoded by the ORF APE_1719.1 . (beds.ac.uk)
  • In LSII the use of the laser increases the image quality of the results by producing better spatial resolution. (wikipedia.org)