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	Characterizing Synthetic Polymers by MALDI MS
		MALDI is a "soft" ionization process that produces (quasi)molecular ions from large nonvolatile molecules, such as proteins, oligonucleotides, polysaccharides, and synthetic polymers, with minimum fragmentation.
		MALDI generates high-mass ions by irradiating a solid mixture of an analyte dissolved in a suitable matrix compound with a pulsed laser beam.
		The concept involves combining MALDI with chromatography: The intensity of the polymer present (the relative abundance of the polymer distribution) is determined by the refractive index response of GPC, and the mass of the eluant is then measured by a mass spectrometer.
	pubs.acs.org /hotartcl/ac/98/jul/report.html (3435 words)

	Matrix-assisted laser desorption/ionization - Wikipedia, the free encyclopedia
		Matrix-assisted laser desorption/ionization (MALDI) is a soft ionization technique used in mass spectrometry, allowing, among other things, the ionization of biomolecules (biopolymers such as proteins, peptides and sugars) which tend to be more fragile and quickly lose structure when ionized by more conventional ionization methods.
		The term matrix-assisted laser desorption ionization (MALDI) was coined in 1985 by Franz Hillenkamp, Michael Karas and their colleagues (Karas et al, 1985).
		In proteomics, MALDI is used for the identification of proteins isolated through gel electrophoresis: SDS-PAGE and two-dimensional gel electrophoresis.
	en.wikipedia.org /wiki/Maldi (1284 words)

	MALDI TOF MS :Instrumentation and tutorials :King's College London
		MALDI was developed for the ionisation of relatively large polypeptides and proteins but its application has widened to incorporate glycoproteins, oligonucleotides and complex carbohydrates.
		MALDI TOF MS analysis is sensitive and very rapid as once the sample has been mixed with a 'matrix' on a MALDI target, a spectrum can be generated within seconds.
		MALDI MS was introduced in the late 80s when it was demonstrated that adding a small molecular weight organic matrix to an analyte could overcome molecular photodissociation of the sample ions induced by direct laser irradiation.
	www.kcl.ac.uk /schools/health/resfac/mspec/instr/maldi-tof-intro.html (1245 words)

	Mauritz - MALDI-TOF Mass Spectrometry
		MALDI is a ‘soft’ ionization technique in which the energy from the laser is spent in volatilizing the matrix rather than in degrading the polymer.
		MALDI studies have been shown to be applicable to polymers of a broad range of chemistry from water-soluble polymers such as poly(ethylene glycol) 12,13,17,18, poly(propylene glycol) 12, poly(styrene sulfonic acid) 14,19, and poly(acrylic acid) 14 to organic-soluble polymers such as poly(styrene) 11,12,17, and poly(butyl methacrylate) 16.
		MALDI samples of the two oligocarbonates, containing the matrix material of dithranol and LiCl and the oligocarbonate were mixed on a molecular level in a THF solvent solution and homogeneously vacuum co-crystallized.
	www.psrc.usm.edu /mauritz/maldi.html (2520 words)

	Maldi Peptide Spectra
		To interpret a MALDI spectrum de novo, all we can do is to regard each peak separately, and ask 'what peptides could have given rise to this peak?' We know that the mass of a peptide is the sum of the amino acids which comprise it, as listed in table 4.
		Given a mass read from a MALDI peak, and a protein library, it is easy to write a computer algorithm to 'walk' through the library, identifying sequences of amino acids in the library that could give rise to that mass.
		If we find our MALDI spectrum gives hits on two similar proteins, it may be hard to tell whether what we have is a genuine hit together with another similar protein, or a genuine hit together with an erroneous version of the same protein.
	www.weddslist.com /ms/maldi.html (5388 words)

	MALDI (Site not responding. Last check: )
		MALDI is an acronym for matrix assisted laser desorption ionization.
		A sample submitted for MALDI will give the best results if it is clean from all salts, detergents, and acids with the exception of acetic, formic and triflouroacetic acids.
		Although best results are obtained in the absence of salts, MALDI is the least sensitive of all the ionization techniques to ion suppression caused by impurities and mixtures.
	www.uga.edu /mass-spec/guide/MALDI.html (361 words)

	MALDI MS
		MALDI mass spectra of melittin in CHCA comparing mass resolution obtained in the linear mode utilizing continuous ion extraction (upper) and delayed ion extraction (lower) at threshold laser irradiance.
		Many variables influence the integrity of a good, homogeneous MALDI sample and may include the concentration of the matrix and analyte, choice of matrix, analyte sample history (i.e.,exposure to strong ionic detergents, formic acid), hydrophobicity or hydrophilicity character, contaminants and compatible solubilities of matrix and analyte solutions, just to mention a few.
		MALDI fast metastable ion decay is observed for the oxidized B chain of bovine insulin (3495.94 Da) in DHB (Figure 7).
	www.abrf.org /ABRFNews/1997/June1997/jun97lennon.html (3622 words)

	Infrared MALDI - Murray Mass Spectrometry Group (Site not responding. Last check: )
		MALDI mass spectrometry is usually performed using a pulsed ultraviolet laser, typically a small nitrogen laser at 337 nm.
		MALDI using two UV laser pulses has been performed in the UV using a single laser and optical delay line or two lasers of the same wavelength (Moskovets and Vertes, 2002; and references therein).
		The MALDI mass spectrum at the top was obtained using a succinic acid matrix in a matrix to analyte molar ratio of 1000.
	ch309c.chem.lsu.edu:16080 /wiki/index.php/Infrared_MALDI (1783 words)

	UIUC Mass Spec Lab: Ionization Techniques: MALDI
		MALDI is an ionization technique for large and/or labile molecules such as peptides, proteins, polymers, dendrimers, and fullerenes.
		MALDI produces both positive and negative ions, usually in the forms of (M+H)+, (M+Na)+ and (M-H)-.
		MALDI is useful for mixtures such as tryptic digests since the technique produces predominantly (M+H)+ species for lower molecular weight compounds.
	www.scs.uiuc.edu /~msweb/ion.maldi.html (261 words)

	ARS \| Publication request: IMPROVED TECHNIQUE FOR ROBOTIC SPOTTING AND DETECTION OF LOW ABUNDANCE PROTEINS BY ...
		In this study, the effect of matrix concentration, spotting sequence (sample over matrix or vise versa), and sample stage heating were evaluated to maximize peptide detection and identification.
		Trypsin digested peptide mixtures or standard solutions of des-Arg(1)-bradikinin; angiotensin I, and Glu(1) fibrinopeptide B in the concentration range of 1-50 fmols in acetonitrile:H2O (70:30) were spotted onto MALDI plates using CHCA as matrix in the concentration range between 0.3 to 5 mg/ml in acetonitrile:H2O (50:50).
		The MALDI plate was at room temperature or preheated at 50 degrees C and spotted separately with matrix and peptides as follows: matrix first and then peptides, peptides first and then matrix, manually or using a PerkinElmer MultiProbe II EX robot fitted with a custom plate heater.
	www.ars.usda.gov /research/publications/publications.htm?SEQ_NO_115=176792 (470 words)

	MALDI Microfluidics - Murray Mass Spectrometry Group
		The interface allows for the ball, held at a high voltage, to simultaneously accelerate MALDI ions and be used as an electrode for electrophoresis.
		Standard crystalline MALDI matrices are used with a 355 nm Nd:YAG laser for desorption.
		The off-line part of the MALDI microfluidics project is centered on matrix-free soft laser desorption ionization from capillary gel microfluidic chips.
	ch309c.chem.lsu.edu:16080 /wiki/index.php/MALDI_Microfluidics (850 words)

	MALDI Mass
		It is believed that compounds with labile protons, such as carboxylic acids, are good MALDI matrices in the positive ion mode because they are easily able to protonate neutral analyte molecules in the plume.
		The MALDI method has been developed empirically and despite its widespread use, the factors that determine success or failure of MALDI experiments are not yet fully understood.
		In its current state, MALDI is primarily based on the laser desorption of solid matrix-analyte deposits [6].
	www.sigmaaldrich.com /Brands/Fluka___Riedel_Home/Bioscience/Peptide_Analysis/MALDI_Mass.html (767 words)

	MALDI Mass Analysis
		MALDI offers a quick and easy method of mass analysis using a minimal amount of sample.
		MALDI has also been used as a method of N-terminal and C-terminal protein/peptide sequencing.
		MALDI samples should be free of SDS, and should not be radioactive.
	www.biotech.iastate.edu /facilities/protein/maldi.html (696 words)

	MALDI of Synthetic Polymers
		Since the first reports of the application of MALDI for synthetic polymer analysis [1-2], significant advances in sample preparation protocols and instrumentation development have been taken place.
		Thus, they are the most difficult to analyze by MALDI because a homogeneous mixture of matrix and analyte is not easily obtained.
		Overall, the development of MALDI in the analysis of industrial polymers is still in the early stage.
	www.chemistry.wustl.edu /~msf/damon/synthetic_polymers.html (916 words)

	MALDI-TOF Mass Spectrometry
		Careful sample preparation is essential for obtaining reliable MALDI data, and individual users will be responsible for this.
		The MALDI is suitable for walk-up use, but as with any sophisticated instrument, prior preliminary training in its operation is essential.
		MALDI users are charged based on either usage time or per experiment.
	wings.buffalo.edu /smbs/bch/researchfacil/maldi.htm (447 words)

	MALDI
		An unexpected side effect of the matrix was that it allowed for the laser incidence spot to be refreshed between each pulse, thus greatly enhancing shot-to-shot reproducibility.
		This was the foundation of matrix-assisted laser desorption/ionisation (MALDI).
		Later developments by Koichi Tanaka [3] demonstrated the application of MALDI to a whole range of biological macromolecules.
	www.chm.bris.ac.uk /ms/theory/maldi-ionisation.html (633 words)

	UCDHSC Clinical Nutrition Research Lab - Maldi Ms And AP-MALDI Ms/Ms
		UCDHSC Clinical Nutrition Research Lab - Maldi Ms And AP-MALDI Ms/Ms If all you see are spots you need to have the CNRU Mass Spectrometry Core do your advanced research for you.
		MALDI MS AND AP-MALDI MS/MS Matrix-Assisted Laser Desorption Ionization (MALDI) is a method used to generate gas phase ions from peptide mixtures.
		The gas phase ions are then extracted with a voltage and directed into the mass spectrometer.
	www.uchsc.edu /bioanalytics/services/maldi-ap-maldi.shtml (311 words)

	W.M. Keck Facility at Yale - More Information on Matrix Assisted Laser Desorption Ionization (MALDI) Mass Spectrometry
		Typically, an average 15-mer tryptic peptide might appear in a high resolution MALDI spectrum as a cluster of 4-5 peaks with the first two peaks, which might be approximately equal in size, being the most intense.
		As noted, the MALDI mass spectrum provides an additional criterion to judge peptide purity and the mass of the peptide is often helpful as a further confirmation of the sequence determined by Edman degradation.
		Trypsin digests do not typically require de-salting, so 1.8µl of the digest mixture can be applied directly to the MALDI target after mixing with matrix plus internal standards (i.e., 50 fmol bradykinin and 150 fmol ACTH clip which have protonated monoisotopic masses of 1060.569 and 2465.199 respectively).
	keck.med.yale.edu /prochem/procmald.htm (3471 words)

	BD Biosciences : BD MALDI Sample Concentrator (Site not responding. Last check: )
		BD™ MALDI Sample Concentrator is a silicone elastomer in the format of a 96-well or 100-well plate that fits on top of a typical MALDI plate.
		A 10 nM sample was desalted, concentrated and spotted using the BD™ MALDI Sample Concentrator.
		Figure 3: MALDI MS of a mixture of 5 standard peptides (angiotensin II, synthetic peptide P14R, ACTH fragment 18-39, bovine insulin oxidized B chain, and bovine insulin).
	www.bdbiosciences.com /discovery_labware/products/display_product.php?keyID=241 (609 words)

	Automated MALDI Prep - Biocompare Buyer's Guide
		Description: Tryptic Digest of Gel Spots The digest is carried out in a 96-well PCR plate, which is embedded in an...
		The PROTEINEER fc is a liquid handler for post-column MALDI preparation...
		Description: The TOFprep is a complete high performance MALDI spotting system designed to apply sample and matrix to most...
	www.biocompare.com /matrix.asp?catid=5177 (318 words)

	Other MALDI-TOF protocols
		Use 1μL of the unseparated digests for analysis by MALDI.
		The crushed gel is washed once with an equal volume of fresh extraction solution and the wash is combined with the supernatant.
		An aliquot (1 µl) of the milky supernatant can be immediately retrieved and deposited onto the MALDI probe for MS analysis while the remaining sample is closed and left vortexing for additional extraction.
	www.hmc.psu.edu /core/oldsite/Maldi/othermalditofprotocols.htm (3949 words)

	Mass Spectrometry - Base Peak - The web's leading Mass Spectrometry Resource
		The extracts were spiked with known concentrations of each of the drugs to enable quantification by the standard additions method then mixed with the MALDI matrix solution and spotted onto the target plate.
		However, the MALDI MS/MS method is much faster than the chromatographic methods.
		This increased speed, combined with the smaller sample sizes required and the ability to load many samples onto the target plate at one time suggest that the method is a viable alternative to HPLC-based methods for therapeutic monitoring, although the instrumentation is more expensive.
	www.spectroscopynow.com /coi/cda/detail.cda?chId=4&id=13202&type=Feature&page=1 (711 words)

	Capture and Detection of Bacteria Using Immobilized Antibodies and MALDI-
		Detection of a single bacterial species from environmental samples is often difficult due to the complexity of the sample matrix, the need for concentrated numbers of organisms, and the presence of other bacterial entities.
		The glass plate was then secured to a MALDI probe and subjected to mass analysis.
		After incubation for 1 hour in the bacterial mixture, the glass plates were again vigorously washed and an aliquot of TFA was added to the surface of the plate and allowed to evaporate.
	www.mines.edu /academic/chemistry/research/graduate/ms/capture.htm (1252 words)

	4800 MALDI TOF/TOF Analyzer by Applied Biosystems - New Technologies - Biocompare Buyer's Guide
		The 4800 MALDI TOF/TOF Analyzer utilizes next generation tandem TOF technology that brings together breakthroughs in sensitivity and powerful, easy-to-use workflows.
		The 4800 MALDI TOF/TOF Analyzer provides the smartest, most efficient solution for definitive identification and quantification of proteins for biomarker research.
		The 4800 MALDI TOF/TOF Analyzer is designed for ease-of-use from set-up to data reduction and reporting.
	www.biocompare.com /newtech.asp?id=1598 (184 words)

	MALDI Mass Spectrometry
		The first MALDI experiments were done on proteins.
		I don't know about you, but that MALDI spectrum has always reminded me of the giant fin on the back of a dimetredon, an extinct reptile that lived millions of years ago.
		But MALDI measures the mass more accurately, because it doesn't compare the polymer you're measuring to anything.
	www.pslc.ws /macrog/maldi.htm (1337 words)

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