EP0434792A1 - Ions a charge multiple et procede de determination du poids moleculaire de grandes molecules - Google Patents

Ions a charge multiple et procede de determination du poids moleculaire de grandes molecules

Info

Publication number
EP0434792A1
EP0434792A1 EP90909301A EP90909301A EP0434792A1 EP 0434792 A1 EP0434792 A1 EP 0434792A1 EP 90909301 A EP90909301 A EP 90909301A EP 90909301 A EP90909301 A EP 90909301A EP 0434792 A1 EP0434792 A1 EP 0434792A1
Authority
EP
European Patent Office
Prior art keywords
ions
mass
droplets
solution
composition
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP90909301A
Other languages
German (de)
English (en)
Other versions
EP0434792A4 (en
Inventor
John B. Fenn
Chin Kai Meng
Matthias Mann
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Individual
Original Assignee
Individual
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Individual filed Critical Individual
Publication of EP0434792A1 publication Critical patent/EP0434792A1/fr
Publication of EP0434792A4 publication Critical patent/EP0434792A4/en
Withdrawn legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J49/00—Particle spectrometers or separator tubes
    • H01J49/26—Mass spectrometers or separator tubes
    • H01J49/34—Dynamic spectrometers
    • H01J49/42—Stability-of-path spectrometers, e.g. monopole, quadrupole, multipole, farvitrons
    • H01J49/426—Methods for controlling ions
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D59/00—Separation of different isotopes of the same chemical element
    • B01D59/44—Separation by mass spectrography
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J49/00—Particle spectrometers or separator tubes
    • H01J49/02—Details
    • H01J49/10—Ion sources; Ion guns
    • H01J49/16—Ion sources; Ion guns using surface ionisation, e.g. field-, thermionic- or photo-emission
    • H01J49/165—Electrospray ionisation

Definitions

  • This invention relates to improvements in a method for mass spectrometric analysis of chemical compounds in solution.
  • it is concerned with determining the mass or molecular weight of large fragile solute species with greater speed, convenience and accuracy than has been possible by previous methods.
  • the invention also relates to new compositions of matter comprising populations of ions having a multiplicity of charges.
  • Mass spectrometry consists in "weighing" individual molecules by transforming them intact into ions in vacuo and then measuring the response of their trajectories to various combinations of electric and/or magnetic fields. Attempts to extend the application of mass spectrometric methods to the analysis of very large polar organic and bio-organic molecules have long been frustrated by the difficulties of transforming such molecules into ions. The analytical advantages of mass spectrometry for such parameters as detection sensitivity, accuracy of mass measurement and abundance determinations cannot be realized if the prerequisite ions cannot be formed. Large polar molecules generally cannot be vaporized, even in vacuo, without extensive, even catastophic, decomposition.
  • Plasma Desorption in which disintegration of a radioactive isotope, usually Californium-252, produces a small blob of plasma on the surface from which a few intact ions of analyte emerge
  • SIMS Secondary Ionization Mass Spectrometry
  • FIB Fast Ion Bombardment
  • Electrohydrodynamic Ionization analyte is dissolved in a non-volatile liquid (e.g. glycerol) and injected into an evacuated chamber through a small capillary tube maintained at high voltage.
  • the solvent liquid must have a low vapor pressure so that it won't "freeze-dry” from rapid evaporation into vacuum.
  • Solute ions along with molecules and clusters of solvent, are desorbed from the emerging liquid by the high field at its surface and can be mass analyzed.
  • EH has not been widely practiced, in part because few liquids that have low vapor pressure are good solvents for large polar bio-organic compounds, in part because the desorbed ions are usually solvated with one or more molecules of the solvent, and in part because they often have a wide distribution of energies.
  • the product ions have high energies and require magnetic sector analyzers.
  • the charging is a result of statistical fluctuations in the distribution of cations and anions as the liquid is nebulized.
  • APIE Atmospheric Pressure Ion Evaporation
  • J.V. Iribarne and B.A. Thomson droplets are produced by intersecting a flow of sample solution with a high speed jet of air.
  • APIE will be referred to by the more convenient term Aerospray (AS) to indicate that it is based on pneumatic nebulization of the sample liquid.
  • Electrospray (ES) ionization which can be considered a sort of mirror image of TS and AS in that instead of producing charging by atomization it produces atomization by charging.
  • ES Electrospray
  • the liquid sample is introduced through a small bore tube maintained at several kilovolts with respect to the surrounding walls of a chamber containing bath gas, usually but not necessarily at or near atmospheric pressure.
  • the electrostatic field at the tip of the tube charges the surface of the emerging liquid.
  • the resulting coulomb forces overcome the liquid's surface tension and disperse it into a fine spray of charged droplets.
  • the nebulization is by electrostatic forces that provide a much higher charge/mass ratio for the resulting droplets that can be achieved in TS and AS. If the field at the tip of the tube is too high, or the pressure of the ambient bath gas is too low, a corona discharge will occur at the tip of the tube and substantially decrease the effectiveness of the nebulization.
  • This ES ionization technique is fully described in U.S. Patents 4,531,056 and 4,542,293 which were granted in 1985.
  • an ES source can produce ions from very large and complex solute species without any fragmentation. These species are so involatile that they could not possibly be converted intact into ions by ionization techniques such as El, PI, CI or Al. Nor have there been reports that such large species have been ionized by either TS or AS. Moreover, and unexpectedly, it turns out that for species of large molecular weight the resulting ions each contain a large number of charges, distributed between a minimum and maximum number. The values of these minimum and maximum numbers depend on the size and composition of the species. For example, from protein solutes with molecular weights up to nearly 40,000 ions with up to 40 or more charges have been obtained.
  • an important feature of this invention was the discovery that with an ES ion source one could obtain useful mass spectra containing peaks corresponding to intact parent molecules, even though the molecular weight of those molecules was much higher than the nominal upper mass limit of the analyzer used to obtain the spectra. This remarkable result was entirely unexpected and had never been anticipated before this invention was reduced to practice.
  • Multiply charged ions have also been produced by these methods from other large and complex molecules such as sugars, polynucleotides and synthetic polymers.
  • Covey, et al. obtained a mass spectrum with 6 peaks for parent ions containing from 6 to 11 negative charges.
  • T.R. Covey, R.F. Bonner, B.I. Shushan and J.D. Henion, Rapid. Commun. Mass Spectrom. 2, 249 (1988) A key requirement is that molecules that are not themselves ions contain polar atoms or groups, e.g.
  • ions comprising individual molecules with such high degrees of multiple charging are new to the laboratory.
  • the classical ionization methods based on gas phase encounters between volatile molecules and electrons, photons or other ions, usually produce only singly charged ions but sometimes have provided ions with two charges and on rare occasions with three. Ions containing multiple charges have been produced by some of the recently developed "soft" ionization methods mentioned earlier such as TS, AS, FAB, SIMS and PD but usually with only two or three charges, never more than five or six.
  • a substantial fraction of the ions produced by these methods are singly charged, even for the very largest species.
  • the total translational energies (more properly "enthalpies") of the ions after expansion are higher than their thermal energies at the source temperature by a factor that is approximately equal to the ratio of the molecular weight of the ion to the mean molecular weight of the source gas, i.e. the concentration weighted average of the heavy species (ions) and the light species (bath gas) .
  • ions with a molecular weight of 100,000 at very low concentration in a bath gas of nitrogen expanded from a source temperature of 350K could in principle be accelerated to a translational kinetic energy of about 370 eV.
  • a further advantage of this invention stems from a surprising finding in the ES ionization of large solute species that are pure compounds.
  • the spectrum resulting from mass analysis of ions from an ES source comprises a sequence of peaks whose ions are multiply charged and differ from those of adjacent peaks by a single charge.
  • PEGs poly ethylene glycols
  • our invention relates to the production of mass spectra comprising a multiplicity of peaks, these peaks being produced by multiple charging of species with a relatively high molecular weight. It further relates to methods for the recovery of information from such spectra.
  • An additional feature of the invention relates to the nature of the populations of multiply charged ions that we have been able to produce. They represent a new composition of matter.
  • FIG. 1 is a simplified schematic representation of an apparatus with which the invention can be practiced.
  • FIG. 2 displays mass spectra obtained for eight proteins with an apparatus that embodies the essential features schematically portrayed in Fig 1. The number i of charges per constituent ion is indicated for representative peaks.
  • FIG. 3 shows a consistency check for the various peaks in the spectrum of the protein cyctochrome C shown in Fig. 2.
  • the solid line is plot of Equation 5.
  • the points are ratios of measured m/z values for different pairs of peaks (K'i/K'i+j), each for a different pair of peaks.
  • the peak positions are as measured in the spectrum from Fig. 1.
  • (b) same as (a) except that the peak for i 14 has been deliberately offset by 5 units on the m/z scale.
  • the points representing peak ratios involving the offset peak are crosses.
  • the dashed line shows the effect on the unweighted average mass, the solid line on the weighted mass. Note that the weighted average is much less affected by the offset peak once that peak is away from its "best position" with respect to the rest of the peaks in the sequence.
  • FIG. 5 (a) A synthetic sequence of peaks for ions with from 6 to 15 charges, (b) Deconvolution of (a) by Equation 8. The mass scale is in units of the parent mass M.
  • FIG. 9 Electrospray mass spectrum for a mixture of cytochrome C and myoglobin along with the deconvoluted spectrum for each species obtained by application of Equation 8.
  • FIG. 1 shows a schematic representation of an apparatus in our laboratory that embodies the essential features of Electrospray Mass Spectrometry (ESMS) and has been described elsewhere.
  • ESMS Electrospray Mass Spectrometry
  • the most direct way to achieve this potential difference is to float the source of sample liquid, the hypodermic injection needle and the tube connecting them, at the required voltage while the rest of the apparatus is at or near ground potential. It is also possible to maintain the liquid injection needle at the required high potential, leaving the source of liquid sample at ground potential so that there is a voltage drop along the line between the two through which the sample liquid flows from source to needle. This voltage drop causes an electric current to flow from the needle, through the connecting tube to the source of liquid sample.
  • the resulting current drain on the high voltage power supply can be minimized by making the connecting tube very long, thereby increasing its electrical resistance.
  • a high voltage power supply can be installed that has sufficient capacity to maintain the desired voltage on the injection needle in spite of the current drain.
  • the aperture leading into the vacuum system 4 can be a simple orifice or nozzle, but they both encounter problems of cost and safety.
  • a more advantageous method of maintaining the source of sample liquid at ground potential, a most desirable operating condition when the sample source is a Liquid Chromatograph, is to replace the orifice with a capillary 5 of dielectric material, e.g. glass, as shown in Fig. 1.
  • the spectra sometimes contain peaks for ions to be expected if there is a discharge in a gas containing o, N and C, i.e. 0-, NO-, CN-, NO2-, OCN- and o 2 -.
  • the indicated potential difference of 4540 V between the inlet and exit ends of the capillary may seem startling.
  • the carrier bath-gas nitrogen
  • the ion mobility is low enough so that the gas flow through the capillary can drag the ions out of the potential well at the capillary inlet and raise them back up to ground potential or as much as 15 kV above it.
  • the field at the needle tip charges the surface of the emerging liquid which becomes dispersed by Coulomb forces into a fine spray of charged droplets.
  • the droplets migrate toward the inlet end of the capillary through a countercurrent flow of bath gas typically at 800 torr, at an entering temperature from 320 to 350 K, and at a flow rate of about 100 mL/s.
  • bath gas typically at 800 torr, at an entering temperature from 320 to 350 K, and at a flow rate of about 100 mL/s.
  • the optimum values of temperature and flow rate depend upon the design details of a particular apparatus, the species being analyzed and the objectives of the experiment. Flow rates of the bath gas that are too high may decrease sensitivity by preventing analyte ions with low mobilities from reaching the entrance to the capillary.
  • the flow rates are too low the extent of ion solvation may be excessive. However, in some cases it may be desirable to retain a certain amount of solvation in the ions by decreasing the bath gas temperature and/or the flow rate. Thus, while useable ion beams will be obtained with the bath gas parameters at what have been indicated as typical values, a certain amount of trial and error is advisable for determining the best flow rate and temperature for a particular experiment in a particular apparatus.
  • the choice of bath gas is another important variable.
  • the gas should be inert in the sense of not undergoing reaction or charge exchange with analyte ions. In addition it should have a relatively high dielectric strength in order to avoid breakdown and discharge at the tip of the injection needle even when the applied voltages are relatively high. It is also desirable that the gas should be inexpensive if the apparatus is to run for long periods of time. We have found that nitrogen is generally satisfactory. Carbon dioxide also works very well for many species. Air would serve if it is free of contaminants that might make chemical noise in the spectrum.
  • Some of these desorbed ions are entrained in the flow of dry bath gas that enters the glass capillary to emerge at the exit end as a supersonic free jet in the first of two vacuum chambers. A core portion of this free jet passes through a skimmer into the second vacuum chamber, delivering ions to the mass analyzer.
  • a quadrupole mass filter was used. However, the invention may be practiced with any kind of mass analyzer as long as the m/z values of the ions to be analyzed are within its range.
  • ions produced by the ion sources traditionally used in mass spectrometry generally comprise singly charged species resulting from the loss or gain of an electron by a parent molecule.
  • the value of z is unity so that m/z which is what analyzers measure, is numerically equal to the mass of the ion.
  • an appreciable fraction of the ions are often charged fragments of the parent molecule.
  • ions produced by some of the more recently developed sources comprise neutral parent molecules to which small cations or anions are attached or from which protons or other charge bearing entities have been detached.
  • Table I summarizes the essential features of each mass spectrum shown in Fig. 2 and the information it provides. It is immediately apparent from the mass spectrum and Table I that the extent of multiple charging in ES ionization is much larger than has been encountered with any other soft ionization method. For example, the ionization of bovine insulin by FAB (xenon at 8-10 KeV) produced only the singly and doubly charge molecular ion. (see e.g. Desidero and Katakuse, Biomed. Mass Spectro ., 1984, 11 (2) , 55) This multiple charging feature of ES is very attractive in that it extends the effective mass range of any mass analyzer by a factor equal to the number of charges per ion.
  • the multiply charged ions have lower m/z values, they are generally easier to detect and "weigh" than are the corresponding singly charged ions of the same specie.
  • peak multiplicity distributes the signal for one species over several masses. For relatively large analyte molecules the number of charges per ion is almost always greater than the number of peaks. Therefore, the total current carried by one species is greater when there is peak multiplicity than would be the case for a single peak containing the same total number of singly charged ions.
  • the detector response per charge of a multiply charged ion is not known. It is known, however, that no post-acceleration has been required for multiply charged ions that were large enough to require such acceleration had they been singly charged.
  • K ⁇ is the value of m/z for a peak position on the scale of the mass analyzer and K'i ⁇ Kj - m a equals the m/z value of that peak position minus the adduct ion mass m a .
  • All masses are isotope averaged i.e., calculated using the chemical atomic weight scale. The positions of the peak maxima are used to determine the value of Kj. With the further constraint that i must be integral, equations 1 for any pair of peaks are in principle enough to determine the three unknowns simultaneously.
  • Equation of eqs. 1 for two charge states i and i+j (j > 0) yields for the number of charges i:
  • the accuracy required in K ⁇ for determining i is low, especially if K ⁇ -Ki+j is made large, but increases as i gets larger. From eq.
  • the parent ion mass M can be obtained from any one peak or averaged from a number of peaks:
  • n 0 is the number of those peaks.
  • the scatter of the pair- points around this line is a measure of the quality of the mass spectrum. The more accurate the mass determination, the closer to the line the point will fall.
  • Figure 3a shows such a plot for the cytochrome C mass spectrum of Figure 2.
  • the seven points at each abscissa value of 1/i correspond to the seven possible ratios of K'i/K'i+j for the eight peaks in the spectrum as i to i+j goes from 12 to 19.
  • Equation 6 defines a relative weighting factor for each peak i:
  • W is the normalizing constant and p is an integer equal to or greater than 2 which specifies the dependence of w on the proximity of the parent point to the straight line in Figure 3b.
  • i aV e ⁇ s an average number of charges per ion in the sequence of peaks
  • s is the standard deviation derived from averaging the individual peaks
  • ⁇ Da is the absolute value of the error in daltons of the mass scale calibration.
  • isotope spread does not contribute appreciably to peak broadening.
  • the contribution to peak half- width from the isotope distribution in a typical protein even at 100 kDa is less than 30 mass units (8) .
  • the corresponding spread in m/z is less than 0.3 mass units in a peak for ions with 100 charges, not an unreasonable number for such a large molecule.
  • F is the transformation function for which the argument M* is any arbitrarily chosen trial value of M for which F is to be evaluated.
  • m a is the adduct ion mass, as previously defined. It will be shown below that the function F has its maximum value when M equals the actual value of M, the parent mass of the multiply charged ions in the sequence.
  • evaluating F at all values of M with 0 ⁇ M ⁇ yields a transformed or "deconvoluted" spectrum, in which the peak with maximum height corresponds to the parent species with a single massless charge.
  • Figure 5b shows the results of applying eq.8 to the spectrum of Figure 5a, an ideal sequence of multiply charged ions with 6 ⁇ i ⁇ 15. It is a property of the spectrum resulting from the transformation F, as shown in Figure 5b, that it comprises a series of calculated peaks containing contributions from the actual peaks in an observed spectrum.
  • a number of general features of the deconvoluted spectrum can be inferred. As we have already noted, its most prominent peak occurs when M equals the parent mass M and has a magnitude equal to the sum of the magnitudes of the individual peaks in the sequence. The next highest peak occurs at M/2 and it is at most only half as high as the peak at M.
  • This periodicity may be viewed physically as being due to synthetic "overtones" of the basic spectrum corresponding to doubling, tripling etc. , both the parent mass and the number of charges on each peak, and a difference of 2,3 etc. in the i values of adjacent peaks.
  • Figure 7a displays the result of applying the deconvolution procedure to the mass spectrum of cytochrome C in Figure 2.
  • the transformed spectrum clearly shows the side peaks, the overtone periodicity and the baseline increase discussed above.
  • the parent (largest) peak is magnified in Figure 7b by "zoom" expansion of the mass scale in its vicinity.
  • Table IV summarizes the results for molecular weight determination from the spectra in Figure 2.
  • Figure 9 shows the mass spectrum for a solution of cytochrome C and myogolobin, each at a concentration of 0.5 mg/ml in an acidified mixture of acetonitrile, methanol and water. Also shown is the result of applying the deconvolution algorithm along with a "zoom" magnification of the pertinent parts of the deconvoluted spectrum.
  • the number of different species that a mixture can contain and still be resolved by this procedure depends upon their relative concentration in the mixture and different in their masses. The key factor is how close together are the peaks of the component multiply charged ions and whether the available analyzer can resolve them.

Abstract

Cette invention concerne la production de spectres de masses qui contiennent une multitude de crêtes. Les composants ioniques de ces crêtes, dont la charge a été multipliée, sont formés en dispersant une solution contenant un analyte dans un gaz d'un bain sous forme de gouttelettes fortement chargées. L'analyte est généralement un composé de poids moléculaire élevé et d'intérêt biochimique. L'invention concerne également des procédés de calcul du poids moléculaire de l'analyte à partir des valeurs de masse mesurées des ions fortement chargés.
EP19900909301 1989-05-19 1990-05-17 Multiply charged ions and a method for determining the molecular weight of large molecules Withdrawn EP0434792A4 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US35439389A 1989-05-19 1989-05-19
US354393 1989-05-19

Publications (2)

Publication Number Publication Date
EP0434792A1 true EP0434792A1 (fr) 1991-07-03
EP0434792A4 EP0434792A4 (en) 1992-05-20

Family

ID=23393139

Family Applications (1)

Application Number Title Priority Date Filing Date
EP19900909301 Withdrawn EP0434792A4 (en) 1989-05-19 1990-05-17 Multiply charged ions and a method for determining the molecular weight of large molecules

Country Status (5)

Country Link
EP (1) EP0434792A4 (fr)
JP (1) JPH04501468A (fr)
AU (1) AU5815590A (fr)
CA (1) CA2032490A1 (fr)
WO (1) WO1990014148A1 (fr)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US10055540B2 (en) 2015-12-16 2018-08-21 Gritstone Oncology, Inc. Neoantigen identification, manufacture, and use
US11264117B2 (en) 2017-10-10 2022-03-01 Gritstone Bio, Inc. Neoantigen identification using hotspots
US11885815B2 (en) 2017-11-22 2024-01-30 Gritstone Bio, Inc. Reducing junction epitope presentation for neoantigens

Families Citing this family (67)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5072115A (en) * 1990-12-14 1991-12-10 Finnigan Corporation Interpretation of mass spectra of multiply charged ions of mixtures
US5157260A (en) * 1991-05-17 1992-10-20 Finnian Corporation Method and apparatus for focusing ions in viscous flow jet expansion region of an electrospray apparatus
US6436635B1 (en) 1992-11-06 2002-08-20 Boston University Solid phase sequencing of double-stranded nucleic acids
US6194144B1 (en) 1993-01-07 2001-02-27 Sequenom, Inc. DNA sequencing by mass spectrometry
US5605798A (en) 1993-01-07 1997-02-25 Sequenom, Inc. DNA diagnostic based on mass spectrometry
WO1994016101A2 (fr) 1993-01-07 1994-07-21 Koester Hubert Sequençage d'adn par spectrometrie de masse
CA2158642A1 (fr) * 1993-03-19 1994-09-29 Hubert Koster Sequencage de l'adn par spectrometrie de masse, via la degradation de l'exonuclease
US5359196A (en) * 1993-05-24 1994-10-25 Hewlett-Packard Company Mass spectrometry with gas counterflow for particle beam
US5412208A (en) * 1994-01-13 1995-05-02 Mds Health Group Limited Ion spray with intersecting flow
US6146854A (en) * 1995-08-31 2000-11-14 Sequenom, Inc. Filtration processes, kits and devices for isolating plasmids
US5777324A (en) 1996-09-19 1998-07-07 Sequenom, Inc. Method and apparatus for maldi analysis
US6207370B1 (en) 1997-09-02 2001-03-27 Sequenom, Inc. Diagnostics based on mass spectrometric detection of translated target polypeptides
US6426191B1 (en) 1998-04-03 2002-07-30 Hyseq, Inc. Assays involving an IL-1 receptor antagonist
US6337072B1 (en) 1998-04-03 2002-01-08 Hyseq, Inc. Interleukin-1 receptor antagonist and recombinant production thereof
US6541623B1 (en) 1998-04-03 2003-04-01 Hyseq, Inc. Interleukin—1 receptor antagonist and uses thereof
US6294655B1 (en) 1998-04-03 2001-09-25 Hyseq, Inc. Anti-interleukin-1 receptor antagonist antibodies and uses thereof
US6447771B1 (en) 1999-03-19 2002-09-10 Hyseq, Inc. Methods and materials relating to novel CD39-like polypeptides
US6387645B1 (en) 1998-07-16 2002-05-14 Hyseq, Inc. Methods and materials relating to novel CD39-like polypeptides
JP2002520040A (ja) 1998-07-16 2002-07-09 ハイセック，インコーポレーテッド 新規ｃｄ３９様ポリペプチドに関する方法および材料
US6476211B1 (en) 1998-07-16 2002-11-05 Hyseq, Inc. Methods and materials relating to CD39-like polypeptides
US6350447B1 (en) 1999-01-29 2002-02-26 Hyseq, Inc. Methods and compositions relating to CD39-like polypeptides and nucleic acids
US6783959B1 (en) 1999-01-29 2004-08-31 Nuvelo, Inc. Methods and compositions relating to CD39-like polypeptides and nucleic acids
US6780977B1 (en) 1999-01-29 2004-08-24 Nuvelo, Inc. Methods and compositions relating to CD39-like polypeptides and nucleic acids
US6899875B1 (en) 1999-01-29 2005-05-31 Nuvelo, Inc. Methods and compositions relating to CD39-like polypeptides and nucleic acids
US6335013B1 (en) 1999-03-19 2002-01-01 Hyseq, Inc. Methods and materials relating to CD39-like polypeptides
US7015004B2 (en) 2001-11-23 2006-03-21 Syn X Pharma, Inc. Inter-alpha trypsin inhibitor biopolymer marker indicative of insulin resistance
US7008800B2 (en) 2001-04-30 2006-03-07 Artemis Proteomics, Ltd. Biopolymer marker indicative of disease state having a molecular weight of 1077 daltons
US6602855B2 (en) 2001-04-30 2003-08-05 Syn X Pharma, Inc. Biopolymer marker indicative of disease state having a molecular weight of 1449 daltons
US6593298B2 (en) 2001-04-30 2003-07-15 Syn X Pharma, Inc. Biopolymer marker indicative of disease state having a molecular weight of 1690 daltons
US7314717B2 (en) 2001-04-30 2008-01-01 Nanogen Inc. Biopolymer marker indicative of disease state having a molecular weight of 1562 daltons
US20040198950A1 (en) 2001-04-30 2004-10-07 George Jackowski Biopolymer marker indicative of disease state having a molecular weight of 1518 daltons
US7087435B2 (en) 2001-04-30 2006-08-08 Syn X Pharma, Inc. Biopolymer marker indicative of disease state having a molecular weight of 2753 daltons
US6693080B2 (en) 2001-04-30 2004-02-17 Syn X Pharma Biopolymer marker indicative of disease state having a molecular weight of 1521 daltons
US6627606B2 (en) 2001-04-30 2003-09-30 Syn X Pharma, Inc. Biopolymer marker indicative of disease state having a molecular weight of 1465 daltons
US6620786B2 (en) 2001-04-30 2003-09-16 Syn X Pharma, Inc. Biopolymer marker indicative of disease state having molecular weight of 2937 daltons
US6627608B2 (en) 2001-04-30 2003-09-30 Syn X Pharma, Inc. Biopolymer marker indicative of disease state having a molecular weight of 1206 daltons
US6620787B2 (en) 2001-04-30 2003-09-16 Syn X Pharma, Inc. Biopolymer marker indicative of disease state having a molecular weight of 2267 daltons
US7294688B2 (en) 2001-04-30 2007-11-13 Nanogen Inc. Biopolymer marker indicative of disease state having a molecular weight of 1348 daltons
US6627607B2 (en) 2001-04-30 2003-09-30 Syn X Pharma, Inc. Biopolymer marker indicative of disease state having a molecular weight of 1845 daltons
US20020160533A1 (en) 2001-04-30 2002-10-31 George Jackowski Biopolymer marker indicative of disease state having a molecular of weight of 1525 daltons
US6677303B2 (en) 2001-04-30 2004-01-13 Syn X Pharma Biopolymer marker indicative of disease state having a molecular weight of 1097 daltons
US6756476B2 (en) 2001-04-30 2004-06-29 Syn X Pharma, Inc. Biopolymer marker indicative of disease state having a molecular weight of 2021 daltons
US6703366B2 (en) 2001-04-30 2004-03-09 George Jackowski Biopolymer marker indicative of disease state having a molecular weight of 1,896 daltons
US6617308B2 (en) 2001-04-30 2003-09-09 Syn X Pharma, Inc. Biopolymer marker indicative of disease state having a molecular weight of 1865 daltons
US6599877B2 (en) 2001-04-30 2003-07-29 Syn X Pharma, Inc. Biopolymer marker indicative of disease state having a molecular weight of 1020 daltons
US6890763B2 (en) 2001-04-30 2005-05-10 Syn X Pharma, Inc. Biopolymer marker indicative of disease state having a molecular weight of 1350 daltons
CA2448097A1 (fr) 2001-05-22 2002-11-28 University Of Chicago Arn polymerase dependant de l'adn a brin unique de virion n4
US7179610B2 (en) 2001-11-23 2007-02-20 Nanogen Inc. Complement C3 precursor biopolymer markers indicative of insulin resistance
US7132244B2 (en) 2001-11-21 2006-11-07 Syn X Pharma, Inc. Betaine/GABA transport protein biopolymer marker indicative of insulin resistance
US7314762B2 (en) 2001-11-21 2008-01-01 Nanogen, Inc. Apolipoprotein biopolymer markers indicative of insulin resistance
US7094549B2 (en) 2001-11-23 2006-08-22 Syn X Pharma, Inc. Fibronectin biopolymer marker indicative of insulin resistance
US7074576B2 (en) 2001-11-23 2006-07-11 Syn X Pharma, Inc. Protein biopolymer markers indicative of alzheimer's disease
US7052849B2 (en) 2001-11-23 2006-05-30 Syn X Pharma, Inc. Protein biopolymer markers predictive of insulin resistance
US7122327B2 (en) 2001-11-23 2006-10-17 Nanogen Inc. Biopolymer markers indicative of type II diabetes
US7097989B2 (en) 2001-11-23 2006-08-29 Syn X Pharma, Inc. Complement C3 precursor biopolymer markers predictive of type II diabetes
US6890722B2 (en) 2001-11-23 2005-05-10 Syn X Pharma, Inc. HP biopolymer markers predictive of insulin resistance
US7179606B2 (en) 2001-11-23 2007-02-20 Syn X Pharma, Inc. IG heavy chain, IG kappa, IG lambda biopolymer markers predictive of Alzheimer's disease
US7026129B2 (en) 2001-11-23 2006-04-11 Syn X Pharma, Inc. IG lambda biopolymer markers predictive of Alzheimers disease
US7125678B2 (en) 2001-11-23 2006-10-24 Nanogen, Inc. Protein biopolymer markers predictive of type II diabetes
US7179605B2 (en) 2001-11-23 2007-02-20 Nanogen Inc. Fibronectin precursor biopolymer markers indicative of alzheimer's disease
US7135297B2 (en) 2001-11-23 2006-11-14 Nanogen Inc. Protein biopolymer markers indicative of insulin resistance
CN101512013A (zh) 2005-03-23 2009-08-19 生物-拉德实验室公司 与具有顺磁性质的小颗粒相连接的各种化学库
US20080317741A1 (en) 2005-11-16 2008-12-25 Anu Kinnunen Biomarkers For Anti-Nogo-A Antibody Treatment in Spinal Cord Injury
WO2009147699A1 (fr) * 2008-06-04 2009-12-10 株式会社島津製作所 Procédé d’analyse de données analytiques de masse et appareil d’analyse de données analytiques de masse
US10192725B2 (en) * 2013-12-24 2019-01-29 Waters Technologies Corporation Atmospheric interface for electrically grounded electrospray
AU2016297510B2 (en) 2015-07-17 2021-09-09 President And Fellows Of Harvard College Methods of amplifying nucleic acid sequences
GB2550591B (en) * 2016-05-24 2018-06-27 Microsaic Systems Plc A method for extracting mass information from low resolution mass-to-charge ratio spectra of multiply charged species

Family Cites Families (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3639757A (en) * 1969-08-04 1972-02-01 Franklin Gno Corp Apparatus and methods employing ion-molecule reactions in batch analysis of volatile materials
US3944826A (en) * 1973-07-19 1976-03-16 Applied Research Laboratories Limited Methods and apparatus for analyzing mixtures
DE2837715A1 (de) * 1978-08-30 1980-03-13 Leybold Heraeus Gmbh & Co Kg Verfahren zur analyse organischer substanzen
US4542293A (en) * 1983-04-20 1985-09-17 Yale University Process and apparatus for changing the energy of charged particles contained in a gaseous medium
GB2168478A (en) * 1984-11-26 1986-06-18 Scan Limited M Analysis of protein etc using mass spectrometry
US4667100A (en) * 1985-04-17 1987-05-19 Lagna William M Methods and apparatus for mass spectrometric analysis of fluids
US4755671A (en) * 1986-01-31 1988-07-05 Isomed, Inc. Method and apparatus for separating ions of differing charge-to-mass ratio
US4705616A (en) * 1986-09-15 1987-11-10 Sepragen Corporation Electrophoresis-mass spectrometry probe

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
See also references of WO9014148A1 *
ZEITSCHRIFT F]R PHYSIK , D AT. MOL. CLUSTERS vol. 10, no. 2-3, 1988, BERLIN, DE pages 361 - 368; FENN J B ET AL: 'OF PROTONS OR PROTEINS' *

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US10055540B2 (en) 2015-12-16 2018-08-21 Gritstone Oncology, Inc. Neoantigen identification, manufacture, and use
US10847253B2 (en) 2015-12-16 2020-11-24 Gritstone Oncology, Inc. Neoantigen identification, manufacture, and use
US10847252B2 (en) 2015-12-16 2020-11-24 Gritstone Oncology, Inc. Neoantigen identification, manufacture, and use
US11183286B2 (en) 2015-12-16 2021-11-23 Gritstone Bio, Inc. Neoantigen identification, manufacture, and use
US11264117B2 (en) 2017-10-10 2022-03-01 Gritstone Bio, Inc. Neoantigen identification using hotspots
US11885815B2 (en) 2017-11-22 2024-01-30 Gritstone Bio, Inc. Reducing junction epitope presentation for neoantigens

Also Published As

Publication number Publication date
JPH04501468A (ja) 1992-03-12
AU5815590A (en) 1990-12-18
CA2032490A1 (fr) 1990-11-20
WO1990014148A1 (fr) 1990-11-29
EP0434792A4 (en) 1992-05-20

Similar Documents

Publication Publication Date Title
US6118120A (en) Multiply charged ions and method for determining the molecular weight of large molecules
EP0434792A1 (fr) Ions a charge multiple et procede de determination du poids moleculaire de grandes molecules
Fenn et al. Electrospray ionization for mass spectrometry of large biomolecules
Siuzdak Mass spectrometry for biotechnology
US4999493A (en) Electrospray ionization interface and method for mass spectrometry
Dass Fundamentals of contemporary mass spectrometry
Vestal Methods of ion generation
AU636924B2 (en) Electrospray ion source for mass spectrometry
EP0964427B1 (fr) Dispositif et méthode de désorption et ionisation par laser assisté par matrice (MALDI) à pression ambiente
Ashcroft Ionization methods in organic mass spectrometry
Traldi et al. Quantitative applications of mass spectrometry
Banks Jr et al. [21] Electrospray ionization mass spectrometry
US5581080A (en) Method for determining molecular weight using multiply charged ions
Macha et al. Silver cluster interferences in matrix-assisted laser desorption/ionization (MALDI) mass spectrometry of nonpolar polymers
Desiderio Mass spectrometry: Clinical and biomedical applications
Busch A glossary for mass spectrometry
Chapman Mass spectrometry: ionization methods and instrumentation
Lemière Interfaces for lc-ms
Straub et al. Molecular weight determination of proteins from multiply charged ions using thermospray ionization mass spectrometry
Linscheid Instrumental developments in organic mass spectrometry
Mann et al. Electrospray mass spectrometry
Schmitz State of the Art in the LC/MS
Williams Fundamentals of mass spectrometry
Lasater Studies of sub-micron sized electrospray droplets in mass spectrometry
Fong A novel tip design for electrospray mass spectrometry at nanoliter flowrate

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): AT BE CH DE DK ES FR GB IT LI LU NL SE

17P Request for examination filed

Effective date: 19910514

A4 Supplementary search report drawn up and despatched

Effective date: 19920402

AK Designated contracting states

Kind code of ref document: A4

Designated state(s): AT BE CH DE DK ES FR GB IT LI LU NL SE

17Q First examination report despatched

Effective date: 19940622

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE APPLICATION IS DEEMED TO BE WITHDRAWN

18D Application deemed to be withdrawn

Effective date: 19960716