Diagnostic development and public health surveillance require technologies that provide specific identification and absolute quantification of protein biomarkers. Beside immunologically related techniques (e.g. enzyme-linked immunosorbent assay), MS is gaining increasing interest due to its high sensitivity and specificity. Furthermore, MS-based analyses are extremely accurate quantitatively, provided that suitable reference standards are available. Recently, the use of chemically synthesized isotope-labeled marker peptides for MS-based absolute quantification of proteins has led to major advances. However, we show here that the use of such peptides can lead to severe biases. In this work, we present an innovative strategy (Protein Standard Absolute Quantification) that uses in vitro-synthesized isotope-labeled full-length proteins as standards for absolute quantification. As those protein standards perfectly match the biochemical properties of the target proteins, they can be directly added into the samples to be analyzed, allowing a highly accurate quantification of proteins even in prefractionated complex samples. The power of our Protein Standard Absolute Quantification methodology for accurate absolute quantification of biomarkers was demonstrated both on water and urine samples contaminated with Staphylococcus aureus superantigenic toxins as typical biomarkers of public health interest. Diagnostic development and public health surveillance require technologies that provide specific identification and absolute quantification of protein biomarkers. Beside immunologically related techniques (e.g. enzyme-linked immunosorbent assay), MS is gaining increasing interest due to its high sensitivity and specificity. Furthermore, MS-based analyses are extremely accurate quantitatively, provided that suitable reference standards are available. Recently, the use of chemically synthesized isotope-labeled marker peptides for MS-based absolute quantification of proteins has led to major advances. However, we show here that the use of such peptides can lead to severe biases. In this work, we present an innovative strategy (Protein Standard Absolute Quantification) that uses in vitro-synthesized isotope-labeled full-length proteins as standards for absolute quantification. As those protein standards perfectly match the biochemical properties of the target proteins, they can be directly added into the samples to be analyzed, allowing a highly accurate quantification of proteins even in prefractionated complex samples. The power of our Protein Standard Absolute Quantification methodology for accurate absolute quantification of biomarkers was demonstrated both on water and urine samples contaminated with Staphylococcus aureus superantigenic toxins as typical biomarkers of public health interest. Mass spectrometry MS has greatly contributed to the maturation of proteomics (1Aebersold R. Constellations in a cellular universe.Nature. 2003; 422: 115-116Crossref PubMed Scopus (78) Google Scholar). It is now possible to characterize hundreds of proteins in an hour time frame and compare protein abundances in pairs of samples. The next frontier lies in accurate absolute quantitation. Although label-free spectral counting approaches (2Lu P. Vogel C. Wang R. Yao X. Marcotte E.M. Absolute protein expression profiling estimates the relative contributions of transcriptional and translational regulation.Nat. Biotechnol. 2007; 25: 117-124Crossref PubMed Scopus (916) Google Scholar, 3Mallick P. Schirle M. Chen S.S. Flory M.R. Lee H. Martin D. Ranish J. Raught B. Schmitt R. Werner T. Kuster B. Aebersold R. Computational prediction of proteotypic peptides for quantitative proteomics.Nat. Biotechnol. 2007; 25: 125-131Crossref PubMed Scopus (572) Google Scholar) are attracting considerable interest, robust absolute quantitative methodologies typically rely on the well-established isotope dilution principle (4Tai S.S. Bunk D.M. White E.T. Welch M.J. Development and evaluation of a reference measurement procedure for the determination of total 3,3′,5-triiodothyronine in human serum using isotope-dilution liquid chromatography-tandem mass spectrometry.Anal. Chem. 2004; 76: 5092-5096Crossref PubMed Scopus (72) Google Scholar), in which internal standardization is achieved with isotope-labeled homologs of specific proteolytic peptides from the target protein(s) (5Gerber S.A. Rush J. Stemman O. Kirschner M.W. Gygi S.P. Absolute quantification of proteins and phosphoproteins from cell lysates by tandem MS.Proc. Natl. Acad. Sci. U. S. A.,. 2003; 100: 6940-6945Crossref PubMed Scopus (1549) Google Scholar, 6Kirkpatrick D.S. Gerber S.A. Gygi S.P. The absolute quantification strategy: a general procedure for the quantification of proteins and post-translational modifications.Methods. 2005; 35: 265-273Crossref PubMed Scopus (484) Google Scholar). The Absolute Quantitation (AQUA) 1The abbreviations used are: AQUA, Absolute Quantification; AAA, amino acid analysis; MRM, multiple reaction monitoring; PSAQ, protein standard absolute quantification; QconCAT, concatemer of standard peptides for absolute quantification; SEA, staphylococcal enterotoxin A; SEB, staphylococcal enterotoxin B; TSST-1, toxic shock syndrome toxin-1. peptide strategy uses chemically synthesized isotope-labeled peptides which are spiked into the samples in known quantities before MS analysis (5Gerber S.A. Rush J. Stemman O. Kirschner M.W. Gygi S.P. Absolute quantification of proteins and phosphoproteins from cell lysates by tandem MS.Proc. Natl. Acad. Sci. U. S. A.,. 2003; 100: 6940-6945Crossref PubMed Scopus (1549) Google Scholar, 6Kirkpatrick D.S. Gerber S.A. Gygi S.P. The absolute quantification strategy: a general procedure for the quantification of proteins and post-translational modifications.Methods. 2005; 35: 265-273Crossref PubMed Scopus (484) Google Scholar, 7Stemmann O. Zou H. Gerber S.A. Gygi S.P. Kirschner M.W. Dual inhibition of sister chromatid separation at metaphase.Cell. 2001; 107: 715-726Abstract Full Text Full Text PDF PubMed Scopus (388) Google Scholar, 8Barr J.R. Maggio V.L. Patterson Jr., D.G. Cooper G.R. Henderson L.O. Turner W.E. Smith S.J. Hannon W.H. Needham L.L. Sampson E.J. Isotope dilution–mass spectrometric quantification of specific proteins: model application with apolipoprotein A-I.Clin. Chem. 1996; 42: 1676-1682Crossref PubMed Scopus (321) Google Scholar). Recently, the synthesis and metabolic labeling of an artificial concatemer of standard peptides (QconCAT), which can be spiked into the samples before trypsin digestion, was introduced to extend the number of quantified proteins (9Beynon R.J. Doherty M.K. Pratt J.M. S.J. absolute quantification in proteomics using artificial proteins of 2005; PubMed Scopus Google Scholar, mass spectrometric multiple reaction for major Full Text Full Text PDF PubMed Scopus Google Scholar, J.M. D.M. Doherty M.K. J. S.J. R.J. absolute quantification for proteomics using peptides by PubMed Scopus Google Scholar, J. D.M. S.J. R.J. Absolute quantitative analysis of protein expression development using 2007; Full Text Full Text PDF PubMed Scopus Google Scholar). Although and approaches the quantitative measurement of proteins in with peptides and from the a to into the of the before MS analysis; an with which is with samples J. J.M. D.G. R. R.J. Smith of the human 2005; PubMed Scopus Google and 3Mallick P. Schirle M. Chen S.S. Flory M.R. Lee H. Martin D. Ranish J. Raught B. Schmitt R. Werner T. Kuster B. Aebersold R. Computational prediction of proteotypic peptides for quantitative proteomics.Nat. Biotechnol. 2007; 25: 125-131Crossref PubMed Scopus (572) Google Scholar) a protein the of the quantification. here an Protein Standard Absolute Quantification strategy for the absolute quantification of proteins in complex samples. strategy is on the use of in vitro-synthesized isotope-labeled full-length proteins as standards for quantification. our we with the and using Staphylococcus aureus superantigenic toxins in water and urine samples as typical biomarkers of public health J.M. shock syndrome and an 2001; PubMed Scopus Google Scholar, of Staphylococcus PubMed Scopus Google Scholar). S. aureus superantigenic toxins and toxic shock syndrome are for severe in which the highly staphylococcal toxic shock syndrome J.M. shock syndrome and an 2001; PubMed Scopus Google Scholar, of Staphylococcus PubMed Scopus Google Scholar). toxic shock syndrome is related to the of and to and at a to as superantigenic staphylococcal specific properties and a major of of Staphylococcus PubMed Scopus Google Scholar). staphylococcal a as The for has the staphylococcal enterotoxin as a of and water staphylococcal and are with of Staphylococcus PubMed Scopus Google Scholar, T. D. M. J. of in Staphylococcus aureus with and 2005; PubMed Scopus Google Scholar, D. S. O. in Staphylococcus aureus 2007; PubMed Google Scholar). and staphylococcal superantigenic toxins the development of specific and As a is for the staphylococcal toxic shock Furthermore, is for the identification and quantification of toxins in contaminated water In this which the for for staphylococcal superantigenic and quantification. In this work, we present an MS-based methodology to and the staphylococcal superantigenic toxins and TSST-1, which are the toxins in staphylococcal toxic shock syndrome of Staphylococcus PubMed Scopus Google Scholar, T. D. M. J. of in Staphylococcus aureus with and 2005; PubMed Scopus Google Scholar). water and human urine as for surveillance and with the methodologies the of isotope-labeled full-length proteins as standards for MS-based absolute quantification. peptides synthesized by peptides quantified by amino acid analysis by the staphylococcal and from The of quantification standards and toxins in The protein was as in peptides from staphylococcal superantigenic toxins SEB, TSST-1, staphylococcal enterotoxin staphylococcal enterotoxin staphylococcal enterotoxin staphylococcal enterotoxin and staphylococcal enterotoxin to of the staphylococcal and in peptide into an artificial protein and to the artificial R.J. Doherty M.K. Pratt J.M. S.J. absolute quantification in proteomics using artificial proteins of 2005; PubMed Scopus Google and J.M. D.M. Doherty M.K. J. S.J. R.J. absolute quantification for proteomics using peptides by PubMed Scopus Google for The was synthesized from the and The was by reaction with and with the using the in The was with and and into the a was achieved using the The was into and was using we the before its use for protein synthesis protein was in using the to the with the we used the of the amino acid and we and by isotope-labeled and Isotope The isotope of and was and protein was in a and was in was on a using a in was water and quantification was by on a and isotope labeling was by and analysis S. aureus from the of the standard was synthesized as its is was using the The used for are in and with and and into the expression an strategy on biochemical and its an to a of the for proteins by synthesis T. M. M. H. M. of proteins by a 2004; PubMed Scopus Google Scholar). in and used for in protein synthesis in the of and as for and in a and on a using an The of isotope-labeled protein was by to the the peptide and the in a using a of and isotope-labeled and quantified by of the proteins and labeling by and The of and in standards was proteins and and for on using both Protein and The quantities of toxins for and a by a protein an accurate quantification. by with our standards on using evaluation of proteins in and using a PubMed Scopus Google Scholar). was on a with our the of and toxins to be the and the used in water samples contaminated with quantities of and was into of of spiked with toxins standards in was in using trypsin at a to toxins in at by and in peptides added in quantities into the that from a was and contaminated with quantities of and was into of of contaminated with standards in was on of to the of proteins the directly in of a and this standard was added in quantities into of the samples of a at for samples on from for for in and with In the of the toxins and QconCAT, protein and by of in for and with in the for by the with an for M. S. C. J. J. proteomics of from cell 2007; Full Text Full Text PDF PubMed Scopus Google Scholar). in water for before with was using trypsin to protein in at from the using in the and The by and peptides in of peptides added to the samples that spiked with MS analyses on a to a mass peptide on a a and with a from acid to acid The mass was in the with a of to analysis was used for in MS and with using from the achieved using an Full of are in Quantification was from of for peptide pairs on by of a specific mass with The to for was and staphylococcal toxins to and with The peptide by and peptides for of the toxins peptides to staphylococcal and in MS of marker peptides synthesized as peptides with peptides used for the and quantification of and staphylococcal superantigenic superantigenic of the specific peptides used for and quantification mass of the as peptide as peptide as peptide as peptide in a and staphylococcal toxins added in into was of peptides added to the peptide before the peptide pairs by a mass of in the MS of was to the total of the peptide and its standard The of a of the which was the added The and for added of toxins from to from from The of and the of the and the standard of the peptide standardization is a highly quantification strategy However, an the peptides was for peptide and for for such peptides quantified by the using AAA, and to the quantitative be for and a evaluation of the peptide by require standards to be highly to into the samples. on dilution of peptides can lead to of peptide by with peptides into the of the due to the of protein protein to In samples can from the (e.g. of the of Standard peptide both lead to an of the standard and of the the of by the peptide from of this standard peptide the peptides and by trypsin and led to an of and abundances and a major of the peptide strategy: into the of the peptides from the this is for proteins such as staphylococcal superantigenic which are known to be of Staphylococcus PubMed Scopus Google Scholar). and an isotope-labeled concatemer of staphylococcal superantigenic toxins marker peptides and In this we the peptides as The of multiple peptide standards for at the quantification was and analyzed, the marker peptides by analysis and in analysis The peptide was in analyses due to its high In with T. S. synthesis and amino isotope labeling of proteins for PubMed Scopus Google Scholar), the expression of in the of and a high of analysis of the isotope-labeled an and to mass of and peptides trypsin which greatly the of for quantification. for of the marker peptides by a mass of The of peptide a of the that was the added and of and in water samples using water samples contaminated with of and concatemer was added to the samples and in with the The peptides by used as standards in marker peptides the of and peptide that of is the of from the that the the quantification The of proteins to and the of the major In an to the of with the In the was added in known into water samples and was with the In the was and the was used as a of standard peptides to the As in and high the standard was the of the standard with the target proteins for and in at and in the standard was with the contaminated samples. Although the marker peptides be in they MS quantification we on the marker peptides that the for SEA, and for In with with the peptides and the peptide standards and is to the of peptide standards in the However, led to an of and by a and As staphylococcal are as of Staphylococcus PubMed Scopus Google Scholar) and are to be highly to trypsin (9Beynon R.J. Doherty M.K. Pratt J.M. S.J. absolute quantification in proteomics using artificial proteins of 2005; PubMed Scopus Google Scholar, J. D.M. S.J. R.J. Absolute quantitative analysis of protein expression development using 2007; Full Text Full Text PDF PubMed Scopus Google Scholar), the for this is to the toxins and the and toxins added in into water samples. samples spiked with known quantities of and The water samples in and as for and standards and However, due to amino acid staphylococcal and in at and marker peptides as highly specific standards for quantification of and in with standards was highly and the of SEA, the using the standard peptides highly from to from the of standard the dilution In the of TSST-1, the standard peptides and both a of In the of we contaminated human urine samples with and TSST-1, which are the toxins in staphylococcal toxic shock syndrome of Staphylococcus PubMed Scopus Google Scholar, T. D. M. J. of in Staphylococcus aureus with and 2005; PubMed Scopus Google Scholar). samples prefractionated on by and with samples spiked with peptides The standards directly added in known quantities into the urine samples. we the (9Beynon R.J. Doherty M.K. Pratt J.M. S.J. absolute quantification in proteomics using artificial proteins of 2005; PubMed Scopus Google Scholar) by its to that of the target toxins with the in an is with the and the peptides by and are from the The of to was by of peptides as quantification standards for staphylococcal superantigenic toxins toxins quantified in the present As the was in be on was introduced into the samples before The peptides the of which added to the samples before analysis as D.S. Gerber S.A. Gygi S.P. The absolute quantification strategy: a general procedure for the quantification of proteins and post-translational modifications.Methods. 2005; 35: 265-273Crossref PubMed Scopus (484) Google Scholar). In with the and quantification of and in water was in urine samples even the standards a high by proteins the of marker peptides and In toxins to for and for TSST-1, In the high protein the sensitivity in urine to for and to for the estimates of and with the standards with the added and the in is due to of standards at of the a major of with In was the strategy that an accurate of the toxins in this complex and for marker peptide and marker peptide and In from to and public health the specific and accurate quantification of proteins in complex samples a and protein this has by However, the of approaches on the and of high and high Although are to M.J. O. D. C. S. J. R. D. H. O. M. B. S. U. S. J. S. S. B. M. P. M. M. M. a of for analysis of the human 2007; PubMed Scopus Google Scholar), the of to analyses the of protein is possible S.A. Protein and the and to Biotechnol. PubMed Scopus Google Scholar). the power of MS-based proteomics can be to spectral counting approaches for this (2Lu P. Vogel C. Wang R. Yao X. Marcotte E.M. Absolute protein expression profiling estimates the relative contributions of transcriptional and translational regulation.Nat. Biotechnol. 2007; 25: 117-124Crossref PubMed Scopus (916) Google Scholar, 3Mallick P. Schirle M. Chen S.S. Flory M.R. Lee H. Martin D. Ranish J. Raught B. Schmitt R. Werner T. Kuster B. Aebersold R. Computational prediction of proteotypic peptides for quantitative proteomics.Nat. Biotechnol. 2007; 25: 125-131Crossref PubMed Scopus (572) Google Scholar). However, the and high of approaches for are by in measurement absolute quantitative methodologies require an internal standardization isotope dilution D.S. Gerber S.A. Gygi S.P. The absolute quantification strategy: a general procedure for the quantification of proteins and post-translational modifications.Methods. 2005; 35: 265-273Crossref PubMed Scopus (484) Google Scholar, M. Mass proteomics Chem. 2005; PubMed Scopus Google Scholar). The of highly isotope-labeled peptides the peptide strategy methodology has used to H. and quantification of in by liquid to and Chem. PubMed Scopus Google Scholar) protein with standards (5Gerber S.A. Rush J. Stemman O. Kirschner M.W. Gygi S.P. Absolute quantification of proteins and phosphoproteins from cell lysates by tandem MS.Proc. Natl. Acad. Sci. U. S. A.,. 2003; 100: 6940-6945Crossref PubMed Scopus (1549) Google Scholar, 6Kirkpatrick D.S. Gerber S.A. Gygi S.P. The absolute quantification strategy: a general procedure for the quantification of proteins and post-translational modifications.Methods. 2005; 35: 265-273Crossref PubMed Scopus (484) Google Scholar, 7Stemmann O. Zou H. Gerber S.A. Gygi S.P. Kirschner M.W. Dual inhibition of sister chromatid separation at metaphase.Cell. 2001; 107: 715-726Abstract Full Text Full Text PDF PubMed Scopus (388) Google Scholar). However, and quantification of isotope-labeled peptides this proteins of interest are quantified with a peptide M.K. Absolute quantification of the model in serum by using protein and isotope dilution mass 2004; PubMed Scopus Google Scholar, D. Rush J. D.M. P. J. T. M. J. and absolute quantification of from and Full Text Full Text PDF PubMed Scopus Google Scholar). and related proteins as a strategy for absolute quantification of proteins (9Beynon R.J. Doherty M.K. Pratt J.M. S.J. absolute quantification in proteomics using artificial proteins of 2005; PubMed Scopus Google Scholar, mass spectrometric multiple reaction for major Full Text Full Text PDF PubMed Scopus Google Scholar, J.M. D.M. Doherty M.K. J. S.J. R.J. absolute quantification for proteomics using peptides by PubMed Scopus Google Scholar, J. D.M. S.J. R.J. Absolute quantitative analysis of protein expression development using 2007; Full Text Full Text PDF PubMed Scopus Google Scholar). the and quantification of to peptides in a marker peptides a protein can be a can be used for of of isotope-labeled peptide protein expression the synthesis of peptides to by such as peptides peptides chemically to (9Beynon R.J. Doherty M.K. Pratt J.M. S.J. absolute quantification in proteomics using artificial proteins of 2005; PubMed Scopus Google Scholar), proteins be for the of protein The and of properties of an isotope-labeled peptide and its in the of However, for and standards are added at of the D.S. Gerber S.A. Gygi S.P. The absolute quantification strategy: a general procedure for the quantification of proteins and post-translational modifications.Methods. 2005; 35: 265-273Crossref PubMed Scopus (484) Google Scholar, mass spectrometric multiple reaction for major Full Text Full Text PDF PubMed Scopus Google Scholar). the introduced by and in and that the of full-length isotope-labeled proteins the biochemical properties of protein into the samples before biases. an strategy on the use of full-length isotope-labeled proteins as quantification standards are added into the samples before to the of and for biomarkers analysis in complex samples. the principle of isotope dilution to the with QconCAT, the to standard as a of our However, from our the in the of a are time can be into an expression in Furthermore, artificial proteins concatemer a to as and of the protein expression can be a isotope labeling is by in expression in (9Beynon R.J. Doherty M.K. Pratt J.M. S.J. absolute quantification in proteomics using artificial proteins of 2005; PubMed Scopus Google Scholar, mass spectrometric multiple reaction for major Full Text Full Text PDF PubMed Scopus Google Scholar, and labeling of proteins for and PubMed Scopus Google Scholar). However, in the of isotope-labeled in a and a of the amino of the protein and labeling of proteins for and PubMed Scopus Google Scholar) that in MS quantification. we protein expression and which a high isotope with T. S. synthesis and amino isotope labeling of proteins for PubMed Scopus Google Scholar, E.M. protein and labeling for proteomics.Nat. 2004; PubMed Scopus Google Scholar). is to toxic proteins and an that is for and health In this we present an in of the (5Gerber S.A. Rush J. Stemman O. Kirschner M.W. Gygi S.P. Absolute quantification of proteins and phosphoproteins from cell lysates by tandem MS.Proc. Natl. Acad. Sci. U. S. A.,. 2003; 100: 6940-6945Crossref PubMed Scopus (1549) Google Scholar, 6Kirkpatrick D.S. Gerber S.A. Gygi S.P. The absolute quantification strategy: a general procedure for the quantification of proteins and post-translational modifications.Methods. 2005; 35: 265-273Crossref PubMed Scopus (484) Google Scholar, 7Stemmann O. Zou H. Gerber S.A. Gygi S.P. Kirschner M.W. Dual inhibition of sister chromatid separation at metaphase.Cell. 2001; 107: 715-726Abstract Full Text Full Text PDF PubMed Scopus (388) Google Scholar, 8Barr J.R. Maggio V.L. Patterson Jr., D.G. Cooper G.R. Henderson L.O. Turner W.E. Smith S.J. Hannon W.H. Needham L.L. Sampson E.J. Isotope dilution–mass spectrometric quantification of specific proteins: model application with apolipoprotein A-I.Clin. Chem. 1996; 42: 1676-1682Crossref PubMed Scopus (321) Google Scholar) and (9Beynon R.J. Doherty M.K. Pratt J.M. S.J. absolute quantification in proteomics using artificial proteins of 2005; PubMed Scopus Google Scholar, mass spectrometric multiple reaction for major Full Text Full Text PDF PubMed Scopus Google Scholar, J.M. D.M. Doherty M.K. J. S.J. R.J. absolute quantification for proteomics using peptides by PubMed Scopus Google Scholar, J. D.M. S.J. R.J. Absolute quantitative analysis of protein expression development using 2007; Full Text Full Text PDF PubMed Scopus Google Scholar), to our methodology for quantification. The of staphylococcal superantigenic toxins and as typical biomarkers that be added to water samples in a of the of the that in we a of a concatemer and full-length isotope-labeled toxins to and in water and urine samples. In contaminated peptides peptides and for the quantification of protein in serum using peptides J. J. H. B. Quantification of protein in the serum of with using multiple reaction mass spectrometry and peptide 2004; PubMed Scopus Google Scholar). from in trypsin which are for peptides are with the standard the marker peptides of a However, due to to standard led to an of the toxins the strategy demonstrated a and approaches for quantification in water both in of and The of from the of standard the dilution before an was for both and in urine samples and In with water the standard that used for urine samples which protein on both and the of the to use for the quantification of protein is on an on and the of a standard peptide can be (e.g. the standard peptide is by The which protein and a robust quantification of the As by and mass spectrometric multiple reaction for major Full Text Full Text PDF PubMed Scopus Google Scholar) for proteins, the to a peptide can to trypsin for a for peptide In a standards the of quantification strategy the to peptide The to the and strategy for quantitative analysis of biomarkers in was demonstrated by the quantification of and toxins in a complex (e.g. and with water the protein of urine samples high and that MS of marker the both and the The of the strategy to protein was the was for our standards quantification this with the MS as a before quantification of to proteins mass spectrometric multiple reaction for major Full Text Full Text PDF PubMed Scopus Google Scholar, J. J.M. D.G. R. R.J. Smith of the human 2005; PubMed Scopus Google Scholar). are on prefractionated protein samples D.S. Gerber S.A. Gygi S.P. The absolute quantification strategy: a general procedure for the quantification of proteins and post-translational modifications.Methods. 2005; 35: 265-273Crossref PubMed Scopus (484) Google Scholar, S.A. Protein and the and to Biotechnol. PubMed Scopus Google Scholar). As in the present on the of the target protein due to can quantification that are using the major of the strategy and of sensitivity was the of the present the staphylococcal superantigenic toxins be at the in water samples using our quantification of toxins be achieved to to of in the was of the standardization procedure AQUA, QconCAT, PSAQ, and is to the a to that is and quantitative for of staphylococcal J. of Scholar). In due to the of the and standards quantification of and to the to in the with a on staphylococcal enterotoxin MS-based quantification and quantification of staphylococcal enterotoxin in using liquid spectrometry.Anal. Chem. PubMed Scopus Google Scholar), in which the of quantification of spiked in was to be a protein of human urine with we demonstrated a quantification in this complex can be to the of sensitivity of the In the we to the sensitivity of our quantification procedure the use of multiple reaction The power of to the protein and high of such as urine mass spectrometric multiple reaction for major Full Text Full Text PDF PubMed Scopus Google Scholar, B. Aebersold R. Mass spectrometry and protein PubMed Scopus Google Scholar, J.R. M.K. reaction to of protein with high 2005; Full Text Full Text PDF PubMed Scopus Google Scholar). The of in the of the quantification this the to peptide standards by the strategy can be a with peptide the using peptide post-translational in a marker peptide quantification of the The protein by the strategy can the and quantification of of protein of interest. It is a the of proteins such as staphylococcal superantigenic toxins S. B. J. toxins and staphylococcal from the enterotoxin PubMed Scopus Google Scholar). demonstrated the of our strategy approaches for absolute quantification in complex such as the high sensitivity of MS a protein expression of a standard for of quantification such as to quantitative can be In this as was for S. in 2001; PubMed Scopus Google Scholar), we to a for the of reference for protein biomarkers. extend the standardization of the to the of biomarkers and by accurate quantitative proteomics M. J. D. M. H. D. J. C. J. J. D. E.M. T. a to the and to to 2007; PubMed Scopus Google Scholar).
No takes yet. Share an insight, caveat, or question.
Brun et al. (2007) studied this question.
Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context: