Cambridge Isotope Laboratories, Inc.
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MS/MS STANDARDS

MS/MS Screening
Mixtures and Standards

Cambridge Isotope Laboratories, Inc.
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| MS/MS Screening Mixtures and Standards

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Table of Contents
Compounds
Amino Acid Reference Standard Mixtures  ­ 2Steroid Reference Standard Mixtures  ­83-Plex Amino Acid Reference Standard Mixtures  ­ 3Additional Standard Mixtures for Screening  ­9Branched-chain Amino Acid Reference Standard Mixtures  ­4
Succinylacetone Reference Standard  ­11Carnitine and Acylcarnitine Reference Standard Mixtures  ­5Additional Example Standards for Screening  ­12­6Supplemental Acylcarnitine Reference Standard Mixtures

MS/MS Parameter Examples­ 14

Lysophosphatidylcholine (LPC) Reference Standard Mixtures ­7
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For research use only. Not for use in diagnostic procedures.

Amino Acid Reference Standard Mixtures (NSK-A and NSK-A1)
These sets contain 10 vials of a dry mixture of 12 stable isotope-labeled amino acids. Accurate and complete reconstitution of one vial’scontents in 1 mL of high-purity solvent will produce the concentrations listed in the table below. Individual vials are also available.
Example Reconstitution Approach for Concentrated Stock•	Solubilize the dried-down mix in 1 mL of 1:1 purified water:methanol.
•	Vortex manually for 1 minute then auto-vortex for 30 minutes or until complete reconstitution is achieved.
Aliquots of the concentrated stock can then be processed, diluted, and /or stored as indicated below.
Example Dilution Approaches for Working StockTo prepare working stock solutions:•	Dilute 1 mL (or an aliqout) of the reconstituted vial contents (per instructions above) with pure solvent.
•	If NSK-B (Carnitine/Acylcarnitine Standard Mix Set B) was purchased, mix 1 mL (or an aliquot of the reconstituted vial contents)of concentrated standards from Set A with 1 mL (or an aliquot) of the concentrated standards from Set B.
Composition
Standard (Abbreviation)
L-Alanine (Ala)
L-Arginine·HCl (Arg)
L-Aspartic acid (Asp)
L-Citrulline (Cit)DL-Glutamic acid (Glu)
Glycine (Gly)
L-Leucine (Leu)
L-Methionine (Met)
L-Ornithine·HCl (Orn)*
L-Phenylalanine (Phe)
L-Tyrosine (Tyr)
L-Valine (Val)Usage Specifications
Label and Enrichment
2,3,3,3-D4, 98%
5-13C, 99%; 4,4,5,5-D4, 95%
2,3,3-D3, 98%
5,5-D2, 98%
2,4,4-D3, 98%
2-13C, 99%; 15N, 98%
5,5,5-D3, 99%
methyl-D3, 98%
5,5-D2, 98%
ring-13C6, 99%
ring-13C6, 99%
D8, 98%MW (Da)93.12
215.68136.12
177.20150.1577.05
134.19152.23170.63
171.15187.14125.20Conc. (µM)
500
500
500
500
500
2500
500
500
500
500
500
500

*NSK-A1 contains Orn 3,3,4,4,5,5,-D6, 98% (MW 174.66 Da). The remaining
components are equivalent to NSK-A.
Note: A complementary set of these unlabeled amino acid reference
standards (NSK-A-US-1) and/or a combined set with NSK-B (i.e., NSK-AB)
is also available.

Chemical purity (CP) is 98% or greater, unless otherwise specified.

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Criteria
Recommendation
Use
960 samples/vial
Before reconstitution:
Storage≤25ºC; protect from light
Recommended retest
4 years from date of manufacture
After reconstitution:
Storage
Store in a tightly sealed vial at
5±3ºC. To maintain the integrity ofthe solution, store the sealed vials
in a second sealed container.
Recommended retest
4 weeks

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3-Plex Amino Acid Reference Standard Mixtures (NSK-AA3)
This dried-down mix comprises three stable isotope-labeled amino acids. Accurate and complete reconstitution of the vial’s contents in 1 mLof highly pure water will produce the concentrations listed in the table below.
Example Reconstitution Approach for Concentrated Stock•	Solubilize the dried-down mix in 1 mL of solvent (e.g., 1:1 purified water:acetonitrile)•	Vortex manually for 1 minute then auto-vortex for 30 minutes or until complete reconstitution is achieved.
Aliquots of the concentrated stock can then be processed, diluted, and /or stored as indicated below.
Example Dilution Approach for Working StockTo prepare working stock solutions, dilute 1 mL (or an aliqout) of the reconstituted vial contents (per instructions above) of the concentrated
amino acid standard with pure solvent.
Composition
Standard (Abbreviation)
Creatine (Cre)Label and Enrichment
N-Methyl-D3; glycine-2,2-D2, 99%

MW (Da)154.18Conc. (µM)
500

Structure
CD3 O

H 2N

N

OH

NH D D

Guanidinoacetic acid (GAA)

1,2-13C2, 97-99%; 3-15N, 97-99% (CP 97%)120.09

NH

50
H 2N

L-Proline (Pro)D7, 97-98%

122.17

500

D
D

D

N
H
D

D

N
H

OH
O
D
D

OH

O

Note: The concentrations are also available at 10X (NSK-AA3-10X).

Usage Specifications
Criteria
Recommendation
Before reconstitution:
Storage-5 to 5ºC; protect from light
Recommended retest
2 years from date of manufacture
After reconstitution:*
Storage-20ºC
Recommended retest
3 months*Represents minimum stability period when AA3 mix is reconstituted with 1:1 purified water:acetonitrile.

Chemical purity (CP) is 98% or greater, unless otherwise specified.

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Branched-Chain Amino Acid Reference Standard Mixtures (NSK-BCAA)This dried-down mix comprises four stable isotope-labeled amino acids. Accurate and complete reconstitution of the vial’s contents in 1 mLof highly pure water will produce the concentrations listed in the table below.
Example Reconstitution Approach for Concentrated Stock•	Solubilize the dried-down mix in 1 mL of solvent (e.g., 0.1 M HCl)•	Vortex manually for 1 minute then auto-vortex for 30 minutes or until complete reconstitution is achieved.
Aliquots of the concentrated stock can then be processed, diluted, and /or stored as indicated below.
Example Dilution Approach for Working StockTo prepare working stock solutions, dilute 1 mL (or an aliqout) of the reconstituted vial contents (per instructions above) of the concentrated
amino acid standard with pure solvent.
Composition
Standard (Abbreviation)
L-Allo-isoleucine (Alle)
L-Isoleucine (Ile)
L-Leucine (Leu)
L-Valine (Val)Label and Enrichment
13
C6, 97-99%; 15N, 97-99%
D10, 98%
5,5,5-D3, 99%
13
C5, 99%; 15N, 99%

MW (Da)
138.2
141.2
134.2
123.1

Conc. (µM)
400
400
400
400

Note: A mix of unlabeled BCAA standards (NSK-BCAA-US) is also available.

Usage Specifications
Criteria
Recommendation
Before reconstitution:
Storage≤25ºC; protect from light and moisture
Recommended retest
5 years from date of manufacture
After reconstitution:*
Storage
4°C
Recommended retest
5 weeks

Intensity (cps)*Represents minimum stability period when the BCAA mix is reconstituted with 100% water.

2.4e7
2.2e7
2.0e7
1.8e7

13

C5/15N Val
RT 10.80

13

C6/ N Alle
RT 10.21
15

D3 LeuRT 11.11

D10 IleRT 11.90

1.6e7
1.4e7
1.2e7
1.0e7
8.0e6
6.0e6
4.0e6
2.0e6
6.0

6.5

7.0

7.5

8.0

8.5

9.0

9.5

10.0 10.5 11.0 11.5 12.0 12.5 13.0 13.5

Time (min)Figure. Representative XICs of the BCAA mix metabolites measured by RPLC-MRM/MS (ESI+, 5500+ QqQ). Separation of
the isobaric metabolites is shown in the main plot, with Val in the inset. Displayed are the [M+H]+ ions (see Table on page
16 for precursor and product ion values).

Chemical purity (CP) is 98% or greater, unless otherwise specified.

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Carnitine and Acylcarnitine Reference Standard Mixtures (NSK-B)
This set contains 10 vials of a dry mixture of eight stable isotope-labeled free carnitine and acylcarnitines. Accurate and complete
reconstitution of one vial’s contents in 1 mL of high-purity solvent will produce the concentrations listed in the table below. Individualvials are also available.
Example Reconstitution Approach for Concentrated Stock•	Solubilize the dried-down mix in 1 mL of highly pure methanol.
•	Vortex manually for 1 minute then auto-vortex for 30 minutes or until complete reconstitution is achieved.
Aliquots of the concentrated stock can then be processed, diluted, and /or stored as indicated below.
Example Dilution Approaches for Working StockTo prepare working stock solutions:•	Dilute 1 mL (or an aliqout) of the reconstituted vial contents (per instructions above) with pure solvent.
•	If NSK-A (Amino Acid Standard Mix Set A) was purchased, mix 1 mL (or an aliquot) of the reconstituted vial contents of concentrated
standards from Set B with 1 mL (or an aliquot) of the concentrated standards from Set A.
Composition
Standard (Abbreviation)
L-Carnitine (C0)O-Acetyl-L-carnitine·HCl (C2)O-Propionyl-L-carnitine·HCl (C3)
O-Butyryl-L-carnitine·HCl (C4)O-Isovaleryl-L-carnitine·HCl (C5)O-Octanoyl-L-carnitine·HCl (C8)O-Myristoyl-L-carnitine·HCl (C14)
O-Palmitoyl-L-carnitine·HCl (C16)

Usage Specifications
Label and Enrichment
trimethyl-D9, 98%
N-methyl-D3, 98%
N-methyl-D3, 98%
N-methyl-D3, 98%
N,N,N-trimethyl-D9, 98%
N-methyl-D3, 98%
N,N,N-trimethyl-D9, 98%
N-methyl-D3, 98%

MW (Da)170.25242.72
256.74270.77290.83326.87417.07439.09Conc. (µM)
152
38
7.6
7.6
7.6
7.6
7.6
15.2

Note: A complementary set of these unlabeled carnitine/acylcarnitine standards(NSK-B-US-1) and a combined set with NSK-A (i.e., NSK-AB) is also available.

Criteria
Recommendation
Use
960 samples/vial
Before reconstitution:
Storage≤8ºC; protect from light
Recommended retest
1 year from date of manufacture
After reconstitution:
Storage
Store in a tightly sealed vial at
5±3ºC. To maintain the integrity ofthe solution, store the sealed vials
in a second sealed container.
Recommended retest
4 weeks

Example References
Lv, Y.; Zheng, Y.; Zhao, X.; et al. 2023. The relationship between islet β-cell function and metabolomics in overweight patients with Type 2 diabetes. Biosci Rep, 43(2),BSR20221430-BSR20221444.
Schupper, A.; Almashanu, S.; Coster, D.; et al. 2021. Metabolic biomarkers of small and large for gestational age newborns. Early Hum Dev, 160, 105422-105429.
Staretz-Chacham, O.; Daas, S.; Ulanovsky, I.; et al. 2021. The role of orotic acid measurement in routine newborn screening for urea cycle disorders. J Inherit Metab Dis, 44(3),606-617.
Brennenstuhl, H.; Kohlmüller, D.; Gramer, G.; et al. 2020. High throughput newborn screening for aromatic ι-amino-acid decarboxylase deficiency by analysis of concentrations of
3-O-methyldopa from dried blood spots. J Inherit Metab Dis, 43(3), 602-610.
Bai, Q.; Peng, B.; Wu, X.; et al. 2018. Metabolomic study for essential hypertension patients based on dried blood spot mass spectrometry approach. IUBMB Life, 70(8), 777-785.
Céspedes, N.; Valencia, A.; Echeverry, C.A.; et al. 2017. Reference values of amino acids, acylcarnitines and succinylacetone by tandem mass spectrometry for use in newborn
screening in southwest Colombia. Colomb Med (Cali), 48(3), 113-119.
Haynes, C.A.; De Jesús, V.R. 2016. Simultaneous quantitation of hexacosanoyl lysophosphatidylcholine, amino acids, acylcarnitines, and succinylacetone during FIA-ESI-MS/MS
analysis of dried blood spot extracts for newborn screening. Clin Biochem, 49(1-2), 161-165.
Wang, Q.; Sun, T.; Cao, Y.; et al. 2016. A dried blood spot mass spectrometry metabolomic approach for rapid breast cancer detection. Onco Targets Ther, 9, 1389-1398.
Huang, T.; Cao, Y.; Zeng, J.; et al. 2016. Tandem mass spectrometry-based newborn screening strategy could be used to facilitate rapid and sensitive lung cancer diagnosis.
Onco Targets Ther, 9, 2479-2487.
George, R.S.; Moat, S.J. 2016. Effect of dried blood spot quality on newborn screening analyte concentrations and recommendations for minimum acceptance criteria forsample analysis. Clin Chem, 62(3), 466-475.

Note: These references utilize NSK-A and NSK-B.
Technical Note
Xie, X.; Kozak, M. 2020. Simultaneous analysis of amino acids, acylcarnitines, and succinylacetone in dried blood spots for research using nonderivatized and derivatized methods.
(Thermo Scientific technical note #73398).

Chemical purity (CP) is 98% or greater, unless otherwise specified.

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Supplemental Acylcarnitine Reference Standard Mixtures (NSK-B-G1)
This set contains 10 vials of a dry mixture of five stable isotope-labeled acylcarnitines. Accurate and complete reconstitution of one vial’scontents in 1 mL of high-purity solvent will produce the concentrations listed in the table below. Individual vials are also available.
Example Reconstitution Approach for Concentrated Stock•	Solubilize the dried-down mix in 1 mL of highly pure methanol.
•	Vortex manually for 1 minute then auto-vortex for 30 minutes or until complete reconstitution is achieved.
Aliquots of the concentrated stock can then be processed, diluted, and /or stored as indicated below.
Example Dilution Approaches for Working StockTo prepare working stock solutions:•	Dilute 1 mL (or an aliqout) of the reconstituted vial contents (per instructions above) with pure solvent.
•	Mix 1 mL (or an aliquot) of the reconstituted vial contents of concentrated standards from NSK-A with 1 mL (or an aliquot) of theconcentrated standards from NSK-B and 1 mL (or an aliquot) of the concentrated standards from NSK-B-G1.
Composition
Standard (Abbreviation)
O-Glutaryl-L-carnitine·ClO4(C5-DC)
3-Hydroxyisovaleryl-Lcarnitine·ClO4 (C5-OH)
O-Dodecanoyl-Lcarnitine·HCl (C12)
O-3-DL-Hydroxypalmitoyl-Lcarnitine·ClO4 (C16-OH)
O-Octadecanoyl-Lcarnitine·HCl (C18)

Usage Specifications
Label and Enrichment
N-methyl-D3, 98% (CP 97%)

MW (Da)378.78Conc. (µM)
15.2

N-methyl-D3, 98%

364.79

7.6

N,N,N-trimethyl-D9, 98%

389.02

7.6

N-methyl-D3, 98%

519.0815.2

N-methyl-D3, 98%

467.1515.2

Criteria
Recommendation
Use
960 samples/vial
Before reconstitution:
Storage-5 to 5°C; protect from light
Recommended retest
2 years from date of manufacture
After reconstitution:
Storage
Store in a tightly sealed vial at
5±3ºC. To maintain the integrity ofthe solution, store the sealed vials
in a second sealed container.
Recommended retest
4 weeks

Note: A complementary set of these unlabeled acylcarnitine standards (NSK-B-G1-US) is
also available.

Example References
Schupper, A.; Almashanu, S.; Coster, D.; et al. 2021. Metabolic biomarkers of small and large for gestational age newborns. Early Hum Dev, 160, 105422.
Staretz-Chacham, O.; Daas, S.; Ulanovsky, I.; et al. 2021. The role of orotic acid measurement in routine newborn screening for urea cycle disorders. J Inherit Metab Dis, 44(3),606-617.
Céspedes, N.; Valencia, A.; Echeverry, C.A.; et al. 2017. Reference values of amino acids, acylcarnitines and succinylacetone by tandem mass spectrometry for use in newborn
screening in southwest Colombia. Colomb Med (Cali), 48(3), 113-119.
Simcox, J.; Geoghegan, G.; Maschek, J.A.; et al. 2017. Global analysis of plasma lipids identifies liver-derived acylcarnitines as a fuel source for brown fat thermogenesis.
Cell Metab, 26(3), 509-522.
Haynes, C.A.; De Jesús, V.R. 2016. Simultaneous quantitation of hexacosanoyl lysophosphatidylcholine, amino acids, acylcarnitines, and succinylacetone during FIA-ESI-MS/MS
analysis of dried blood spot extracts for newborn screening. Clin Biochem, 49(1-2), 161-165.
George, R.S.; Moat, S.J. 2016. Effect of dried blood spot quality on newborn screening analyte concentrations and recommendations for minimum acceptance criteria forsample analysis. Clin Chem, 62(3), 466-475.
Technical Note
Xie, X.; Kozak, M. 2020. Simultaneous analysis of amino acids, acylcarnitines, and succinylacetone in dried blood spots for research using nonderivatized and derivatized methods.
(Thermo Scientific technical note #73398).

Chemical purity (CP) is 98% or greater, unless otherwise specified.

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Lysophosphatidylcholine Reference Standard Mixtures (NSK-LPC)
This dried-down mix comprises four lysophosphatidylcholine (LPC or Lyso-PC) standards. Accurate and complete reconstitution of the vial’scontents in 1 mL of high-purity solvent will produce the concentrations listed in the table below.
Example Reconstitution Approach for Concentrated Stock•	Solubilize the dried-down mix in 1 mL of 95%:5% (v/v) methanol:water.
•	Sonicate the reconstituted vial for 3 minutes then auto-vortex for 10 seconds or until complete dissolution is achieved.
Aliquots of the concentrated stock can then be processed, diluted, and /or stored as indicated below.
Example Dilution Approach for Working StockTo prepare working stock solutions, dilute 1 mL (or an aliqout) of the reconstituted vial contents (per instructions above) with pure solvent.
Composition
Standard (Abbreviation)
Lysophosphatidylcholine 20:0
(LysoPC C20:0)

Label and Enrichment
eicosanoyl-12,12,13,13-D4, 98%

MW (Da)555.77

Lysophosphatidylcholine 22:0
(LysoPC C22:0)

docosanoyl-1,2,3,4,5,6-13C6, 99%

585.75

Lysophosphatidylcholine 24:0
(LysoPC C24:0)

tetracosanoyl-1,2,3,4,5,6-13C6, 99%

613.81

Lysophosphatidylcholine 26:0
(LysoPC C26:0)

hexacosanoyl-1,2,3,4,5,6-13C6, 99%

641.85

Conc. (µM)
5.5StructureP

CH3(CH2)6(CD2)2(CH2)10

5.5
CH3(CH2)15(CH2)5

5.5
CH3(CH2)17(CH2)5

5.5
CH3(CH2)19(CH2)5

P

P

P

Note: A mix of unlabeled LPC standards (NSK-LPC-US) is also available.

Usage Specifications
Criteria

Recommendation

Use~765 samples/vial

Before reconstitution:
Storage-20°C; protect from light

Recommended retest

2 years from date of manufacture

After reconstitution:
Storage5±3ºC or -20±5ºC

Recommended retest

6 weeks

Chemical purity (CP) is 98% or greater, unless otherwise specified.

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Steroid Reference Standard Mixtures (NSK-S and NSK-S-EXP)
These sets contain 10 vials of dried-down stable isotope-labeled steroids. Accurate and complete reconstitution of one vial’s contents in
1 mL of high-purity solvent will produce the concentrations listed in the table below. Vials of the individual mixes and compounds are alsoavailable.
Example Reconstitution Approach for Concentrated Stock•	Solubilize the dried-down mix in 1 mL of highly pure methanol.
•	Vortex manually for 1 minute then auto-vortex for 30 minutes or until complete reconstitution is achieved.
Aliquots of the concentrated stock can then be processed, diluted according to the following instructions, or stored as indicated below.
Example Dilution Approach for Working StockTo prepare working stock solutions, dilute 1 mL (or an aliqout) of the reconstituted vial contents (per instructions above) with pure solvent.
Steroid Mix Set S (NSK-S)
Composition
Standard (Abbreviation)
4-Androstene-3,17-dione (A4)
Cortisol (F)11-Deoxycortisol (11-S)
21-Deoxycortisol (21-S)
17α-Hydroxyprogesterone(17-OHP)

Usage Specifications
Label and Enrichment
2,2,4,6,6,16,16-D7, 97%
9,11,12,12-D4, 98%
2,2,4,6,6-D5, 98%
2,2,4,6,6,21,21,21-D8, 97%
2,2,4,6,6,21,21,21-D8, 98%

MW (Da)293.45366.49351.49354.51
338.51

Conc. (nM)
20
100
20
20
20

Note: The concentrations are also available at 40X (NSK-S-40X).

Criteria
RecommendationUse
48 samples/vial
Before reconstitution:
Storage-5 to 5°C; protect from light
Recommended retest
5 years from date of manufacture
After reconstitution:
Storage
Store in a tightly sealed vial at
5±3ºC. To maintain the integrity ofthe solution, store the sealed vials
in a second sealed container.
Recommended retest
4 weeks

Example ReferencesLai, F.; Srinivasan, S.; Wiley, V. 2020. Evaluation of a two-tier screening pathway for congenital adrenal hyperplasia in the New South Wales Newborn Screening Programme.
Int J Neonatal Screen, 6(3), 63-74.
Gervasoni, J.; Schiattarella, A.; Primiano, A.; et al. 2016. Simultaneous quantification of 17-hydroxyprogesterone, androstenedione, testosterone and cortisol in human serumby LC-MS/MS using TurboFlow online sample extraction. Clin Biochem, 49(13-14), 998-1003.
Hicks, R.A.; Yee, J.K.; Mao, C.S.; et al. 2014. Precursor-to-product ratios reflect biochemical phenotype in congenital adrenal hyperplasia. Metabolomics, 10(1), 123-131.
Dhillon, K.; Ho, T.; Rich, P.; et al. 2011. An automated method on analysis of blood steroids using liquid chromatography tandem mass spectrometry: application to population
screening for congenital adrenal hyperplasia in newborns. Clin Chem Acta, 412(23-24), 2076-2084.

Expanded Steroid Mix Set S (NSK-S-EXP)
Composition
Standard (Abbreviation)
Aldosterone (A)4-Androstene-3,17-dione (A4)
Corticosterone (B)Cortisol (F)Dehydroepiandrosterone
sulfate·sodium salt·2H2O(DHEAS)
11-Deoxycortisol (11-S)
17-α-Hydroxyprogesterone(17-OHP)
Progesterone (P)Testosterone (T)Usage Specifications

Label and Enrichment
D7, 98%2,2,4,6,6-D5, 98%
2,2,4,6,6,17α,21,21-D8,
97-98%
9,12,12-D3, 98%
2,2,3,4,4,6-D6, 95%

MW (Da)367.49291.44354.51

Conc. (µM)
0.52
0.12
1.58

365.48432.54

2.57
21.69

2,2,4,6,6-D5, 98% (CP 97%)
2,2,4,6,6,21,21,21-D8, 98%

351.49338.510.54
0.27

2,2,4,6,6,17α,21,21,21-D9,
98%
2,2,4,6,6-D5, 98%

323.520.14

293.46

0.12

Chemical purity (CP) is 98% or greater, unless otherwise specified.

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Criteria
Recommendation
Before reconstitution:
Storage-5 to 5°C; protect from light
Recommended retest
1 year from date of manufacture

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Additional Standard Mixtures for Screening
The additional products outlined below are available as individual dried-down mixtures of their substrate and internal standard.

α-Galactosidase Substrate and Internal Standard Mix (NSK-FA-1)
Each vial contains the following compounds at a molar ratio of 500:1.
Substrate(6-Benzoylamino-hexyl)-{2-[4-(3,4,5-trihydroxy-6-hydroxymethyl-tetrahydropyran-2-yloxy)-phenylcarbamoyl]-ethyl}-carbamic acid tert-butyl ester
C33H47N3O10
MW: 645.7 DaInternal Standard(6-D5-Benzoylamino-hexyl)-[2-(4-hydroxy-phenyl-carbamoyl)-ethyl]-carbamic
acid tert-butyl ester
C27H32N3O5D5
MW: 488.5 Da

Glucocerebrosidase Substrate and Internal Standard Mix (NSK-GA-1)
Each vial contains the following compounds at a molar ratio of 50:1.
Substrate
D-Glucosyl-β1-1‘-N-dodecanoyl-D-erythro-sphingosine[C12-glucocerebroside]
C36H69NO8
MW: 643.9 DaInternal Standard
N-Myristoyl-D-erythro-sphingosine [C14-ceramide]
C32H63NO3

MW: 509.8 Da

Galactocerebrosidase Substrate and Internal Standard Mix (NSK-KR-1)
Each vial contains the following compounds at a molar ratio of 150:1.
Substrate
D-Galactosyl-β1-1’-octanoyl-D-erythro-sphingosine [C8-galactosylceramide]
C32H61NO8
MW: 587.8 DaInternal Standard
N-Decanoyl-D-erythro-sphingosine [C10-ceramide]
C28H55NO3
MW: 453.7 Da

α-L-Iduronidase Substrate and Internal Standard Mix (NSK-MP-1)
Each vial contains the following compounds at a molar ratio of 150:1.
Substrate(7-(1-Iduronic acid)-oxycoumarin-4-methylamine-(5’-N-boc-aminopentanoyl)amide)
C26H34N2O12
MW: 566.6 DaInternal Standard(7-Hydroxycoumarin-4-methylamine-(4’-N-boc-aminobutanoyl)-amide)
C19H24N2O6

MW: 376.4 Da

Chemical purity (CP) is 98% or greater, unless otherwise specified.

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| MS/MS Screening Mixtures and Standards

Cambridge Isotope Laboratories, Inc.

Additional Standard Mixtures for Screening (continued)
Acid Sphingomyelinase Substrate and Internal Standard Mix (NSK-NI-1)
Each vial contains the following compounds at a molar ratio of 50:1.
Substrate
N-Hexanoyl-D-erythro-sphingosylphosphorylcholine [C6-sphingomyelin]
C29H59N2O6P
MW: 562.8 DaInternal Standard
N-Butyroyl-D-erythro-sphingosine [C4-ceramide]
C22H43NO3
MW: 369.6 Da

Acid α-Glucosidase Substrate and Internal Standard Mix (NSK-PO-1)
Each vial contains the following compounds at a molar ratio of 100:1.
Substrate(7-Benzoylamino-heptyl)-{2-[4-(3,4,5-trihydroxy-6-hydroxymethyl-tetrahydropyran-2-yloxy)-phenylcarbamoyl]-ethyl}-carbamic acid tert-butyl ester
C34H49N3O10
MW: 659.8 DaInternal Standard(7-D5-Benzoylamino-heptyl)-[2-(4-hydroxy-phenyl-carbamoyl)-ethyl]-carbamic
acid tert-butyl ester
C28H34N3O5D5
MW: 502.7 Da

Usage Specifications
Criteria
Use

Recommendation~600 samples/vial

Before reconstitution:
Storage-20°; protect from light
Recommended retest
2 years from date of manufacture

After reconstitution:
Storage
Recommended retest

5±3ºC or -20±5ºC
4 weeks

Example References
Ribas, G.; De Mari, J.F.; Civallero, G.; et al. 2017. Validation of a multiplex tandem mass spectrometry method for the detection of selected lysosomal storage diseases in dried blood
spots. JIMES, 5, 1-7.
Tortorelli, S.; Turgeon, C.T.; Gavrilov, D.K.; et al. 2016. Simultaneous testing for 6 lysosomal storage disorders and x-adrenoleukodystrophy in dried blood spots by tandem mass
spectrometry. Clin Chem, 62(9), 1248-1254.
Cho, S.E.; Kwak, J.R.; Lee, H.; et al. 2016. Triplex tandem mass spectrometry assays for the screening of 3 lysosomal storage disorders in a Korean population. Clin Chim Acta, 454,
20-27.

Chemical purity (CP) is 98% or greater, unless otherwise specified.

10

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| MS/MS Screening Mixtures and Standards

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Succinylacetone Reference Standard (NSK-T)
This set contains 10 vials of dried-down stable isotope-labeled succinylacetone. Accurate and complete reconstitution of one vial’s contents
in 1 mL of high-purity solvent will produce the concentrations listed in the table below. Individual vials are also available.
Example Reconstitution Approach for Concentrated Stock•	Solubilize the dried-down mix in 1 mL of highly pure methanol.
•	Vortex manually for 1 minute then auto-vortex for 30 minutes or until complete reconstitution is achieved.
Aliquots of the concentrated stock can then be processed, diluted, and /or stored as indicated below.
Example Dilution Approach for Working StockTo prepare working stock solutions, dilute 1 mL (or an aliqout) of the reconstituted vial contents (per instructions above) with pure solvent.
Composition
Standard (Abbreviation)
Succinylacetone (SUAC)

Usage Specifications
Label and Enrichment
3,4,5,6,7-13C5, 99%

MW (Da)163.12

Conc. (µM)
1000

Note: One vial of the unlabeled succinylacetone standard (NSK-T-US) is also available,
having an unlabeled SUAC concentration of 0.1 mg/mL.

Criteria
Recommendation
Use
9,600 samples/vial
Before reconstitution:
Storage≤25ºC; protect from light andmoisture
Recommended retest
5 years from date of manufacture
After reconstitution:
Storage
Store in a tightly sealed vial at
5±3ºC. To maintain the integrity ofthe solution, store the sealed vials
in a second sealed container.
Recommended retest
4 weeks

Example References
Fuenzalida, K.; Leal-Witt, M.J.; Guerrero, P.; et al. 2021. NTBC treatment monitoring in Chilean patients with tyrosinemia type 1 and its association with biochemical parameters andliver biomarkers. J Clin Med, 10(24), 5832-5845.
Schupper, A.; Almashanu, S.; Coster, D.; et al. 2021. Metabolic biomarkers of small and large for gestational age newborns. Early Hum Dev, 160, 105422-105429.
Staretz-Chacham, O.; Daas, S.; Ulanovsky, I.; et al. 2021. The role of orotic acid measurement in routine newborn screening for urea cycle disorders. J Inherit Metab Dis, 44(3),606-617.
Brennenstuhl, H.; Kohlmüller, D.; Gramer, G.; et al. 2020. High throughput newborn screening for aromatic ι-amino-acid decarboxylase deficiency by analysis of concentrations of
3-O-methyldopa from dried blood spots. J Inherit Metab Dis, 43(3), 602-610.
Jack, R.M.; Scott, C.R. 2019. Validation of a therapeutic range for nitisinone in patients treated for tyrosinemia type 1 based on reduction of succinylacetone excretion.
JIMD Reports, 46(1), 75-78.
Céspedes, N.; Valencia, A.; Echeverry, C.A.; et al. 2017. Reference values of amino acids, acylcarnitines and succinylacetone by tandem mass spectrometry for use in newborn
screening in southwest Colombia. Colomb Med (Cali), 48(3), 113-119.
de Sain-van der Velden, M.G.M.; van der Ham, M.; Gerrits, J.; et al. 2017. Quantification of metabolites in dried blood spots by direct infusion high resolution mass spectrometry.
Anal Chim Acta, 979, 45-50.
Haynes, C.A.; De Jesús, V.R. 2016. Simultaneous quantitation of hexacosanoyl lysophosphatidylcholine, amino acids, acylcarnitines, and succinylacetone during FIA-ESI-MS/MS
analysis of dried blood spot extracts for newborn screening. Clin Biochem, 49(1-2), 161-165.
Pankowicz, F.P.; Barzi, M.; Legras, X.; et al. 2016. Reprogramming metabolic pathways in vivo with CRISPR /Cas9 genome editing to treat hereditary tyrosinaemia. Nat Commun,
7, 12642-12647.
Technical Note
Xie, X.; Kozak, M. 2020. Simultaneous analysis of amino acids, acylcarnitines, and succinylacetone in dried blood spots for research using nonderivatized and derivatized methods.
(Thermo Scientific technical note #73398).

Chemical purity (CP) is 98% or greater, unless otherwise specified.

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| MS/MS Screening Mixtures and Standards

Cambridge Isotope Laboratories, Inc.

Additional Example Standards for Screening
Catalog No.
CLM-3777
CLM-3678
CLM-8906
CNLM-3946
DLM-10008
CNLM-9007
DLM-9276
DLM-9067
DLM-6718
DLM-7347
DLM-9976
CLM-7933
DLM-1302
DLM-3653
CLM-10549
DLM-8049
CLM-10784
DLM-8337
CLM-4579
DLM-7687
DLM-3023
CLM-7824
DLM-2084
CLM-803
DLM-2487
CLM-9148
DLM-3976
DLM-6013
CLM-1570
CLM-9874
CLM-1822-H
DLM-1826
CLM-1017
DLM-280
CNLM-8111
DLM-9715
DLM-9998
DLM-7689
CNLM-8448
CLM-373
DLM-2738
DLM-8118
CLM-9936
DLM-7206
DLM-3619
NLM-4264
CLM-8742
DLM-1505
CNLM-9291
CLM-2247-H

Standard
N-Acetylglycine
Adenosine
S-Adenosyl-L-homocysteineβ-Alanine5-Androstan-3α-ol-17-one (etiocholanolone)
L-Argininosuccinic acid, barium salt·2H2O
O-Hexanoyl-L-carnitine·HCl
O-Decanoyl-L-carnitine·HCl
O-Hexacosanoyl-L-carnitine·HCl
Corticosterone
Cortisone
Creatine
Creatine
Creatinine
Dehydroepiandrosterone
Dehydroepiandrosterone
Dehydroepiandrosterone sulfate·sodium salt
Dehydroepiandrosterone sulfate sodium
salt·2H2O
2’-Deoxyadenosine·H2O
2’-Deoxyguanosine·H2O
Dihydrotestosterone
L-Dihydroxyphenylalanine
L-Dihydroxyphenylalanine
Estradiol
Estradiol
EstroneEstroneEthylmalonic acid
D-Galactose
D-Galactose-1-phosphate, dipotassium salt
L-Glutamine
L-Glutamine
GlycineGlycineN-(3-Methylcrotonyl)glycine
N-(3-Phenylpropionyl)glycine
Guanidinoacetic acid
Guanosine·H2O
N-Hexanoylglycine
Homovanillic acid
Homovanillic acid
3-Hydroxyglutaric acid
5-Hydroxyindole-3-acetic acid
17α-Hydroxypregnenolone
DL-Homocystine
InosineL-allo-Isoleucine
L-allo-Isoleucine
N-Isovalerylglycine
L-Lysine·2HCl

Abbreviation
AG
Ado
SAH
BALA
etio

Label and Enrichment
2-13C, 99%
ribose-13C5, 98% (CP 97%)
adenosine-13C10, 98% (CP 95%)
13
C3, 98%; 15N, 96-99%
2,2,3,4,4-D5, 98%

Unit Size
Please inquire
0.05 g, 0.1 g
0.1 mg0.25 g
1 mg

ASA
C6
C10
C26
B
E
Cre
Cre
Crn
DHEA
DHEA
DHEAS
DHEAS

arginine-13C6, 99%; 15N4, 99% (CP 90%)
N-methyl-D3, 98%
N-methyl-D3, 98%
N-methyl-D3, 98% (CP 95%)
2,2,4,6,6,17α,21,21-D8, 97-98%
2,2,4,6,6,9,12,12-D8, 98%
guanidino-13C, 99%
methyl-D3, 98% (CP 97%)
N-methyl-D3, 98%
2,3,4-13C3, 99%
2,2,3,4,4,6-D6, 98% (CP 97%)
2,3,4-13C3, 98%
2,2,3,4,4,6-D6, 95%

0.1 mg, 0.5 mg
0.1 mg
0.1 mgPlease inquire
0.01 g
1 mg, 5 mg
0.1 g
0.25 g
0.1 g
1 mg
5 mg
1 mg
5 mg

dAdo
2dG
DHT
L-Dopa
L-Dopa
E2
E2
E1
E1
EMA
Gal
Gal-1P
Gln
Gln
Gly
Gly
3-MCG
3-PPG
GAA
Guo
HG
HVA
HVA
3-OHGA
5-HIAA
17-OHP5
HCY
Ino
alle
alle
IVG
Lys

ribose-13C5, 99%
ribose-5,5-D2, 98%
16,16,17-D3, 98%
1-13C, ring-13C6, 99%
ring-D3, 98%
3,4-13C2, 99%
2,4,16,16-D4, 95-97%
2,3,4-13C3, 99%
2,4,16,16-D4, 97%
methyl-D3, 98%
U-13C6, 99%
galactose-13C6, 99%
13
C5, 99%2,3,3,4,4-D5, 97%
13
C2, 97-99%
D5, 98%glycine-13C2, 98%; 15N, 98%
2,2,-D2, 98%
2,2-D2, 97%
ribose-5,5-D2, 98%
13
C2, 97-99%; 15N, 97-99% (CP 95%)
1,2-13C2, 98-99%
phenyl-D3, 2,2-D2, 96-98%
D5, 98%(3α,4,5,6,7,7α-13C6, 98%)
21,21,21-D3, 97%
3,3,3’,3’,4,4,4’,4’-D8, 98%
15
N4, 95%13
C6, 97-99%
D10, 98%
glycine-13C2, 99%; 15N, 99%
13
C6, 99%Please inquire
0.05 g, 0.1 g
Please inquire
0.05 g
1g
Please inquire
5 mg
1 mg, 5 mg
5 mg
0.1 g
0.1 g
Please inquire
0.1 g, 0.25 g, 0.5 g
0.1 g
0.5 g, 1 g, 5 g
5g
Please inquire
Please inquire
Please inquire
Please inquire
Please inquire
0.1 g
0.1 g
Please inquire
1.2 mL
Please inquire
0.5 g, 1 g
0.01 g, 0.05 g
Please inquire
0.1 g
Please inquire
0.05 g, 0.1 g, 0.25 g,
0.5 g, 1 g

Chemical purity (CP) is 98% or greater, unless otherwise specified.

12

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| MS/MS Screening Mixtures and Standards

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Additional Example Standards for Screening (continued)
Catalog No.
DLM-10520
CLM-10499
DLM-10500
CLM-10496
DLM-10497
CLM-9792
DLM-10501
DLM-205
DLM-11341
CLM-10350
DLM-2312
CLM-9426
DLM-387
CLM-4724
DLM-2969
NLM-1048
DLM-7953
DLM-6896
CLM-2260-H
DLM-487
CLM-7944
CLM-647
DLM-1919
CNLM-9292
DLM-6874
CNLM-8183
CLM-9164
DLM-8085
CLM-6725
CLM-8931
DLM-10758
CLM-4290-H
DLM-6903
ULM-11135

Standard
Lysophosphatidylcholine 20:0
Lysophosphatidylcholine 22:0
Lysophosphatidylcholine 22:0
Lysophosphatidylcholine 24:0
Lysophosphatidylcholine 24:0
Lysophosphatidylcholine 26:0
Lysophosphatidylcholine 26:0
Malonic acid
L-3-O-Methyl-dopa·H2O
2-Methylbutyric acidDL-2-Methylcitric acid
Methylmalonic acid
Methylmalonic acid
L-Ornithine·HCl
L-Ornithine·HCl
Orotic acid·H2O
Progesterone
Pregnenolone
L-Proline
L-Proline
3-(3-Methyl-1H-pyrazol-5-yl)propanoic acid
Propionic acid
Propionic acid
N-Propionylglycine
Sarcosine·HCl (N-methylglycine·HCL)
Suberylglycine
Testosterone
Testosterone
L-Thyroxine
L-Thyroxine
Trisodium 2-methylcitrate, racemic mixtureof diastereomers
L-Tryptophan
L-Tryptophan
Uridine diphosphate-α-N-acetyl-Dglucosamine, disodium salt

Abbreviation
LysoPC C20:0
LysoPC C22:0
LysoPC C22:0
LysoPC C24:0
LysoPC C24:0
LysoPC C26:0
LysoPC C26:0
MA
3-OMD
2-MBA
MCA
MMA
MMA
Orn
Orn
Oro
P4
P5
Pro
Pro
MPP
PPA
PPA
PG
Sar
SG
T
T
T4
T4
MCA

Label and Enrichment
eicosanoyl-12,12,13,13-D4, 98%
docosanoyl-1,2,3,4,5,6-13C6, 99%
docosanoyl-12,12,13,13-D4, 98%
tetracosanoyl-1,2,3,4,5,6-13C6, 99%
tetracosanoyl-12,12,13,13-D4, 98%
hexacosanoyl-1,2,3,4,5,6-13C6, 99%
hexacosanoyl-12,12,13,13-D4, 98%
D4, 98%methoxy-D3, 98%
methyl-13C, 99%
methyl-D3, 98% (CP 90%)13
C4, 99%methyl-D3, 98%
13
C5, 99%3,3,4,4,5,5-D6, 98%
1,3-15N2, 98%
2,2,4,6,6,17α,21,21,21-D9, 98%
17,21,21,21-D4, 98%
13
C5, 99%D7, 97-98%
methyl-13C, pyrazolyl-13C3, 3-13C, 99%
13
C3, 99%D5, 98%glycine-13C2, 99%; 15N, 99%
methyl-D3, 98%
glycine-13C2, 98%; 15N, 98% (CP 95%)
2,3,4-13C3,99%
2,2,4,6,6-D5, 98%
tyrosine-ring-13C6, 99% (CP 90%)ring-13C12, 99% (CP 97%)
methyl-D3, 98% (CP 90%)

Unit Size
1 mg, 5 mg
1 mg, 5 mg
1 mg, 5 mg
1 mg, 5 mg
1 mg, 5 mg
1 mg, 5 mg
1 mg, 5 mg
50 g
Please inquire
Please inquire
Please inquire
0.1 g
0.25 g
0.1 g
0.1 g, 0.25 g
0.25 g0.01 g0.01 g
0.1 g, 0.25 g, 0.5 g
0.1 g, 0.25 g
Please inquire
1g
5g
Please inquire
0.1 g, 0.25 g
Please inquire
5 mg, 10 mg
Please inquire
0.1 mg
0.1 mg5 mg, 10 mg

Trp
Trp
UDP-GlcNAc

13

C11, 99%
D8, 97-98%
unlabeled

0.1 g
0.25 gPlease inquireNote: Unlabeled standards are also available. Please inquire for size and pricing or visit isotope.com.
Example References
Daas, S.; Salah, N.A.; Anikster, Y.; et al. 2023. Addition of galactose-1-phosphate measurement enhances newborn screening for classical galactosemia. J Inherit Metab Dis, 46(2),232-242.
Young, A.; Hendricks, J.; Foreman, D.; et al. 2020. Development of dried blood spot quality control materials for adenosine deaminase severe combined immunodeficiency and an
LC-MS/MS method for their characterization. Clin Mass Spec, 17, 4-11.
Coene, K.L.M.; Kluijtmans, L.A.J.; van der Heeft, E.; et al. 2018. Next-generation metabolic screening: targeted and untargeted metabolomics for the diagnosis of inborn errorsof metabolism in individual patients. J Inherit Metab Dis, 41(3), 337-353.
Monostori, P.; Klinke, G.; Richter, S.; et al. 2017. Simultaneous determination of 3-hydroxypropionic acid, methylmalonic acid and methylcitric acid in dried blood spots:
Second-tier LC-MS/MS assay for newborn screening of propionic acidemia, methylmalonic acidemias and combined remethylation disorders. PLoS One, 12(9), e0184897.
Nakano, M.; Uemura, O.; Honda, M.; et al. 2017. Development of tandem mass spectrometry-based creatinine measurement using dried blood spot for newborn mass screening.
Pediatr Res, 82(2), 237-243.
Prinsen, H.C.M.T.; Schiebergen-Bronkhorst, B.G.M.; Roeleveld, M.W.; et al. 2016. Rapid quantification of underivatized amino acids in plasma by hydrophilic interaction
liquid chromatography (HILIC) coupled with tandem mass-spectrometry. J Inherit Metab Dis, 39(5), 651-660.
Held, P.K.; Haynes, C.A.; De Jesús, V.R.; et al. 2014. Development of an assay to simultaneously measure orotic acid, amino acids, and acylcarnitines in dried blood spots.
Clin Chem Acta, 436, 149-154.

Chemical purity (CP) is 98% or greater, unless otherwise specified.

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| MS/MS Screening Mixtures and Standards

Cambridge Isotope Laboratories, Inc.

MS/MS Parameter Examples
Neutral Loss (NL) Scan (for NSK-A and NSK-A1 Standards)
CompoundAbbreviation

Alanine (D4)(all m/z as [M+H]+)

Underivatized

Butyl Ester DerivatizedPrecursor Ion m/z

NL m/zPrecursor Ion m/z

NL m/z

Ala

94

46

150

102

Arginine (13C/D4)

Arg

180

105

236

161

Aspartate (D3)

Asp

137

46

249

102

Citrulline (D2)

Cit

178

63

234

119

Glutamate (D3)

Glu

151

46

263

102

Glycine (13C/ 15N)

Gly

78

46

134

102

Leucine (D3)

Leu

135

46

191

102

Methionine (D3)

Met

153

46

209

102

Ornithine (D2)

Orn

135

63

191

119

Ornithine (D6)

Orn

139

63

195

119

Phenylalanine ( C6)

Phe

172

46

228

102

Tyrosine (13C6)

Tyr

188

46

244

102

Valine (D8)

Val

126

46

182

102

13

Note: The MS/MS fragmentation mechanism of amino acids during NL scan is well established (e.g., PMID: 14578311). For example, the losses for theunderivatized amino acids reflect HCOOH (m/z 46), HCOOH and NH3 (m/z 63), and HCOOH and H2NCNHNH2 (m/z 105).

Precursor (Pre) Ion Scan (for NSK-B and NSK-B-G1 Standards)
CompoundAbbreviation

Carnitine (D9)(all m/z as [M+H]+)

Underivatized

Butyl Ester DerivatizedPrecursor Ion m/z

Product Ion m/z

Precursor Ion m/z

Product Ion m/z

C0

171

85

227

85

Acetylcarnitine (D3)

C2

207

85

263

85

Propionylcarnitine (D3)

C3

221

85

277

85

Butyrylcarnitine (D3)

C4

235

85

291

85

Isovalerylcarnitine (D9)

C5

255

85

311

85

Glutarylcarnitine (D3)

C5-DC

279

85

391

85

Hydroxyisovalerylcarnitine (D3)

C5-OH

265

85

321

85

Octanoylcarnitine (D3)

C8

291

85

347

85

Dodecanoylcarnitine (D9)

C12

353

85

409

85

Myristoylcarnitine (D9)

C14

381

85

437

85

Palmitoylcarnitine (D3)

C16

403

85

459

85

C16-OH

419

85

475

85

C18

431

85

487

85

Hydroxypalmitoylcarnitine (D3)Octadecanoylcarnitine (D3)

Note: The common fragment ion of m/z 85 corresponds to +CH2-CH=CH-COOH and is consistent between nonderivatized and derivatized acylcarnitines(e.g., PMID: 9365395 for background and fragmentation mechanism).

Chemical purity (CP) is 98% or greater, unless otherwise specified.

14

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| MS/MS Screening Mixtures and Standards

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MS/MS Parameter Examples (continued)
MRM Acquisition Mode (for NSK-A, NSK-A1, and NSK-T Standards)
CompoundAbbreviation

Alanine (D4)(all m/z as [M+H]+)

Underivatized

Butyl Ester DerivatizedPrecursor Ion m/z

Product Ion m/z

Precursor Ion m/z

Product Ion m/z

Ala

94

48

150

48

Arginine ( C/D4)

Arg

180

75

236

75

Aspartate (D3)

Asp

137

119

249

147

Citrulline (D2)

Cit

178

115

234

115

Glutamate (D3)

Glu

151

133

263

161
78

13

Glycine ( C/ N)

Gly

78

32

134

Leucine (D3)

Leu

135

89

191

89

Methionine (D3)

Met

153

136

209

107

Ornithine (D2)

Orn

135

72

191

72

Ornithine (D6)

Orn

131

68

195

68

Phenylalanine (13C6)

Phe

172

126

228

126

Tyrosine (13C6)

Tyr

188

142

244

142

Valine (D8)

Val

126

80

182

80

SUAC

160

114

216

142

13

15

Succinylacetone ( C5)13

MRM Acquisition Mode (for NSK-B and NSK-B-G1 Standards)
CompoundAbbreviation

Carnitine (D9)(all m/z as [M+H]+)

Underivatized

Butyl Ester DerivatizedPrecursor Ion m/z

Product Ion m/z

Precursor Ion m/z

Product Ion m/z

C0

171

103

227

103

Acetylcarnitine (D3)

C2

207

85

263

85

Propionylcarnitine (D3)

C3

221

85

277

85

Butyrylcarnitine (D3)

C4

235

85

291

85

Isovalerylcarnitine (D9)

C5

255

85

311

85

Glutarylcarnitine (D3)

C5-DC

279

85

335

85

Hydroxyisovalerylcarnitine (D3)

C5-OH

265

85

321

85

Octanoylcarnitine (D3)

C8

291

85

347

85

Dodecanoylcarnitine (D9)

C12

353

85

409

85

Myristoylcarnitine (D9)

C14

381

85

437

85

Palmitoylcarnitine (D3)Hydroxypalmitoylcarnitine (D3)Octadecanoylcarnitine (D3)

C16

403

85

459

85

C16-OH

419

85

475

85

C18

431

85

487

85

Technical Note
Xie, X.; Kozak, M. 2020. Simultaneous analysis of amino acids, acylcarnitines, and succinylacetone in dried blood spots for research using nonderivatized and derivatized methods.
Thermo Fisher Scientific, San Jose, CA.

Chemical purity (CP) is 98% or greater, unless otherwise specified.

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| MS/MS Screening Mixtures and Standards

Cambridge Isotope Laboratories, Inc.

MS/MS Parameter Examples (continued)
MRM Acquisition Mode (for NSK-AA3 Standards)

(all m/z as [M+H]+)

CompoundCreatine (D5)
Guanidinoacetic acid (13C2 / 15N)
L-Proline (D7)

Product Ion m/z
95
79
77

Abbreviation
Cre
GAA
Pro

Precursor Ion m/z
137
121
123

MRM Acquisition Mode (for NSK-BCAA Standards)

(all m/z as [M+H]+)

Compound
L-Allo-isoleucine (13C6/ 15N)
L-Isoleucine (D10)
L-Leucine (D3)
L-Valine (13C5/ 15N)

Product Ion m/z
92
96
89
77

Abbreviation
Alle
Ile
Leu
Val

Precursor Ion m/z
139
142
135
124

MRM Acquisition Mode (for NSK-S and NSK-S-EXP Standards)(all m/z as [M+H]+ unless otherwise specified)CompoundAldosterone (D7)4-Androstene-3,17-dione (D5)Corticosterone (D8)Cortisol (D3)11-Deoxycortisol (D5)21-Deoxycortisol (D8)17α-Hydroxyprogesterone (D8)Progesterone (D9)Testosterone (D5)Abbreviation
A
A4
B
F
11-S
21-S
17-OHP
P
T

Precursor Ion m/z
350 for [M+H+-H2O]+
292
355
366
352
355
339
324
294

Product Ion m/z
173
100
125
121
100
319
100
100
100

MRM Acquisition Mode (for NSK-LPC Standards)

(all m/z as [M+H]+)

CompoundLysophosphatidylcholine 20:0 (D4)
Lysophosphatidylcholine 22:0 (13C6)
Lysophosphatidylcholine 24:0 (13C6)
Lysophosphatidylcholine 26:0 (13C6)

Product Ion m/z
104
104
104
104

Abbreviation
LPC 20:0
LPC 22:0
LPC 24:0
LPC 26:0

Precursor Ion m/z
556
586
614
643

Chemical purity (CP) is 98% or greater, unless otherwise specified.

16

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| MS/MS Screening Mixtures and Standards

Cambridge Isotope Laboratories, Inc.

Please visit isotope.com for a complete list of isotope-labeled compounds.
Research products are distributed and sold worldwide via our extensive network.
To request a quotation or place an order:
North America: 1.978.749.8000 | 1.800.322.1174 | cilsales@isotope.com
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CIL’s distributor listing is available at isotope.com.

Setting the Standard…
Donald H. Chace, PhD MSFS FACB
Medolac Laboratories❝ In clinical chemistry-based applications of mass spectrometry, the first lesson the laboratory learns is the requisite nature ofstable isotope-enriched standards for quantification of metabolites in biological fluids. In newborn screening of amino acids
and acylcarnitines, Cambridge Isotope Laboratories, Inc., set the standard for quantification of these metabolites in dried
blood spots. As research and development of the newborn screening analysis by mass spectrometry progressed, it was clearthat a half dozen isotope-labeled internal standards would not be adequate for the analysis of an amino acid and acylcarnitine
profile, together comprising a range of 500 separate mass units and more than 30 important metabolites, most of which require
accurate quantification. When screening began to expand beyond research, it was clear that weighing out small quantities ofindividual standards would reduce accuracy and introduce unnecessary error. Therefore, together, we set out to develop setsof standards for amino acids and acylcarnitine analysis that would enable quantification. We started this development morethan 20 years ago adding, changing and improving these standards. CIL, together with the early developers of tandem mass
spectrometry-based newborn screening, set the standard by which all other laboratories follow. CIL’s commitment to supporting
the metabolic and newborn screening community is exceptional. It is our good fortune in the clinical chemistry and mass
spectrometry community to have CIL as part of our laboratory solutions.❞

For research use only. Not for use in diagnostic procedures.
The references in this document were chosen to represent the wide range of applications that CIL products support. Papers not referenced in this document do not imply a lesser
impact on the scientific community.
These articles do not imply that materials produced by CIL are suitable for any intended purpose.

Cambridge Isotope Laboratories, Inc. 3 Highwood Drive, Tewksbury, MA 01876 USA
North America: 1.800.322.1174 | International: +1.978.749.8000 | fax: +1.978.749.2768 | isotope.com

MSMS_STANDARDS (5/16/23)

Supersedes all previously published literature