The isotope-labelled auxins are very useful tools for studying biosynthesis and metabolism of auxins but also for determination of endogenous auxin levels by mass spectrometry (MS). The sensitivity and accuracy of this technique can be increased enormously with introduction of the use of an internal standard such as deuterium-labelled IAA. 2,4,5,6,7-Deuterium labelled as well as ¹³C labelled IAA can be used in these MS measurements.

[²H₅]INDOLE-3-ACETIC ACID (D-IAA) [3-[²H₅]indolylacetic acid]

MW 180.22; CRYSTALLINE; purity > 97% (HPLC)
S:26, 36; CAS: 76937-78-5; C10H42H5NO2
	031 1531	5	mg
	031 1532	10	mg
	031 1533	50	mg

[¹³C₆]INDOLE-3-ACETIC ACID (13C-IAA) [3-[¹³C₆]indolylacetic acid]

MW 181.12; CRYSTALLINE; purity > 97% (HPLC)
S:26, 36; CAS: NONE; 13C6C4H9NO2
	031 7331	1	mg
	031 7332	2	mg
	031 7333	5	mg

[²H₅]INDOLE-3-[¹⁵N] ACETAMIDE (DN-IAm)

MW 180.23; N2 EVAPORATE; purity > 95% (HPLC)
S:26, 36; CAS: 1204700-53-7; C10H52H5N15NO
	031 1541	50	µg
	031 1542	100	µg
	031 1543	250	µg

[²H₅]INDOLE-3-ACETIC ACID METHYL ESTER (D-IAAMe) [methyl [²H₅]indole-3-acetate]

MW 194.25; CRYSTALLINE; purity > 98% (HPLC)
S:26, 36; CAS: 102415-39-4; C11H62H5NO2
	031 1551	5	mg
	031 1552	10	mg
	031 1553	50	mg

[²H₄]INDOLE-3-ACETONITRILE (D-IAN)

MW 160.21; N2 EVAPORATE; purity > 95% (HPLC)
R:20/21/22, S:36/37; CAS: 1204700-51-5; C10H42H4N2
	031 1851	50	µg
	031 1852	100	µg
	031 1853	250	µg

[²H₅]INDOLE-3-ACETYL-L-[¹⁵N] ALANINE (DN-IAAla) [N-(3-[²H₅] indolylacetyl)-L-[¹⁵N] alanine]

MW 252.29; N2 EVAPORATE; purity > 95% (HPLC)
S:26, 36; CAS: 1201012-70-5; C13H92H5N15NO3
	031 1581	50	µg
	031 1582	100	µg
	031 1583	250	µg

[²H₅]INDOLE-3-ACETYL-L-[¹⁵N] ASPARTIC ACID (DN-IAAsp) [N-(3-[²H₅] indolylacetyl)-L-[¹⁵N] aspartic acid]

MW 296.30; N2 EVAPORATE; purity > 95% (HPLC)
S:26, 36; CAS: 1201012-71-6; C14H92H5N15NO5
	031 1591	50	µg
	031 1592	100	µg
	031 1593	250	µg

[¹³C₆]INDOLE-3-ACETYL-L-[¹⁵N] ASPARTIC ACID (CN-IAAsp) [N-(3-[¹³C₆] indolylacetyl)-L-[¹⁵N] aspartic acid]

MW 297.20; N2 EVAPORATE; purity > 95% (HPLC)
S:26, 36; CAS: NONE; 13C6C8H14N15NO5
	031 7341	50	µg
	031 7342	100	µg
	031 7343	250	µg

[²H₅]INDOLE-3-ACETYL-L-[¹⁵N] GLUTAMIC ACID (DN-IAGlu) [N-(3-[²H₅] indolylacetyl)-L-[¹⁵N] glutamic acid]

MW 310.33; N2 EVAPORATE; purity > 95% (HPLC)
S:26, 36; CAS: 1201012-72-7; C15H112H5N15NO5
	031 6131	50	µg
	031 6132	100	µg
	031 6133	250	µg

[¹³C₆]INDOLE-3-ACETYL-L-[¹⁵N] GLUTAMIC ACID (CN-IAGlu) [N-(3-[¹³C₆] indolylacetyl)-L-[¹⁵N] glutamic acid]

MW 311.23; N2 EVAPORATE; purity > 95% (HPLC)
S:26, 36; CAS: NONE; 13C6C9H16N15NO5
	031 7351	50	µg
	031 7352	100	µg
	031 7353	250	µg

[²H₅]INDOLE-3-ACETYL-L-[¹⁵N] ISOLEUCINE (DN-IAIleu) [N-(3-[²H₅] indolylacetyl)-L-[¹⁵N] isoleucine]

MW 294.37; N2 EVAPORATE; purity > 95% (HPLC)
S:26, 36; CAS: NONE; C16H152H5N15NO3
	031 1601	50	µg
	031 1602	100	µg
	031 1603	250	µg

[²H₅]INDOLE-3-ACETYL-L-[¹⁵N] LEUCINE (DN-IALeu) [N-(3-[²H₅] indolylacetyl)-L-[¹⁵N] leucine]

MW 294.37; N2 EVAPORATE; purity > 95% (HPLC)
S:26, 36; CAS: 1201012-74-9; C16H152H5N15NO3
	031 1611	50	µg
	031 1612	100	µg
	031 1613	250	µg

[²H₅]INDOLE-3-ACETYL-L-[¹⁵N] PHENYLALANINE (DN-IAPhe) [N-(3-[²H₅] indolylacetyl)-L-[¹⁵N] phenylalanine]

MW 328.39; N2 EVAPORATE; purity > 95% (HPLC)
S:26, 36; CAS: 1201012-75-0; C16H132H5N15NO3
	031 1621	50	µg
	031 1622	100	µg
	031 1623	250	µg

[²H₅]INDOLE-3-ACETYL-L-[¹⁵N] TRYPTOPHAN (DN-IATrp) [N-(3-[²H₅] indolylacetyl)-L-[¹⁵N] tryptophan]

MW 366.44; N2 EVAPORATE; purity > 95% (HPLC)
S:26, 36; CAS: NONE; C21H142H5N3O3
	031 1631	50	µg
	031 1632	100	µg
	031 1633	250	µg

[²H₅]INDOLE-3-ACETYL-L-[¹⁵N] VALINE (DN-IAVal) [N-(3-[²H₅] indolylacetyl)-L-[¹⁵N] valine]

MW 280.35; N2 EVAPORATE; purity > 95% (HPLC)
S:26, 36; CAS: 1201012-76-1; C15H182H5N15NO3
	031 1641	50	µg
	031 1642	100	µg
	031 1643	250	µg

[²H₅]INDOLE-3-ACETALDOXIME (DN-IAOx) E/Z mixture

MW 179.16; N2 EVAPORATE; purity > 95% (HPLC)
S:26, 36; CAS: NONE; C10H52H5N2O
	031 6911	50	µg
	031 6912	100	µg
	031 6913	250	µg

[²H₅]TRYPTOPHOL (D-IEt)[3-(2-hydroxyethyl) [²H₅] indole, [²H₅] indole-3-ethanol]]

MW 166.24; N2 EVAPORATE; purity > 95% (HPLC)
S:26, 36; CAS: NONE; C10H62H5NO
	031 2291	50	µg
	031 2292	100	µg
	031 2293	250	µg