[2-(Trimethylammonium)ethyl] Methanethiosulfonate Bromide (MTSET Bromide) [91774-25-3]

Reacts specifically and rapidly with thiols to form mixed disulfides. Used to probe the structures of the ACh receptor channel of the GABAA receptor channel and of lactose permease.

At pH 7.5 and room temperature, MTSEA hydrolyzes with a half-life of about 15 minutes, MTSET hydrolyzes with a half-life of 10 minutes, and MTSES hydrolyzes with a half-life of 20 minutes. Routinely, one can use 2.5mM MTSEA, 1mM MTSET, or 10mM MTSES, applied for 1 to 5 minutes. (MTSET is 2.5 times as reactive with small sulfhydryl compounds as is MTSEA, and 10 times as reactive as MTSES). (Stauffer and Karlin, 1994; Karlin, personal communication).

For application to Xenopus Oocytes, dissolve the compounds in 115mM NaCl, 2.5mM KCl, 1.8mM MgCl2, 10mM Hepes, pH 7.5 with NaOH. MTS reagents decompose in buffer very quickly.

•DMSO is a good solvent for the MTS reagents which are not water soluble (i.e. the non-charged MTS reagents).

Synonyms:
N,N,N-Trimethyl-2-[(methylsulfonyl)thio]-ethanaminium Bromide; MTSET;
(2-Mercaptoethyl)trimethylammonium Bromide Methanesulfonate;
Methanethiosulfonate Ethyltrimethylammonium Bromide

CAS No:
91774-25-3

Molecular Formula:
C6H16BrNO2S2

Molecular Weight:
278.23

Purity:
≥95%

Appearance:
White solid

Solubility:
Methanol (Slightly), Water (Slightly)

Method for Determining Identity:
Proton NMR Spectroscopic and Mass Spectrometric Analysis

TLC Conditions:
C18; Water: Isppropanol: Acetic Acid=6:4:1; Visualized with AMCS and KMnO4; Single Spot, Rf=0.65

Melting Point:
151-158°C

Bromide:
As Reported

Elemental Analysis:
Calculated: %C: 25.90, %H: 5.80, %N: 5.03

Storage and Stability:
May be stored at RT for short-term only. Long-term storage is recommended at -20°C. Stable for 6 months after receipt under inert atmosphere.. For maximum recovery of product, centrifuge the original vial prior to removing the cap.