10
For more information, or to download product instructions,
Thermo Scientific Silylation Reagents
MTBSTFA and MTBSTFA + 1% TBDMCS
Offers stable TBDMS (tert-butyldimethylsilyl)
derivatization.
20
MTBSTFA
MW 241.3
bp 168-170
˚
C
d
4
1.121
C
CF
3
N
Si
C
CH
3
CH
3
O
CH
3
CH
3
CH
3
CH
3
CH
3
TBDMCS
MW 150.73
bp 125˚C
C Si
CI
CH
3
CH
3
CH
3
CH
3
Highlights:
• Derivatizes hydroxyl, carboxyl, thiol and primary and
secondary amines
• Typical yields are >96%
• Provides TBDMS ethers that are 104 times more stable
to hydrolysis than TMS ethers
• Reaction byproducts are neutral and volatile
• Derivatives have a high molecular concentration at M-57
• Silylating potential increased by adding 1% TBDMCS
Thermo Scientific
N
-Methyl-
N
-(
tert
-butyldimethylsilyl)-
trifluoroacetamide (MTBSTFA) provides TBDMS derivatives
without the disadvantage of earlier reported TBDMS-Cl
formulations. Bazan and Knapp have demonstrated the
usefulness of MTBSTFA by preparing an improved
derivative of 6-keto-prostaglandin F1 for GC-MS.
PROTOCOL
1. Combine 1-10 mg of sample, 0.1 ml MTBSTFA and 0.1 ml acetonitrile in a
1.0 ml Thermo Scientific Reacti-Vial Small Reaction Vial.
2. Cap vial and stand at room temperature 5-20 minutes.
3. Analyze by gas chromatography.
NOTE:
Other solvents may be used including DMF, pyridine and THF. (DMF is
not recommended for primary or secondary amines.)
Ordering Information
Product # Description
Pkg. Size
TS-48920
MTBSTFA
5 ml
[
N
-Methyl-
N
-(
tert
-butyldimethylsilyl)
Hypo-Vial Sample
trifluoroacetamide]
Storage Vial
TS-48927
MTBSTFA +1% TBDMCS
10 x 1 ml
ampules
TMSI
The strongest hydroxyl silylator available for carbohydrates
and steroids.
20
TMSI
MW 140.26
bp 99
˚
C/14 mm Hg
d
4
0.957
N
Si
CH
3
CH
3
CH
3
N
Sakauchi and Horning have shown TMSI to be an all-purpose
reagent for unhindered steroids to highly hindered steroids.
Thermo Scientific TMSI is unique, as it reacts quickly and
smoothly with hydroxyls and carboxylic acids, but not with
amines. Because TMS-derivatives are less stable than
TMS-ethers or -esters, TMSI is especially useful in multide-
rivatization schemes for compounds containing both hydroxyl
and amine groups (such as in the preparation of -O-TMS,
-N-HFB derivatives of catecholamines).
TMSI is used in the derivatization of alcohols, phenols,
organic acids steroids hormones glycols, nucleotides and
narcotics. In addition, it is excellent for C1 through C5 fatty
acids in serum and urine.
PROTOCOL 1
This method combines silylation of hydroxyl groups and acylation of
amino groups. It was first used by M.G. Horning,
et al.
to prepare
catecholamines for GC and GC/MS determinations.This method takes
advantage of the fact that TMSI will silylate only hydroxyl groups.
Effectively, this blocks those sites from acylation while leaving the
amine sites open for acylation.
1. Combine and dissolve 1.0 mg sample and 1.0 ml acetonitrile in a 1.0 ml
Thermo Scientific Reacti-Vial Small Reaction Vial.
2. Add 0.2 ml TMSI.
3. Cap vial and heat at 60°C for 3 hours.
4. Add 0.1 ml HFBI, TFAI or PFPI (depending on which acyl derivative is
desired).
5. Cap vial and heat at 60°C for 30 minutes.
6. Analyze by gas chromatography.
PROTOCOL 2
This method was developed by Sakauchi and Horning for the silylation
of hydroxyl groups on highly hindered steroids. It offers fast conversion
to TMS-ethers at a moderate temperature with a single reagent.
1. Combine 0.1-5.0 mg of steroid, 0.1-1.0 ml TMSI (0.1 ml pyridine should be
added for solubilization of cortol and cortolones) in a 1.0 or 3.0 ml
Reacti-Vial Small Reaction Vial.
2. Cap vial and heat at 100°C for 2 hours.
3. Analyze by gas chromatography.
PROTOCOL 3
1. Combine 400 µl TMSI and 800 µl pyridine (other solvents may be used) in a
3.0 ml Reacti-Vial Small Reaction Vial.
2. Add 10-15 mg sample.
3. Cap vial and shake until sample is dissolved. Heat to 60-70°C if needed.
4. Analyze by gas chromatography.
NOTE:
TMSI may be used straight with carbohydrates or as a 50% solution
with pyridine for wet sugars.
Ordering Information
Product # Description
Pkg. Size
TS-88623
TMSI
(
N
-Trimethylsilylimidazole)
10 x 1 ml ampules
TS-88625
TMSI
25 g Hypo-VialSample
Storage Vial
TS-88626
TMSI
100 g Hypo-VialSample
Storage Vial
