TLCTLC--AccuTOFAccuTOF DARTDART

10ème anniversaire du Club de CCM23/10/2008

Akihiko KUSAI, JEOL (Europe) SAS

AccuTOF DART

Unless marked otherwise, DART is interfaced to a JEOL AccuTOFtm

time-of-flight mass spectrometerHigh resolution and exact mass measurements provide selectivityHigh dynamic range makes it easyto measure mixturesExact masses and accurate isotopic abundances permit identification of unknownsFast data acquisition for high throughputMass-independent abundance response (small molecules)

What is DART?

DART is a rapid and non-contact surface sampling technique for mass spectrometry at atmospheric pressure under ambient conditions. (Ambient ionization technique)DART can be used to analyze any compounds; gases, liquids, solids and materials on surfaces.DART is suitable to analyze small-moleculecompounds (with some exceptions).

Analyte mast be vaporized in the gas phase.

DART Review

Compounds in gas phase are Ionized by metastables

He, N2, …

Electron, charged molecules, and energetic atoms or gas molecule are formed by glow discharge.

Electrodes block the charged particles and electrons.

Features of DART

Analysis time is very quick: analysis completes in seconds.

TOFMS is suitable for DART due to fast data samplingDART operation is very simple.

Open-air operationNo vacuum, No solvent, No carryover

DART is not susceptible to high levels of saltsDART is applicable to any compounds in gas phase

Gases, liquids, solids and ,materials on surfacesDART spectrum is very simple like a APCI spectrum

No alkali-metal adducts or multiple charges

With a glass rod for liquid sample

With tweezers for solid sample

Sample introduction

With a weighting paper for powder sample, not solved sample, etc.

DART Applications

Forensics

Drugs (medicinal, herbal, illicit, counterfeit)

ExplosivesChemical warfare agents

Metabolites

Synthetic organics

Foods & beveragesPesticides

Toxic industrial materials

Polymer & additives

A BA ＋ B → AB

PurificationPurification

CABD

Silica-gel

A Bsample

TLC

AB?

Reaction Reaction monitoringmonitoring

LC/MS Reverse-phase

Normal-phase

Possible to confirm the mass information of products and by-products.

Impossible to know the condition for isolating the products

EasySimple

Normal-phase

How DART can be used in the synthetic organics

BAB C

DA

Direct reaction monitoring by DART

Check product Check product by DARTby DART

To the next step

1,5 hexanediol acetylation (add excess HOAc at 90 minutes)

-20

0

20

40

60

80

100

120

0 20 40 60 80 100 120 140

Time

Rel

. abu

ndan

ce (%

)

1,5-HexanediolMonoacetateDiacetate

Direct reaction monitoring

1,5-Hexanediol acetylation (add excess HOAc at 90 min.)

1,5-Hexanediol

Diacetate

Monoacetate

Published application by TLC-DART

Molrock, Gertrud and Ueda, Yoshihisa. New coupling of planar chromatography with direct analysis in real time mass spectrometry. Jounal of chromatography A, 1143, 2007, 243-251Natalle J. Smith, Marek A Domin, and Lawrence T. Scott, HRMS Directly From TLC Slides. A Powerful Tool for Rapid Analysis of Organic Mixtures, Organic Letters, 2008, Vol.10, No.16, 3493-3496.

TLC plate sampler

Maximum size of TLC plate: 10mm × 100mm

TLC sampler

Overlapped spots

MS[1];0.311..0.329;- 1.0*MS[1];0.346..0.391; / ESI+ / azo test 001

100 150 200 250 300Ž ¿—Ê“ d‰×” ä(m/ z)

0

10

20

30

40

‹ -“ x (41066)x103

198.10

199.11

197.10

m/z 245

MS[1];0.390..0.412;- 1.0*MS[1];0.329..0.374; / ESI+ / azo test 001

100 150 200 250 300Ž ¿—Ê“ d‰×” ä(m/ z)

0

1000

2000

‹ -“ x (2955)

245.13

227.16

244.12

226.15120.08

246.14228.17177.12135.10

119.07 298.20163.14

m/z 198

m/z 227 m/z 245

4-aminoazobenzene

3,3’-dimethoxybenzidine4,4’-diamino-3,3’-dimethyldiphenylmethane

Analysis of azo compounds by TLC/DART

Feature of TLC Auto-Slider

Constant speed drivingControllable of driving speed (0.5, 1.0, 2.0 and 4.0 mm/sec)

Good reproducibilityImprovement of making a chromatogramAvailable to obtain Rfvalue

ƒ }ƒ Xƒ Nƒ �[1];748.50700..748.62900; / ESI+ / clarith TLC 004

0 0.2 0.4 0.6 0.8 1.0Œo‰ßŽ žŠ Ô[min]

0

10

‹ -“ x (14352)x103

0.113

Rf = 0.113(min) / 0.5(min) = 0.23Spot size = ca. 5(mm)

ca. 5 sec

Clarithromycin (C38H69NO13)

Sliding speed : 1.0 mm/sec

MS[1];0.104..0.128;- 1.0*MS[1];0.187..0.222; / ESI+ / clarith TLC 004

200 400 600 800 1000Ž ¿—Ê“ d‰×” ä(m/ z)

0

5

10

‹ -“ x (13241)x103

748.56

149.10

749.57

590.46750.58

[M+H]+748.56

Analysis of macrolide antibiotics extracted by CHCl3

Measurement end

CHCl3/CH3OH=9/1

30mm

<JMS<JMS--T100TD>T100TD>

Conclusion

DART analysis is fast, easy and “no sample prep” (most of the time…)Simple mass spectra is obtained by DART. It is easy to make a interpretation.TLC/MS is the useful tools for high-throughput identification in the synthetic organics.