MS

Internaticmd

of Mass Spectrometry

Journal

FORENSIC APPLICATIONS

J.

253

48 (1983) 253-256 Printed in The Netherlands

and Ion Physics,

Elsevier Scientific Publishing Company, Amsterdam -

OF LC/MS

YINON

Department

of

Isotope

Weizmann

Research,

Institute

of

Science,

Rehovot,

Israel

ABSTRACT A high performance liquid chromatograph (HPLC) has been interfaced with a magnetic sector mass spectrometer using a connnercial direct liquid introduction (DLI) interface allowing about 1% of the solvent/sample effluent into the ion The LC/MS system has been used for the analysis of forensic mixtures source. including explosives and drugs.

INTRODUCTION In

many

which

applications

combines

good

tive

detection.

over

GC/MS in

for

The

explosive

sives

and

is

been

characteristics system

suitable

used

with

has

such

for

thermally

successfully

(refs.l,2)

specific

an analytical

analysis,

for

sensitive

and

has

and

involatile

has

and

required

and an

sensi-

advantage com-

separation

spectrometry

detection

is

specific

an analytical

mass

the

highly

specifications

as

while

method

method

technique

proven

itself

identification

of

as

explo-

(refs.7,3).

Several

LC/MS

techniques

(refs

analysis the

LC/MS

it

mixtures

a sensitive

forensic

separation

that

HPLC has

pounds.

of

of

of

magnetic

sector

analysis

of

been an

using

drugs

Paper

have Such

exp?osives

analysis ‘In this

systems ,4-8).

described

LC/MS

using

system

negative

ion

has

various already

chemical

interface been

ionization

coupling

applied

to

(ref.9)

and

the to

(refs.lO,ll).

we describe mass

results

spectrometer

standard

mixtures

obtained and

of

from

using

explosives

interfacing

the

combined

and

drugs.

an H.PLC with

LC/MS

system

for

a the

EXPERIMENTAL The- LC/MS The

mass

system

with

an

(Menlo

The

7125

Park, Eldex

Sample

column

is

a high-speed

an

Prograrrmer, Model

shown

spectrometer

strument Eldex

is

used

in

a home

Calif.)

was

OOZO-7381/83/0000-0000/$03.00

1. built

differential

Model

Injector

Fig.

Model LP-II and

a RP-8

4-inch

A-30-S

a Waters

radius

an Eldex

Valve,

(Milford,

sector

Model

CMT-II (Cotati,

Model

Lichrosorb

in-

HPLC consists

a Rheodyne Mass.)

column,

magnetic The

system.

pump,

Low Pressure

reversed/phase 0

90”

pumping

441

of

Gradient Calif.).

UV detector.

10 Urn particle

1983 Elsevier Scientific Publishing Company

254

Fig. 1.

Photograph

showing

size, 4.6 mm x 10 cm length was methanol:water

(50:50)

the K/MS

(Brownlee

system.

Labs.,

Santa

Clara,

at a flow rate of 1 mL/min.

Calif.).

Mobile

UV detector

phase

wavelength

was 214 nm. The LC/MS Direct

interface

Liquid

interface.

The

electrically made

glass

vacuum RESULTS

Interface

probe

slides

which

(Palo Alto,

is a variable

into a heated

CaTif.) split-type

desolvation

the ion source

(which

is at 1500 Volts)

(Corning

Works,

Corning,

enters

Glass

vaporized

in the desolvation

the ion source

of the ion source

of the vacuum

chamber,

where

by means

but which

by a tube

N-Y.). chamber,

it is ionized.

of a valve which

connects

chamber,

and

the

It is possible

is located

the ion source

with

on the

AND DISCUSSION

the operation Only

from

Hewlett-Packard

housing.

A series

of standard

explosive

of the LC/MS

two examples

mixture

LC/MS

interface

ceramic

mixture

the opening

the outside

Probe

of the jet are

droplets

solvent/sample to vary

LC/MS

insulated

of Macor

The

Insertion

is a commercial

and Figs.

are given

system here.

3 and 4 show

and drug mixtures and

was analyzed

its application

Fig. 2 shows

the respective

in forensic

the HPLC-UV

mass

spectra

trace

to demonstrate analysis. of a RDX+TNT

of the two components.

255 COLUiMN METHANOL. UV

: RP-

8 WATER(50:

WAVELENGTH:

501, 2 t4

TfME Fig.

2.

HPLC-UV

Fig.

3.

K/MS

Iml/mfn

“m

[

min

trace

mass

1 of

RDX+TNT

spectrum

of

mixture.

RDX (Source

temp.

17OOC).

m/r

Fig.

4.

LC/MS

mass

spectrum

of

TNT

(Source

temp.

17OY).

256 Fig. 5 shows spective

the HPLC-UV

mass

spectra

of a drug mixture

of the two components,

and Figs.

6 and 7 show the re-

acetaminophen

and barbital.

100

COLUMN: RF-8 METHANOL: WATER UV

trace

(50:

WAVELENGTH

214

501,

LC/

I ml/ tin 109

-I

nm

MS

METHANOL:

Leo

WATER(50:

ACETAMINOPHEN M+

% 2

501

60

a

160 Fig. 6.

0

2

I

TIME

Fig. 5.

3

LC/MS mass

of acetaminophen.

4

[m,n]

HPLC-UV

trace

120

As the source

was mostly

of EI and CI spectra.

open,

A better

sure seems to be necessary. on distance

of jet from source

These

parameters

have

the obtained

continuous

Also,

spectrum

mass

variation

spectra

and on source to be kept

mass

of barbital

spectra

are a combination

possibility

depend

strongly

and desolvation

constant

+&i----

180

160 m/z

140

LC/MS mass

Fig. 7.

tures.

spectrum

in order

of source

pres-

on jet length,

chamber to obtain

temperareproduc-

ibility. REFERENCES 1

J. Yinon and S. Zitrin, The Analysis of Explosives, Pergamon Press, Oxford, 1981, 322 pp. 2 1-S. Krull and M.J. Camp, American Laboratory, May 1980, 63-76. 3 J. Yinon, Mass Spectrometry Reviews, in press. 4 P. Arpino, M.A. Baldwin and F.W. McLafferty, Biom. Mass Spectrom., 1 (1974)eO-82 5 W.H. McFadden, H.L. Schwartz and S. Evans, 3. Chromatogr., 122 (1976) 389-396. 6 J.D. Henion, J. Chromatogr. Sci., 19 (1981) 57-64. 7 K.H. Schafer and K. Levsen, J. Ghromatogr., 206 {1981) 245-252. 8 T. Takeuchi, D. Ishii, A. Saito and T. Ohki, J. of HRC & CC, 5 (1982) 91-92. 9 C.E. Parker, R.D. Voyksner, Y. Tondeur, J.D. Henion, J.R. Hass and J. Yinon, J. Forensic Sci., in press. 10 J.D. Henion and G.A. Maylin, Biom. Mass Spectrom., 7 (1980) 115-121, 11 P-J. Arpino

and P.

Krien,

J. Chromatogr.

Sci.,

18 11980)

104.