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Journal of Analytical Toxicology, Vol. 35, September 2011
Simultaneous Detection of Ten Psychedelic
Phenethylamines in Urine by Gas Chromatography–
Mass Spectrometry
Sarah Kerrigan1,2,*, Stephanie Banuelos1,†, Laura Perrella1, and Brittany Hardy1,‡
1Forensic
Science Program, College of Criminal Justice, Sam Houston State University, Box 2525, 1003 Bowers Blvd.,
Huntsville, Texas 77341 and 2Sam Houston State University Regional Crime Laboratory, The Woodlands, Texas 77381
Introduction
Abstract
Psychedelic phenethylamines are an emerging class of designer
drugs capable of producing a complex array of sought after
adrenergic and hallucinogenic effects. Toxicological detection
poses a number of challenges to laboratories. The purpose of this
study was to develop a procedure for the detection of psychedelic
amphetamines using techniques that are widely accepted in
forensic toxicology laboratories. In all, 10 target analytes were
selected: 2,5-dimethoxy-4-bromophenethylamine (2C-B),
2,5-dimethoxyphenethylamine (2C-H), 2,5-dimethoxy-4iodophenethylamine (2C-I), 2,5-dimethoxy-4ethylthiophenethylamine (2C-T-2), 2,5-dimethoxy-4-(n)propylthiophenethylamine (2C-T-7), 4-methylthioamphetamine
(4-MTA), 2,5-dimethoxy-4-bromoamphetamine (DOB),
2,5-dimethoxy-4-ethylamphetamine (DOET), 2,5-dimethoxy4-iodoamphetamine (DOI), and 2,5-dimethoxy-4methylamphetamine (DOM). Target drugs in urine were analyzed
by gas chromatography in selected ion monitoring mode after
mixed-mode solid-phase extraction. Limits of detection for all
analytes were 2–10 ng/mL, and limits of quantitation were 10
ng/mL or less. Precision evaluated at 50 and 500 ng/mL yielded
CVs of 0.4–7.9% and accuracy in the range 91–116%. Calibration
curves were linear to 1500 ng/mL using mescaline-d9 as the
internal standard. No carryover was evident at 5000 ng/mL (the
highest concentration tested) and no interferences were observed
from the presence of other structurally related compounds or
endogenous bases.
* Author to whom correspondence should be addressed: Sarah Kerrigan, Ph.D., Director,
Forensic Science Program, Sam Houston State University, Box 2525, 1003 Bowers Blvd.,
Huntsville, TX 77341. Email: [email protected].
† Current address: Texas Department of Public Safety Crime Laboratory, McAllen, TX 78501.
‡ Current address: Dallas County Institute of Forensic Sciences, Dallas, TX 75235.
The psychedelic phenethylamines described in this study
are a series of psychoactive derivatives that produce sought
after effects for recreational drug users. Many of these synthetic
psychotropics are not scheduled and bypass controlled substance legislation in the United States. Hallucinogenic
phenethylamines were first synthesized by Shulgin (1) and
later emerged as illicit drugs in Europe and Asia before making
an appearance in this country. Although the most widely
abused amphetamine in the United States is d-methamphetamine, there is still significant interest in new designer
amphetamines as the drug scene continues to evolve (2). These
emerging designer drugs include the dimethoxyphenylethanamine (2C, 2C-T) and dimethoxyphenylpropanamine
(DO) series of psychedelics, which includes 2,5-dimethoxy-4bromophenethylamine (2C-B), 2,5-dimethoxyphenethylamine
(2C-H), 2,5-dimethoxy-4-iodophenethylamine (2C-I), 2,5dimethoxy-4-ethylthiophenethylamine (2C-T-2), 2,5dimethoxy-4-(n)-propylthiophenethylamine (2C-T-7),
2,5-dimethoxy-4-bromoamphetamine (DOB), 2,5-dimethoxy-4ethylamphetamine (DOET), 2,5-dimethoxy-4-iodoamphetamine (DOI), and 2,5-dimethoxy-4-methylamphetamine (DOM).
4-Methylthioamphetamine (4-MTA) was also included in the
study because of its structural similarity, toxicity, and reported
use.
Methoxylated designer amphetamines are not new; paramethoxyamphetamine (PMA) and para-methoxymethamphetamine (PMMA) were introduced in the late 1990s, and
these were associated with fatal intoxications and acute toxicity.
Dimethoxy derivatives of phenyalkylamines are the subject of
this study. These contain methoxy groups at positions 2 and 5
of the aromatic system and often a lipophilic substituent in the
4 position. Drugs in the 2C series contain two carbons separating the amine from the aromatic core. The 2C-T series of
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Journal of Analytical Toxicology, Vol. 35, September 2011
Table I. Chemical and Mass Spectral Data for Target Analytes
Drug
Formula
2C-H
4-MTA
DOM
DOET
2C-B
DOB
2C-I
DOI
2C-T-2
2C-T-7
Mescaline-d9, IS
C10H15NO2
C10H15NS
C12H19NO2
C13H21NO2
C10H14BrNO2
C11H16BrNO2
C10H14INO2
C11H16INO2
C12H19NO2S
C13H21NO2S
C11H8D9NO3
Base
Peak
Molecular
Weight
Ions m/z*
(Ion Ratio)
152
44
166
180
232
44
278
44
212
226
191
181
181
209
223
261
274
307
321
241
255
220
152.1, 181.1 (19), 137.1 (53)
138.0, 122.0 (31), 44.0 (497)
166.1, 151.1 (35), 44.1 (158)
180.1, 165.1 (32), 91.1 (11)
232.0, 261.0 (11), 216.9 (24)
232.0, 216.9 (17), 77.1 (44)
278.0, 307.0 (14), 262.9 (19)
278.0, 262.9 (12), 77.1 (19)
212.1, 241.1 (29), 183.1 (39)
226.1, 255.1 (41), 183.0 (60)
191.0, 220.0 (22), 173.0 (53)
* Quantitation ions are underlined, and ion ratios for qualifier ions are shown in parentheses.
Figure 1. Structures of target analytes and internal standard (mescaline-d9).
Table II. Scheduling Status, Street Names, and Common Dosages
Drug
CSA
Schedule
Effective
Year
Street
Names
Common Dosage*
(mg)
2C-H
4-MTA
DOM
DOET
2C-B
Not scheduled†
Not scheduled†
I
I
I
N/A
N/A
1973
1993
1995
DOB
2C-I
DOI
2C-T-2
2C-T-7
I
Not scheduled†
Not scheduled†
Not scheduled†
I
1973
N/A
N/A
N/A
2004
N/A
Flatliner, Golden Eagle
STP (Serenity, Tranquility, Peace)
Hecate
2’s, Bees, Bromo, Nexus,
Spectrum, Toonies, Venus
Bob, Dr. Bob
i
N/A
T2
Beautiful, Blue Mystic, T7,
Tripstasy, Tweety-Bird Mescaline
Unknown
N/A
3–10
2–6
12–24
Unknown
N/A
14–20
14–20
4–8
1–3
14–22
1.5–3
12–25
10–30
18–30
6–10
16–30
6–8
8–15
* Dosage and duration of action are reported from testimonial and nonscientific literature (1,3).
† May be regulated under the Federal Analogue Act (4).
460
Duration
(h)
drug are sulfur containing, and many are
derivatives of 4-thioamphetamine. Some
drugs within this class differ by just one
substituent or atom, and share very similar chemical and physical properties.
Molecular data and structures for the
psychedelic amphetamines described in
this study are depicted in Table I and
Figure 1, respectively.
A number of these drugs are Schedule
I drugs in the Federal Controlled Substances Act (CSA) because of the high potential for abuse and absence of either
medical use or accepted safety. Although
most of these substances are considered
“drugs or chemicals of concern” by the
Drug Enforcement Administration (DEA),
several remain unscheduled to date (2CH, 2C-I, 2C-T-2, DOI, and 4-MTA). Instead, they may be regulated by the Federal Analogue Act, which states that any
drug substantially similar to a scheduled
drug may be treated as though it were
scheduled, if intended for human consumption. Scheduling status, street
names, dosages, and duration of action
for the drugs included in this study are
summarized in Table II (3,4).
There is very limited published scientific literature concerning the pharmacology or toxicology of these psychedelic
amphetamines. A common route of administration is oral ingestion; however,
insufflation, smoking, and rectal use are
not uncommon, and intravenous and intramuscular administrations have been
reported (2). Some of the psychedelic
phenethylamines show affinity to 5HT2
receptors, acting as potent and selective
5HT2C receptor agonists and 5HT2A receptor antagonists (5). Although these
drugs are still the subject of ongoing
study, it appears clear that their somewhat unique properties are mediated
largely by serotonergic and adrenergic receptors. Many are capable of producing
central nervous system effects, euphoria
and enhanced visual, auditory, olfactory,
or physical sensations similar to LSD;
however, reported effects are highly dosedependent (1,6). Overdose and death are
of concern, and fatal intoxications have
been associated with the use of 2C-T-7,
4-MTA, and DOB (7–12).
From 2004 through 2010, the DEA
published numerous reports of drug
seizures throughout the United States
(13–45). Reports are not geographically
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Table III. Summary of Published Procedures for Analysis
Drugs of Interest
Matrix
Extraction
Internal Standard
Instrumentation
Derivatization
Reference(s)
4-MTA
NB*
none
none
GC–MS, CE–DAD, ATR/FTIR, 1HNMR
None
47
4-MTA
Blood
Urine
LLE
Fenfluramine
Diethylpropion
HPLC–DAD, GC–NPD
None
7
4-MTA
Blood
Urine
Vitreous
Tissue
LLE
Phentermine
LC–MS–MS
None
9
4-MTA
Blood
LLE
Diphenylamine
GC–MS, HPLC–DAD
None
8
2C-B
Urine
LLE
None
GC–MS
Isobutyric anhydride
48
2C-T-7
Blood
Urine
Tissue
LLE
TMA
GC–MS
None
10
2C-B
Urine
LLE
2C-T-7
GC–MS
N-Butyric anhydride
49
2C-T-2
Urine
LLE
None
GC–MS
None
50
2C-B, 4-MTA
Urine
SPE
None
HPLC–UV
None
51
2C-B, 2C-T-7
Blood
Urine
SPE
Mescaline-d9
5-Fluorotryptamine
GC–MS, LC–MS
PFPA
52
DOB
Blood
Urine
LLE
Brompheniramine
GC–MS
Acetic anhydride
12
2C-B, 2C-I, DOB,
DOI, DOM
Urine
SPE
None
CE–MS
None
53
4-MTA
Urine
LLE
None
GC–MS
Acetic anhydride
54
2C-B, 2C-I,
2C-T-2, 2C-T-7
Blood
SPE
AM-d5, MA-d5, MDA-d5,MDMA-d5,
MDEA-d5, mescaline-d9
GC–MS
HFBA
5
2C-T-2, 2C-T-7
Urine
LLE
None
GC–MS
Acetic anhydride
55,56
DOB
Urine
LLE
None
GC–MS
Acetic anhydride
57
2C-B, 2C-I, 2C-T-2,
2C-T-7, 4-MTA,
Mescaline
Urine
SPE
Medazepam
GC–MS
Acetic anhydride
58
2C-I
Urine
LLE
None
GC–MS, CE–MS
Acetic anhydride
59
2C-B, 2C-I,
2C-T-2, 2C-T-7
Urine
LLE
None
CE–NF, CE–LIF, GC–MS
Fluorescence derivatization
60
DOB
NB
None
None
CE–DAD, MSn, FTIR, GC–MS
None
61
DOI
Urine
LLE
None
GC–MS
Acetic anhydride
62
DOM, DOET
Urine
SPE
None
CE–MS
None
63
2C-B
Urine
LLE
None
GC–MS
Acetic anhydride
64
DOM
Urine
LLE
None
GC–MS
Acetic anhydride
65
2C-B
Tissue
Blood
SPE
MBDB
GC–MS
Acetic anhydride
66
2C-B, 2C-H, 2C-I,
Blood
2C-T-2, 2C-T-7, 4-MTA,
DOB, DOET, DOM
SPE
AM-d5, MDMA-d5,
MDEA-d5, cocaine-d3
LC–MS–MS
None
67
* Abbreviations: NB, nonbiological matrix; LLE, liquid extraction; SPE, solid-phase extraction; TMA, trimethoxyamphetamine; amphetamine-d5, AM-d5; methamphetamine-d5, MA-d5;
3,4-methylenedioxyamphetamine-d5, MDA-d5; 3,4-methylenedioxymethamphetamine-d5, MDMA-d5; 3,4-methylenedioxy-N-ethylamphetamine-d5, MDEA-d5; 2-methylamino-1-(3,4methylenedioxyphenyl)-butane, MBDB; GC, gas chromatography; MS, mass spectrometry; CE, capillary electrophoresis; DAD, diode-array detection; ATR/FTIR, attenuated total
reflectance/Fourier transform infrared spectroscopy; 1H-NMR, proton nuclear magnetic resonance; HPLC, high-performance liquid chromatography; NPD, nitrogen-phosphorus detection;
LC, liquid chromatography; UV, ultraviolet spectrometry; NF, native fluorescence detection; LIF, light emitting diode (LED)-induced fluorescence detection; MSn, tandem mass spectrometry;
PFPA, pentafluoropropionic anhydride; and HFBA, heptafluorobutyric anhydride.
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isolated: they include Tennessee, Georgia, Arkansas, Kentucky,
Florida, Pennsylvania, California, New Mexico, Wisconsin, Oklahoma, Oregon, Iowa, Michigan, New York, South Dakota,
and Texas. Most of these designer amphetamines are recovered
in powder, tablet, or blotter form, although some have been encountered as liquids and capsules. LSD-like “blotters” are particularly common for 2C-I, DOB, and DOI. There are numerous
reports of these psychedelic phenethylamines being sold as
Ecstasy mimic tablets and “acid” blotter mimics (13–46).
Users report a variety of sought after effects including
psychedelic ideation, a sense of well being, emotional awakening, profound insight, closed and open-eyed visuals, increased appreciation of music, introspection and emphathogenesis. Other effects include increased blood pressure, blurred
vision, dehydration, nausea, vomiting, headache, dilated pupils,
muscle tension, and tachycardia.
These recreational drugs are not routinely assayed in
forensic toxicology laboratories and there is limited data concerning their prevalence in toxicological casework. Existing
published studies are summarized in Table III (47–67). Some
describe the analysis of non-biological samples (i.e., seized
drugs), others use techniques that are not in widespread use in
toxicology laboratories, and most target some, but not all, of
the drugs described in this study. Gas chromatography–mass
spectrometry (GC–MS) is still the most widely used technique
for confirmatory toxicology analysis. Most of the published
methods to date are limited in their ability to simultaneously
identify more than a few of the psychedelic phenethylamines of
interest. Ishida et al. (58) developed a method for the detection
of 30 abused drugs in human urine using GC–MS, including
2C-B, 2C-I, 2C-T-2, 2C-T-7, and 4-MTA. However, there is no literature to date that describes a comprehensive screening procedure for some of the most common 2C, 2C-T, and DO series
designer drugs using GC–MS.
Some published methods utilizing GC–MS derivatize these
amphetamine-like drugs using acetic anhydride, n-butyric anhydride, isobutyric anhydride, heptafluorobutyric anhydride,
and pentafluoropropionic anhydride (Table III). Derivatization
has many advantages from the standpoint of improved detectability, volatility, specificity, and chromatographic separation. However, in this study drugs were not derivatized. Nonderivatized drugs can be advantageous if a laboratory is making
an identification using a commercial or widely used mass spectral library, particularly if the laboratory conducts full scan
screening by GC–MS. The purpose of this study was to establish a simple procedure for the separation and identification of
the 10 target drugs in urine, using techniques and instrumentation already widely used in human performance and
medical examiner’s toxicology laboratories.
Experimental
Materials and methods
2C-B, 2C-H, 2C-I, 2C-T-2, 2C-T-7, (±)-4-MTA, (±)-DOB, (±)DOET, and (±)-DOM were obtained from Lipomed (Cambridge,
MA). DOI, phenethylamine, putrescine, tryptamine, and tyra-
462
mine were obtained from Sigma-Aldrich (St. Louis, MO).
Mescaline-d9, (±)-amphetamine, (±)-methamphetamine, (±)methylenedioxyamphetamine (MDA), (±)-methylenedioxymethamphetamine (MDMA), (±)-methylenedioxyethylamphetamine (MDEA), (±)-methylbenzodioxolylbutanamine
(MBDB), (–)-ephedrine, (+)-pseudoephedrine, phentermine,
and (±)-phenylpropanolamine were obtained from Cerilliant
(Round Rock, TX). PolyCrom Clin II (3 cc) solid-phase extraction (SPE) columns (catalog #691-0353) containing 35 mg
polymeric sorbent were obtained from SPEware (Baldwin Park,
CA). Deionized water was purified through a Millipore Milli Q
water system (Billerica, MA). Acetic acid, hexane, ethyl acetate, methanol, methylene chloride, and isopropyl alcohol
were obtained from Mallinckrodt-Baker (Hazelwood, MO). Ammonium hydroxide was obtained from Fisher Scientific (Pittsburgh, PA). Sodium phosphate monobasic monohydrate (ACS
grade) and sodium phosphate dibasic heptahydrate (ACS grade)
were purchased from Sigma-Aldrich (St. Louis, MO) and VWR
(West Chester, PA), respectively, and used to prepare a 0.1 M
phosphate buffer solution (pH 6). All inorganic reagents and
solvents were ACS or HPLC grade or higher. A solution of
methylene chloride and isopropyl alcohol was prepared at a
ratio of 95:5 (v/v). The elution solvent was prepared with 95:5
v/v methylene chloride/isopropyl alcohol and ammonium hydroxide at a ratio of 98:2 (v/v).
Mescaline-d9 internal standard solution was prepared in
methanol at a concentration of 0.01 mg/mL. Working standards of 2C-B, 2C-H, 2C-I, 2C-T-2, 2C-T-7, 4-MTA, DOB, DOET,
DOI, and DOM were prepared in methanol at concentrations
appropriate for the fortification of calibrators and controls. An
amphetamine interference solution consisted of amphetamine, methamphetamine, MDA, MDMA, MDEA, MBDB,
ephedrine, pseudoephedrine, phentermine, and phenylpropanolamine in methanol. An endogenous interference solution consisted of phenethylamine, putrescine, tryptamine,
and tyramine in methanol. Pooled drug-free urine containing
1% sodium fluoride (w/v) was used to prepare all calibrators
and controls.
Instrumentation
GC–MS analysis was performed using an Agilent HP 5975
MSD/6890 GC (Santa Clara, CA) with a DB-5MS (30 m × 0.25
mm × 0.25 μm) capillary column purchased from VWR (West
Chester, PA). The injector and interface were both set at 280°C.
Injections (2 μL) were made in split mode with a 5:1 split
ratio. Ethyl acetate was used as the wash solvent, with a total
of six pre-and post injection syringe washes between samples.
The oven temperature was held at 130°C for 0.50 min, ramped
to 170°C at a rate of 15°C/min with a hold time of 1 min,
ramped to 180°C at a rate of 5°C/min with a hold time of 9 min,
ramped to 200°C at a rate of 15°C/min and then ramped to
290°C at a rate of 30°C/min with a final hold time of 1 min. The
total run time was 20.0 min. Helium was used as the carrier gas
at a flow rate of 1.3 mL/min. The MS was operated in the electron impact (EI) ionization mode. The ion source and
quadrupole were set at 230°C and 150°C, respectively. Data was
acquired using selected ion monitoring (SIM) using quantitation and qualifier ions shown in Table I.
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Extraction
A methanolic working standard was used to prepare all calibrators and controls. In the absence of deuterated analogues
for each of the target drugs, a number of alternatives were
evaluated. These included deuterated analogues of MDMA,
MBDB, and mescaline. Mescaline-d9 was structurally similar
and yielded the most promising results during method development. After addition of internal standard (IS) solution to 2
mL urine (250 ng/mL, IS), 2 mL phosphate buffer (0.1M, pH
6.0) was added. Buffered urine samples were added to PolyCrom Clin II columns (catalog #691-0353) and successively
rinsed using 1 mL deionized water and 1 mL 1 M acetic acid.
Columns were dried under full vacuum for 5 min and then
rinsed with 1 mL hexane, 1 mL ethyl acetate, and 1 mL
methanol. Drugs of interest were eluted using 1 mL of 2%
ammonium hydroxide in 95:5 (v/v) methylene chloride/isopropyl alcohol in silanized conical borosilicate glass tubes. Extracts were evaporated to dryness under nitrogen at 50°C, reconstituted in 20 μL of ethyl acetate, and transferred to
autosampler vials for analysis.
Assay performance
Although quantitative analyses are not routinely performed
on urine samples, the new procedure was evaluated qualitatively and quantitatively in order to determine overall assay performance. The analytical recovery was estimated by comparison of the relative peak areas of target analytes. Urine
containing internal standard was extracted with (250 ng/mL)
and without target drugs. The extract containing internal standard alone was fortified with target drugs (250 ng/mL) immediately after the extraction, prior to the evaporation step. Samples were reconstituted and analyzed by GC–MS. The analytical
recovery (extraction efficiency) was calculated from the relative
peak area (drug/IS) of extracted and non-extracted samples.
The limit of detection (LOD) was defined as the lowest concentration of analyte that met the following criteria: signal-tonoise (S/N) ratio of at least 3:1 for the total ion chromatogram;
ion ratios for both qualifiers within acceptable ranges (±20%);
and a retention time within 2% of the expected value. The
limit of quantitation (LOQ) was defined as the lowest concen-
tration of analyte that met the following criteria: S/N ratio of
at least 10:1 for the total ion chromatogram; ion ratios for
both qualifiers within acceptable ranges (±20%); the retention
time within 2% of the expected value; and a calculated concentration within 20% of the expected value. The LOD and
LOQ were assessed using urine fortified with psychedelic amphetamine working standard. For the purpose of the LOQ, the
urine calibrators were prepared using independently prepared
stock solutions at to give final concentrations of 2, 10, and 20
ng/mL.
Accuracy and precision were assessed by replicate analysis
(n = 4) of drug-free urine fortified with target drugs at 50 and
500 ng/mL. Linear regression analysis was used to determine
the limit of linearity of the assay, and carryover was evaluated
using drug-free matrix injected immediately after extracts containing high concentrations of target drugs.
Interferences were evaluated using a number of structurally
related substances, endogenous bases, and common drugs.
From a quantitative standpoint, an interference was defined as
a substance that caused the calculated concentrations of a
target drug to deviate from the expected value by more than
±20%. The potential interference of other abused amphetamine-like drugs was investigated. Negative and positive
(250 ng/mL) controls were assayed in the presence of 1 mg/L
of amphetamine-like drugs (amphetamine, methamphetamine,
MDA, MDMA, MDEA, MBDB, ephedrine, pseudoephedrine,
phentermine, phenylpropanolamine); endogenous bases
(phenethylamine, putrescine, tryptamine, tyramine); and
common basic drugs, including dextromethorphan, zolpidem,
ketamine, diphenhydramine, cocaine, amitriptyline, diazepam,
nordiazepam, oxycodone, hydrocodone, alprazolam, phencyclidine (PCP), methadone, tramadol, and codeine.
Results and Discussion
Analytical recovery, LOD, and LOQ
Analytical recoveries for each of the target drugs were 63–
94% (Table IV). The lowest recoveries were generally observed
Table IV. Summary of Analytical Specifications Including Recovery, Limit of Detection (LOD), Limit of Quantitation (LOQ),
and Correlation Coefficients (r2) for the Linear Range
Drug
Recovery
(%)
LOD
(ng/mL)
LOQ
(ng/mL)
Calculated Concentration
at the LOQ
(ng/mL)
Linear
Range
(ng/mL)
r2
2C-H
4-MTA
DOM
DOET
2C-B
DOB
2C-I
DOI
2C-T-2
2C-T-7
70
71
63
64
94
74
92
72
86
78
10
2
2
2
2
2
2
2
5
5
10
10
5
2
5
2
5
10
10
10
11.1
9.9
5.8
2.1
4.8
1.9
5.1
10.8
8.6
8.1
0–1500
0–1500
0–1500
0–1500
0–1500
0–1500
0–1500
0–1500
0–1500
0–1500
0.997
0.994
0.995
0.993
0.997
0.992
0.990
0.988
0.990
0.993
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for the DO series of drugs. During the method development
stage it was necessary to increase the polarity of the elution solvent (using isopropanol) in order to optimize recovery. An elution solvent consisting of 2% ammonium hydroxide in 95:5 v/v
Table V. Signal-to-Noise (S/N) Ratios and Calculated
Concentrations at the LOQ
Drug
m/z
S/N Ratio*
2C-H
152
181
137
TIC
79:1
110:1
35:1
10:1
4-MTA
138
122
44
TIC
103:1
13:1
20:1
31:1
DOM
166
151
44
TIC
570:1
151:1
20:1
34:1
DOET
180
165
91
TIC
430:1
103:1
18:1
119:1
2C-B
232
261
217
TIC
212:1
122:1
24:1
52:1
DOB
232
217
77
TIC
398:1
19:1
18:1
63:1
2C-I
278
307
263
TIC
100:1
84:1
16:1
32:1
DOI
278
263
77
TIC
184:1
21:1
15:1
39:1
2C-T-2
212
241
183
TIC
67:1
76:1
10:1
10:1
2C-T-7
226
255
183
TIC
49:1
46:1
10:1
17:1
* S/N ratios were evaluated for the total ion chromatogram (TIC) and for each
acquired ion.
464
methylene chloride/isopropyl alcohol was optimal for methoxylated drugs. LODs ranged from 2 to 10 ng/mL, and LOQs were
10 ng/mL or less for all analytes (Table IV). Calculated concentrations for controls run at the quantitation limits are also
shown, and Table V shows the corresponding signal-to-noise ratios for the total ion chromatogram (TIC) and acquired ions.
Low LODs are preferable for this class of drug because of the
limited pharmacological data in humans and the absence of
metabolites from commercial sources.
The most challenging drugs to separate and identify were the
following pairs of structurally related compounds: 2C-B and
DOB; 2C-I and DOI. Despite the structural similarity, chromatographic and spectroscopic resolution was achieved for all
10 target drugs. Representative urine extracts containing 10
and 100 ng/mL of each drug are depicted in Figure 2 and extracted ion chromatograms are shown in Figure 3.
Precision, accuracy, and linearity
Precision and accuracy data are summarized in Table VI.
Accuracy was 91–116% and 98–109% at 50 and 500 ng/mL, respectively. Corresponding CVs were 0.9–6.5% and 0.4–5.6%, respectively. Calibrations were linear from 0 to 1500 ng/mL for
all drugs, and correlation coefficients are given in Table IV. No
carryover was evident following injection of an extract containing 5000 ng/mL of target drugs. During method development, a comparison of silanized and non-silanized glassware
indicated the former to be preferable. This suggests that some
of the methoxylated species may have a tendency to adsorb to
the surface of glass.
Interferences
Interferences were evaluated qualitatively and quantitatively
using negative and positive controls fortified with potential
interferants. None of the amphetamine-like drugs (am-
Figure 2. Total ion chromatograms of target drugs in urine at 10 ng/mL (A)
and 100 ng/mL (B). All extracts contain 250 ng/mL of mescaline-d9 (internal
standard).
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phetamine, methamphetamine, MDA,
MDMA, MDEA, MBDB, ephedrine, pseudoephedrine, phentermine, and phenylpropanolamine) or endogenous bases
(phenethylamine, putrescine, tryptamine,
and tyramine) interfered with the assay.
With the exception of MDMA, all amphetamine-like and endogenous bases
eluted prior to data acquisition (solvent
delay 5 min). Negative controls remained
blank and quantitative controls containing target drugs at 250 ng/mL produced calculated concentrations within
82–104% of expected values for stimulants, and 81–116% for endogenous
amines. In the presence of common alkaline drugs, both 2C-I and 2C-T-7 quantitated outside of the acceptable ±20%
range (79% for both). Although this appeared marginal, negative controls were
always drug-free, indicating the absence
of interfering ions from these species. Although the quantitative discrepancy was
very small, it was reproducible. There was
no obvious source of the possible interference because none of the common
drugs coeluted with the target analytes
with the exception of 2C-I and phencyclidine at relative retention times of 1.80
and 1.79, respectively (Table VII).
Limitations
Figure 3. Extracted ion chromatograms for target analytes and internal standard in urine at 10 ng/mL (A)
and 100 ng/mL (B). Internal standard (mescaline-d9) was present at 250 ng/mL.
Pharmacological and toxicological data
for many of these drugs are still somewhat limited. However, animal and, to a
lesser extent human, studies for select
drugs within the class suggest a number
of common metabolic pathways. The DO
series of drugs may undergo hydroxylation of the 4 methyl, followed by conjugation or oxidation to the corresponding
acid, deamination (to a ketone), reduction to an alcohol, O-demethylation, or
combinations of these pathways (57,62,
65). In a somewhat similar fashion, proposed pathways for the 2C series include
O-demethylation, deamination, alcohol
formation, acid formation, reduction, and
acetylation (48,49,59,64,66). Sulfur-containing drugs in the 2C-T series likely undergo similar transformations, in addition to S-depropylation followed by
methylation of the resulting thiol
(50,55,56). Conjugation (glucuronidation
and sulfation) takes place and several
metabolic studies employ a deconjugation step prior to the identification of proposed metabolites.
465
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A significant limitation, however, is the absence of commercial standards for these metabolites. From a practical
standpoint, this limits most laboratories to the identification of
the parent drug alone. Although concentrations of 2C-T-7 in
heart blood and urine were 57 ng/mL and 1120 ng/mL following a fatality (10), concentrations in recreational drug users
are not well established. DOB concentrations in serum following a fatal overdose were particularly low (19 ng/mL) (12),
but this is perhaps not surprising considering the very low
dose (1–3 mg) of this drug (Table II). Authors of this study tentatively identified
urinary metabolites in addition to DOB,
but were unable to identify them because
of the absence of a commercial standard.
stances. In this study, we report a simple alkaline SPE to isolate drugs of interest, followed by GC–MS analysis of underivatized extracts. Although the metabolic transformation of
these drugs has been preliminarily investigated and likely involves a number of common pathways, commercial standards
are not readily available. Toxicology laboratories performing
routine human performance or postmortem investigations
must therefore rely upon detection of the parent drug. Using
the approach described here, a total of 10 designer drugs were
Conclusions
The 2C, 2C-T, and DO series of designer
drugs pose a number of challenges to
forensic toxicology laboratories. Although
these drugs are seized by law enforcement
agencies throughout the United States,
they are not readily detected in forensic
toxicology laboratories. It is not clear
whether these drugs are rarely encountered due to overall low prevalence or limitations with respect to detectability.
Commercial immunoassays have limited
cross-reactivity towards these amphetamine-like drugs. As a consequence,
laboratories that rely upon immunoassay
rather than more broad spectrum chromatographic screening techniques may
fail to detect these and other similar sub-
Figure 3 (continued). Extracted ion chromatograms for target analytes and internal standard in urine at
10 ng/mL (A) and 100 ng/mL (B). Internal standard (mescaline-d9) was present at 250 ng/mL.
Table VI. Precision and Accuracy at 50 and 500 ng/mL
50 ng/mL
500 ng/mL
Drug
Calculated
Concentration
(ng/mL)
Mean ± SD
(n = 4)
Calculated
Concentration
(ng/mL)
Mean ± 95% CI
(n = 4)
Accuracy
(%)
2C-H
4-MTA
DOM
DOET
2C-B
DOB
2C-I
DOI
2C-T-2
2C-T-7
46.2 ± 0.5
50.8 ± 4.0
50.4 ± 1.3
49.2 ± 1.3
47.4 ± 0.4
46.3 ± 1.5
47.7 ± 0.5
45.4 ± 1.3
48.0 ± 3.1
57.8 ± 0.9
46.2 ± 0.9
50.8 ± 6.4
50.4 ± 2.1
49.2 ± 2.0
47.4 ± 0.7
46.3 ± 2.3
47.7 ± 0.8
45.4 ± 2.1
48.0 ± 4.9
57.8 ± 1.5
93
102
101
98
95
93
95
91
96
116
466
%CV
(n = 4)
Calculated
Concentration
(ng/mL)
Mean ± SD
(n = 4)
Calculated
Concentration
(ng/mL)
Mean ± 95% CI
(n = 4)
Accuracy
(%)
%CV
(n = 4)
1.2
7.9
2.6
2.5
0.9
3.1
1.1
2.9
6.52
1.67
494.2 ± 20.3
488.3 ± 26.5
499.4 ± 14.5
498.7 ± 9.7
524.2 ± 2.3
502.1 ± 7.4
522.5 ± 8.4
508.6 ± 5.3
518.4 ± 15.7
545.4 ± 30.7
494.2 ± 32.3
488.3 ± 42.1
499.4 ± 23.1
498.7 ± 15.4
524.2 ± 3.7
502.1 ± 11.7
522.5 ± 13.4
508.6 ± 8.5
518.4 ± 25.0
545.4 ± 48.8
99
98
100
100
105
100
105
102
104
109
4.1
5.4
2.9
1.9
0.4
1.5
1.6
1.0
3.0
5.6
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targeted in one assay with very low detection limits, sufficient
to identify parent drug in urine samples. Using this approach,
2C, 2C-T, and DO series drugs could be incorporated somewhat
readily into a laboratory’s existing analytical procedures where
necessary.
Acknowledgments
This project was supported by Award No. 2008-DN-BX-K126
awarded by the National Institute of Justice, Office of Justice
Programs, U.S. Department of Justice. The opinions, findings,
and conclusions or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect
those of the Department of Justice.
Table VII. Relative Retention Times of Target Analytes
and Other Drugs
Drug
Relative Retention Time
MDMA
0.71
2C-H
0.72
4-MTA
0.76
MDEA
0.78
DOM
0.83
MBDB
0.86
DOET
0.94
Mescaline-d9
1.00
Tryptamine
1.13
2C-B
1.35
DOB
1.38
Ketamine
1.60
Diphenhydramine
1.66
PCP
1.79
2C-I
1.80
DOI
1.84
2C-T-2
1.95
Tramadol
2.07
2C-T-7
2.23
Methadone
2.41
Dextromethorphan
2.42
Amitriptyline
2.47
Cocaine
2.47
Codeine
2.62
Diazepam
2.66
Hydrocodone
2.67
Nordiazepam
2.72
Oxycodone
2.73
Zolpidem
2.98
Alprazolam
2.82
References
1. A. Shulgin and A. Shulgin. Phenethylamines I Have Known and
Loved (PiHKAL): A Chemical Love Story. Transform Press,
Berkeley, CA, 1991.
2. R. Haroz and M.I. Greenberg. New drugs of abuse in North
America. Clin. Lab. Med. 26: 147–164 (2006).
3. The Vaults of Erowid. Psychoactive Vaults. www.erowid.org (accessed April 2010).
4. Drug Enforcement Administration. List of Scheduling Actions.
http://www.deadiversion.usdoj.gov (accessed January 2011).
5. V. Habrdova, F.T. Peters, D.S. Theobald, and H.H. Maurer.
Screening for and validated quantification of phenethylamine-type
designer drugs and mescaline in human blood plasma by gas
chromatography/mass spectrometry. J. Mass Spectrom. 40: 785–
795 (2005).
6. National Drug Intelligence Center: U.S. Department of Justice. Information Bulletin. 2C-B (Nexus) reappears on the club drug
scene. May 2001.
7. S.P. Elliott. Fatal poisoning with a new phenethylamine: 4methylthioamphetamine (4-MTA). J. Anal. Toxicol. 24: 85–89
(2000).
8. E.A. De Letter, V.A. Coopman, J.A. Cordonnier, and M.H. Piette.
One fatal and seven non-fatal cases of 4-methylthioamphetamine
(4-MTA) intoxication: clinico-pathological findings. Int. J. Legal
Med. 114: 352–356 (2001).
9. T. Dacaestecker, E. De Letter, K. Clauwert, M. Bouche, W. Lambert, J. Van Bocxlaer, M. Piette, E. Van den Eeckhout, C. Van Peteghem, and A. De Leenheer. Fatal 4-MTA intoxication: development of a liquid chromatographic–tandem mass spectrometric
assay for multiple matrices. J. Anal. Toxicol. 25: 705–710 (2001).
10. B. Curtis, P. Kemp, L. Harty, C. Choi, and D. Christensen. Postmortem identification and quantitation of 2,5-dimethoxy-4-npropylthiophenethylamine using GC–MSD and GC–NPD. J. Anal.
Toxicol. 27: 493–498 (2003).
11. European Monitoring Centre for Drugs and Drug Addiction. Report on the risk assessment of 2C-I, 2C-T-2, and 2C-T-7 in the
framework of the joint action on new synthetic drugs, 2004.
12. M. Balíková. Non-fatal and fatal DOB (2,5-dimethoxy-4bromoamphetamine) overdose. Forensic Sci. Int. 153: 85–91
(2005).
13. U.S. Drug Enforcement Administration. 4-Bromo-2,5dimethoxyphenethylamine (2C-B, “Nexus”) tablets seized in Tennessee. Microgram Bull. 42(11): 84 (2009).
14. U.S. Drug Enforcement Administration. Blotter acid mimic (actually containing 4-bromo-2,5-dimethoxy-amphetamine (DOB) and
4-chloro-2,5-dimethoxy-amphetamine (DOC)) in Pratt County,
Kansas. Microgram Bull. 42(4): 36 (2009).
15. U.S. Drug Enforcement Administration. Blotter acid mimic (actually containing a mixture of 4-chloro-2,5-dimethoxyamphetamine
and 4-bromo-2,5-dimethoxyamphetamine) in Warner Robins,
Georgia. Microgram Bull. 42(3): 25 (2009).
16. U.S. Drug Enforcement Administration. Ecstasy mimic tablets
(actually containing 4-iodo-2,5-dimethoxyphenethylamine hydrochloride (2C-I) in Sherwood, Arkansas. Microgram Bull. 41(8):
72 (2008).
17. U.S. Drug Enforcement Administration. Solutions of 4-ethyl-2,5dimethoxyphenethylamine (2C-E) in dropper bottles in Kentucky.
Microgram Bull. 41(7): 60 (2008).
18. U.S. Drug Enforcement Administration. LSD blotter acid mimics
(actually containing 4-iodo-2,5-dimethoxyamphetamine (DOI)
and 4-chloro-2,5-dimethoxyamphetamine (DOC)) in Lantana,
Florida. Microgram Bull. 41(6): 53 (2008).
19. U.S. Drug Enforcement Administration. Poly-drug seizure of hallucinogens in Upper Darby Township, Pennsylvania. Microgram
Bull. 41(3): 27 (2008).
20. U.S. Drug Enforcement Administration. LSD blotter acid mimic
(actually containing a mixture of 4-chloro-2,5-dimethoxyamphetamine (DOC) and 4-iodo-2,5-dimethoxyamphetamine
467
Kerrigan 956.qxd:JATLynneTemplate
7/27/11
11:24 AM
Page 10
Journal of Analytical Toxicology, Vol. 35, September 2011
(DOI)) in Paducah, Kentucky. Microgram Bull. 41(3): 28 (2008).
21. U.S. Drug Enforcement Administration. LSD blotter acid mimics
containing 4-chloro-2,5-dimethoxy-amphetamine (DOC) in Concord, California. Microgram Bull. 40(12): 110 (2007).
22. U.S. Drug Enforcement Administration. Recent, unusual drug submissions in New Zealand. Microgram Bull. 40(12): 110 (2007).
23. U.S. Drug Enforcement Administration. 4-Chloro-2,5-dimethoxyamphetamine (DOC) in Santa Fe, New Mexico. Microgram Bull.
40(10): 93 (2007).
24. U.S. Drug Enforcement Administration. 4-Iodo-2,5dimethoxyamphetamine (DOI) in Madison, Wisconsin. Microgram Bull. 40(9): 89 (2007).
25. U.S. Drug Enforcement Administration. Capsules containing 2,5dimethoxy-4-ethylphenethylamine (2C-E) in Tulsa, Oklahoma.
Microgram Bull. 40(4): 38 (2007).
26. U.S. Drug Enforcement Administration. Aqueous solutions of 4chloro-2,5-dimethoxyamphetamine (DOC) in Tampa, Florida. Microgram Bull. 40(4): 42 (2007).
27. U.S. Drug Enforcement Administration. Large polydrug seizure
near Salem, Oregon. Microgram Bull. 40(2): 20–22 (2007).
28. U.S. Drug Enforcement Administration. Blotter acid mimics (containing 4-bromo-2,5-dimethoxyamphetamine (DOB)) in Concord,
California. Microgram Bull. 40(2): 24 (2007).
29. U.S. Drug Enforcement Administration. LSD blotter acid mimics
(containing 4-bromo-2,5-dimethoxy-amphetamine (DOB)) in
Ames, Iowa. Microgram Bull. 39(12): 145 (2006).
30. U.S. Drug Enforcement Administration. Blotter acid mimics (containing 4-bromo-2,5-dimethoxy-amphetamine (DOB)) in Concord, California. Microgram Bull. 39(11): 136 (2006).
31. U.S. Drug Enforcement Administration. 4-Chloro-2,5-dimethoxyamphetamine (DOC) and 4-iodo-2,5-dimethoxyamphetamine
(DOI) in Berkley, Michigan. Microgram Bull. 39(11): 137 (2006).
32. U.S. Drug Enforcement Administration. Ecstasy mimic tablets
(containing meta-chlorophenyl-piperazine (MCPP)), and capsules
containing 2,5-dimethoxy-4-iodophenethylamine (2C-I), in Iowa.
Microgram Bull. 39(9): 112 (2006).
33. U.S. Drug Enforcement Administration. LSD blotter acid mimics
(containing 2,5-dimethoxy-4-chloro-amphetamine (DOC)) in
Boca Raton, Florida. Microgram Bull. 39(6): 72 (2006).
34. U.S. Drug Enforcement Administration. LSD blotter acid mimics
(containing 4-iodo-2,5-dimethoxy-amphetamine (DOI)) in
Orlando and Winter Springs, Florida. Microgram Bull. 39(5): 55
(2006).
35. U.S. Drug Enforcement Administration. 2C-I capsules in Miami
Beach, Florida. Microgram Bull. 39(1): 3–4 (2006).
36. U.S. Drug Enforcement Administration. LSD blotter acid mimic
containing 4-chloro-2,5-dimethoxy-phenethylamine (2C-C) in
Washington County, Oregon. Microgram Bull. 38(11): 163 (2005).
37. U.S. Drug Enforcement Administration. LSD blotter acid mimic
containing 4-bromo-2,5-dimethoxy-amphetamine (DOB) seized
near Burns, Oregon. Microgram Bull. 38(10): 147–148 (2005).
38. U.S. Drug Enforcement Administration. 2,5-Dimethoxy-4ethylphenethylamine (2C-E) capsules in Bettendorf, Iowa. Microgram Bull. 38(4): 59 (2005).
39. U.S. Drug Enforcement Administration. 2C-B laboratory seized in
Tioga County, New York. Microgram Bull. 37(12): 208–209
(2004).
40. U.S. Drug Enforcement Administration. 2,5-dimethoxy-4ethylphenethylamine (2C-E) encountered in Ft. Pierce, Florida
and Royal Oak, Michigan. Microgram Bull. 37(11): 193 (2004).
41. U.S. Drug Enforcement Administration. Additional information on
the MDMA laboratory in Marion, South Dakota. Microgram Bull.
37(7): 130 (2004).
42. U.S. Drug Enforcement Administration. Dipropyltryptamine and
2C-I in Portland, Oregon. Microgram Bull. 37(6): 113–114 (2004).
43. U.S. Drug Enforcement Administration. 2C-I tablets in the Balearic
Islands (Spain). Microgram Bull. 37(3): 48–49 (2004).
44. U.S. Drug Enforcement Administration. Unusual polydrug seizure
in Ellsworth, Kansas. Microgram Bull. 37(1): 8 (2004).
45. U.S. Drug Enforcement Administration. Psilocybe mushrooms,
468
46.
47.
48.
49.
50.
51.
52.
53.
54.
55.
56.
57.
58.
59.
60.
dimethyltryptamine, MDMA and 4-bromo-2,5-dimethoxyphenethylamine (2C-B, Nexus) seized in Albany, Oregon. Microgram
Bull. 43(3): 8 (2010).
U.S. Drug Enforcement Administration. Ecstasy mimic tablets actually containing 4-bromo-2,5-dimethoxyphenethylamine (2CB, Nexus) seized in Houston, Texas. Microgram Bull. 43(7): 69
(2010).
A.J. Poortman and E. Lock. Analytical profile of 4-methylthioamphetamine (4-MTA), a new street drug. Forensic Sci. Int. 100:
221–233 (1999).
T. Kanamori, H. Inoue, Y. Iwata, Y. Ohmae, and T. Kishi. In vivo
metabolism of 4-bromo-2,5-dimethoxyphenethylamine (2C-B) in
the rat: identification of urinary metabolites. J. Anal. Toxicol. 26:
61–66 (2002).
T. Kanamori, K. Tsujikawa, Y. Ohmae, Y. Iwata, H. Inoue, Y. Inouye,
and T. Kishi. Excretory profile of 4-bromo-2,5-dimethoxyphenethylamine (2C-B) in rat. J. Health Sci. 49: 166–169 (2003).
L.-C. Lin, J.-T. Liu, S.-H. Chou, and C.-H. Lin. Identification of 2,5dimethoxy-4-ethylthiophenethylamine and its metabolites in the
urine of rats by gas chromatography–mass spectrometry. J. Chromatogr. B 798: 241–247 (2003).
M. Soares, M. Carvalho, H. Carmo, F. Remiao, F. Carvalho, and
M. Bastos. Simultaneous determination of amphetamine derivatives in human urine after SPE extraction and HPLC–UV analysis.
Biomed. Chromatogr. 18: 125–131 (2004).
S.P. Vorce and J.H. Sklerov. A general screening and confirmation
approach to the analysis of designer tryptamines and phenethylamines in blood and urine using GC–ESI-MS and HPLC–electrospray-MS. J. Anal. Toxicol. 28: 407–410 (2004).
G. Boatto, M. Nieddu, A. Carta, A. Pau, M. Palomba, B. Asproni,
and R. Cerri. Determination of amphetamine-derived designer
drugs in human urine by SPE extraction and capillary electrophoresis with mass spectrometry detection. J. Chromatogr. B
814: 93–98 (2005).
A.H. Ewald, F.T. Peters, M. Weise, and H.H. Maurer. Studies on
the metabolism and toxicological detection of the designer drug
4-methylthioamphetamine (4-MTA) in human urine using gas
chromatography–mass spectrometry. J. Chromatogr. B 824: 123–
131 (2005).
D.S. Theobald, S. Fehn, and H.H. Maurer. New designer drug, 2,5dimethoxy-4-propylthio-β-phenethylamine (2C-T-7): studies on
its metabolism and toxicological detection in rat urine using gas
chromatography/mass spectrometry. J. Mass Spectrom. 40: 105–
116 (2005).
D.S. Theobald, R.F. Staack, M. Puetz, and H.H. Maurer. New designer drug 2,5-dimethoxy-4-ethylthio-β-phenethylamine (2C-T-2):
studies on its metabolism and toxicological detection in rat urine
using gas chromatography/mass spectrometry. J. Mass Spectrom.
40: 1157–1172 (2005).
A.H. Ewald, G. Fritschi, W-R. Bork, and H.H. Maurer. Designer
drugs 2,5-dimethoxy-4-bromo-amphetamine (DOB) and 2,5dimethoxy-4-bromo-methamphetamine (MDOB): studies on their
metabolism and toxicological detection in rat urine using gas
chromatographic/mass spectrometric techniques. J. Mass Spectrom. 41: 487–498 (2006).
T. Ishida, K. Kudo, H. Inoue, A. Tsuji, T. Kojima, and N. Ikeda.
Rapid screening for and simultaneous semiquantitative analysis of
thirty abused drugs in human urine samples using gas chromatography–mass spectrometry. J. Anal. Toxicol. 30: 468–477
(2006).
D.S. Theobald, M. Putz, E. Schneider, and H.H. Maurer. New designer drug 4-iodo-2,5-dimethoxy-β-phenethylamine (2C-I):
studies on its metabolism and toxicological detection in rat urine
using gas chromatographic/mass spectrometric and capillary electrophoretic/mass spectrometric techniques. J. Mass Spectrom. 41:
872–886 (2006).
C.-C. Tsai, J.-T. Liu, Y.-R. Shu, P.-H. Chan, and C.-H. Lin. Optimization of the separation and on-line sample concentration of
phenethylamine designer drugs with capillary electrophoresis–fluorescence detection. J. Chromatogr. A 1101: 319–
Kerrigan 956.qxd:JATLynneTemplate
7/27/11
11:24 AM
Page 11
Journal of Analytical Toxicology, Vol. 35, September 2011
323 (2006).
61. J.L. da Costa, A.Y. Wang, G.A. Micke, A.O. Maldaner, R.L. Romano, H.A. Martins-Junior, O.N. Neto, and M.F. Tavares. Chemical identification of 2,5-dimethoxy-4-bromoamphetamine (DOB).
Forensic Sci. Int. 173: 130–136 (2007).
62. A.H. Ewald, G. Fritschi, and H.H. Maurer. Metabolism and toxicological detection of the designer drug 4-iodo-2,5-dimethoxyamphetamine (DOI) in rat urine using gas chromatography–mass
spectrometry. J. Chromatogr. B 857: 170–174 (2007).
63. M. Nieddu, G. Boatto, and G. Dessi. Determination of 4-alkyl 2,5
dimethoxy-amphetamine derivatives by capillary electrophoresis
with mass spectrometry detection from urine samples. J. Chromatogr. B 852: 578–581 (2007).
64. D.S. Theobald, G. Fritschi, and H.H. Maurer. Studies on the toxicological detection of the designer drug 4-bromo-2,5-dimethoxy-
β-phenethylamine (2C-B) in rat urine using gas chromatography–
mass spectrometry. J. Chromatogr. B 846: 374–377 (2007).
65. A.H. Ewald, M. Puetz, and H.H. Maurer. Designer drug 2,5dimethoxy-4-methyl-amphetamine (DOM, STP): involvement of
the cytochrome P450 isoenzymes in formation of its main
metabolite and detection of the latter in rat urine as proof of a
drug intake using gas chromatography–mass spectrometry. J. Chromatogr. B 862: 252–256 (2008).
66. M. Rohanová, T. Páleníc̆ek, and M. Balíková. Disposition of 4bromo-2,5-dimethoxyphenethylamine (2C-B) and its metabolite
4-bromo-2-hydroxy-5-methoxyphenethylamine in rats after subcutaneous administration. Toxicol. Lett. 178: 29–36 (2008).
67. A. Wohlfarth, W. Weinmann, and S. Dresen. LC–MS/MS screening
method for designer amphetamines, tryptamines, and piperazines
in serum. Anal. Bioanal. Chem. 396: 2403–2414 (2010).
469