GUARDS

GUARDS

DEA’s Newly Developed GUARDS Method

THE PROBLEM: Under current jurisdictional requirements, reporting of laboratory analysis findings varies throughout municipal, county, state, and federal laboratories. This disparity sometimes results in some laboratories not reporting lower-scheduled or non-controlled substances such as fentanyl or xylazine, when found in mixtures containing a higher scheduled drug, like heroin.

THE SOLUTION: The GUARDS method was developed and validated to address these and other US-wide reporting discrepancies by providing laboratories with a standardized GC-MS screening method that allows for consistent analysis and reporting of both commonly encountered drugs as well as emergent compounds.

With DEA (and other) laboratories using the GUARDS method, data could be assessed and compared nationwide allowing the early reporting of regionally detected NPS and the monitoring of trends.

DEA Seal - Color Logo

GUARDS Vision

Develop a standardized method to separate as many compounds as possible (including isomers) to share with the forensic seized-drug community and assist in standardized identification and reporting of compounds in seized drug samples.
Decorative icons regarding the GUARDS app

Why GUARDS?

The GUARDS method offers great selectivity for the vast majority of seized drugs routinely encountered by laboratories.

Mission First:

Our mission is to turn evidence into information. A streamlined and standardized collection of information means we can collect more information with fewer methods.
 

Collaboration:

Expand collaborative partnerships and lead the forensic community by providing a standardized analysis method for seized drugs and help standardize reporting. See Figure 1

Information Sharing:

Provide and get more information into the environment to contribute to the mission and assist the community.

Benefits:

Advanced analytical information – eliminates the need for multiple chromatographic methods by separating Fluoro- & Chloro-fentanyl positional isomers and derivatization of methamphetamine enantiomers. See Figure 2

Figure 1

Consistent results standardized method
Click to enlarge
Figure_4_Chromatogram

Figure 2

Separation of fentanyl positional isomers
Click to enlarge
Chromatogram 2

Development of the Guards Method

Involved over 90 iterations and three stationary phases while monitoring system suitability using multiple sets of forensically relevant, close-eluting compounds, including fentanyl analogues and positional isomers. 

The GUARDS method offers great selectivity for the vast majority of seized drugs routinely encountered by laboratories. Table 1 lists retention time (RT) values for the 15 most frequently identified compounds in the DEA lab system (OCT ‘23 – JUL ‘24) using the GUARDS method.

Primary DrugRT (min.)

Amphetamine

2.090

Methamphetamine

2.389

3,4-MDMA

4.566

N,N-Dimethylpentylone

5.958

Ketamine

6.176

Cocaine

7.971

Δ9 THC

9.036

Hydrocodone

9.772

Oxycodone

10.379

para-Fluorofentanyl

10.743

Heroin

10.993

Fentanyl

11.205

Alprazolam

13.176

Bromazolam

13.862

Protonitazene

14.617

Table 1. 15 compounds most frequently identified throughout DEA laboratories during the first three quarters of FY 2024

RT PRECISION:  Within-day: < 0.19% RSD
Intermediate (over 5 weeks): < 1.2% RSD (DMSO2)
Reproducibility (across labs): < 5% RSD 

Compound

Avg. RT (min.)

% RSD

Avg. RRT

% RSD

Dimethyl Sulfone

1.43

4.14

0.21

2.87

Cocaine

7.94

1.34

1.14

0.13

Fentanyl (0.5%)

11.14

1.59

1.61

0.31

Trazodone

14.92

1.01

1.88

0.38

Table 2: Summary of GUARDS chromatographic results collected during verification assessments for four representative compounds across 29 instruments and 10 laboratories.