Screening tablets for DOB using surface-enhanced Raman spectroscopy.

Area of Science:

• Analytical Chemistry
• Forensic Science
• Spectroscopy

Background:

• 2,5-Dimethoxy-4-bromoamphetamine (DOB) is an "ecstasy" variant with a dangerous delay between consumption and effect, increasing overdose risk.
• Conventional screening methods struggle to detect DOB in tablets due to its low active dose (0.2-3 mg) and interference from excipients in normal Raman spectra.

Purpose of the Study:

• To report the first application of on-tablet surface-enhanced Raman spectroscopy (SERS) for enhancing signals of low-concentration drugs in tablets.
• To demonstrate the efficacy of SERS in detecting and identifying DOB in seized ecstasy tablets.

Main Methods:

• Developed an on-tablet SERS technique using silver colloid and NaCl solution on model and seized DOB/lactose tablets.
• Utilized 785-nm excitation Raman spectroscopy with short signal accumulation times (approx. 20 seconds).
• Analyzed tablets containing DOB concentrations ranging from 1 mg down to 15 microg.

Main Results:

• On-tablet SERS dramatically enhanced the DOB signal, completely dominating the spectra over the lactose excipient.
• DOB was clearly identified even in model tablets containing as little as 15 microg of the drug.
• The method provided unique spectral fingerprints for DOB identification.

Conclusions:

• On-tablet SERS is a simple and rapid method for distinguishing low-dose DOB tablets from those without the active ingredient.
• The technique allows for quick (<1 min) and effective identification of DOB in seized drug samples without extensive sample preparation.