A microfluidic device for presumptive testing of controlled substances.

Area of Science:

• Forensic Chemistry
• Analytical Chemistry
• Microfluidics

Background:

• Traditional spot plate methods for controlled substance analysis are resource-intensive.
• There is a need for more efficient and sensitive analytical techniques in drug testing.

Purpose of the Study:

• To develop and validate a microfluidic device (MFD) for simultaneous color and crystal tests of controlled substances.
• To compare the MFD method's efficiency and sensitivity against traditional methods.

Main Methods:

• Development of a microfluidic device with four analytical channels (one for crystal tests, three for color tests).
• Validation using target analytes (methamphetamine, amphetamine, cocaine, oxycodone) and specific reagents (platinic chloride, Marquis, Simon, cobalt thiocyanate).
• Comparative analysis with traditional spot plate methods regarding sample/reagent use, waste generation, and operator dependency.

Main Results:

• The MFD demonstrated picogram-level limits of detection.
• Effective detection of controlled substances in complex mixtures at 5-10% (w/w) concentrations.
• Microcrystal tests within the MFD showed higher sensitivity than color tests.
• Reagent use and waste generation were reduced by 95% compared to traditional methods.
• Device performance was operator independent.

Conclusions:

• The developed microfluidic device offers a highly sensitive, efficient, and robust platform for controlled substance analysis.
• MFDs provide a significant advancement over traditional methods, reducing environmental impact and improving analytical information yield.
• The technology is suitable for routine forensic and analytical applications, offering reliable results across different operators.