Non-destructive forensic identification and quantification of cocaine through sealed packaging using FT-NIR spectroscopy and hyperspectral imaging.
Level 5 - mechanism / opinion, no new human data
Level 5 by design analogy (bench analytical chemistry and method validation)
PubMed 42242816 · doi:10.1016/j.aca.2026.345679
What was done
Researchers evaluated Fourier Transform Near-Infrared (FT-NIR) spectroscopy and near-infrared hyperspectral imaging (NIR-HSI) for non-destructive identification, classification, and quantification of cocaine through sealed polyethylene packaging. They tested seized cocaine samples obtained from four independent operations alongside six common cutting agents (creatine, caffeine, levamisole, lidocaine, lactose, and mannitol). Spectral and image data were analyzed using chemometric modeling, including Principal Component Analysis (PCA), Soft Independent Modeling of Class Analogy (SIMCA), and Partial Least Squares (PLS) regression.
What was found
FT-NIR combined with SIMCA achieved 100% sensitivity and 100% specificity for classifying cocaine versus adulterants through intact packaging. PLS regression predicted cocaine concentration with an R² of 0.95 and a Root Mean Square Error of Prediction (RMSEP) of 2.40%. Pixel-based SIMCA models applied to NIR-HSI successfully differentiated cocaine and adulterants while rejecting packaging and background materials without prior masking.
Why it matters
This method allows forensic screening and quantification of suspected illicit drugs without opening sealed evidence. It reduces chemical exposure risks for operators, maintains strict chain-of-custody integrity, and avoids destructive sampling.
Limits
The abstract does not state the total number of tested samples or the specific purity concentrations evaluated. The technique was tested only through polyethylene packaging and against six specific adulterants, leaving performance through other container types unaddressed.
Cited by
- supports Creatine is used as a cutting agent or adulterant in illicit cocaine.