Volume 57, Issue 1 pp. 86-92
PAPER
CRIMINALISTICS

Rapid In Situ Repeatable Analysis of Drugs in Powder Form Using Reflectance Near-Infrared Spectroscopy and Multivariate Calibration

Dora Melucci M.S., Ph.D.

Dora Melucci M.S., Ph.D.

Department of Chemistry “Giacomo Ciamician,” University of Bologna, Via Selmi 2, I-40126 Bologna, Italy.

Search for more papers by this author
Dario Monti M.S.

Dario Monti M.S.

Department of Chemistry “Giacomo Ciamician,” University of Bologna, Via Selmi 2, I-40126 Bologna, Italy.

Search for more papers by this author
Marcello D’Elia M.S.

Marcello D’Elia M.S.

Gabinetto Regionale di Polizia Scientifica per l’Emilia Romagna, Via Volto Santo 3, I-40123 Bologna, Italy.

Search for more papers by this author
Giorgio Luciano Ph.D.

Giorgio Luciano Ph.D.

Institute of Marine Science, National Council for Research, Via de Marini 6, I-16149 Genoa, Italy.

Search for more papers by this author
First published: 31 October 2011
Citations: 17
Additional information and reprint requests:
Dora Melucci, M.S., Ph.D.
Department of Chemistry “Giacomo Ciamician”
University of Bologna
Via Selmi 2
I-40126 Bologna
Italy
E-mail: [email protected]

Abstract

Abstract: This study takes the first step toward in situ analysis of powder drugs which does not require any alteration of the samples. A fast, inexpensive analytical method based on reflectance near-infrared (NIR) spectrometry and multivariate calibration was applied. A diode-array fiber-optic portable spectrometer in the 900–1700 nm range was employed. Samples were laboratory-prepared ternary powders (diacetylmorphine, caffeine, and paracetamol). Partial least squares regression was applied. The choice of the standard samples for calibration and validation was performed through a D-optimal experimental design. The explained variance was higher than 90%, and the relative root mean square errors were <2%. The number of principal components (6) was very low when compared with the number of raw variables (356 absorbance values). Response plots showed slopes and intercepts were very close to optimal values. Correlation coefficients ranged between 0.909 and 0.989. The method here proposed proved to be competitive with Fourier transform NIR spectrometry.

The full text of this article hosted at iucr.org is unavailable due to technical difficulties.