Cincinnati, OH, United States
Cincinnati, OH, United States

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Lanzarotta A.,Forensic Chemistry Center | Lakes K.,Miami University Ohio | Marcott C.A.,Light Light Solutions | Witkowski M.R.,Forensic Chemistry Center | Sommer A.J.,Miami University Ohio
Analytical Chemistry | Year: 2011

Advantages and limitations of analyzing authentic and counterfeit pharmaceutical tablets with both macro (nonimaging) attenuated total internal reflection Fourier transform infrared (ATR-FT-IR) spectroscopy and micro ATR-FT-IR spectroscopic imaging have been evaluated. The results of this study demonstrated that micro ATR imaging was more effective for extracting formulation information (sourcing), whereas a macro ATR approach was better suited for counterfeit detection (screening). More importantly, this study demonstrated that a thorough analysis of the counterfeit core can be achieved by combining the results of both techniques. © 2011 American Chemical Society.


Easter R.,University of Cincinnati | Easter R.,Forensic Chemistry Center | Barry C.,Forensic Chemistry Center | Caruso J.,University of Cincinnati | Limbach P.,University of Cincinnati
Analytical Methods | Year: 2013

A combined hydrophilic interaction chromatography (HILIC) electrospray ionization mass spectrometry (ESI-MS) approach for the separation and identification of phosphorothioate oligonucleotides is described. Phosphorothioate 21-mer and 23-mer were separated by HILIC and detected using selected ion monitoring (SIM) ESI-MS. Phosphorothioates could be detected from 50 nM solutions suggesting effectiveness comparable to ion pairing reversed phase chromatography approaches. © 2013 The Royal Society of Chemistry.


Lanzarotta A.,Forensic Chemistry Center
Sensors (Switzerland) | Year: 2016

A search of the current scientific literature yields a limited number of studies that describe the use of Fourier transform infrared (FT-IR) spectroscopic imaging for the analysis of forensic casework, which is likely due to the fact that these instruments are fairly new commodities to the field of analytical chemistry and are therefore not yet commonplace in forensic laboratories. This report describes recent forensic case studies that have used the technique for determining the composition of a wide variety of multi-component sample types, including animal tissue sections for toxic inclusions, drugs/dietary supplements, an antibiotic with an active pharmaceutical ingredient (API) present as several different salt forms, an adulterated bulk API, unknown trace powders for illicit drugs and an ophthalmic solution suspected of being adulterated with bleach. © 2016 by the authors; licensee MDPI, Basel, Switzerland.


PubMed | Forensic Chemistry Center
Type: Journal Article | Journal: Sensors (Basel, Switzerland) | Year: 2016

A search of the current scientific literature yields a limited number of studies that describe the use of Fourier transform infrared (FT-IR) spectroscopic imaging for the analysis of forensic casework, which is likely due to the fact that these instruments are fairly new commodities to the field of analytical chemistry and are therefore not yet commonplace in forensic laboratories. This report describes recent forensic case studies that have used the technique for determining the composition of a wide variety of multi-component sample types, including animal tissue sections for toxic inclusions, drugs/dietary supplements, an antibiotic with an active pharmaceutical ingredient (API) present as several different salt forms, an adulterated bulk API, unknown trace powders for illicit drugs and an ophthalmic solution suspected of being adulterated with bleach.


Analytes that co-elute and yield nearly identical electron ionization (EI) mass spectra, as well as analytes that yield non-specific EI fragmentation patterns, have been identified using fully integrated gas chromatography with direct deposit Fourier transform infrared detection and mass spectrometric detection (GC/FT-IR/MS). While the IR detector proved to be more selective for identifying analytes such as synthetic cannabinoids and weight loss drugs, it was limited by a relatively high detection limit of 8.4 parts per million (ppm) for non-targeted identification of sibutramine based on a single injection but was reduced to 840 parts per billion (ppb) for targeted identification of sibutramine by redepositing ten injections along the same track. The MS detector was less selective for identifying these analytes but yielded non-targeted and targeted detection limits of approximately 84 ppb and 8.4ppb, respectively, which corresponded to a 100-fold advantage compared to the IR detector. Overall, the results of this study demonstrate that the advantages of each detector compensate for the limitations of the other, which allows a wider range of analytes and concentrations to be examined using a fully integrated GC/FT-IR/MS instrument compared to what can be examined using GC/IR or GC/MS independently. Not only does this approach reduce consumption of laboratory resources and time, it provides IR and MS information on the same sample, which is important for forensic analyses that require data from two or more orthogonal techniques to make an identification.

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