Forensic Analyses by Morphologically-Directed Raman Spectroscopy

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00:00:00 Welcome
00:02:59 Forensic Analyses by Morphologically Directed Raman Spectroscopy
00:03:20 Overview
00:03:53 Introduction
00:03:54 Morphology in Forensic Science
00:04:46 Raman Spectroscopy in Forensic Science
00:05:35 Morphology + Raman Spectroscopy in Forensic Science
00:06:18 What is the MDRS?
00:07:25 Chemical correlation
00:09:02 Basic principles of MDRS
00:09:57 Forensic Application #1MDRS of Hoax Powders
00:10:15 The Hoax Powder Problem
00:10:48 Example
00:11:30 Materials and Methods – Artificial Sweeteners: Part A
00:11:50 Analytical Conditions
00:12:28 Methods
00:12:50 Results - Overall particle size distribution of blends
00:13:15 Results - PSD of MDRS Identified Bulking Agent
00:13:34 Results - PSD of MDRS Identified Sweetener
00:14:21 Results: Percentage Volume Distributions
00:14:50 Materials and Methods – Artificial Sweeteners: Part B
00:15:21 Name Brand vs. GenericNutritive Dextrose
00:15:32 Name Brand vs. GenericSucralose
00:15:59 Materials and Methods-White Powders
00:16:39 Results: Overall Distribution of Blend
00:17:06 Results: Flour & Baking Soda Distributions
00:17:24 Advantages of MDRS
00:17:38 Results: Chalk & Table Sugar Distributions
00:18:01 Volume Contributions vs Particle Size Contributions
00:18:43 ConclusionsHoax Powders
00:19:12 Forensic Application #2
00:19:18 The Illicit & Counterfeit Drug Problem
00:20:31 Illicit Drug Mixture
00:20:57 PSD of 2 Components in the Illicit Drug Mixture
00:21:40 Illicit Drug Mixture- Morphology
00:22:15 Illicit Drug Mixture – Particle Size Distributions & Morphologies
00:22:44 Bath Salts
00:23:30 MDRS of Bath Salts
00:23:46 Bath Salts – “Arctic Rush”
00:24:18 Bath Salts – “Arctic Rush”L-Dopa & Caffeine
00:24:56 Bath Salts – “Fast Forward”
00:25:35 Over-the-counter drugs
00:26:47 Contaminated Drugs
00:28:21 Counterfeit Drug Problem
00:28:59 Counterfeit Drug Problem
00:29:40 Counterfeit Viagra
00:30:05 Counterfeit Viagra
00:30:29 Counterfeit Viagra
00:30:58 ConclusionsIllicit & Counterfeit Drugs
00:31:35 Forensic Application #3
00:31:40 Why Soil?
00:32:30 Soil (for Forensic Purposes)
00:33:04 Soil Complexity
00:33:23 Why MDRS for Soil Minerals?
00:34:31 Materials and Methods – Soil Minerals
00:35:19 Quartz Site B and C – Particle Morphologies
00:35:45 Quartz PSD –Sites B vs C
00:36:26 MDRS of Soil Minerals% Particle Count
00:37:02 Chemometrics: Principal Component Analysis
00:38:46 Chemometrics: Principal Component Analysis
00:38:54 PCA of Soil Mineral Data
00:39:12 ConclusionsSoil Minerals
00:39:35 Forensic Application #4
00:39:39 Why GSR?
00:40:51 Nitrocellulose
00:41:13 Volume Distributions at Various Distances
00:42:03 ConclusionsGSR
00:42:34 Overall Conclusions
00:43:07 Acknowledgements
00:43:28 Thank You!
00:48:10 Contact Information

Morphologically-Directed Raman Spectroscopy (MDRS) can be applied to a variety of forensic evidence types such as illicit drugs, counterfeit pharmaceuticals, hoax powders, soils and gunshot residues. It is a novel and reliable tool that enables criminalists to obtain more information from forensic samples than is currently employed for investigations and adjudications. 

MDRS combines automated particle imaging and Raman spectroscopy in one instrument. Particle imaging is performed to determine particle size and shape distributions of components in a blended sample. Particle size is an important physical property of particulate samples because it has a direct influence on a variety of material properties such as reactivity or dissolution rate, suspension stability, efficacy of delivery, texture, feel, appearance, flowability, handling, viscosity, packing density and porosity. Although measurement of particle size distributions is routinely carried out across a wide range of industries and is often a critical parameter in the manufacture and analysis of many products and substances, it is not widely used in the forensic sciences. 

Raman spectroscopy is a useful technique in forensic science for determining molecular chemistry because it is rapid, reliable, does not require contact with the sample, and is non-destructive. Combining these two analytical techniques allows the individual components present within a blend or mixture to be independently characterized and compared. This presentation will demonstrate how such a tool can be used to gain a better understanding of mixtures across many areas of forensic science, as it is applicable to a range of Raman-active samples.