Classification of drugs of abuse using mass spectral data for the identification of novel psychoactive substances
- WCU Author/Contributor (non-WCU co-authors, if there are any, appear on document)
- Garion Lucas Schneider (Creator)
- Institution
- Western Carolina University (WCU )
- Web Site: http://library.wcu.edu/
- Advisor
- Nuwan Perera
Abstract: Novel psychoactive substances (NPSs) have been increasingly reported in recent years and possess significant risks to public health worldwide. These substances, sometimes known as “legal highs”, are newly designed drugs that mimic the effects of commonly abused drugs and are comprised of several drug classes which include opioids, cannabinoids, stimulants, and benzodiazepines. Many NPSs share similar chemical structures with commonly abused drugs and produce similar psychoactive responses by binding to receptors in the body. These NPSs are designed to circumvent the regulations that limit the use of recreational drugs and to create more potent drugs such as fentanyl derivatives. In a typical forensic laboratory analysis, an analyst uses a panel of known drug standards or reference materials to identify and quantify drugs present in a sample (or evidence) using chromatographic methods such as gas chromatography mass spectrometry (GCMS) or liquid chromatography mass spectrometry (LC-MS). If a compound present in the sample is not included in the test panel, mass spectral libraries can be used to find the identity of that compound by comparing the mass spectrum of the unknown with the mass spectra of known compounds present in the library. In the case of new NPSs that have not been reported, no reference materials or reference spectra are available. In this scenario, forensic labs have to rely on gathered intelligence data, prior knowledge of these NPSs, and some additional analysis methods, such as nuclear magnetic resonance spectroscopy (NMR) or high-resolution mass spectral data (HRMS), to determine the presence of NPSs. However, structural elucidation of novel compounds is time consuming and costly, thus there is a growing interest to develop methods that can proactively determine the presence of NPSs using chemometric methods. The focus of the current research work is to develop proactive solutions to identify newly designed NPSs when the reference spectra are not present in the spectral libraries used in forensic laboratories. A classification system is developed using existing data of known substances that can be used to determine the presence of NPSs. Herein, we demonstrated a model developed using mass spectral data and chemometric methods, such as principal component analysis (PCA) and partial least square discriminant analysis (PLS-DA), that can accurately discriminate novel fentanyl derivatives from non-fentanyl related drugs. Furthermore, we have developed a sub-model using aforementioned methods to discriminate fentanyl derivatives based on structural modifications. Validation results show that these methods are robust with high accuracy (>95%), true positive rates (>95%), and true negative rates (>95%).
Classification of drugs of abuse using mass spectral data for the identification of novel psychoactive substances
PDF (Portable Document Format)
9517 KB
Created on 11/1/2022
Views: 183
Additional Information
- Publication
- Dissertation
- Language: English
- Date: 2022
- Keywords
- Chemometrics, NPS, PLS-DA
- Subjects
- Medication abuse
- Substance abuse
- Psychotropic drugs
- Mass spectrometry
- Statistics