Benzodiazepines are among the most prescribed compounds and are commonly present in many toxicological screens. They are also of concern forensically in cases of drug facilitated sexual assault. Currently these compounds are predominantly analyzed using immunoassay techniques; however more specific screening methods are needed. This paper demonstrates the applicability of surface enhanced Raman spectroscopy as a method for the analysis and detection of benzodiazepines. The procedure involves mixing urine extracts with gold nanoparticles and appropriate aggregating agents for trace detection of these compounds and their metabolites. In this paper we will discuss the optimization of various parameters of this technique as well as its application to screening urine samples. Eleven different benzodiazepines and metabolites were examined, including 1,2-triazolo-benzodiazepines and 1,4-benzodiazpines. Experiments were performed using four different chloride salts, MgCl2, CaCl2, KCl, and NaCl, as aggregating agents for the colloidal gold nanoparticles. Overall it was found that each aggregating agent produced different levels of signal enhancement for each drug. MgCl2 provided the lowest limit of detection at 2.5 ng mL(-1), and linearity over a wide range of concentrations for a variety of drugs chosen. It was also determined that the optimum MgCl2 concentration was 1.67 M. This method has shown the applicability of SERS for the detection of trace quantities of benzodiazepines in aqueous solutions as well as the optimization of the technique over a wide range of compounds. This technique can be utilized in the detection of trace benzodiazepines in toxicological samples following extraction of the analyte.

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At smaller institutions, resources may present a barrier to providing quality undergraduate research experiences. Course-based undergraduate research experiences (CUREs) provide collaborative environments that foster engagement with the scientific process, while promoting iterative research through the process of discovery (Auchincloss et al., 2014). We implemented an intervention-based CURE project focused on reducing exposure to potentially harmful chemicals contained in personal care products. Exposure to compounds found in personal care products, such as phthalates, is common (Silva et al., 2004) and an emerging public health concern.The research-in-classroom component of this CURE consists of analysis of urine samples from nail polish wearers to determine changes in phthalate concentrations. For this project, outside participants are recruited by independent research assistants. Participants then take a survey on their personal care product use and demographics. They are then instructed on the procedure for providing urine samples: on day one of the study, participants provide a first morning void, and remove any nail polish they are wearing; they collect first morning void samples again on days three, five, and seven. Samples are stored until analysis.In a semester-long project in Organic Chemistry II laboratory, CURE student participants then conduct analysis of the urinary samples. First, students learn and practice principles of chemical extraction and detection and underlying chemical properties such as polarity, partitioning, and chromatography. They then are presented with the intervention study and are tasked with designing their own extraction method and hypothesizing whether changes, if any, would occur in urinary phthalates following the intervention. They follow-up with performing chemical extractions and high-performance liquid chromatography (HPLC) analysis of the extracted samples to detect urinary phthalates. Finally, they analyze the course results and present their ideas for future iterations of the research project during an in-class poster session.This CURE was implemented in Spring of 2019 in two sections of Organic Chemistry II lab. Students were assessed for content competency with content-focused examinations at the beginning, middle, and end of the course. They also took pre-course and post-course PITS surveys (Hanauer et al., 2016). The first 4 weeks exposed students to methods of extraction and detection through previously-designed cookbook-style experiments. In one class period, students were introduced to the intervention study then developed and presented their own hypotheses and methods. The following five weeks were dedicated to extraction and detection of specific phthalate metabolites. Afterwards, two weeks were allotted for designing and presenting a poster detailing their results, conclusions, and proposed future iteration of the intervention study.Twenty-nine participants were initially recruited from Organic Chemistry II lab, 26 of whom completed both the pre-and post-co...

Course-based undergraduate research experiences (CUREs) provide students with ample opportunity to engage in the scientific process and are increasingly replacing more traditional cookbook-style laboratory exercises in the undergraduate biology curriculum. The COVID-19 pandemic has highlighted the difficulty of implementing these projects during times of crisis.

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