Over the years, colorimetric reagents and immunology have been widely used in screening tests for illicit drugs; however, the test kits are not always convenient for field use and often require the user to mix and develop a specific set of reagents. In our project, we have been working on alternative platforms based on paper microfluidic devices (uPADs) for field testing. These devices utilize wax channels printed on paper to direct the analyte towards a specific set of chemical reagents. Using the procedure, we have developed a six-channel chip that adapts known colorimetric reagents targeting cocaine, opiates, amphetamines and ketamine for multiplex detection. For more sensitive and specific determinations than the colorimetric reagents, we have also developed a paper device that utilizes the interaction between gold nanoparticles and drug specific aptamers. The µPADs using colorimetric reagent are designed as a six-channel multiplexed system. Sequences of different reagents applied to each channel to produce a series of reactions and the color changes appear at the end of each channel. The entire process takes less than five minutes. The adjusted reagents produce specific color changes for seized drugs on the paper microfluidic devices. Procedures have been developed for the detection of cocaine, ketamine, codeine, ephedrine, morphine, amphetamine, methamphetamine, and MDMA. These devices have been tested for sensitivity, specificity and stability against a variety of potential interferences and test conditions. Gold nanoparticles (AuNPs)/ aptamers µPADs were developed to detect cocaine. The presence of cocaine cause the binding with aptamers, and the gold nanoparitcles produced a salt-indicated aggregations and gave a color change of AuNPs from red to black. The absence of cocaine allowed the aptamers freely to bind gold nanoparticles, and no color change occured. The device had a preliminary validation of sensitvity and specificity against a variety of potential interferences. The use of paper microfluidic devices permits the development of rapid, inexpensive and easily operated tests for drug samples in the field. They present a safe and convenient presumptive tool that can be used in the field.

Research in drug development meets many challenges including lengthy, complex and costly procedures to identify novel pharmacotherapies. In our lab, we developed a method for fast screening of small molecules that interact with monoamine transports – dopamine and serotonin (DAT, SERT). These membrane proteins play important roles in brain neurotransmission responsible for cognition, motion and pleasure. Dysfunction in dopaminergic and serotonergic systems result in neurological disorders such as depression, Attention Deficit Hyperactivity Disorder (ADHD), schizophrenia and addiction. DAT and SERT are responsible for uptake of dopamine (DA) or serotonin (5HT) into the synapse and they limit neurotransmitter signaling. Drugs that mimic or antagonize actions of endogenous neurotransmitters (DA and 5HT) increase the concentrations of DA and/or 5HT either by blocking the transporter (blockers) or by competing uptake with neurotransmitter (substrate). The uptake of substrates is associated to an inward current that depolarizes the cell membrane. Voltage-gated calcium channels (CaV) can respond to small changes in membrane potential. In our method, we combined permanent cell line expressing the human dopamine transporter (hDAT) or the human serotonin transporter (hSERT) (FlpIn TREx expression system) with transient transfection of CaV. This system works as a tightly electrically coupled system. Cells challenged with substrate of the transports produce detectable Ca2+ signal while monoamine transporter blockers can inhibit these Ca2+ signals. The novelty of this method relies on the ability to discriminate between substrate and blockers of monoamine transporters. Preliminary experiments measuring our optimized cell system in a Flex Station 3 plate reader suggest that the co-expression of a voltage-gated Ca2+ channel, a monoamine transporter and a genetically encoded Ca2+ sensor constitute a rapid screening biosensor to identify active drugs at monoamine transporters. Our novel methodology can rapidly assess drug-effect profile on monoamine transporters and benefit development of new psychotherapeutics for treatment of mental illnesses. It can also be used to characterize mechanism of action of emerging drug of abuse, as well as to discover small molecules with novel drug-effect profile useful in basic neuroscience research.

No description available.

Drug prohibition has dramatically affected countries worldwide. It fuels violence and corruption in Latin America, and Central and Southeast Asia, and is a major contributing factor behind the United States having the highest rate of incarceration in the world. Yet there is scant evidence that prohibition reduces drug use. Despite this lack of evidence, prohibition is the preferred policy stance of governments worldwide. One of the primary justifications of prohibition is that drug use causes individuals’ harm. While there is evidence of individual harms associated with drug use there is also a literature suggesting it is possible to use drugs functionally – defined here as use with minimal impairment to mental and physical health, and social roles and expectations. However, drug use is a politically charged topic and as such little research on functional drug use has come to prominence. The existence of persons who use drugs functionally would allow us to consider alternative approaches to drug control that address the harms that stem from both prohibition and individual use.In this dissertation I conducted three independent but related studies to explore the existence and drivers of functional drug use. In Chapter 1 I systematically reviewed peer-reviewed literature from Ovid MEDLINE, PsycINFO, Scopus, and Web of Knowledge databases regarding functional drug use and find robust evidence that all illegal drugs can be used functionally. Drawing on the narratives of participants across the studies the typical person who uses drugs functionally is marked by three characteristics. First, they actively avoid addiction and take steps to maintain overall good physical and mental health. Second, they are socially integrated with lives that do not revolve solely around procuring and consuming drugs; hallmarks of this included holding a job, attending school, and maintaining connections to non-drug using family and friends. Third, persons who use drugs functionally take pains to avoid negative stereotypes attached to persons who use drugs – paying for their drugs with excess income, avoiding other illegal activities and attending to important socially sanctioned activities. In Chapter 2 I used data from the Inner-City Mental Health Study Predicting HIV/AIDS, Club and Other Drug Transitions (IMPACT) study, a cross-sectional dataset of former and current persons who use drugs in New York City selected via random street intercept between 2005 and 2008, to apply the findings of our review to find participants reflective of the phenomenon of functional drug use. Using exploratory latent class analysis on questions regarding drug use behaviors I report different patterns of drug use within the IMPACT sample and regress measures of social functioning on these classes as distal outcomes to assess the functionality of each class. My solution is a 6-class model consisting of the following use patterns: former non-persons who inject drugs (PWID); former PWID; marijuana use; cocaine, crack and marijuana use; low frequency polydrug use; high frequency polydrug use. Among the classes containing persons who use drugs currently, there was a clear pattern of relative functionality based on the probability of drug related interference and having an illegal main source of income. From most functional to least functional these were: marijuana use (2% interfering use; 5% illegal main source of income), cocaine, crack and marijuana use (48%; 31%), low frequency polydrug use (58%; 38%), and high frequency polydrug use (80%; 57%); compared to 37% of the overall sample reporting interfering use and 24% reporting having an illegal main source of income. Comparing the classes to former non-PWID, marijuana use had a lower odds of drug use interference (OR = 0.07, p-value < 0.01) whereas all other classes had significantly increased odds of drug use interference with increasing odds from former PWID (OR = 1.80, p-value = 0.04), cocaine, crack and marijuana use (OR = 4.46, p-value < 0.01), low frequency polydrug use (OR = 6.48, p-value < 0.01), and high frequency polydrug use (OR = 18.66, p-value < 0.01). Regarding main source of income there was no significant difference between the marijuana use class with the former non-PWID (OR = 0.88, p-value = 0.81). The other classes however, followed a similar step-wise pattern as for drug use interference: former PWID (OR = 2.68, p-value = 0.04), cocaine, crack and marijuana use (OR = 7.21, p-value < 0.01), low frequency polydrug use (OR = 10.08, p-value < 0.01), and high frequency polydrug use (OR = 21.30, p-value < 0.01). In Chapter 3 I built on the results from Chapter 2 to test whether childhood physical abuse, sexual abuse, and neglect (CAN) was associated with membership in less compared with more functional drug use classes using multinomial logistic regression. This analysis builds on literature summarized in Chapter 1 suggesting non-functional drug use is associated with feelings of negative affect and a large body of work documenting associations between CAN and psychiatric and behavioral disorders generally, and drug use specifically. I report that childhood neglect is not associated with different patterns of drug use behaviors but is positively associated with having an illegal main source of income (OR = 1.40, 95%CI 1.02, 1.92). Participants experiencing physical abuse were 1.65 (95% CI 1.06-2.59) times more likely to engage in high frequency polydrug use compared to marijuana use but had no association with drug use interference after adjustment for drug use class. There were positive associations between all measures of sexual abuse with drug use interference and having an illegal main source of income. Adjustment for drug use class accounted for the association with drug use interference but not having an illegal main source of income. This exploration of functional drug use found a strong evidence base of qualitative work supporting its existence; however, there are few extant quantitative investigations. Applying the results of our review to an epidemiologic sample I found a hierarchy of functionality related to different patterns of drug use. Moving this body of work forward requires the development of new scales to measure functional drug use to more fully characterize the phenomenon. Replication across samples will generate much needed estimates of the prevalence of functional and non-functional drug use, key data for drug policy debates. These scales should take into account the three key dimensions outlined by participants across the studies reviewed and be applicable across various kinds of drugs and meaningful cross-culturally. I report evidence supporting an association between CAN with different patterns of drug use and reduced social functioning. Future analyses should measure other sources of childhood trauma if they are interested in the direct effect of CAN on drug use, as well as modifiers of the CAN-drug use relationship to fully characterize the phenomenon. However, it should also be noted that the model this analysis is based on, like most extant theories of use, is rooted in the moral panic over drugs that has engulfed the United States for the last 100 years. These models treat drug use as unequivocally harmful, hence an irrational activity and therefore, implicitly, the result of some trauma. Functional drug use subverts this paradigm and considers multiple reasons for and patterns of use. While there are likely negative inducements towards less functional patterns of drug use we would do well to update our models by considering pleasure and incorporating both positive and negative inducements. New models should then be tested systematically across samples.

No / The impregnation of items of clothing with drugs of abuse that are then smuggled through airports and ports of entry is a growing problem for law enforcement. This work describes the application of portable Raman spectroscopic techniques for the analysis of a range of natural and artificial fibre items of clothing impregnated with drugs of abuse. Textile pieces were soaked with the solutions of the drugs then left overnight to dry prior to spectroscopic examination. The feasibility of detection of the characteristic Raman spectral bands in the presence of background matrix signals is demonstrated, even for dyed clothing. Definitive evidence for contamination of the items of clothing concerned can be acquired within 20-25 s, without any form of sample pre-treatment or extraction being necessary. The feasibility of automatic spectral recognition of such illicit materials by Raman spectroscopy has been investigated by searching a database stored on the spectrometer computer and the use of principal component analysis. Copyright (c) 2014 John Wiley & Sons, Ltd.

Thesis (Ph.D.)--University of Melbourne, Dept. of Criminology, 2007. / Typescript. Includes bibliographical references (leaves 276-305).

Drug trafficking and smuggling is an ongoing challenge for law enforcement agencies. Cocaine smuggling is a high-value pursuit for smugglers and has been attempted using a variety of concealment methods including the use of bottled liquids, canned milk, wax and suspensions in cans of beer. In particular, traffickers have used clothing impregnated with cocaine for smuggling. Handling, transportation or re-packaging of drugs of abuse and explosives will inevitably leave residual material on the clothing and other possessions of the involved persons. The nails and skin of the person may also be contaminated through the handling of these substances. This research study describes the development of Raman spectroscopic techniques for the detection of drugs of abuse and explosives on biomaterials of forensic relevance including undyed natural and synthetic fibres and dyed textile specimens, nail and skin. Confocal Raman microscopy has been developed and evaluated for the detection and identification of particulates of several drugs of abuse and explosives on different substrates. The results show that excellent spectroscopic discrimination can be achieved between single particles and substrate materials, giving a ubiquitous non-destructive approach to the analysis of pico-gram quantities of the drugs and explosives in-situ. Isolating the particle in this way corresponds with an analytical sensitivity comparable with the most sensitive analytical techniques currently available e.g. the highly sensitive, yet destructive ionization desorption mass spectrometry. With the confocal Raman approach, this work demonstrates that definitive molecular-specific information can be achieved within seconds without significant interference from the substrate. The potential for the application of this technique as a rapid preliminary, forensic screening procedure is obvious and attractive to non-specialist operators as it does not involve prior chemical pretreatment ii or detachment of the analyte from the substrate. As a result, evidential materials can be analysed without compromising their integrity for future investigation. Also, the applications of benchtop and portable Raman spectroscopy for the in-situ detection of drugs of abuse in clothing impregnated with the drugs have been demonstrated. Raman spectra were obtained from a set of undyed natural and synthetic fibres and dyed textiles impregnated with these drugs. The spectra were collected using three Raman spectrometers; one benchtop dispersive spectrometer coupled to a fibre-optic probe and two portable spectrometers. High quality spectra of the drugs could be acquired in-situ within seconds and without any sample preparation or alteration of the evidential material. A field-portable Raman spectrometer is a reliable instrument that can be used by emergency response teams to rapidly identify unknown samples. This method lends itself well to further development for the in-situ examination by law enforcement officers of items associated with users, handlers and suppliers of drugs of abuse in the forensics arena. In the last section of this study, a portable prototype Raman spectrometer ( DeltaNu Advantage 1064) equipped with 1064 nm laser excitation has been evaluated for the analysis of drugs of abuse and explosives. The feasibility of the instrument for the analysis of the samples both as neat materials and whilst contained in plastic and glass containers has been investigated. The advantages, disadvantages and the analytical potential in the forensics arena of this instrument have been discussed.

In this experiment, more than one hundred volatile organic compounds were analyzed with the gas chromatograph. Six capillary columns ZB wax plus, ZB 35, TR1MS, TR5, TG5MS and TG1301MS with different polarities have been used for separation of compounds and illicit drugs. The Abraham solvation model has five solute descriptors. The solute descriptors are E, S, A, B, L (or V). Based on the six stationary phases, six equations were constructed as a training set for each of the six columns. The six equations served to calculate the solute descriptors for a set of illicit drugs. Drugs studied are nicotine (S= 0.870, A= 0.000, B= 1.073), oxycodone(S= 2.564. A= 0.286, B= 1.706), methamphetamine (S= 0.297, A= 1.570, B= 1.009), heroin (S=2.224, A= 0.000, B= 2.136) and ketamine (S= 1.005, A= 0.000, B= 1.126). The solute property of Abraham solvation model is represented as a logarithm of retention time, thus the logarithm of experimental and calculated retention times is compared.

Though a host of analgesics have been developed to alleviate pain, especially acute pain, significant side effects and a lack of long-term efficacy have encouraged research attempts to pursue novel targets that may be associated with fewer side effects or a more sustained efficacy. Among these new targets are members of the nicotinic family of acetylcholine receptors (nAChRs). The non-selective nAChR agonists nicotine and epibatidine have been shown to function as potent antinociceptive drugs in many acute and chronic preclinical pain models, while nicotine has produced analgesic effects in humans. However, these non-selective nAChRs agonists also produce various side effects, including gastrointestinal and cardiovascular complications that limit clinical utility. To reduce these side effects, recent research has focused on evaluating the potential role of specific nAChR subtypes in the modulation of nociception. Traditionally, assays of pain-stimulated behaviors, or behaviors that increase in rate, frequency or intensity after presentation of a noxious stimulus, have been used to evaluate nAChR agonists and other classes of candidate analgesics pre-clinically. However, clinically relevant pain states are often associated with the depression of behavior; for example in humans, pain is often accompanied by impaired function in daily activities and depression of mood. To address these depressant manifestations of pain, novel preclinical assays have been developed to assess the expression and pharmacological modulation of pain-depressed behaviors, or behaviors that decrease in rate, frequency or intensity after presentation of a noxious stimulus. Additionally, the effects of nAChR agonists in preclinical assays of pain-depressed behavior are unknown. In assays of pain-stimulated behavior, agonism of α4β2* receptors appears to play a prominent role in antinociception produced by drugs that target nAChRs. Recent research suggests that α7 nAChR subtype might be an alternative target. Accordingly, the primary goal of this dissertation was to compare antinociceptive effects of the nAChR agonist nicotine and more selective nicotinic agonists in assays of pain-stimulated and pain-depressed behavior. Results from this body of work show that both nicotine and the more selective α4β2* agonist 5-I-A-85380 produced antinociception in both types of assays, whereas an α7 agonist did not. Taken together, these results suggest that α4β2* nAChR agonists may be especially effective to treat signs of pain-related behavioral depression; however nonselective behavioral effects of these compounds may contribute to apparent antinociception. Studies of nAChR agonist effects on pain-depressed behavior were conducted using an assay of intracranial self-stimulation (ICSS) as a baseline behavior that is depressed by noxious pain stimuli, and pain-related depression of ICSS can be selectively alleviated by clinically effective analgesics. As a prelude to studies of nAChR agonist effects on pain-related depression of ICSS, a preliminary study was conducted to assess effects of nicotine and 5-I-A-85380 on ICSS in the absence of a noxious stimulus. These studies indicated that selective α4β2* agonists may have higher abuse potential than nicotine. Additionally, cognitive function is one domain of behavior that may be impaired by pain, and nAChR agonists are used to treat cognitive impairment produced by other non-pain pathologies. Accordingly, a final goal of this project was to develop an assay of pain-related cognitive impairment in rats that could be used to evaluate effects of nAChR agonists. Although results of this study did provide evidence for pain-related impairment of cognition, the effects of the pain stimuli were sufficiently variable and transient to make this procedure impracticable for use in studies with nAChR agonists.

Approximately 200 million men and 100 million women smoke worldwide. In the United States, an estimated 25.9 million men (23.9 percent) and 20.7 million women (18.1 percent) are smokers. The commencement of smoking at a young age is thought to increase addiction liability, decrease the probability of successful cessation, and correlate with a higher number of cigarettes smoked per day. Studies from the World Health Organization indicate that between 80,000 and 100,000 children start smoking every day worldwide. These statistics suggest that adolescence is a critical phase for developing nicotine dependence. The work in this dissertation contributes to the further understanding of this unique developmental period. Our research shows that various aspects of nicotine dependence are both age- and sex-dependent. We observed age- and sex-related differences in both nicotine reward and withdrawal models that imply a heightened vulnerability for adolescents. In addition, we have investigated possible behavioral and molecular mechanisms which may underlie the elevated vulnerability to dependence. The data illustrate that while behavioral mechanisms only play a minor role in the differences seen in reward and withdrawal, molecular mechanisms appear to have a greater contribution. Specifically, increased nicotinic receptor function is likely to be a substantial contributor to age-related disparities. In addition, nicotine is one of the first and most commonly abused drugs in adolescence and is known to be a strong predictor of subsequent alcohol and other drug abuse. Our research investigated the effects of adolescent nicotine exposure on both nicotine and cocaine dependence in adulthood. We found that exposure to nicotine during the early phase of adolescence affects both nicotine reward and withdrawal in adulthood. Moreover, this exposure also bears impact on other drugs of abuse such as cocaine. In summary, our data suggest that early adolescence is the most critical period for becoming dependent to nicotine and that early experimentation with nicotine may lead to enhanced vulnerability to dependence on more illicit drugs of abuse. It is imperative that we understand why adolescents have a heightened susceptibility to nicotine dependence so that better smoking cessation therapies and prevention messages can be developed for this age group.