Development of a Graphene-Oxide-Deposited Carbon Electrode for the Rapid and Low-Level Detection of Fentanyl and Derivatives.

The opioid overdose crisis in North America worsened during the COVID-19 pandemic, with multiple jurisdictions reporting more deaths per day due to the fentanyl-contaminated drug supply than COVID-19. The rapid quantitative detection of fentanyl in the illicit opioid drug supply or in bodily fluids at biologically relevant concentrations (i.e., <80 nM) remains a significant challenge. Electroanalytical techniques are inexpensive and can be used to rapidly detect fentanyl, but detection limits need to be improved. Herein, we detail the development of an electrochemical-based fentanyl analytical detection strategy that used a glassy carbon electrode modified with electrochemically reduced graphene oxide (ERGO) via electrophoretic deposition. The resulting surface was further electrochemically reduced in the presence of fentanyl to enhance the sensitivity. Multiple ERGO thicknesses were prepared in order to prove the versatility and ability to fine-tune the layer to the desired response. Fentanyl was detected at <10 ppb (<30 nM) with a limit of detection of 2 ppb and a calibration curve that covered 4 orders of concentration (from 1 ppb to 10 ppm). This method was sensitive to fentanyl analogues such as carfentanil. Interference from the presence of 100-fold excess of other opioids (heroin, cocaine) or substances typically found in illicit drug samples (e.g. caffeine and sucrose) was not significant.

On the Structure of Sulfur/1,3-Diisopropenylbenzene Co-Polymer Cathodes for Li-S Batteries: Insights from Density-Functional Theory Calculations.

Sulfur co-polymers have recently drawn considerable attention as alternative cathode materials for lithium-sulfur batteries, thanks to their flexible atomic structure and the ability to provide high reversible capacity. Here, we report on the atomic structure of sulfur/1,3-diisopropenylbenzene co-polymers (poly(S-co-DIB)) based on the insights obtained from density-functional theory calculations. The focus is set on studying the local structural properties, namely the favorable sulfur chain length (Sn with n = 1 ⋯ 8 ) connecting two DIBs. In order to investigate the effects of the organic groups and sulfur chains separately, we perform series of atomic structure optimizations. We start from simple organic groups connected via sulfur chains and gradually change the structure of the organic groups until we reach a structure in which two DIB molecules are attached via sulfur chains. Additionally, to increase the structural sampling, we perform temperature-assisted minimum-energy structure search on slightly simpler model systems. We find that in DIB-Sn -DIB co-polymers, shorter sulfur chains with n ∼ 4 are preferred, where the stabilization is mostly brought about by the sulfur chains rather than the organic groups. The presented results, corresponding to the fully charged state of the cathode in the thermodynamic limit, have direct applications in the field of lithium-sulfur batteries with sulfur-polymer cathodes.

A Neuropharmacological Model to Explain Buprenorphine Induction Challenges.

Buprenorphine induction for treating opioid use disorder is being implemented in emergency care. During this era of high-potency synthetic opioid use, novel and divergent algorithms for buprenorphine induction are emerging to optimize induction experience, facilitating continued treatment. Specifically, in patients with chronic fentanyl or other drug exposures, some clinicians are using alternative buprenorphine induction strategies, such as quickly maximizing buprenorphine agonist effects (eg, macrodosing) or, conversely, giving smaller initial doses and slowing the rate of buprenorphine dosing to avoid antagonist/withdrawal effects (eg, microdosing). However, there is a lack of foundational theory and empirical data to guide clinicians in evaluating such novel induction strategies. We present data from clinical studies of buprenorphine induction and propose a neuropharmacologic working model, which posits that acute clinical success of buprenorphine induction (achieving a positive agonist-to-withdrawal balance) is a nonlinear outcome of the opioid balance at the time of initial buprenorphine dose and mu-opioid-receptor affinity, lipophilicity, and mu-opioid-receptor intrinsic efficacy (the "ALE value") of the prior opioid. We discuss the rationale for administering smaller or larger doses of buprenorphine to optimize the patient induction experience during common clinical situations.

Towards an International Consensus on the Prevention, Treatment, and Management of High-Risk Substance Use and Overdose among Youth.

Background and Objectives: Now more than ever, there is an obvious need to reduce the overall burden of disease and risk of premature mortality that are associated with mental health and substance use disorders among young people. However, the current state of research and evidence-based clinical care for high-risk substance use among youth is fragmented and scarce. The objective of the study is to establish consensus for the prevention, treatment, and management of high-risk substance use and overdose among youth (10 to 24 years old). Materials and Methods: A modified Delphi technique was used based on the combination of scientific evidence and clinical experience of a group of 31 experts representing 10 countries. A semi-structured questionnaire with five domains (clinical risks, target populations, intervention goals, intervention strategies, and settings/expertise) was shared with the panelists. Based on their responses, statements were developed, which were subsequently revised and finalized through three iterations of feedback. Results: Among the five major domains, 60 statements reached consensus. Importantly, experts agreed that screening in primary care and other clinical settings is recommended for all youth, and that the objectives of treating youth with high-risk substance use are to reduce harm and mortality while promoting resilience and healthy development. For all substance use disorders, evidence-based interventions should be available and should be used according to the needs and preferences of the patient. Involuntary admission was the only topic that did not reach consensus, mainly due to its ethical implications and resulting lack of comparable evidence. Conclusions: High-risk substance use and overdoses among youth have become a major challenge. The system's response has been insufficient and needs substantial change. Internationally devised consensus statements provide a first step in system improvement and reform.

Optimized effective potentials to increase the accuracy of approximate proton transfer energy calculations in the excited state.

Many fundamental chemical reactions are triggered by electronic excitations. Here, we propose and benchmark a novel approximate first-principles molecular dynamics simulation idea for increasing the computational efficiency of density functional theory-based calculations of the excited states. We focus on obtaining proton transfer energy at the S1 excited state through actual density functional theory calculations at the T1 state with additional optimized effective potentials. The potentials are optimized as such to reproduce the excited-state energy surface obtained using time-dependent density functional theory, but can be generalized to other more accurate quantum chemical methods. We believe that the presented method is not only suitable for studies on excited-state proton transfer and ion mobility in general systems but can also be extended to investigate more involved processes, such as photo-induced isomerization.

A Case Report: Rapid Micro-Induction of Buprenorphine/Naloxone to Administer Buprenorphine Extended-Release in an Adolescent With Severe Opioid Use Disorder.

BACKGROUND AND OBJECTIVES: Buprenorphine extended-release (BUP-XR) is a monthly injectable form of opioid agonist therapy. Before its administration, a minimum 7-day induction period with a transmucosal buprenorphine-containing product is recommended. METHODS: Case report (n = 1). RESULTS: A 16-year-old female with active, severe opioid use disorder (OUD) and stimulant use disorder, hepatitis C virus, co-occurring mental health disorders, and complex social stressors had five recent overdoses requiring naloxone. She had previously been treated with methadone and several trials of sublingual buprenorphine/naloxone, but would quickly discontinue the treatment. Using a rapid micro-induction protocol, buprenorphine/naloxone was administered for 3 days. On day 4, 300 mg BUP-XR was administered subcutaneously. Minimal withdrawal symptoms occurred, despite recent fentanyl use. DISCUSSION AND CONCLUSIONS: A rapid sublingual buprenorphine/naloxone micro-induction was successfully used to initiate BUP-XR, thereby eliminating the abstinence period prior to buprenorphine/naloxone administration, shortening the induction period, and minimizing withdrawal. SCIENTIFIC SIGNIFICANCE: This is the first reported case of using rapid micro-induction as a bridge to initiate BUP-XR. By reducing the length of induction to 4 days and minimizing withdrawal, this induction method can make BUP-XR more accessible to patients who would otherwise refuse the medication due to concerns of enduring withdrawal. (Am J Addict 2020;29:531-535).

In silico Complexes of Amino Acids and Diamondoids.

We report on the specific interaction of a small diamond-like molecule, known as diamondoid, with single amino-acids forming nano/bio molecular complexes. Using time-dependent density-functional theory calculations we have studied two different relative configurations of three prototypical amino acids, phenylalanine, tyrosine, and tryptophan, with the diamondoid. The optical and charge-transfer properties of these complexes exhibit amino acid and topology specific features which can be directly utilized for in the direction of novel biomolecule detection schemes.

Rapid micro-induction of buprenorphine/naloxone for opioid use disorder in an inpatient setting: A case series.

BACKGROUND AND OBJECTIVES: Buprenorphine/naloxone has been shown to be effective in the treatment of opioid use disorder. Due to its pharmacological properties, induction can be challenging, time-consuming, and result in sudden onset of withdrawal symptoms. METHODS: Retrospective case series (n = 2). RESULTS: Two patients with opioid use disorder were successfully started on buprenorphine/naloxone using a rapid micro-induction technique that did not cause precipitated withdrawal or require preceding cessation of other opioids. DISCUSSION AND CONCLUSIONS: These cases provide an alternative method for starting buprenorphine/naloxone that offers unique benefits compared to protocols previously described in the literature. SCIENTIFIC SIGNIFICANCE: This method can be used to minimize barriers to opioid agonist therapy. (Am J Addict 2019;28:262-265).

Methadone to buprenorphine/naloxone induction without withdrawal utilizing transdermal fentanyl bridge in an inpatient setting-Azar method.

BACKGROUND AND OBJECTIVES: Although buprenorphine/naloxone is widely recognized as first-line therapy for opioid use disorder, the requirement for moderate withdrawal prior to initiation in efforts to avoid precipitated withdrawal can be a barrier to its initiation. METHODS: We present a case utilizing transdermal fentanyl as a bridging treatment to eliminate withdrawal during the transition from methadone to buprenorphine/naloxone in a patient who had ongoing significant intravenous heroin use while on methadone. RESULTS: Patient was successfully transitioned from methadone to buprenorphine/naloxone without a period of withdrawal utilizing transdermal fentanyl as a bridge in an inpatient setting. DISCUSSION AND CONCLUSIONS: Our experience indicates a transdermal depot of fentanyl allows for slow release and elimination while buprenorphine doses are introduced during an induction without presence of withdrawal, as quantified by serial clinical opiate withdrawal score. SCIENTIFIC SIGNIFICANCE: This case report highlights ways to minimize barriers to induction of first-line opioid substitution therapy, buprenorphine/naloxone, by eliminating withdrawal during induction phase utilizing a fentanyl bridge within the limitations of a transdermal fentanyl bridge in an inpatient setting. (Am J Addict 2018;XX:1-4).

Time-dependent density functional theory study on direction-dependent electron and hole transfer processes in molecular systems.

We report on real-time time-dependent density functional theory calculations on direction-dependent electron and hole transfer processes in molecular systems. As a model system, we focus on α-sulfur. It is shown that time scale of the electron transfer process from a negatively charged S8 molecule to a neighboring neutral monomer is comparable to that of a strong infrared-active molecular vibrations of the dimer with one negatively charged monomer. This results in a strong coupling between the electrons and the nuclei motion which eventually leads to S8 ring opening before the electron transfer process is completed. The open-ring structure is found to be stable. The similar infrared-active peak in the case of hole transfer, however, is shown to be very weak and hence no significant scattering by the nuclei is possible. The presented approach to study the charge transfer processes in sulfur has direct applications in the increasingly growing research field of charge transport in molecular systems. © 2017 Wiley Periodicals, Inc.

Efficient "on-the-fly" calculation of Raman spectra from ab-initio molecular dynamics: Application to hydrophobic/hydrophilic solutes in bulk water.

We present a novel computational method to accurately calculate Raman spectra from first principles. Together with an extension of the second-generation Car-Parrinello method of Kühne et al. (Phys. Rev. Lett. 2007, 98, 066401) to propagate maximally localized Wannier functions together with the nuclei, a speed-up of one order of magnitude can be observed. This scheme thus allows to routinely calculate finite-temperature Raman spectra "on-the-fly" by means of ab-initio molecular dynamics simulations. To demonstrate the predictive power of this approach we investigate the effect of hydrophobic and hydrophilic solutes in water solution on the infrared and Raman spectra.

Drug use patterns associated with risk of non-adherence to antiretroviral therapy among HIV-positive illicit drug users in a Canadian setting: a longitudinal analysis.

BACKGROUND: Among people living with HIV/AIDS, illicit drug use is a risk for sub-optimal treatment outcomes. However, few studies have examined the relative contributions of different patterns of drug use on adherence to antiretroviral therapy (ART). We sought to estimate the effect of different types of illicit drug use on adherence in a setting of universal free HIV/AIDS treatment and care. METHODS: Using data from ongoing prospective cohorts of HIV-positive illicit drug users linked to comprehensive pharmacy dispensation records in Vancouver, Canada, we examined factors associated with ≥95% prescription refill adherence using generalized estimating equations (GEE) logistic regression. RESULTS: Between 1996 and 2013, 692 ART-exposed individuals were followed for a median of 42.7 months (Interquartile Range: 29.1-71.7). In multivariable GEE analyses, heroin injection (Adjusted Odds Ratio [AOR] = 0.75, 95% Confidence Interval [CI]: 0.66-0.85) as well as cocaine injection (AOR = 0.80, 95% CI: 0.72-0.90) were associated with lower likelihoods of optimal adherence. Methadone maintenance therapy (AOR = 1.88, 95% CI: 1.68-2.11) was associated with a greater likelihood of adherence. CONCLUSIONS: Periods of heroin and cocaine injection appeared to have the most deleterious impact upon antiretroviral adherence. The findings point to the need for improved access to treatment for heroin use disorder, particularly methadone, and highlight the need to identify strategies to support ART adherence among cocaine injectors.

Evidence for the existence of Li2S2 clusters in lithium-sulfur batteries: ab initio Raman spectroscopy simulation.

Using density functional theory calculations and ab initio molecular dynamics simulations we have studied the structures and the Raman spectra of Li2S4 clusters, which are believed to be the last polysulfide intermediates before the formation of Li2S2/Li2S during the discharge process in Li-S batteries. Raman spectra have been obtained using a new technique to estimate polarizabilities using Wannier functions. We have observed clear evidence of Li2S4→ Li2S2 transition by studying systematic changes in the simulated Raman spectra of (Li2S4)n, n = 1, 4, and 8 towards that of (Li2S2)8. Furthermore, we have shown that the dominant Raman peak of the Li2S2 cluster at ∼440 cm(-1) arises from sulfur-sulfur stretching mode. This peak has been experimentally observed in the discharged state of Li-S batteries and has also been attributed to the formation of Li2S2. We have also demonstrated that the transition is mainly due to the strong electrostatic interactions between Li2S4 monomers, which results in energy lowering by arranging the local Li(+δ)-S(-δ) dipole moments in an anti-parallel fashion.

48-hour Induction of Transdermal Buprenorphine to Extended-release Buprenorphine.

ABSTRACT: Buprenorphine extended-release (BUP-XR) provides sustained delivery of buprenorphine to control withdrawal and craving symptoms in the form of a monthly injectable and has been shown to improve health outcomes in patients with opioid use disorder. It is recommended that patients are stabilized with a transmucosal buprenorphine product, for at least 7 days per the product monograph; however, clinically, this timeline may be expedited. We report a case of a hospitalized patient with unregulated fentanyl use who underwent a successful transdermal buprenorphine induction for 48 hours to initiate BUP-XR with minimal levels of withdrawal and without precipitating opioid withdrawal. The approach described could provide a practical, patient-centered, accelerated induction strategy that, once independently validated, could considerably facilitate the use of BUP-XR.

Rapid induction of transdermal buprenorphine to subcutaneous extended-release buprenorphine for the treatment of opioid use disorder.

BACKGROUND: Buprenorphine is an effective and safe treatment for opioid use disorder, but the requirement for moderate opioid withdrawal symptoms to emerge prior to initiation is a significant treatment barrier. CASE PRESENTATION: We report on two cases of hospitalized patients with severe, active opioid use disorder, in which we initiated treatment with transdermal buprenorphine over 48 h, followed by the administration of a single dose of sublingual buprenorphine/naloxone and then extended-release subcutaneous buprenorphine. The patients did not experience precipitated withdrawal and only had mild withdrawal symptoms. CONCLUSIONS: This provides preliminary evidence for a rapid induction strategy that may improve tolerability, caregiver burden, and treatment retention as compared to previous induction strategies.

Systematic review on intentional non-medical fentanyl use among people who use drugs.

Objectives: Fentanyl is a highly potent opioid and has, until recently, been considered an unwanted contaminant in the street drug supply among people who use drugs (PWUD). However, it has become a drug of choice for an increasing number of individuals. This systematic review evaluated intentional non-medical fentanyl use among PWUD, specifically by summarizing demographic variance, reasons for use, and resulting patterns of use. Methods: The search strategy was developed with a combination of free text keywords and MeSH and non-MeSH keywords, and adapted with database-specific filters to Ovid MEDLINE, Embase, Web of Science, and PsychINFO. Studies included were human studies with intentional use of non-medical fentanyl or analogues in individuals older than 13. Only peer-reviewed original articles available in English were included. Results: The search resulted in 4437 studies after de-duplication, of which 132 were selected for full-text review. Out of 41 papers included, it was found that individuals who use fentanyl intentionally were more likely to be young, male, and White. They were also more likely to have experienced overdoses, and report injection drug use. There is evidence that fentanyl seeking behaviours are motivated by greater potency, delay of withdrawal, lower cost, and greater availability. Conclusions: Among PWUD, individuals who intentionally use fentanyl have severe substance use patterns, precarious living situations, and extensive overdose history. In response to the increasing number of individuals who use fentanyl, alternative treatment approaches need to be developed for more effective management of withdrawal and opioid use disorder. Systematic review registration: https://www.crd.york.ac.uk/prospero/, identifier CRD42021272111.

Developing A Rapid Transfer from Opioid Full Agonist to Buprenorphine: "Ultrarapid Micro-Dosing" Proof of Concept.

Buprenorphine/naloxone has been shown to be effective for treating opioid use disorder (OUD). However, the traditional method of induction requires a patient to be in moderate-to-severe withdrawal, which is challenging, time-consuming, and a common reason for leaving against medical advice. Induction strategies that minimize the severity and duration of patient discomfort while enabling patients to reach therapeutic doses during short hospital admissions can mitigate difficulties when inducing a patient on buprenorphine/naloxone. This case-series illustrates two patients with OUD using illicit fentanyl, who were successfully started on buprenorphine/naloxone using 24-hour and 6-hour micro-dosing induction protocol. During induction, the patients were up-titrated to a therapeutic dose through ultrarapid micro-dosing with ongoing use of short-acting opioids. Both patients reached therapeutic doses experiencing minimal levels of withdrawal. This case-series is a proof of concept for the use of a buprenorphine/naloxone ultrarapid micro-induction protocol for inpatients with OUD. By reducing the length of induction and precluding the need for withdrawal, this method offers several advantages over previously published inductions protocols and can improve the accessibility of buprenorphine/naloxone to patients with OUD.

Characterization of sulfur/carbon copolymer cathodes for Li-S batteries: a combined experimental and ab initio Raman spectroscopy study.

Optimization of lithium-sulfur batteries highly depends on exploring and characterizing new cathode materials. Sulfur/carbon copolymers have recently attracted much attention as an alternative class of cathodes to replace crystalline sulfur. In particular, poly(sulfur-n-1,3-diisopropenylbenzene) (S/DIB) has been under considerable experimental and theoretical investigations, promising a good performance in mitigating the so-called shuttle effect. Here, combining ab initio Raman spectroscopy simulations with experimental measurements, we show that S/DIB copolymers containing short and long sulfur chains are distinguishable based on their Raman activity in 400-500 cm-1. This frequency range corresponds to S-S stretching vibrations and is only observed in the Raman spectra of those copolymers with longer sulfur chains. The results reported in this study have direct applications in identification and characterization of general sulfur/carbon copolymers with different sulfur contents.

48-hour Induction of Transdermal Buprenorphine to Sublingual Buprenorphine/Naloxone: The IPPAS Method.

Buprenorphine is an effective medication for the treatment of opioid use disorder. However, the traditional method of buprenorphine induction requires a period of abstinence and the development of at least moderate withdrawal, which can be barriers in starting treatment. We present the case of a hospitalized patient with opioid use disorder using unregulated fentanyl, who underwent a transdermal buprenorphine induction over 48 hours to initiate sublingual buprenorphine/naloxone on the third day. The patient experienced minimal levels of withdrawal and did not experience precipitated withdrawal. The ease of use of this novel induction method over previously published induction protocols can greatly improve the accessibility of buprenorphine for patients and healthcare staff.