A Descriptive analysis of urine drug screen results in patients with opioid use disorder managed in a primary care setting.

BACKGROUND: Urine drug screening (UDS) is commonly used as part of treatment for opioid use disorder (OUD), including treatment with buprenorphine-naloxone for OUD in a primary care setting. Very little is known about the value of UDS, the optimum screening frequency in general, or its specific use for buprenorphine treatment in primary care. To address this question, we thought that in a stable population receiving buprenorphine-naloxone in the primary care setting it would be useful to know how often UDS yielded expected and unexpected results. METHODS: We present a descriptive analysis of UDS results in patients treated with buprenorphine-naloxone for OUD in a primary care setting over a two-year period. An unexpected test result is: 1. A negative test for buprenorphine and/or 2. A positive test for opioids, methadone, cocaine and/or heroin. RESULTS: A total of 161 patients received care during the study period and a total of 2588 test results were analyzed from this population. We found that 64.4% of the patient population (n = 104 patients) demonstrated both treatment adherence (as measured by buprenorphine positive test results) and no apparent unexpected test findings, as defined by negative tests for opioids, methadone, cocaine and heroin. Of the 161 patients, 20 results were positive for opioids, 5 for methadone, 39 for heroin and 2 for cocaine. Analysis at the UDS level demonstrated that, of the 2588 test results, 38 (1.5%) results did not have buprenorphine. Of the 2588, 28 (1.1%) test results were positive for opioids, 8 (0.3%) were positive for methadone, 39 (1.5%) for cocaine and 2 (0.1%) for heroin. CONCLUSION: Given that the majority of patients in our study had expected urine results, it may be reasonable for less frequent urine testing in certain patients.

Dysprosium electrodeposition from a hexaalkylguanidinium-based ionic liquid.

The rare-earth element dysprosium (Dy) is an important additive that increases the magnetocrystalline anisotropy of neodymium magnets and additionally prevents from demagnetizing at high temperatures. Therefore, it is one of the most important elements for high-tech industries and is mainly used in permanent magnetic applications, for example in electric vehicles, industrial motors and direct-drive wind turbines. In an effort to develop a more efficient electrochemical technique for depositing Dy on Nd-magnets in contrast to commonly used costly physical vapor deposition, we investigated the electrochemical behavior of dysprosium(iii) trifluoromethanesulfonate in a custom-made guanidinium-based room-temperature ionic liquid (RTIL). We first examined the electrodeposition of Dy on an Au(111) model electrode. The investigation was carried out by means of cyclic voltammetry (CV) and X-ray photoelectron spectroscopy (XPS). The initial stages of metal deposition were followed by in situ scanning tunneling microscopy (STM). CV measurements revealed a large cathodic reduction peak, which corresponds to the growth of monoatomic high islands, based on STM images taken during the initial stages of deposition. XPS identified these deposited islands as dysprosium. A similar reduction peak was also observed on an Nd-Fe-B substrate, and positively identified as deposited Dy using XPS. Finally, we varied the concentration of the Dy precursor, electrolyte flow and temperature during Dy deposition and demonstrated that each of these parameters could be used to increase the thickness of the Dy deposit, suggesting that these parameters could be tuned simultaneously in a temperature-controlled flow cell to enhance the thickness of the Dy layer.

Titanium deposition from ionic liquids - appropriate choice of electrolyte and precursor.

In this study titanium isopropoxide was dissolved in 1-butyl-3-methyl-imidazolium bis(trifluoromethylsulfonyl)imide (BMITFSI) and further in a custom-made guanidinium-based ionic liquid (N11N11NpipGuaTFSI). Electrochemical investigations were carried out by means of cyclic voltammetry (CV) and the initial stages of metal deposition were followed by in situ scanning tunneling microscopy (STM). For BMITFSI we found one large cathodic reduction peak at a potential of -1.2 V vs. Pt, corresponding to the growth of monoatomic high islands. The obtained deposit was identified as elemental titanium by Auger Electron Spectroscopy (AES). Furthermore, we found a corresponding anodic peak at -0.3 V vs. Pt, which is associated with the dissolution of the islands. This observation leads to the assumption that titanium deposition from the imidazolium-based room-temperature ionic liquid (RTIL) proceeds in a one-step electron transfer. In contrast, for the guanidinium-based RTIL we found several peaks during titanium reduction and oxidation, which indicates a multi-step electron transfer in this alternative electrolyte.