Development of a voltammetric assay, using screen-printed electrodes, for clonazepam and its application to beverage and serum samples

© 2015 Elsevier B.V. All rights reserved. This paper describes the development of an electrochemical assay based on screen-printed carbon sensors for the determination of clonazepam in serum and in wine. The cyclic voltammetric behaviour of the drug was investigated and the effects of pH and scan rate on the peak current and peak potential determined. Two reduction peaks were recorded on the initial negative going scan, which were considered to result from the 2e-, 2 H+ reduction of the 4,5-azomethine and from the 4e-, 4 H+ reduction of the 7-NO2 to a hydroxylamine. On the return positive going scan an oxidation peak was seen, which was considered to result from the 2e-, 2 H+ oxidation (O1) of the hydroxylamine to the corresponding nitroso species. At pH 11 the solution of clonazepam was found to turn from clear to yellow in colour and the voltammetric signal of the O1 oxidation process was found to be adsorptive in nature, this was exploited in the development of an adsorptive stripping voltammetric assay. Experimental conditions were then optimised for the differential pulse adsorptive voltammetric measurement of clonazepam in wine and serum samples. It was shown that these analyses could be performed on only 100 μL of sample which was deposited on the sensor surface. Mean recoveries of 79.53% (%CV=9.88%) and 88.22% (%CV=14.1%) were calculated for wine fortified with 3.16 μg/mL and serum fortified with 12.6 μg/mL

Has Behavioral Science Tumbled Through the Biological Looking Glass? Will Brief, Evidence-Based Training Return It From the Rabbit Hole?

Time constraints and professional demands leave practicing professionals unlikely to enroll in extended training such as a semester-long graduate course. Thus, the three-hour continuing education format has become a standard for those in practice. One may ask what sorts of training strategies optimize that format. To explore that, a three hour training program for seventy-six practicing mental health professionals, most of whom self-identified as psychologists, was devised. It made use of primarily antecedent techniques that have been shown to bring about changed perceptions on a number of topics. Content focused on two areas of importance to behavior analysts, the culture’s increasing acceptance of the biological causation model of disorders such as attentiondeficit hyperactivity disorder (ADHD), unipolar depression, anxiety disorders, and schizophrenia, and the field’s increasing reliance on medications, often to the exclusion of behavioral methods. Pre-post assessment showed that participants had changed their thinking regarding the two content areas. The authors caution that participants’ changed opinions may serve as setting events to changes in practice, but those changes are verbal. One must not assume changes in practice techniques will automatically occur

Onset of activity and time to response on individual CAPS-SX17 items in patients treated for post-traumatic stress disorder with venlafaxine ER: a pooled analysis

This pooled analysis of data from two randomized, placebo-controlled trials of venlafaxine extended release (ER) assessed onset of activity and time to response on the 17 symptoms of post-traumatic stress disorder (PTSD) listed in DSM-IV and measured by the 17-item Clinician-Administered PTSD Scale (CAPS-SX17). The intent-to-treat (ITT) population comprised 687 patients (placebo, n=347; venlafaxine ER, n=340). Significant (p<0.05) separation between venlafaxine ER and placebo was observed on most CAPS-SX17 items, with earliest onset of activity and response (week 2) on items 5 (physiological reactivity on exposure to cues) and 14 (irritability or anger outbursts), and (week 4) items 1 (intrusive recollections) and 4 (psychological distress at exposure to cues). Onset of activity and response occurred later (generally, weeks 6-8) on items 9 (diminished interest/participation in activities), 10 (detachment or estrangement), 11 (restricted range of affect), 12 (sense of foreshortened future), all associated with numbing, 15 (difficulty concentrating), 16 (hypervigilance), 17 (exaggerated startle response), associated with hyperarousal, and 6 (avoidance of thoughts/feelings or conversations). Significant differences between venlafaxine ER and placebo were largely absent throughout the treatment period and at the primary week-12 end-point for items 2 (distressing dreams), 7 (avoidance of activities, places or people), 8 (inability to recall important aspect of trauma) and 13 (difficulty falling/staying asleep). These results indicate that symptoms of physiological reactivity and psychological distress in response to cues, and irritability/anger outbursts show early and robust improvement with venlafaxine ER treatment, while symptoms of numbing and hyperarousal take longer. The early and persistent effect of venlafaxine ER over placebo on anger/irritability is noteworthy in view of the clinical significance of these symptoms in PTSD