Laser-scribing fabrication of a disposable electrochemical device for forensic detection of crime facilitating drugs in beverage samples

A portable and disposable laser-scribed graphene (LSG) device was fabricated on polyetherimide (PEI) substrate for electrochemical detection of benzodiazepines (BZ) drugs such as diazepam (DZ) and midazolam (MZ) in commercial beverage samples. Morphological characterizations of the LSG material recorded by scanning electron microscopy (SEM) revealed the porous nature of the proposed electrochemical device, which contributed to the enhancement of the electroactive area. Besides, the structural and electrochemical characterizations performed by Raman spectroscopy, cyclic voltammetry (CV), and electrochemical impedance spectroscopy (EIS) measurements revealed that the PEI-LSG material presents highly disordered graphene-like structures and high electron transfer features, respectively. The electrochemical detection of DZ and MZ was carried out by Square Wave Voltammetry (SWV), whose analytical curves exhibited two linear intervals in concentrations ranging from 2.5 μmol L^-1 to 25.0 μmol L^-1 and from 25.0 μmol L^-1 to 100.0 μmol L^-1 for both BZ. We obtained limits of detection (LOD) and quantification (LOQ) of 0.66 and 2.18 μmol L^-1 for DZ and 0.61 μmol L^-1 and 2.01 μmol L^-1 for MZ, respectively. The developed sensor was applied to detect DZ and MZ in commercial beverages such as juice, whisky, and sugarcane spirit samples to mimic potential forensic evidence of drug-facilitated crimes. The recoveries ranged from 97.1% to 117.2% for DZ and from 92.2% to 114.3% for MZ. In addition, the proposed method presented high manufacturing reproducibility (relative standard deviation (RSD) = 2.18% for DZ and RSD = 3.82% for MZ, n = 8 sensors) and adequate selectivity, highlighting the potential of PEI-LSG sensor as an excellent alternative method for forensic detection of crime facilitating drugs in commercial beverage samples.

Non-traditional administration of remifentanil in an experimental setting

Remifentanil is ultrashort-acting opioid with a unique pharmacokinetic profile. It is used exclusively intravenously. While considering its rapid onset of action and other pharmacokinetic properties, we decided to assess its effects following administration via non-traditional routes. Rabbits (n=10 per each group) were randomized into six groups: remifentanil 1 microg/kg and 3 microg/kg IM, 5.0 and 10.0 microg/kg conjunctivally, and 10 microg/kg and 25.0 microg/kg intranasally. Sedating effects were assessed via a loss of the righting reflex. Secondary, mean arterial blood pressure, arterial oxygen saturation of hemoglobin, and pulse rate was monitored in all rabbits. Non-traditional routes of administration were shown to provide a rapid onset of action as well as fast recovery. Importantly, the administration of remifentanil did not result in any deterioration of cardiovascular functions.

Plasma concentrations and sedative effects of a dexmedetomidine, midazolam, and butorphanol combination after transnasal administration in healthy rabbits

Plasma concentrations of dexmedetomidine (D = 0.1 mg/kg), midazolam (M = 2 mg/kg), and butorphanol (B = 0.4 mg/kg) were analyzed by liquid chromatography-mass spectrometry (LC-MS/MS) after their simultaneous (DMB) transnasal (TN) administration to healthy rabbits. Time-dependent changes in sedation and antinociception were evaluated by measuring a sedation score based on rabbit's posture, loss of the righting, palpebral and pedal withdrawal reflexes and by instrumental monitoring of rectal temperature, heart rate, arterial blood pressure, pulse-oximetry, and capnometry. The peak plasma concentration (Cmax ) of each drug was reached within 5 min (Tmax ) from DMB-TN administration along with deep sedation and analgesia. Such effects subsided after 45 min into a moderate sedation and analgesia lasting for additional 15 min. All rabbits awakened spontaneously and uneventfully 90 min after DMB-TN administration. During the anesthetic procedure, arterial blood pressure markedly decreased and respiratory depression ensued requiring oxygen supplementation. The results of this study show that all three molecules of the DMB combination were absorbed through the TN route, inducing deep sedation and analgesia suitable for minor surgical procedures. Such combination should be used with caution in rabbits bearing cardiovascular or respiratory diseases because of its ability to induce hypotension and respiratory depression.

Comparative pharmacokinetics and bioavailability of intranasal and rectal midazolam formulations relative to buccal administration in rabbits

The rectal and intranasal formulations under current development demonstrated comparative potential for administering midazolam in treating seizures in a medical emergency service.