Electrocatalytic oxidation and amperometric determination of sulfasalazine using bimetal oxide nanoparticles-decorated graphene oxide composite modified glassy carbon electrode at neutral pH.

Cube-shaped samarium orthovanadate (SmVO4) nanoparticles were interconnected with a graphene oxide sheet (GOS) using a simple and eco-friendly method to generate a SmVO4@GOS nanocomposite. SmVO4 was characterized using various spectroscopic and microscopic techniques, which confirmed the wrapping of GOS around the SmVO4 nanoparticles. SmVO4@GOS was then used to modify a glassy carbon electrode (GCE), which was evaluated for its electrochemical performance toward the assay of sulfasalazine (SSZ), an antibiotic drug. Cyclic voltammetry and amperometry were both used for the assay of SSZ using the SmVO4@GOS-modified GCE at pH 7. The modified amperometric sensor is more sensitive, with a low detection limit (2.16 nM) and wide linear range of 20 nM-667 µM (Ag/AgCl). The electrochemical oxidation of SSZ was tested with blood serum and urine samples at physiological pH with recoveries in the range 96.1-98.6%. It indicates that the modified electrochemical sensor has good sensitivity and practical applicability toward SSZ detection. In the field of non-enzymatic sensors, SmVO4@GOS/GCE provides a highly promising performance. Therefore, the electrochemical sensors have capacity for extensive analytical applications in biomedical devices.

Objective Assessment of Laparoscopic Force and Psychomotor Skills in a Novel Virtual Reality-Based Haptic Simulator.

BACKGROUND: Most of the commercially available virtual reality-based laparoscopic simulators do not effectively evaluate combined psychomotor and force-based laparoscopic skills. Consequently, the lack of training on these critical skills leads to intraoperative errors. OBJECTIVES: To assess the effectiveness of the novel virtual reality-based simulator, this study analyzed the combined psychomotor (i.e., motion or movement) and force skills of residents and expert surgeons. The study also examined the effectiveness of real-time visual force feedback and tool motion during training. DESIGN: Bimanual fundamental (i.e., probing, pulling, sweeping, grasping, and twisting) and complex tasks (i.e., tissue dissection) were evaluated. In both tasks, visual feedback on applied force and tool motion were provided. The skills of the participants while performing the early tasks were assessed with and without visual feedback. Participants performed 5 repetitions of fundamental and complex tasks. Reaction force and instrument acceleration were used as metrics. SETTING: Surgical Gastroenterology, Government Stanley Medical College and Hospital; Institute of Surgical Gastroenterology, Madras Medical College and Rajiv Gandhi Government General Hospital. PARTICIPANTS: Residents (N = 25; postgraduates and surgeons with <2 years of laparoscopic surgery) and expert surgeons (N = 25; surgeons with >4 and ≤10 years of laparoscopic surgery). RESULTS: Residents applied large forces compared with expert surgeons and performed abrupt tool movements (p < 0.001). However, visual + haptic feedback improved the performance of residents (p < 0.001). In complex tasks, visual + haptic feedback did not influence the applied force of expert surgeons, but influenced their tool motion (p < 0.001). Furthermore, in complex tissue sweeping task, expert surgeons applied more force, but were within the tissue damage limits. In both groups, exertion of large forces and abrupt tool motion were observed during grasping, probing or pulling, and tissue sweeping maneuvers (p < 0.001). CONCLUSIONS: Modern day curriculum-based training should evaluate the skills of residents with robust force and psychomotor-based exercises for proficient laparoscopy. Visual feedback on force and motion during training has the potential to enhance the learning curve of residents.