Biomimetic urine flow control can preserve bladder function in patients with indwelling catheterization.

For patients with long-term indwelling catheterization, bladder function will be affected. It is necessary to explore whether biomimetic urine flow control (BUFC) can improve bladder function in patients undergoing indwelling catheterization. A retrospective, data-only, cohort study was carried out. The patients admitted to the intensive care unit, who had retained catheter and been continuously using a urodynamic monitoring system for over 30 days were selected. They were divided into 2 groups based on whether they were using BUFC function. The urodynamic monitoring data of the 2 groups were compared and analyzed. A total of 30 patients were included in the final analysis, including 15 in the BUFC group and 15 in the unobstructed group. The Urinary Volume and maximal urinary flow rate of the unobstructed group showed a continuous downward trend, while the BUFC group remained stable, and there was a statistical difference (P < .05) between the 2 groups since day 20. The bladder ultrasound imaging showed that the bladder volume of the BUFC group did not decrease significantly on the 30th day. BUFC technology, which provided by a urodynamic monitoring system, has potential protective effects of the bladder function after indwelling catheterization.

A label-free electrochemical impedance immunosensor based on AuNPs/PAMAM-MWCNT-Chi nanocomposite modified glassy carbon electrode for detection of Salmonella typhimurium in milk.

A sensitive and stable label-free electrochemical impedance immunosensor for the detection of Salmonella typhimurium was developed by immobilising anti-Salmonella antibodies onto the gold nanoparticles and poly(amidoamine)-multiwalled carbon nanotubes-chitosan nanocomposite film modified glassy carbon electrode (AuNPs/PAMAM-MWCNT-Chi/GCE). Electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV) were used to verify the stepwise assembly of the immunosensor. Co-addition of MWCNT, PAMAM and AuNPs greatly enhanced the sensitivity of the immunosensor. The immobilisation of antibodies and the binding of Salmonella cells to the modified electrode increased the electron-transfer resistance (Ret), which was directly measured with EIS using [Fe(CN)6](3-/4-) as a redox probe. A linear relationship of Ret and Salmonella concentration was obtained in the Salmonella concentration range of 1.0×10(3) to 1.0×10(7) CFU mL(-1) with a detection limit of 5.0×10(2) CFU mL(-1). Additionally, the proposed method was successfully applied to determine S. typhimurium content in milk samples with satisfactory results.

Electrochemical determination of theophylline in foodstuff, tea and soft drinks based on urchin-like CdSe microparticles modified glassy carbon electrode.

A simply electrochemical method based on CdSe microparticles modified glassy carbon electrode (GCE) was developed to determine theophylline using cyclic voltammetry and differential pulse voltammetry. Theophylline showed a well-defined oxidation peak at the fabricated electrode in phosphate buffer solution and the oxidation peak current is much higher than that at the bare GCE, indicating that CdSe can effectively improve the oxidation of theophylline. Several effect factors on theophylline determination were optimised, such as CdSe amount, solution pH, scan rate and accumulation time. Under the optimal conditions, the oxidation peak current of theophylline was proportional to its concentration in the range of 1.0-40 and 40-700 µM with a correlation coefficient of 0.9974 and 0.9956, respectively. The limit of detection was estimated to be 0.4 µM (S/N=3). The developed method showed good reproducibility and excellent selectivity. The fabricated electrode was successfully used to determine theophylline in tea, carbonated cola drink, fruit juice drink, fermented milk drink and preserved fruit with acceptable recovery.

Nonenzymatic amperometric organic peroxide sensor based on nano-cobalt phthalocyanine loaded functionalized graphene film.

An enzyme-free amperometric method was established for the electrochemical reduction tert-butyl hydroperoxide (TBHP) on the utilization of nano-cobalt phthalocyanine (CoPc) loaded functionalized graphene (FGR) and to create a highly responsive organic peroxide sensor. FGR was synthesized with a simple and fast method of electrolysis with potassium hexafluorophosphate (KPF(6)) solution as electrolyte under the static current of 0.2A. In the present work, FGR was dispersed in the solution of CoPc to fabricate chemical modified electrode to detect TBHP. The electro-reduction of TBHP can be catalyzed by FGR-CoPc, which has an excellent electrocatalytical activity due to the synergistic effect of the FGR with CoPc. The sensor can be applied to the quantification of TBHP with a linear range covering from 0.0260 to 4.81 mM, a high sensitivity of 13.64 A M(-1), and a low detection limit of 5 µM. This proposed sensor was designed as a simple, robust, and cheap analytical device for the determination of TBHP in body lotion.