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The biochemical processes in the body, including wound healing, are influenced by pH. When skin is damaged, in the inflammation phase, the pH of the skin is under pH 6.0, and in the granulation and spontaneous reepithelization phase, the pH of the skin oscillates between 6 and 8. If there is a frequent change in the wound dressing, it will make the damage to the skin hard to cure, especially for chronic wounds. In this article, we design and implement a highly sensitive micro-electro-mechanical-system (MEMS) cavity-based pH image biosensor of a $100\times100$ array with an integrated readout circuit in a CMOS bulk technology. Based on the proposed pH fringing electrical field model, we predict and optimize the performance of the proposed sensor pattern with cavity structure for operation frequency and various pH ions. The proposed pH biosensor with MEMS cavity structure exhibits a high sensitivity of 201 mV/pH, low drift voltage over time of 2.08 mV, a fast response time of 5 s, high precise repetition of 98.9%, and a pH image of 20 frame rate/s. Since the sensor is a $100\times100$ array, it displays a detailed change in the pH image of wound exudate to identify the inflammation stage under pH 6 or spontaneous reepithelization above pH 6 to indicate the need to change the dressing, reducing the clinician’s wasted resources on frequency change of wound dressings. [ABSTRACT FROM AUTHOR]

Cancer is a devastating and life-threatening disease. It is the second leading cause of death worldwide after heart diseases. While science has significantly advanced to improve the treatment outcome and quality of life in cancer patients, there are still many issues with the current therapies, such as toxicity and the development of resistance to treatment. Among the novel tools to overcome these limitations is nonthermal plasma (NTP) and its treatment regimens. Recent progress in NTP devices with ion temperatures close to room temperature demonstrated significant potential in cancer therapy. NTP devices provide a unique combination of reactive oxygen species (ROS), reactive nitrogen species (RNS), photons, and electric fields that exhibit desirable properties of triggering cell death pathways, selectively for cancer cells. While in principle NTP is nonnecrotic and gentle to the tissue, but reactive oxygen and nitrogen species (RONS)-triggered tumor cell death exhibited to have pro-immunogenic properties. Many in vitro and in vivo experiments have demonstrated antitumor effects of direct NTP, synergistic applications of NTP with anticancer drugs/treatments, and plasma-conditioned medium (PCM) applications against a variety of cancer cells. The latest results and findings in this field are the subject of this review along with a brief lay-reader-explanation of cancer and immunology. In this review, initially, we give an overview of the literature that deals with studies on the use of NTP for cancer treatment. Subsequently, we present typical results from that literature to illustrate the advances of NTP in oncology. Finally, we discuss some challenges and future scopes offered by NTP for cancer treatment. [ABSTRACT FROM AUTHOR]

This paper presents a Chitosan-Graphene Oxide (CS-GO)-based array of ultra-thin biosensors with gold (Au)-based microgap ($60~\mu \text{m}$) electrode. The cross-linked GO is shown to improve the stability of chitosan substrate in aqueous medium and compatibility with microfabrication steps. The sensor patch has been evaluated for label-free monitoring by immobilizing the CS-GO surface with human dermal fibroblast (HDF) cells. The cyclic voltammetry (CV) of HDF cell immobilized CS-GO surface show quasi-reversible nature with a characteristic cathodic peak at +300 mV and anodic peak at −300 mV. Both peaks are stable and repeatable up to 50-scan cycle without any potential shift. The device shows a steady-state peak enhancement (1.923-11.195nA) during the DHF cell growth period (0-96h). The redox peak enhancement correlates with the cell proliferation rates over time, indicating that it could be employed for investigation of the cyto-physiological state against any endo and exogenous stimulation. In addition, the developed sensor-patch was used to detect a wide range of glucose from $1~\mu \text{M}$ to 20mM in vitro with a sensitivity of $0.17~\mu \text{A}$ /mM. Considering these, the presented sensor-patch has a great potential for the detection of glucose level, cell-health proliferation rate at the wound site, and diabetic wound monitoring applications. [ABSTRACT FROM AUTHOR]

The aim of this experiment is to enhance selected species in atmospheric pressure plasma jet (APPJ) that might be helpful for the wound healing purpose and to test the performance using basic diagnosis in plasma-treated liquid. A homemade APPJ device is driven by sinusoidal voltage with a excitation frequency of 25 kHz. Argon with admixture of small percentage of nitrogen, oxygen, and water vapor was selected to be carrier gas as the main sources of reactive species. Discharge power consumption is calculated by two approaches. Reactive oxygen species and reactive nitrogen species in the excited states are characterized by optical emission spectroscopy (OES). Excitation temperature $T_{\mathrm {exc}}$ in argon plasmas is calculated to estimate the electron energy distribution. The results show that argon plasmas with small addition of nitrogen and oxygen in this jet configuration are more efficient to generate desired reactive species in terms of OES diagnosis and liquid acidification. Moreover, the distinct efficiency of liquid acidification between direct and indirect plasma treatment of liquid has also been observed. [ABSTRACT FROM AUTHOR]

In this letter, we demonstrate an inkjet-printed WO3-based pH sensor array using WO3/Ag and Ag/AgCl as working and reference electrodes, respectively, on a flexible polyimide substrate. Pre-treated by Tollen’s reagent, the printed Ag lines as sensor interconnects can exhibit a denser microstructure with lower electrical resistivity. As a result, the WO3 nanoparticles can be well printed and sintered at 120 °C on the Ag lines as the working electrodes of the pH sensors. Experimental results show the sensitivity of the pH sensor to be as high as −24.4 mV/pH. The array comprising six pH sensors shows potential for real-time 2-D pH sensing applications. [ABSTRACT FROM PUBLISHER]

Alkali-free glasses, which exhibit high energy storage densities ( \sim 35 J/cc), present a unique opportunity to couple high temperature stability with high breakdown strength, and thus provide an avenue for capacitor applications with stringent temperature and power requirements. Realizing the potential of these materials in kilovolt class capacitors with >1 J/cc recoverable energy density requires novel packaging strategies that incorporate these extremely fragile dielectrics. In this paper, we demonstrate the feasibility of fabricating wound capacitors using 50- \mu \text{m} -thick glass. Two capacitors were fabricated from 2.8-m-long ribbons of thin (50 \mu \text{m}$ ) glass wound into 125–140-mm-diameter spools. The capacitors exhibit a capacitance of 70–75 nF with loss tangents below 1%. The wound capacitors can operate up to 1 kV and show excellent temperature stability to 150 °C. By improving the end terminations, the self-resonance can be shifted to above 1 MHz, indicating that these materials may be useful for pulsed power applications with microsecond discharge times. [ABSTRACT FROM PUBLISHER]

Nano-patterned oxidized porous silicon (PS) substrates are topographically biocompatible to provide in vitro environment for improved understanding of in vivo wound healing behavior. But the wound healing studies reported on various featured substrates are mainly based on time lapse microscopy coupled with fluorescent labeling. This study is the first attempt to perform continuous monitoring of wound healing phenomena using PS substrates with two pore morphologies by means of impedance measurement. A distributed electrical model has been developed for the PS substrates to extract the cell migration rate, proliferation rate, and time-dependent coverage of cell free area. It has been observed from impedance measurements and from model that the wound closure is faster on 50 nm pores followed by 500 nm pores and planar ECIS substrates. This has been qualitatively explained from the extracted time-dependent cell–cell and cell-substrate interaction parameters using a well-known mechanical model of wound healing process. The electrical readings have been closely correlated with scanning electron microscopy (SEM) and optical microscopy images. Thus, the impedance spectroscopy method coupled with the proposed theoretical framework can provide information about the underlying mechanisms of wound regeneration on nano-patterned substrates in a non-invasive manner. [ABSTRACT FROM PUBLISHER]

We evaluated a nonthermal plasma jet for a respective use to prevent infections from bacteria and yeasts. The plasma jet is generated from the flow of ambient air with 8 slm through a microhollow cathode discharge assembly that is operated with a direct current of 30 mA. With these parameters, the temperature in the jet reaches 43 ^\circ\C at 10 mm from the discharge. Agar plates that were inoculated with Staphylococcus aureus, Pseudomonas aeruginosa, Acinetobacter baumannii, and Candida kefyr were treated at this distance, moving the plates through the jet in a meander that covered a 2 cm by 2 cm area. Different exposure times were realized by changing the speed of the movement and adjusting the distance between consecutive passes. S. aureus was most responsive to the exposure with a reduction in the number of colony forming units of 5.5 log steps in 40 s. All other microorganisms show a more gradual inactivation with exposure times. For all bacteria, a clearing of the treated area is achieved in about 2.5–3.5 min, corresponding to log-reduction factors of 5.5–6.5. Complete inactivation of the yeast requires about 7 min. Both S. aureus and C. kefyr show considerable inactivation also outside the immediate treatment area, while P. aeruginosa and A. baumannii do not. We conclude that differences in the morphologies of the membrane structures are responsible for the diverging results, together with a targeted response to different agents provided with the plasma jet. For the gram negative bacteria, we hold short-lived agents, acting across a short range, responsible, while for the other microorganisms, longer lived species seem more important. Our measurements show that neither heat, ultraviolet radiation, nor the generation of ozone can be responsible for the observed results. The most prominent long lived reaction product found is nitric oxide, which, by itself or through induced chemical reactions, might affect cell viability. [ABSTRACT FROM PUBLISHER]

The design and the electric and emission characteristics of a handheld air plasma spray are presented. The plasma is generated by 60-Hz periodic discharges between two concentrically cylindrical electrodes. A ring magnet is used to rotate arc discharges, which sprays outward by an airflow. The rotation of arc discharges keeps the generated plasma in nonequilibrium state and at relatively low temperature (\sim \!\!55\ ^\circ\C). The plasma effluent still contains high-energy electrons which dissociate molecular oxygen into atomic oxygen. The emission spectroscopy of the plasma plume reveals that the plasma effluent, which carries abundant atomic oxygen, extends from the cap of the plasma spray about 25 mm. Using pigs as the animal model, in vivo tests of stopping wound bleeding and postoperative observation of wound healing by this air plasma spray were performed. The results show that the bleeding from a cut to an ear artery is stopped swiftly; this air plasma spray also shortens wound healing time to about half (from 14 days to 8 days) after stopping the bleeding of a cross-cut wound in the ham area. [ABSTRACT FROM AUTHOR]