Methods and systems for stimulating and monitoring electrogenic cells are described. Some systems for stimulating electrogenic cells are based on the injection of electric currents into the cells via electrodes connected to the cells. Such stimulators may comprise an impedance element having an input terminal and an output terminal coupled to an electrode, and a voltage follower coupled between the input terminal and the output terminal of the impedance element, the voltage follower being configured to maintain a substantially constant voltage between the input terminal and the output terminal of the impedance element. The impedance element may comprise one or more switched capacitors at least in some embodiments. In some embodiments, the voltage follower may be implemented using a source follower.

Disclosed are platforms to enable lower impedance electrode array, together with a miniaturized battery pack. Lower impedance can be achieved by different approaches, according to the invention, including surface modifications, preferably in nanoscale. Also disclosed are articles and control systems comprising medical implant neural stimulator devices, neural diagnosis tools, spinal cord and peripheral nerve stimulations, and cochlear implants. More particularly, the invention discloses means for reducing pains in human body, utilizing innovative components and systems comprising an epidural lead having multiple electrodes at a distal end, the electrodes being configured in an array and being selectable to provide either unilateral or bilateral neural stimulation. In an example, advanced spinal cord stimulation (SCS) electrodes having pre-designed novel, metallic or non-metallic nanostructured surface with desirable high-aspect-ratio nanopillar features for superior neural electrode functionality exhibiting significantly reduced electrical impedance are disclosed.

A biosensor includes an array of metal nanorods formed on a substrate. An electropolymerized conductor is formed over tops of a portion of the nanorods to form a reservoir between the electropolymerized conductor and the substrate. The electropolymerized conductor includes pores that open and close responsively to electrical signals applied to the nanorods. A dispensing material is loaded in the reservoir to be dispersed in accordance with open pores.

A nanowire probe sensor array including a substrate with a metal pattern thereon. An array of semiconductor vertical nanowire probes extends away from the substrate, and at least some of probes, and preferably all, are individually electrically addressed through the metal pattern. The metal pattern is insulated with dielectric, and base and stem portions of the nanowires are also preferably insulated. A fabrication process patterns metal connections on a substrate. A semiconductor substrate is bonded to the metal pattern. The semiconductor substrate is etched to form the neural nanowire probes that are bonded to the metal pattern. Dielectric is then deposited to insulate the metal pattern.

This disclosure relates to a glucose-sensing electrode including a nanoporous metal layer and an electrolyte ion-blocking layer formed over the nanoporous metal layer. The nanoporous metal layer is capable of oxidizing both glucose and maltose without an enzyme specific to glucose in the glucose-sensing electrode. The electrolyte ion-blocking layer is configured to inhibit Na.sup.+, K.sup.+, Ca.sup.2+, Cl.sup.−, PO.sub.4.sup.3− and CO.sub.3.sup.2− from diffusing toward the nanoporous metal layer such that there is a substantial discontinuity of a combined concentration of Na.sup.+, K.sup.+, Ca.sup.2+, Cl.sup.−, PO.sub.4.sup.3− and CO.sub.3.sup.2− between over and below the electrolyte ion-blocking layer.

The present invention belongs to the technical field of material fabrication, and particularly relates to an ultra-sensitive glucose sensor based on a graphene and carbon fiber substrate and a fabrication method thereof. The method includes fabricating a carbon fiber cloth with vertical graphene growth on a surface thereof, performing pretreatment to make the carbon fiber cloth hydrophilic, directly soaking the carbon fiber cloth in a PBS solution of glucose oxidase with the pH of 7.4, and then taking out and drying the carbon fiber cloth at room temperature to obtain a glucose sensor. According to the present invention, the lower limit of glucose detection reaches about 0.1 mM, and the glucose sensor also has multistage corresponding characteristics, so that different detection coefficients and capabilities can be achieved in different glucose concentration ranges. The application range and precision of the glucose sensor are greatly improved.

Personal diagnostic devices including diagnostic patches (bio-patches) and interactive medical bracelets (bio-bracelets) are provided with a skin/patch interface, at least one analysis layer, a signal processing layer, and a user output interface. Embodiments of the interactive diagnostic devices may include micro-fluidic circuits with reaction chambers, analysis chambers, mixing cambers, and various pre-disposed chemistries or reagents for performing a wide verity of tests by transdermal transport of blood or perspiration. Sample collection chambers for the fluidic circuit may include minimally invasive tubules that penetrate the skin surface to acquire blood samples from capillaries near the epidermis. Alternate implementations of the personal diagnostic device may be equipped with logic processing, input/output devices, acoustic microphones, cryogenic circuits, embedded processors, electrical control circuitry, and battery current sources or photovoltaic sources of electrical power.

Nanoparticle-fibrous membrane composites are provided as tunable interfacial scaffolds for flexible chemical sensors and biosensors by assembling gold nanoparticles (Au NPs) in a fibrous membrane. The gold nanoparticles are functionalized with organic, polymeric and/or biological molecules. The fibrous membranes may include different filter papers, with one example featuring a multilayered fibrous membrane consisting of a cellulose nanofiber (CN) top layer, an electrospun polyacrylonitrile (PAN) nanofibrous midlayer (or alternate material), and a nonwoven polyethylene terephthalate (PET) fibrous support layer, with the nanoparticles provided on the fibrous membranes through interparticle molecular/polymeric linkages and nanoparticle-nanofibrous interactions. Molecular linkers may be employed to tune hydrogen bonding and electrostatic and/or hydrophobic/hydrophilic interactions to provide sensor specificity to gases or liquids. The sensors act as chemiresistor-type sensors. A preferred implementation is a sweat sensor.

Presented herein are devices for collecting and/or channeling a biofluid (e.g., sweat, tears, saliva) and detecting and/or quantifying one or more biomarkers in the biofluid. The one or more biomarkers may include, for example, ions, salts thereof, hormones and/or steroids, proteins, metabolites and organic compounds. In certain embodiments, the devices described herein include a specially designed interface and a zero-energy micro pump that allow the device to be comfortably affixed directly to the skin of a user while biofluid is efficiently and non-invasively collected from the skin of the user. In certain embodiments, the biofluid collection and sensing device is housed on or in another wearable device, such as a wrist band or a smart watch. In certain embodiments, the devices described herein are disposable (e.g., after a certain period of use and/or wear the device can be disposed and replaced with a low-cost replacement).

Embodiments of the invention are directed to a system for detecting neurotransmitters. A non-limiting example of the system includes a porous electrode. A system can also include a pH sensor attached to the porous electrode, wherein the pH sensor includes a sensing electrode and a reference electrode. The system can also include electronic circuitry in communication with the pH sensor.