Journal: Biomedicines

Article Title: Assessment of Chronic Multi-Electrode Spinal Cord Electrical Stimulation and Electromyography Platform in Non-Human Primates

doi: 10.3390/biomedicines14010166

Figure Lengend Snippet: Head plug design and general diagram of implantable devices. ( A – C ) Head plug prototype installed on an individual 3D model of a rhesus macaque skull, which was subsequently implanted. Designations: (1) substrate made of a composite biocompatible and osseointegrative material based on polyhydroxybutyrate and hydroxyapatite particles; (2) 12- and 16-pin plugs; (3) liner for positioning the plugs after installing the substrate—until fixation with light-curing composite; (4) head plug body with thread for the cover, made of polypropylene; (5) self-tapping screws made of titanium alloy for fixing the structure to the skull; (6) sealed cover with thread and locking screw; ( D – F ) stages of head plug installation during surgery on a rhesus macaque; ( G ) 3D models of head plug elements in a customized design; ( H ) general diagram of the implantable system for simultaneous recording of motor activity and spinal cord stimulation; ( I ) diagram of connectors for head plugs.

Article Snippet: To connect the EMG equipment and stimulators to the implantable electrodes, head plugs were manufactured, including connectors (one 12-pin and one 16-pin, A22004-001 (MCP-12-SS), and A22032-001 (MCP-16-SS), Omnetics Connector Corp., Minneapolis, MN, USA) and microcables in multi-strand steel insulation (AS632, Cooner Wire, Chatsworth, CA, USA) as electrical conductors ( A–C).

Techniques: Activity Assay

Journal: Scientific Reports

Article Title: Novel microwire-based biosensor probe for simultaneous real-time measurement of glutamate and GABA dynamics in vitro and in vivo

doi: 10.1038/s41598-020-69636-1

Figure Lengend Snippet: Assembled microwire biosensor. ( A ) The biosensor consists of three surface-modified platinum microwires that are packaged using heat shrink tubing (*). This simple and scalable packaging ensures close packing at the sensor side of the microwires and allows them to terminate in a single plane perpendicular to the sensor axis. Microwires were connected to pins of a Mill-Max connector using heat shrink tubing (dagger). This device was used for brain slice recordings. Inset. View of the distal, recording end of the biosensor. Scale bar denotes 100 µm. The ends of the coated microwires appear as dark circular areas surrounded by light-colored insulation; heat shrink tubing surrounds all three microwires (*). ( B ) Photograph of microwire biosensors for in vivo recording (left) and ex vivo recordings (right). For in vivo recordings, the microwire bundle at the distal end of the device is inserted into a permanently implanted cannula (not shown), and the translucent plastic Luer lock fitting is attached to the implanted cannula (Luer lock connector at bottom of fitting). A ground-connector wire runs through the fitting to connect a previously-implanted ground wire to the recording system. One end of the wire is looped inside the lumen of the Luer lock fitting in the screw connector (bottom of fitting) while the other end exits the top of the fitting, near the Mill-Max pins (single wire terminating with a pin connector). The loop of wire makes a connection with a matched loop of wire in the cannula connector. For in vitro and ex vivo recording, the device does not have a Luer lock fitting. For experiments, it is held in a micromanipulator by its Mill-Max connector. A separate ground wire (not shown) is placed away from the biosensor array.

Article Snippet: To form the microwire biosensor, we tightly wrapped the uncoated, exposed “other” end of the Pt wire of each biosensor around a 500-μm diameter, gold-coated Mill-Max connection pin to form a secure physical and electrical contact.

Techniques: Modification, Slice Preparation, In Vivo, Ex Vivo, In Vitro