A microprobe for parallel optical and electrical recordings from single neurons in vivo

Abstract

Recording electrical activity from identified neurons in intact tissue is key to understanding their role in information processing. Recent fluorescence labeling techniques have opened new possibilities to combine electrophysiological recording with optical detection of individual neurons deep in brain tissue. For this purpose we developed dual-core fiberoptics-based microprobes, with an optical core to locally excite and collect fluorescence, and an electrolyte-filled hollow core for extracellular single unit electrophysiology. This design provides microprobes with tips < 10 μm, enabling analyses with single-cell optical resolution. We demonstrate combined electrical and optical detection of single fluorescent neurons in rats and mice. We combined electrical recordings and optical Ca²(+) measurements from single thalamic relay neurons in rats, and achieved detection and activation of single channelrhodopsin-expressing neurons in Thy1::ChR2-YFP transgenic mice. The microprobe expands possibilities for in vivo electrophysiological recording, providing parallel access to single-cell optical monitoring and control.

Metal‐Organic‐Framework‐Coated Optical Fibers as Light‐Triggered Drug Delivery Vehicles

“…It should be noted that this release rate is only for one optical fi ber and it is possible to make an array of drug-loaded optical fi bers for their intended application. [ 51,52 ] Figure 4 c shows a schematic illustration of an optical fi ber array. The fi ber bundle can be inserted into a specialized catheter (tube) for protection and then placed in proximity to the specifi ed tumorous area in the body.…”

Diode probes for spatiotemporal optical control of multiple neurons in freely moving animals

“…Indeed, diode probes enable experiments with behaving animals in which the number of illuminated and monitored brain areas exceeds the practical limit for the number of tethered fibers. These devices can be used to generate and monitor arbitrary spatiotemporal activity patterns in deep structures of the intact brain, a long-sought goal difficult to achieve with other recently developed optical stimulation techniques (Anikeeva et al 2011;Grossman et al 2010;LeChasseur et al 2011;Royer et al 2010;Wentz et al 2011). Moreover, as shown here, diode probes can be combined with real-time signal processing in freely moving animals to probe the spatial memory/navigation system, study short-term modifications, and generate unique network rhythms.…”

Fabrication and analysis of microfiber array platform for optogenetics with cellular resolution

“…Short term in vivo optical experiments have been conducted in mouse model, however, resist waveguide could be degraded with continuous exposure to blue light in long term experiment [6]. In contrast, optogenetic stimulation with single cell resolution using laser or light-emitting diode (LED) coupled fiber taper [7], micro LED array [8], digital micro mirror device (DMD)-based projector through a microscope [9], two-photon temporal focusing [10], etc, have also been developed. Silica fiber taper is the most common approach to illuminate light at the designate regions of brain.…”

“…Metal coating on fiber taper could not only provide electrical recording capability but also confine the spot size in emitting light. Recently, a microprobe for simultaneous optical and electrical recordings has been demonstrated for single cell optogenetics [7]. To achieve patterned optical stimulation, a tapered fiber array must be a long penetrating device resulting in unavoidable damages to the brain tissue during implantation [5].…”