Deep-Tissue Optical Activation, Stimulation & Imaging System
The OASIS Implant, developed and produced by Mightex Systems, couples with a small implantable lens to enable the user to do imaging and patterned optical stimulation at any depth in brain tissue of behaving or anaesthetized animals.
How it works – GRIN lens implant and fiber coupling
This is achieved by coupling one end of a fiber bundle, containing an array of thousands of micro fibers, with an implanted GRIN lens. The other end of the fiber array bundle is coupled into the OASIS Implant platform, which accommodates the illumination and detection devices, as well as the filters and mirrors for directing outgoing and incoming light (see diagram below).
The GRIN lens supplied with the system is 500μm in diameter and 7mm in length (alternative dimensions available). Variations in depth of the implant enables you to address different structures and layers in the brain.
A fiber mount is fixed to the skull, just above the GRIN lens. This mount provides a stable structural interface between the fiber bundle and the GRIN lens. The fiber connection can be disengaged after each experiment, allowing for downtime between experiments and for experimenting on other animals using the same OASIS system.
The OASIS Platform, into which the other end of the fiber bundle couples, has two illumination ports, one or both of which can be connected to a Polygon400 spatial illuminator.
Spatial/Patterned illumination in vivo
The Polygon400 is a DMD-based patterned illuminator, which means it can project light down each fiber individually, allowing for complex spatial and temporal light patterns to be projected down the fiber tract.
The second port on the OASIS Implant Platform can be left empty, or it can be dedicated to a second Polygon400 or an LED Lightsource, allowing for great flexibility on the illumination end.
The detection side of the Implant Platform is equally flexible, since any c-mount CCD or sCMOS camera can be used for detection.
User-exchangeable filters and mirrors are also fitted in the Platform, and the lightpath can be adjusted mid-experiment using the three integrated filter sliders.
- Patterned deep-brain optogenetic stimulation
- Functional imaging, e.g. Calcium
- Widefield or patterned illumination fluorescence imaging
- Simultaneous or pseudo-simultaneous (if different colours or patterns are required) Patterned and/or wide-field optogenetic stimulation and imaging in freely behaving animals
The OASIS Implant coupling to the GRIN lens is light-weight and robust enough to allow for recordings in freely behaving mouse, and it’s been proven to be the ideal tool for recording calcium signals in deep-tissue, using GCaMP6, for example.
The system is also ideal for photoactivation or photoinhibition of neurons in the space near the lens’ focal plane – this can be done in a targeted way by only illuminating certain subsections of the field of view.
Because you have complete freedom with the illumination wavelength combination, and the additional benefit of using the patterned illumination, the system offers plenty of scope for other experiments, especially with the fast pace of development in the range and efficiency of opsins, fluorescent reporters and dyes.
This versatility is increased by the fact that you can use any camera for detecting the emitted light. This means that fast signals or low intensity signals are measurable, and you can use your preferred imaging software or the Mightex PolyScan software for acquisition and online analysis.
- This system can be used efficiently for simultaneous neural circuit manipulation and optical recording in freely behaving animals, which is not possible with any other system.
- Fibers are more flexible than the older head-mounted cameras and weigh much less (0.3g), and will not restrict animals or add to stress during experiments, in the end providing more reliable data.
- The OASIS fiber system can be used in conjunction with the Polygon400 to enhance all-optical interrogation into deep-brain tissues.
- The system provides sub-cellular resolution and high-quality deep-brain images and videos for qualitative and quantitative research.
- A single OASIS base station can be connected to more than one freely behaving animal, which is also not possible with other miniaturized microscopes or endoscopes.
- Modularity of this system and the flexibility of the software included, together with its state-of-the-art modern design ensures longevity of the system with lower costs than older versions.
Live Recording of the Striatum with the OASIS Implant. Mightex Systems, YouTube.
This video was taken from the striatum with the OASIS Implant through a 350um diameter fiber paired with a 500um diameter GRIN lens.
The light headmount required to use the OASIS implant enables a rodent to be freely-moving.
Can I use the OASIS system for freely moving behavioral tasks?
Can I program the spatial illumination to target cells of interest?
Can I demo an OASIS system before purchase?
OASIS Implant by Mightex Systems
The OASIS Implant by Mightex Systems enables deep-tissue optical activation, stimulation and imaging.