for TREC Microdrives or for other Applications
The TREC MicroInjection System (MIS) is a product combination consisting of a multichannel microelectrode manipulator “System Eckhorn” equipped with microelectrodes and micropipettes and a precision microinjection pump. Both, the microelectrode manipulator and the microinjection pump are software controlled via the same graphical user interface (gui). The use of the Thomas MIS in a non human primate injection/recording experiment was described in a video publication by Veith et al. in 2016 (Veith VK, Quigley C, & Treue S. A Pressure Injection System for Investigating the Neuropharmacology of Information Processing in Awake Behaving Macaque Monkey Cortex. Journal of Visualized Experiments (jove) 109[e53724], 1-8. 2016)
The MicroInjection System (MIS) is also available in a stand alone version. In this case the user can combine the MIS with other microelectrode recording devices. The stand alone MIS is delivered with a microprocessor motor control unit, a microinjection pump and a computer software.
- Software controlled microinjection
- Supports thin microinjection pipettes (OD=100-120µm),
- Minimized tissue damage by thin pipettes
- Syringe pump system
- Use with TREC Microdrive systems (simultaneous injection/recording)
- Same software for control of pump and microdrive
- Stand-alone microinjection system available
- Multichannel injection system available
- Quartz glass and metal pipettes available
Dimensions and Weight
|Supply Voltage (V)||12V AC|
|Power Consumption (W)||1,2W|
Supported syringes (piston range app. 36mm)
Injection rates (supported by the software)
|Syringe Type I||1…60 nl/s|
|Syringe Type III||5…260 nl/s|
|Syringe Type IV||5…700 nl/s|
The Thomas microinjection system (MIS) is a syringe based pressure injection system for neurophysiological and neuropharmacological applications (figure 1).
The MIS is available in a version to be used with Thomas multielectrode microdrive systems such as the “Eckhorn Matrix” or the “Mini Matrix”. Furthermore we offer the MIS as a stand-alone version for other applications.
MIS with Thomas Microdrive system
This version of the MIS allows to connect the MIS microinjection pump to the motor control unit of the Microdrive system (MCU-2) and to use one software to control electrode and pipette positioning and the drug injection rate.
The configuration shown in figure 2 allows drug injection in the direct vicinity of the recording site. The Thomas microdrive can place several recording microelectrodes (OD=80µm) and a microinjection cannula (OD=115-120µm) with high precision in the animal´s brain. The software of the microdrive controls the positioning of the recording electrodes and the injection cannula as well as the drug injection rate of the microinjection pump. The pressure injection of neuropharmacological substances during single-cell recording with the Thomas MIS and a Tetrode Mini Matrix system in an awake, behaving macaque monkey was published by Veith et al. in 2016 . The authors demonstrate the combination of acute single-cell recordings with the injection of neuropharmacological agents in the direct vicinity of the recording electrodes. A video shows the preparation of the pressure injection/recording system, including preparation of the substance to be injected. The authors show a rhesus monkey performing a visual attention task and the procedure of single-unit recording with block-wise pharmacological manipulations.
MIS stand-alone version
Beside the use of the MIS with a Thomas Microdrive system we also offer this device in a stand-alone solution (figure 3). This stand-alone version consists of a microinjection pump, a microprocessor motor control unit and a computer software that controls the injection pump. For recording the neural response any other neurophysiological recording equipment can be used. We can deliver quartz glass or metal microinjection pipettes.
Comparison to alternative methods
Veith et al.  have compared the MIS and the Mini Matrix system with other microinjection systems. The authors stated that the system used in their application showed clear advantages compared to other pressure injection systems. They found that one strong advantage is the diameter of the micropipette (approximately 100 µm), which is half the size of other available probes and therefore minimizes neural tissue damage. In contrast to previous designs, the current system employs spatially separated recording electrodes and micropipette. The system described in the publication allowed independent depth changes of electrodes and pipette, thus permitting variable relative distances within a recording session. The authors stated that no compromise regarding recording quality needs to be made, as the MIS is an extension of the established Thomas recording device. While only one micropipette and thus one substance was used in the described application, it is possible to inject several substances within one experimental procedure. To achieve this, several micropipettes can be loaded into separate Mini Matrix guide tubes and connected to syringes mounted in individual injection pumps of the MIS. Finally, the authors reported that controlling the system was easy, as only one computer program was needed to advance the electrodes and micropipette, and to perform the pressure injection during the experiment.
Figure 2: Block diagram of the MIS-03 used with a Thomas 5 electrode Mini Matrix system in an injection/recording configuration. This system allows to place one injection cannula and 4 microelectrodes with high spatial resolution in the brain, to inject a drug in the direct vicinity of the recording electrodes and to record the neural response with up to 4 microelectrodes simultaneously. The trigger output of the injection system is optional available and allows to record the time stamps for start and stop of the drug injection simultaneously with neural response.
Vera K. Veith, Cliodhna Quigley, Stefan Treue, Jove, 3/14/2016, Issue 109; doi: 10.3791/53724
 Vera K. Veith, Cliodhna Quigley, Stefan Treue, A Pressure Injection System for Investigating the Neuropharmacology of Information Processing in Awake Behaving Macaque Monkey Cortex. Jove, 3/14/2016, Issue 109; doi: 10.3791/53724