XWI Motorized Microinjector

For microinjection workflows, manual operation of the injector using the rotary encoder on the controller gives users direct control over injection and aspiration. The injection rate in manual operation mode spans three orders of magnitude, with fluid displacement rates varying from 3.1 µL/revolution to 70 nL/revolution in five discrete steps. Separation of the injector mechanical from its controller allows users to control the injector without introducing vibrations into their preparations.

Manual operation of the XWI is suited for numerous applications including:

• Pronuclear Injection
• Generation of holding force
• Nuclear transfer
• Preimplantation genetic testing
• Embryonic stem cell injection
• Xenopus oocyte injection
• Embryo injections
• Polar body biopsy
• Blastocyst injection
• Single-cell picking

For stereotaxic and other tissue injections, the XWI has a programmable automatic mode with injection and aspiration rates between 1 nL/s and 10 µL/s. Unlike other nanoliter injectors, the XWI can be easily configured for use with injection pipettes fabricated from glass capillaries with outer diameters between 1.0 and 1.2 mm, regardless of inner diameter. The micropipette holder of the XWI can be mounted to all commercially available stereotaxic frames with standard adaptors. For other tissue injections, the micropipette holder can easily be held in one hand while the controller is operated either by the other hand, or the included footswitch. Alternatively, the micropipette holder fits the standard rod holders of most micromanipulators and can be mounted on any Sutter Instrument micromanipulator. Use of a glass pipette as a microinjection needle, instead of a metal syringe, minimizes damage to the target tissue. At the same time, it can improve targeting and specificity by allowing for the use of needles with small outer diameters and bore diameters as small as 4 µm. In automatic mode, the XWI can be programmed to inject between 1 nL and 500 µL of solution in a single programmed injection.

Automatic operation of the XWI microinjector is suited for any application where a pneumatic, hydraulic, or syringe pump injector might be used including:

• Stereotaxic injection
• Nerve injection
• (Xeno)transplantation
• Subretinal injection
• Intravitreal injection
• Intrathecal and spinal cord injection
• Round window and semicircular canal injection
• Cerebrospinal fluid (CSF) sampling
• Controlled dispensing of fluid

The XWI motorized microinjector can also be controlled by a computer via USB with user-designed software, using freely available Sutter Instrument drivers and software development kits.

The XWI XenoWorks® Motorized Microinjector Includes:

• Hydraulic injector body
• ROE controller
• footswitch
• microtool holder
• injection and filling tubing
• connecting cables
• manual