For demanding applications that require a full-featured microinjection system, Tritech Research offers the MINJ-D All-Digital Multi-Pressure microINJECTOR™. In basic microinjection, a hollow needle with a microscopic tip is filled with a liquid, poked into a target, and then temporarily pressurized so as to inject some of the liquid into the target. The variables that determine the amount injected are pressure, time, viscosity of the liquid, and diameter of the needle opening. A simple, practical system for accomplishing this is our MINJ-1 microINJECTOR™ (standard model). While the MINJ-1, and its line of accessories, help many scientists breeze through their microinjections, some experiments and procedures require a higher level of sophistication, accuracy, and reproducibility. In basic microinjection, the needle is either at a user-set pressure when injecting, or at atmospheric pressure when not injecting. In some cases, backflow of cytoplasm or medium into the needle can be problematic. For these cases, a lower "holding pressure" that is lower than the injecting pressure, but higher than atmospheric pressure is useful between injections. A holding pressure can also reduce needle clogging. No matter how careful a person is, needles occasionally do clog. For these cases, a short blast of a "clearing pressure," higher than the normal injection pressure, is useful to unclog the needles. The MINJ-D employs a user-friendly microprocessor to digitally synthesize injecting, holding and clearing pressures, as well as injection durations reproducibly. Using a simple "Menu" button, and Up and Down buttons, anyone can set the pressures and the injection duration in seconds. It's so intuitive, you won't have to read the directions! Here are the key features and specifications of the Digital microINJECTOR™:

• Most compact on the market
  6" x 7" x 3" and weighs under 2 lbs.
  (15cm x 17cm x 7cm and weighs under 1 kg)
• Fast response time between pressures (~100 milliseconds)
• Simple 3-button control
• Digital display with backlight for easy reading
• Microprocessor accuracy
• Foot pedal included for hands-free injection control
• Pressure range (applies to each of holding, injecting and clearing pressures): 0 - 100 psi
• Programmable Injection Duration: 0.1 - 999.0 seconds
• Built-in Vacuum Generator can be used to front-fill needles by aspiration
• Manual Injection Mode
• Injection Data-logging Port for optional computer interface
• Injection Control Port for optional computer control

The MINJ-D can be attached directly to a laboratory compressed air jet or attached to a compressed Nitrogen cylinder using a pressure regulator such as our TREG-N2.  The system is designed to use a minimum of gas, so even a small cylinder may last for months or years. When ordering, please let us know if you intend to attach your injector to a compressed gas source or an in-house air jet, so that we can provide you with the proper fittings for attachment.

The output of the microINJECTOR needs to be coupled to something. For example, if you're using glass microcapillary needles, our MINJ-4 microINJECTOR™ Brass Straight-Arm Needle Holder will do the job cost-effectively.