Contactless dispensing is used to add different substances such as adhesives, inks, without physical contact between the dispensing system and the substrate. Thereby pico- or nanoliter can be added at a very high pace to the substrate without damaging substrate structures or contaminating equipment.

Microdispensing refers to the dispensing of small volumes between a few picoliter to a few microliters.

With drop on demand printing, small drops are generated by means of an on and off process. An example is the microdrop Autopipette, which uses a piezo actuator to start dispensing single droplets. The process is only active when a current is supplied to the piezo actuator and stops when the current is removed.

Jet dispensing or continuous jet dispensing (CJI) refers to the continuous dispensing of larger jets of fluids. An example of where this technology is used is in the microjet systems from microdrop.

Microdispensing allows the dosing of different liquids: This includes

• Solvents with low vapor pressure
• Hydrogels
• Organic compounds
• Solid materials that can be melted at high temperature
• Adhesives
• Water-like solutions

Read more in our white paper

If there’s limited information about whether your desired liquid is suitable for microdispensing, we offer dispensing tests and loaner dispensing systems to help you evaluate its compatibility.

Through these tests, we assess whether the material can be reliably dispensed and determine the optimal parameters for doing so. This ensures that your application is supported with the right setup from the start.

Contact us for more information and discuss the best way forward.

Microdispensing is a very popular technique used in material sciences, industry applications and life sciences. Examples for the life sciences include:

• Tissue Engineering & Cell Dispensing: Read more
• Cryo-EM Sample Preparation: Explore here
• 3D-Printed Drugs for Research: Discover the case
• Polymer-Based Optical Sensors: Check it out

Ink-jet based dispensing offers several adavantages over other techniques:

• Versatility: The technology can reproducibly dispense a wide range of liquids, making it highly adaptable across applications.

• Precision and Scalability: It enables highly reproducible dispensing from volumes as small as 30 picoliters, allowing for miniaturization and high-throughput reaction setups.

• Digital Control: The dispensing process is digitally controlled. Larger volumes can be built up by adding smaller droplets, with full control achieved by applying and switching off current to the piezo actuator.

• Non-Contact Process: Because the liquid is ejected without touching the substrate, compounds can be combined directly at the target location, reducing the risk of cross-contamination.

• Speed and Parallelization: Droplets are dispensed rapidly, enabling parallel processing and faster workflows.

• Patterning Capability: The high precision of droplet placement allows for the creation of delicate and complex patterns.

We aim to provide the most appropriate solution for your specific requirements. That’s why we offer a range of flexible options:

• The MD-E-series driver electronics are available in different configurations and can control up to four separate dispenser heads.

• The Autodrop Gantry/AD-P series is an automated XYZ-positioning system that stands out for its modular design, allowing it to adapt precisely to your application needs. With available add-ons, a basic dispensing setup can be expanded to support up to four dispenser heads or eight pipettes, offering scalable and customizable automation.

To find the optimal product that fits your needs the best, we need some information regarding the following:

• What kind of liquid would you like to dispense? Viscosity, concentration, description of the liquid etc.
• What kind of solvent are you using?
• If there are particle in the liquid: How big are they and how is their concentration?
• Diameter of one droplet and the droplet emission frequency.
• Dispensing volume: single droplet and throughput of droplets/second
• How many dispenser heads do you need at the same time?
• Are you interested in the option to upgrade the system to more dispenser heads later?
• Do you need a xyz-positioning system?
• Description of your application.
• What is the address of the company and if you’re an EU based company what is your VAT?

This test  - will check the following:

• Basically, the dispensing possibility of the fluid.
• Selection of the best dispenser head for the fluid.
• Statement of the dispensing stability.
• Max./ min. dosing frequency.
• Droplet velocity. - in case of MD-K or AD-K systems
• Min./ Max. possible inner nozzle diameter.
• Driving parameters of the dispensing equipment.
• Allowed idle time.
• Possible dispensing characteristics which has to be considered.

Please send us the datasheet of the fluid and an amount of approx. 5-10ml.

Fill the storage bin with (water or the corresponding solvent) rinsing liquid and move the water to the nozzle by pressing the piston of the syringe. A jet will come out of the nozzle. Then suck the liquid in the tube to storage bin. The tube is empty when you see air bubbles in the glass. This is the real important rinsing step, because backwards you will get a higher flow speed. Clean also the nozzle and the area round the nozzle with a precision wiper during you press a jet out of the nozzle. This will prevent the collecting of fibres in the nozzle. Change the rinsing liquid 4 times and repeat the procedure. At least rinse with acetone, and dry with filtered air or N2 etc. the system for 3 minutes. (Air pressure about 2,5 bar). That should remove the last bits of water from the acetone evaporation.

Please try carefully the following: Dip the nozzle tip of the dispenser head (only the first 3mm, not the metal housing) into an ultrasonic bath.

Simultaneous, set the piezo on 2kHz and put the syringe onto the air filter and press.

• Before the experiment:
• • Ensure that the dispenser head has been cleaned throughly, if it has been used before.
  • Prepare a clean container (for the use) either as a reservoir for aspiration (AD-K-) or as a reservoir container (MD-K). Clean with compressed air, which is filtered and oil free, and solvent if necessary.
  • Prepare the liquid that you want to dispense:
    • Filter the liquid (pressure-assisted if required)
    • Fill the ink into the reservoir
    • Degas the liquid if needed
• Fill the dispenser and check the dispensing in front of the camera. If needed adjust the droplet for optimal performance.
• After use, clean the dispenser throughly. Follow proper cleaning protocols to ensure longevity and accuracy.

Watch also this video that shows the steps for a Micro Dispenser Head: How to assemble, fill, adjust and clean Microdrop Dispenser Head