Motion control’s critical role in medical R&D

When the design team at Advanced ChemTech realized that versatility, ease of use, and cost effectiveness were only the beginning of what their customers wanted in a peptide synthesizer, they decided to broaden their scope. Users were looking for the freedom to dictate the chemistry they needed so that they could save time and costs in processing and purchasing bulk chemicals and consumables.

Advanced ChemTech provides fine chemicals to research and pharmaceutical markets and manufactures raw materials to produce peptides. It also provides state-of-the-art peptide synthesizers, and acts as a service organization for custom peptide synthesis.

Taking the needs of its customers into consideration, Advanced ChemTech engineers designed the Tetras Peptide Synthesizer – presently the only asynchronous multiple peptide synthesizer on the market that can perform independent peptide synthesis with variable scales, activations, lengths, and sequences on one machine. A modular design facilitates near-zero downtime and allows user-defined protocols for each reaction vessel. Variable synthesis scales can be run in parallel, and disposable, isolated reaction vessels eliminate cross-contamination.

The Tetras can perform various chemistries on separate peptides simultaneously depending on the size of the reactors:

The Tetras allows the user to add or remove peptides at any time and is easily adapted to any variation in chemistry.

Incorporating 32 separate injection stations with digitally controlled metering pumps, the system precisely delivers reagents and solvents. Independent injection stations dispense accurate volumes yielding the highest-quality peptides that can be synthesized with today’s technology. The system comes with 8 external and 24 internal stations, but is fully customizable to any requirements. Internal stations use 250ml bottles, while the external station has no volume limit. Peptide creation is essential for the research and development (R&D) conducted at universities and pharmaceutical companies, with many geared toward cancer research.

Motion matters

The Tetras integrates 41 AllMotion controllers for a variety of functions. The company’s EZHR23ENHC controller drives a large stepper motor that turns the gearbox that spins the carousel to keep the reaction vessels moving from station to station as well as to continue mixing the liquids. The 2.25" x 2.25" EZHR23ENHC is an intelligent stepper motor controller plus driver designed to bolt directly to the back of the stepper motor it controls.

The controller can operate without executing a preset program upon power up or be controlled via communications with a computer. Each EZHR23ENHC uses a single, 4-wire bus, containing two power wires and two communications wires. Commands can be issued from any serial terminal program. The Tetras incorporates the AllMotion USB-485 communications converter for all interactions with the controllers.

To operate 36 small stepper motors that run the piston pumps used to deliver amino acids to the mixtures, the Tetras has 36 EZHR17EN high-resolution stepper motor controllers plus drivers. These controllers dispense liquids at a rate of 25ml per minute with an accuracy of 50µl per pump. The EZHR17EN controllers measure 1.6in2 and are fully intelligent devices. Up to 16 controllers can be daisy-chained together.

The Tetras uses four EZSV23 servo controllers to dispense the common solvents used throughout the machine. The EZSV23 is designed for rapid implementation of brushed or brushless DC motors into an application. Similar to the other controllers used in the Tetras, the 2.25in2 EZSV23s are fully intelligent. The devices require little to no tuning when used with most 3" diameter or smaller motors. Each can handle up to 16 daisy-chained motors.

The Tetras has four purge stations that deliver inert gas to empty the reaction wells of fluids. An extremely fast wash cycle option increases machine speed by about 45% with a minimum number of 40 peptides running simultaneously.

The software-controlled system supports easy customization of user-defined protocols. Each peptide can use separate protocols during the same synthesis, peptides can be added or removed at any time, and users can get email notifications on syntheses states. The flexibility of the Tetras enables users to synthesize widely variant peptides, simultaneously, without delay waiting for previously begun peptides to be completed. By reversing the idea that a fluid should be delivered to reaction vessels, the Tetras takes the reactions themselves to the individually and separate fluid supplies. In combination with sinusoidal oscillation, this ensures an uncontaminated mix cycle that is more effective than the nitrogen bubble delivery method used in synthesizers of the past.

AllMotion
www.allmotion.com

Advanced ChemTech, A Creosalus Co.
www.advancedchemtech.com