Reagent deposition system meets medical needs

Edited by the Engineeringtalk editorial team Jul 30, 2008

The Nanodrop system supplied by Innovadyne uses motorised syringes to aspirate and a pressurised solenoid valve arrangement to dispense.

Innovadyne Technologies and Horizon Instruments have collaborated to produce a reagent deposition system tailored to the exact requirements of a medical diagnostics manufacturer.

The customer had selected Innovadyne as a provider of a noncontact deposition technique for providing highly precise and repeatable droplets in the nanolitre to microlitre range.

The Nanodrop system supplied by Innovadyne uses motorised syringes to aspirate and a pressurised solenoid valve arrangement to dispense.

The constant presence of clean system fluid in the syringes and solenoid valve assembly preserves the accuracy and repeatability of deposition throughout the lifetime of the instrument.

The fact that the liquid being deposited never touches these critical components reduces maintenance and maintains precision.

Particulate suspensions, bead and cell-based mixtures and reactive solutions can all be dispensed.

The customer needed to deposit a fine slurry of 1um diameter ferromagnetic particles.

While the benchtop Nanodrop system suited efficacy testing andan initial test-kit development, Innovadyne did not offer a system with the whole range of functionality needed by the client for clinical trial batches or initial production.

The customer's pilot-scale production line was based on trays of product being processed.

Horizon Instruments integrated the eight-tip Nanodrop dispensing harness into an X-Y-Z motion platform that allowed multiple depositions onto each of the 44 devices on a tray.

The interface was via a PC with windows-based custom software written by Horizon.

This controls the X, Y and Z axes, the wash station and all aspects of the Nanodrop system.

Innovadyne's willingness to co-operate fully on the project enabled Horizon to access sub-functions within the Nanobuilder software and provide new solutions tailored to this customer's needs.

Horizon developed a series of tokenised instructions that bundled individual Nanobuilder commands into a useful instruction set.

For example, the "Move tips over wash station" instruction contained over twenty individual Nanobuilder axis and pump move commands.

This simplified control system allows the user complete freedom to quickly define repeatable arrays of dispensed micro dots in almost limitless combinations of number, volume and position.

Incorporation of the Nanobuilder structure into the host software enables a seamless transition from benchtop development to pilot batches and full-scale production.

Smart-valve technology on the Nanodrop allows different amounts of fluids to be deposited from each of the eight channels as a standard function.

Horizon was also able to offer this customer the ability to vary the aspirate volumes on individual channels.

This enhancement was particularly useful since very costly reagents were being used in some channels.

The aspirate and dispense cycles can now be tailored to suit the individual dispensed volumes and the size of the harness, reducing any wastage of reagents to an absolute minimum.