Medical SECTA

A new medical pump has been developed by UK researchers that can deliver both large and microscopic volumes of fluid with no loss of accuracy.

Developed by PDDi, (PDD innovations, part of the PDD group) SECTA is a low cost, accurate, disposable pump which will, the developers claim, offers far greater accuracy and flexibility in a number of applications, from medical infusion to pain management.

The new pump mechanism is designed to overcome the common deficiencies of peristaltic, syringe and diaphragm pumps as it is not sensitive to pressure and temperature effects.

Peter Ross, one of the designers of SECTA, explained that all the parts critical for accuracy are found within the pump, allowing the driving mechanism to be simplified. ‘What we are doing is taking a different starting point by making a rotary pump made of polyethylene, which is light and a low cost material.’

‘The basic idea is that all the precision is held in the plastic moulding which costs very little and you can throw it away after use. And then all you need is a very simple motor drive to be able to operate it.’

‘And in many applications,’ he added, ‘particularly when you have to prevent fluid flow when a pump isn’t operating, simpler devices tend to require anti-freeflow devices to prevent flow. This is built into the pump itself - if it is not rotating it actually blocks the flow.’

The technology, which is derived from two precision plastic moulded parts with tight tolerance, allows the user far greater control over rate and volume of fluid dispersal. By using a rotary motion, continuous flow can be achieved, leading to uses where constancy of flow at low rates is important.

Ross foresees a pump capable of delivering between 1 and 5 microlitres. At present it is at 5 microlitres with a flow rate between 100 microlitres per hour to 1.5 litres.