Sticky dispensing system

Product design and development consultancy 42 Technology has developed a precision powder dispensing system that could accelerate drug development programmes.

This technology - called ‘sticky web’ - is capable of dispensing tiny amounts of powder, typically from 0.1 to 100mg, at high volume manufacturing speeds. It is based on 42T’s discovery that the quantity of powder adhering to a piece of sticky tape is directly proportional to the surface area of the tape.

The consultancy has subsequently developed the core technology, several adhesives and designs for a high-speed powder dispense drum and production machine capable of delivering up to 60,000 doses per hour with accuracies of better than 4 per cent.

Sticky web takes its name from adhesives being ‘printed’ onto an edible or inert web and the sticky surface then being coated with powder; the powdered areas can then be cut, folded, rolled or further processed.

The approach was developed initially by 42T and GlaxoSmithKline (GSK) to help remove a time-consuming, costly stage in the development and approval of new drugs, vaccines and other biologically-active materials, but the approach works with virtually any powder.

As most drugs are ultimately manufactured in high volumes as tablets or capsules, the industry relies almost exclusively on mixing small quantities of active substances with bulking agents to make them easier to weigh out and handle during subsequent processing.

The problem with this approach is that extensive formulation and stability studies are essential to eliminate any potential compatibility issues between the active materials and binders, which can take three months or more. By working with pure drugs, sticky web avoids or reduces the need for these studies.

The worldwide pharmaceutical rights for the new dispensing technology are being retained by GSK, with 42T gaining the rights for all other markets.

'The generic approach can be adapted to virtually any industry requiring accurate dosing of powders and the web can be a flat carrier tape, bubbles or tablets. Two or more substances can even be combined within the same delivery package, making the possibilities for applications such as flavourings, speciality chemicals and diagnostic testing kits virtually unlimited,' said Howard Biddle, managing director of 42T.

'GSK is pleased with the outcome of this project - a novel technique, for which patents have been applied, that has the potential to facilitate the development and manufacture of drug products,' added Dr Keith Smith, manager of strategic technologies at GSK pharmaceutical development.

Each circular powdered area shown in the image here contains 4.7mgs of an active drug substance