Expert develops nanoparticle drug delivery method to replace eye drops

This new method, developed by a team of researchers led by biomaterials and drug delivery expert Dr John Tsibouklis at the University of Portsmouth, uses biodegradable polymer nanoparticles to administer drugs to the eye.

Nanoparticles are microscopic particles measured in nanometres (nm). These particles are so small that an ant, for example, measures millions of nanometers across.

Dr Tsibouklis said biodegradable polymers can be combined with drugs in such a way that the drug is released into the eye in a very careful and controlled manner.

The drug would have to be placed into the eye just once.

'The drug's release can be timed so it is constant, cyclic or triggered by an environmental or chemical signal, and the drug delivering polymer can be broken down naturally by the body when it is no longer needed,' Dr Tsibouklis said.

People with eye conditions who use eye drops regularly would benefit from the biodegradable polymer drug delivery method.

Eye drops have many disadvantages – two main ones being the need to administer drops regularly and low ocular bioavailability (too little of the drug is getting to areas of the eye most in need).

The common alternative option to eye drops, ophthalmic inserts, achieve sustained drug delivery but suffer from limitations also – they are difficult to insert, easy to misapply, and are expensive to manufacture.

Dr Tsibouklis is a reader in polymer science at the University of Portsmouth’s School of Pharmacy and Biomedical Sciences.

Dr Tsibouklis, and colleagues Dr Eugen Barbu, Dr Tom Nevell and Dr Liliana Verestiuc describe the new drug delivery systems in a paper, titled ‘Polymeric materials for ophthalmic drug delivery: trends and perspectives', published in the Journal of Materials Chemistry.

He said that the new drug delivery systems hold significant promise for the pharmaceutical industry.