Scientists at the University of Bradford say they are on the brink of bringing to market a new method of pain relief which would simultaneously ease the care path of patients and save the NHS thousands of pounds.

The breakthrough would see ‘smart gels’ injected into the body at the site of pain, releasing drugs over a specified time. The findings are published this week in the Journal of Colloid and Interface Science.

So-called ‘smart gels’ have been around for a while but now academics are on the brink of using them to administer drugs by injecting them directly into the body at the site of the pain.

Smart gels are essentially a matrix of polymers (some are already used in everyday items like creams and gels) and fluids but it’s the way they react to various stimuli, such as heat and pressure which makes them so useful.

It is this characteristic which means they can be used to administer drugs over a period of time, whether that’s hours or weeks. Once the payload of drugs is delivered, the smart gel polymers are harmlessly metabolised by the body.

Bana Shriky, post-doctoral research assistant in the Faculty of Engineering & Informatics at the University of Bradford, said: “The material is widely used in soaps, creams and gels – things we all have in our bathroom cupboards. It has a similar structure to soap and cleaning detergents. The gels can be tailored to deliver a fully controlled release of lifesaving medications.”

In their latest study, University of Bradford scientists, led by Professor Tim Gough, investigated the properties of smart hydrogel formulations for future use as injectable controlled drug carriers. The gels were prepared from a safe, biodegradable and cheap polymer, using a simple two-step process. 

Academic Bana Shirky with SMart gels Polymer IRC

Bana said: “The systems can be injected as drug-loaded solutions directly to the area of interest, during hip, knee or shoulder surgeries. This allows access to locations difficult to reach with conventional delivery systems.  

“After injection, these watery solutions instantly transform into a soft ‘gel depot’, releasing a drug over a specified time ranging from hours to weeks. Once the dose is delivered, the hydrogel is metabolised safely by body tissues.”

A kilo of the smart hydrogel currently costs around £100 but patients would typically require just 10 grams. Added to that would be the cost of the drug but Bana says further monetary savings would also likely be made because patients would require fewer hospital visits.

She added: “Smart hydrogels promise to reduce the number of drug doses and reflect positively on the patient’s experience, saving a lot of unnecessary costs.”

Scientists say the ‘one-shot gel injection’ can be easily engineered to deliver different drugs over a pre-specified time, so matching an individual patient’s needs. They expect it to benefit postoperative cases and patients with chronic illness.  

Human trials are planned for later this year. 

The collaborative work used state-of-the-art characterisation methods to study the internal structure of  the gel network at the University of Bradford and the Science and Technology Facilities Council’s Rutherford Appleton laboratories.

The team’s findings are discussed in detail in the Journal of Colloid and Interface Science, Volume 565, published April 1, 2020, Pages 119-130; also available online:

https://www.sciencedirect.com/science/article/pii/S0021979719315632#s0120