Hydrogels for the treatment of Brain Tumours

Dr Vladimir Gubbala, Medway School of Pharmacy

The delivery of therapeutic agents to treat glioma, a type of brain tumour, is very challenging. Implantable hydrogels prepared from natural material, approved by the FDA, offer a novel and interesting option for the treatment of glioma in the brain. For those not working in the field of hydrogels, the jelly we enjoy with ice cream is a crude example of one (i.e. a powder substrate that is combined with water to produce a stable gel).

At the moment a brain tumour is problematic for more than just the obvious reasons. According to Dr Vladimir Gubala a lecturer in Chemistry and Drug Delivery at the Medway School of Pharmacy:

“Survival rates are very low because the glioma cells have one very unique property – they migrate within the brain, making it very difficult to catch them and treat them.”

Many of the traditional chemotherapies fail because they cannot overcome the blood-brain barrier, a tight layer of cells that protects our vital organ from pathogens and

from many other substances that could otherwise cause harm to our “central computer”. This barrier however, makes it equally difficult to pass lifesaving drugs into the brain. Radiotherapy options are limited by the dose and intensity, leaving the surgeon’s scalpel as the best option.

The largest portion of the tumour can be removed by observation but many cancer cells remain and migrate to other sections of the brain. The application currently explored at the Medway School of Pharmacy in collaboration with Dr Helene Castel from the University of Rouen, France is based on the development of a hydrogel that could be inserted into the cavity created during surgery that would then attract the unremoved cancerous cells and draw them out of the surrounding tissue and retain them within the hydrogel.

The prerequisite for a successful hydrogel as a new medicine is that it has to be simple and responsive. This means that the surgeon must be able to fill the cavity with a liquid, usually in volumes between 1 – 4 mL, which then turns into gel after a few minutes inside the cavity. The hydrogels are produced by shaking specific reagents that are initially in liquid form. Once the hydrogel is formed, some of its critical properties for example ‘softness’, stability, swelling or the ability to contain drugs that kill the trapped cancer cells have to be systematically studied under model physiological conditions at temperatures ranging from 21 – 37 degrees Celsius. This study must be done in an extremely robust and reproducible way to ensure accuracy of results – the perfect application for a Ther-Mix.

Dr Gubala said, “The Ther-Mix allows us to mix the reagents in various ratios, thus creating hydrogels with different properties. We can study up to 24 hydrogels at the same time, whilst ensuring that other variables such as shaking speed and temperature are very precisely controlled by the Ther-Mix. Such great precision is absolutely critical for us but I’m sure it is extremely important for many other material scientists preparing new, exciting materials. When I think now how we used to deal with this in the past, using some unreliable, make-shift, heated water baths with mechanical stirrers or the bulky and expensive shaking incubators, I am very glad I purchased a Ther-Mix as soon as it became available on the market.”

Watch this video to find out more about the Vitl Ther-Mix.