Cartilage and intervertebral discs hardly contain any blood vessels to deliver drugs and are very compact tissues. Also RNA-based drugs cannot reach the cells inside the cartilage and intervertebral disc on their own. Moreover, they are degraded in the body very rapidly after administration and get removed right away. To avoid this, we need delivery systems that act like transportation systems. Like a truck transports goods, drug delivery systems carry drugs from the starting administration point to their destination within the body. Thus, they are used to act as shelters for the drugs to carry them safely to the cell. We aim to find delivery systems for drugs to target the cartilage.

In our research, we are working on various delivery systems such as albumin and nanoparticles. Albumin is a protein that functions as a natural transportation system within the body. Therefore, it is compatible with the body and does not trigger side effects, like inflammation. Nanoparticles are very small structures that are smaller than a thousandth of a millimeter in size and can be used as delivery systems. Their small size allows helps to get them through the dense cartilage and disc tissue and reach the cells. To further facilitate them to reach the cartilage and disc cells, we modify these mentioned delivery systems. For that, we add specific molecules to the delivery systems that act as a GPS to direct the system to the tissue. This way, we can specifically treat the joint and disc tissue and not cause side effects to other parts of the body.

To further support delivery to the tissues and their cells, we are looking at physics-based approaches to make the tissue more accessible. We use ultrasound for this, sound waves with high frequencies that we cannot hear. Ultrasound will be used to ‘open up’ the cartilage and disc tissue to the nanoparticle delivery systems, and to make their entry into the cells more easy.