Application of Nanotechnology in COVID-19 Vaccine
Lipid Nanoparticles
To talk more about lipid nanoparticles, they are composed of lipids which induce fats, fatty acids, waxes, glycerides, and fat-soluble vitamins. A lipid nanoparticle is composed of phospholipid bilayers with proteins. The phospholipids bilayer has two parts: hydrophobic (hate water) tails of fatty acid attached to one hydrophilic (love water) head made of a phosphate group. In an aqueous solution, phospholipids will self-assemble of different sizes and shapes. These phospholipid bilayers protect the cells from their environment and are selectively permeable.
The images above, on the left, demonstrate how the cell membrane comprises a hydrophilic head and hydrophobic tails. The image on the right shows the 3D structure of lipid nanoparticles with the white part, the hydrophilic head, and the yellow part, the hydrophobic tails. It will be easier to think of the liposome as the bent version of the cell membrane.
The drug delivery of lipid nanoparticles is proceeding towards a distinctive approach compared to traditional drugs. Scientists load drugs and an mRNA strand inside the lipid nanoparticles, which are then released to the target site and produce specific proteins, in the context of the COVID-19 vaccine, mRNA codes the spike protein of the virus. These nanoparticles behave as drug carriers to reach the desired destination safely. During the journey, they face challenges when passing the stomach’s acidic environment and overcoming the lung barriers. Fortunately, nanoparticles have the strength to withstand these environments without getting damaged.
As the nanoparticles reach the bloodstream, they look for the particular disease inside the circulatory system. For example, in tumour treatment, tumour tissue tends to have leaky blood vessels and their unique receptors of tumour cells. With this information, we can code the nanoparticles to look for these factors to detect them. Once the site is targeted, they can release the encapsulated drugs and disperse in a large surface area. Essentially, the tumour cells will be eliminated. This nanoparticle drug delivery is an advanced way to detect the disease without triggering health issues.
