in-PharmaTechnologist presents a roundup of recent drug delivery research, including a pH activated capsule and plant-based administration.
Researchers have created drug delivery capsules that deliver therapeutic loads when exposed to pH and redox conditions found within cells. When in the pH and redox conditions found in the blood the capsule shrinks and remains stable, write researchers in the journal Advanced Materials .
Then, when it moves into a cell, where conditions are acidic and reducing, the capsule swells and begins to be degraded. Acidic conditions cause the capsule to swell allowing reducing elements, such as glutathione, to break it down and release the drug.
Using a combination of factors to break down the capsule overcomes a problem associated with redox-responsive particles, the researchers claim. Redox-potential varies from cell-to-cell and as such capsules that rely solely on reduction to break them down can lose efficacy in some environments.
A review paper has called for researchers to drive development of orally-delivered plant-produced therapeutics by investigating the mucosal immune system. Advances have made production of drugs in green plants a reality but research into their use as delivery vehicles has lagged behind.
“The provision of orally produced and delivered low-cost therapeutics and vaccines is where plant-made therapeutics reach their zenith as a technology, yet remains the least advanced ﬁeld of development”, researchers write in the journal Biotechnology Advances .
Encapsulating a drug in plant cells could protect the treatment as it passes through the body. However, for plant-based delivery to be viable researchers must be able to avoid undesirable immune responses seen in some studies by understanding the mucosal immune system.
A growth factor has been delivered into and across the skin using iontophoresis, researchers write in Molecular Pharmaceutics . Development of the system could provide a non-invasive protein delivery platform.
Having run the experiment using pig and human skin the researchers now plan to test the process in vivo in an animal model. As research progresses the team will optimise the current density and duration to ensure an effective dose is delivered while reducing the risk of skin irritation.
Researchers at Massachusetts Institute of Technology have developed a method for producing micro-particles with compartments to carry drugs. The research, published in the Journal of the American Chemical Society , could improve controlled release of drugs.
“These responsive micromolds could be a versatile tool in several fields, including tissue engineering, drug delivery, diagnostics, drug discovery, and 3D cell culture systems”, the researchers write.