Researchers from Bangalore's Indian Institute of Science have developed a novel microcapsule drug delivery mechanism for insulin using micro-shock waves that reduces the need for those oft-dreaded needles.
The shock waves are produced externally using a hand-held shock generator placed near the location of the microcapsule. The device does not need to touch the body to trigger the release of the drug.
"We understood the discomfort faced by diabetic patients who take regular insulin injections and wanted to develop a technology to reduce their distress," Dipshikha Chakravortty, a professor at the Indian Institute of Science, told Chemistry World. Initial placement of the microparticles in the subcutaneous layer of the skin still requires an injection, she acknowledged, but said the overall number of injections would still be reduced.
The team developed a microcapsule made of spermidine and dextran sulfate. The formulation released the insulin contained within the microparticles in experimental mice when exposed to the shock waves, which cause an increase in pressure, explains Chemistry World.
According to a publicly available paper published in a journal run by the Royal Society of Chemistry, alternating layers of positively charged spermidine and negatively charged dextran sulfate were coated onto a negatively charged template of calcium carbonate. The microcapsules were developed at a pH of 5.6.
The release profile of the medication upon initiation of the shock waves can be sped up or slowed down by changing the pH. After exposure to 5 waves, almost all of the drug was released.
In addition, 400 microliters (thousandths of a milliliter) of drug was used in each 200-microliter hollow capsule, the paper says.
Another model of the delivery system successfully released the topically applied antibiotic ciprofloxacin to fight the Staphylococcus aureus bacteria and promote wound healing. The scientists say the shock waves combat biofilm, a protective coating that makes infections more resistant to antibiotics.
According to Chemistry World, Chakravortty and her colleagues are now trying to eliminate the use of explosives in their hand-held shock-wave generation device.