A new study published in the January issue of ACS Nano offers insight into cutting edge world of drug delivery research. In the study, UCLA and Northwestern University researchers used nanoscale polymer film coatings to circumvent typical bodily defenses while delivering a drug payload.
An inert nanoscale polymer film (‘orders of magnitude thinner’ than conventional drug deliver coatings, say researchers) was used to coat sandwich-like chips which held the anti-inflammatory drug Dexamethasone.
The film was designed to ‘hide’ the chips from the body’s natural defenses.
In experiments with lab mice, coated chips suppressed the expression of cytokines, proteins released by the body during an immune system response. Uncoated implants generated an inflammatory response in the tissue surrounding the implant.
The nanomaterial coating shielded the implant from bodily defenses so effectively that tissue in the mice with no implants was virtually identical to that of mice with coated implants.
Such technology might be particularly applicable to surgically implanted devices like cardiac stents or pacemakers to avoid inflammation and redundant surgeries. Said Dean Ho, the study’s senior author,
“As implantable devices continue to find widespread application in cardiovascular medicine, neural disorders and diabetes, the nano-cloaking capabilities can serve as a widely applicable approach to enhance the lifetime of these devices. The nanomaterial technology serves as a non-invasive and biocompatible platform for the delivery of a broad range of therapeutics.”
Because of their size, nanowires and other nanomaterials hold promise in future drug delivery systems. Nanomaterials can penetrate tumors more easily and could be coated with antibodies or other materials that selectively target cells while avoiding others.
An article published in a September issue of ACS Nano reported the development of a protein coating that could turn nanowires into a drug delivery system. Gregory Bohach, David McIlroy, and Carolyn Hovde used of the coating to enable silica nanowires to enter cultured human cells and deliver a lethal dose of toxin.
The researchers report nanowires coated with the protein fibronectin penetrate cells more easily than uncoated nanowires. In experiments with human and animal cells, they showed that coated nanowires can enter and deliver a toxic agent called StxA1 that killed the cells.