Capsules Tuned For Drug Delivery, Imaging

Self-assembled capsules held together by either hydrogen or metal bonds may find use in drug delivery and imaging, reported University of Missouri chemistry professor Jerry L. Atwood. Prepared from C-alkylpyrogallol[4]arene substrates, the capsules self-assemble in solution as 4-nm-diameter hexamers held together by hydrogen bonds. “To make a few grams is an hour’s work,” Atwood said, noting that his team can tune the capsules’ stability by varying the alkyl chains. If the substrate molecules are combined in solution with a metal, capsules form with metal atoms at the seams instead of hydrogens. Either type of capsule can gather together into spherical “rafts” about 20 capsules across. Atwood envisions creating therapeutic rafts combining hydrogen-bonded and mixed-metal capsules; the hydrogen-bonded capsules would contain a therapeutic agent, and the metal capsules would incorporate radioactive elements for imaging. The metal capsules would also be magnetic so that an external magnetic field could be used to direct the rafts to a specific location, where an oscillating magnetic field could rupture the hydrogen-bonded capsules to deliver the drug.

C&EN Covers The ACS National Meeting

Want the scoop on the ACS meeting in San Diego? Check out C&EN Picks, a series of videos that spotlight sessions selected by C&EN staff. Reporters also fan out across the meeting to bring you news coverage. Find it all collected at C&EN's meeting page, cenatacs.tumblr.com.