[1] Univ North Carolina Chapel Hill, UNC Eshelman Sch Pharm, Div Pharmacoengn & Mol Pharmaceut, Chapel Hill, NC 27599 USA
[2] Lomonosov Moscow State Univ, Fac Chem, Deparment Chem Enzymol, Moscow, Russia
[3] Univ North Carolina Chapel Hill, Ctr Nanotechnol Drug Delivery, Carolina Inst Nanomed, Chapel Hill, NC USA