Comprehensive evaluation of carboxylated nanodiamond as a topical drug delivery system.
The best strategy in the development of topical drug delivery systems may be to facilitate the permeation of drugs without any harmful effects, while staying on the skin surface and maintaining stability of the system. Nanodiamonds (NDs) play a key role with their excellent physicochemical properties, including high biocompatibility, physical adsorption, reactive oxygen species (ROS) scavenging capability, and photostabilizing activity. Z-average sizes of carboxylated ND (ND-COOH) agglutinate decreased significantly as the pH increased. Fluorescein-conjugated ND was observed only on the stratum corneum, and no sample diffused into the dermal layer even after 48 hours. Moreover, ND-COOH and ND-COOH/eugenol complex did not show significant toxic effects on murine macrophage cells. ND improved in vitro skin permeation >50% acting as a "drug reservoir" to maintain a high drug concentration in the donor chamber, which was supported by quartz crystal microbalance results. Moreover, ND-COOH could adsorb a drug amount equivalent to 80% of its own weight. A photostability study showed that ND-COOH increased the photostability ~47% with regard to rate constant of the eugenol itself. A significant decrease in ROS was observed in the ND-COOH and ND-COOH/eugenol complex compared with the negative control during intracellular ROS assay. Moreover, ROS and cupric reducing antioxidant capacity evaluation showed that ND-COOH had synergistic effects of antioxidation with eugenol. Therefore, ND-COOH could be used as an excellent topical drug delivery system with improved permeability, higher stability, and minimized safety issue.
College of Pharmacy, Dongguk University-Seoul, Gyeonggi, Republic of Korea.
Dae Gon
DG
Lim
College of Pharmacy, Dongguk University-Seoul, Gyeonggi, Republic of Korea.
Ki Hyun
KH
Kim
School of Chemical Engineering and Material Science, Chung-Ang University, Seoul, Republic of Korea.
Eunah
E
Kang
NanoResource Co. Ltd., Seoul, Republic of Korea.
Sun Hee
SH
Lim
NanoResource Co. Ltd., Seoul, Republic of Korea.
Jeremy
J
Ricci
NanoResource Co. Ltd., Seoul, Republic of Korea.
Si Kwon
SK
Sung
NanoResource Co. Ltd., Seoul, Republic of Korea.
Myoung Taek
MT
Kwon
College of Pharmacy, Dongguk University-Seoul, Gyeonggi, Republic of Korea.
Seong Hoon
SH
Jeong
D000327:Adsorption; D000818:Animals; D002460:Cell Line; D016503:Drug Delivery Systems / Q000379:methods*; D004355:Drug Stability; D005054:Eugenol / Q000493:pharmacokinetics / Q000494:pharmacology; D019793:Fluorescein / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D008264:Macrophages / Q000187:drug effects; D051379:Mice; D046529:Microscopy, Electron, Transmission; D058612:Nanodiamonds / Q000008:administration & dosage* / Q000737:chemistry*; D056951:Photoelectron Spectroscopy; D017382:Reactive Oxygen Species / Q000378:metabolism; D012869:Skin Absorption / Q000187:drug effects*; D017550:Spectroscopy, Fourier Transform Infrared; D034421:Sus scrofa; D014466:Ultraviolet Rays
D058612:Nanodiamonds; D017382:Reactive Oxygen Species; D005054:Eugenol; D019793:Fluorescein
anti-oxidation; drug delivery; nanodiamond; photostability; skin permeation