title: Particle size tailoring of ursolic acid nanosuspensions for improved anticancer activity by controlled antisolvent precipitation.
abstract: The present study was aimed at tailoring the particle size of ursolic acid (UA) nanosuspension for improved anticancer activity. UA nanosuspensions were prepared by antisolvent precipitation using a four-stream multi-inlet vortex mixer (MIVM) under defined conditions of varying solvent composition, drug feeding concentration or stream flow rate. The resulting products were characterized for particle size and polydispersity. Two of the UA nanosuspensions with mean particle sizes of 100 and 300 nm were further assessed for their in-vitro activity against MCF-7 breast cancer cells using fluorescence microscopy with 4',6-diamidino-2-phenylindole (DAPI) staining, as well as flow cytometry with propidium (PI) staining and with double staining by fluorescein isothiocyanate. It was revealed that the solvent composition, drug feeding concentration and stream flow rate were critical parameters for particle size control of the UA nanosuspensions generated with the MIVM. Specifically, decreasing the UA feeding concentration or increasing the stream flow rate or ethanol content resulted in a reduction of particle size. Excellent reproducibility for nanosuspension production was demonstrated for the 100 and 300 nm UA preparations with a deviation of not more than 5% in particle size from the mean value of three independent batches. Fluorescence microscopy and flow cytometry revealed that these two different sized UA nanosuspensions, particularly the 300 nm sample, exhibited a higher anti-proliferation activity against the MCF-7 cells and afforded a larger population of these cells in both early and late apoptotic phases. In conclusion, MIVM is a robust and pragmatic tool for tailoring the particle size of the UA nanosuspension. Particle size appears to be a critical determinant of the anticancer activity of the UA nanoparticles.
authors: State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Macao, China; School of Chemistry and Pharmaceutical Engineering, Qilu University of Technology, Jinan 250353, China.
authors: Yancai
authors: Y
authors: Wang
authors: State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Macao, China; Beijing Aohe Pharmaceutical Research Institute Co. Ltd., Beijing 101113, China.
authors: Ju
authors: J
authors: Song
authors: School of Pharmacy, The Chinese University of Hong Kong, Hong Kong.
authors: Shing Fung
authors: SF
authors: Chow
authors: School of Pharmacy, The Chinese University of Hong Kong, Hong Kong. Electronic address: albert-chow@cuhk.edu.hk.
authors: Albert H L
authors: AH
authors: Chow
authors: State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Macao, China. Electronic address: yzheng@umac.mo.
authors: Ying
authors: Y
authors: Zheng
mesh_terms: D000970:Antineoplastic Agents / Q000737:chemistry* / Q000494:pharmacology; D017209:Apoptosis / Q000187:drug effects; D002453:Cell Cycle / Q000187:drug effects; D011232:Chemical Precipitation; D004355:Drug Stability; D005260:Female; D006801:Humans; D061986:MCF-7 Cells; D046529:Microscopy, Electron, Transmission; D053758:Nanoparticles / Q000737:chemistry*; D010316:Particle Size; D015203:Reproducibility of Results; D012995:Solubility; D012997:Solvents / Q000737:chemistry; D013499:Surface Properties; D013535:Suspensions / Q000737:chemistry* / Q000494:pharmacology; D014315:Triterpenes / Q000737:chemistry* / Q000494:pharmacology*; D000097245:Ursolic Acid
chemical_list: D000970:Antineoplastic Agents; D012997:Solvents; D013535:Suspensions; D014315:Triterpenes; D000097245:Ursolic Acid
keywords: Antisolvent nanoprecipitation; Breast cancer; In-vitro anticancer activity; Multi-inlet vortex mixer (MIVM); Nanoparticles; Ursolic acid