Synergistic Antibacterial Effects of Nanoparticles Encapsulated with Scutellaria baicalensis and Pure Chlorhexidine on Oral Bacterial Biofilms.
Scutellariabaicalensis(SB) is a traditional Chinese medicine for treating infectious and inflammatory diseases. Our recent study shows potent antibacterial effects of nanoparticle-encapsulated chlorhexidine (Nano-CHX). Herein, we explored the synergistic effects of the nanoparticle-encapsulated SB (Nano-SB) and Nano-CHX on oral bacterial biofilms. Loading efficiency of Nano-SB was determined by thermogravimetric analysis, and its releasing profile was assessed by high-performance liquid chromatographyusing baicalin (a flavonoid compound of SB) as the marker. The mucosal diffusion assay on Nano-SB was undertaken in a porcine model. The antibacterial effects of the mixed nanoparticles (Nano-MIX) of Nano-SB and Nano-CHX at 9:1 (w/w) ratio were analyzed in both planktonic and biofilm modes of representative oral bacteria. The Nano-MIX was effective on the mono-species biofilms ofStreptococcus(S.)mutans,S. sobrinus,Fusobacterium(F.)nucleatum, andAggregatibacter(A.)actinomycetemcomitans(MIC 50 μg/mL) at 24 h, and exhibited an enhanced effect against the multi-species biofilms such asS. mutans,F. nucleatum,A. actinomycetemcomitans, andPorphyromonas(P.)gingivalis(MIC 12.5 μg/mL) at 24 h that was supported by the findings of both scanning electron microscopy (SEM) and confocal scanning laser microscopy (CLSM). This study shows enhanced synergistic antibacterial effects of the Nano-MIX on common oral bacterial biofilms, which could be potentially developed as a novel antimicrobial agent for clinical oral/periodontal care.
Department of Chemistry, Institute of Creativity, and Partner State Key Laboratory of Environmental and Biological Analysis, The Hong Kong Baptist University, Kowloon, Hong Kong, China. cfleung@hkbu.edu.hk.
Ken Cham-Fai
KC
Leung
Faculty of Dentistry, National University of Singapore, 11 Lower Kent Ridge Road, Singapore City 119083, Singapore. chaminda_jayampath@nuhs.edu.sg.
Chaminda Jayampath
CJ
Seneviratne
Faculty of Dentistry, The University of Hong Kong, 34 Hospital Road, Hong Kong, China. lixuanlwj@hotmail.com.
Xuan
X
Li
Institute of Chinese Medicine and Partner State Key Laboratory of Phytochemistry and Plant Resources in West China, The Chinese University of Hong Kong, New Territories, Hong Kong, China. pingcleung@cuhk.edu.hk.
Ping Chung
PC
Leung
Institute of Chinese Medicine and Partner State Key Laboratory of Phytochemistry and Plant Resources in West China, The Chinese University of Hong Kong, New Territories, Hong Kong, China. claralau@cuhk.edu.hk.
Clara Bik San
CB
Lau
Department of Chemistry, Institute of Creativity, and Partner State Key Laboratory of Environmental and Biological Analysis, The Hong Kong Baptist University, Kowloon, Hong Kong, China. hinciwong@gmail.com.
Chi-Hin
CH
Wong
Faculty of Dentistry, The University of Hong Kong, 34 Hospital Road, Hong Kong, China. nisdabendan@gmail.com.
Ka Yan
KY
Pang
Institute of Chinese Medicine and Partner State Key Laboratory of Phytochemistry and Plant Resources in West China, The Chinese University of Hong Kong, New Territories, Hong Kong, China. cwwong_eric@cuhk.edu.hk.
Chun Wai
CW
Wong
Institute of Chinese Medicine and Partner State Key Laboratory of Phytochemistry and Plant Resources in West China, The Chinese University of Hong Kong, New Territories, Hong Kong, China. elaine.wat@cuhk.edu.hk.
Elaine
E
Wat
Faculty of Dentistry, The University of Hong Kong, 34 Hospital Road, Hong Kong, China. ljjin@hku.hk.
Lijian
L
Jin
Scutellaria baicalensis; antimicrobials; chlorhexidine; nanotechnology; oral biofilms; traditional Chinese medicine