Iris Xiaoxue Yin1, Ollie Yiru Yu1, Irene Shuping Zhao2, May Lei Mei3, Quan-Li Li4, Jinyao Tang5, Chun-Hung Chu6. 1. Faculty of Dentistry, The University of Hong Kong, Hong Kong, China. 2. School of Stomatology, Shenzhen University Health Science Center, Shenzhen, China. 3. Faculty of Dentistry, The University of Hong Kong, Hong Kong, China. Electronic address: mei1123@hku.hk. 4. College of Stomatology, Anhui Medical University, Hefei, China. 5. Department of Chemistry, The University of Hong Kong, Hong Kong, China. 6. Faculty of Dentistry, The University of Hong Kong, Hong Kong, China. Electronic address: chchu@hku.hk.
Abstract
OBJECTIVE: To develop silver nanoparticles (AgNPs) using epigallocatechin gallate (EGCG) and evaluate its biocompatibility and inhibition effect on Streptococcus mutans biofilm growth. DESIGN: AgNPs were synthesized using EGCG as a reducing agent. Cytotoxicity was assessed using half-maximal inhibitory concentration (IC50) against human gingival fibroblast (HGF-1) and stem cells from human exfoliated deciduous teeth (SHED). Antibacterial properties were evaluated with minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) against S. mutans. Dentine blocks were treated with AgNPs, silver nitrate (AgNO3), or water before being incubated with S. mutans. The kinetics, morphology and viability of the biofilm at different time points were assessed by colony-forming units (CFUs), scanning electron microscopy (SEM), and confocal laser scanning microscopy (CLSM), respectively. Lactic acid and polysaccharide production of the biofilm were also investigated. RESULTS: Spherical AgNPs with diameter 17 ± 7 nm were developed. The IC50 of AgNPs and AgNO3 against HGF-1 were 44.88 ± 11.39 μg/mL and 11.53 ± 6.96 μg/mL, respectively (p < 0.001), whereas those against SHED were 68.02 ± 24.48 μg/mL and 9.54 ± 6.63 μg/mL, respectively (p = 0.02). The MIC of AgNPs and AgNO3 were 32.22 ± 7.34 μg/mL and 48.89 ± 15.11 μg/mL, respectively (p = 0.01), whereas their MBC was 63.33 ± 11.73 μg/mL and 85.00 ± 20.77 μg/mL, respectively (p = 0.02). Log CFUs of the AgNPs group were the lowest among the groups (p < 0.001). SEM and CLSM found a confluent biofilm in AgNO3 and water groups but not in AgNPs group. Biofilms in AgNPs group was revealed with lowest level of acidic acid and polysaccharides production (p < 0.001). CONCLUSION: This study developed biocompatible AgNPs which inhibited the growth of a cariogenic biofilm.
OBJECTIVE: To develop silver nanoparticles (AgNPs) using epigallocatechin gallate (EGCG) and evaluate its biocompatibility and inhibition effect on Streptococcus mutans biofilm growth. DESIGN:AgNPs were synthesized using EGCG as a reducing agent. Cytotoxicity was assessed using half-maximal inhibitory concentration (IC50) against human gingival fibroblast (HGF-1) and stem cells from human exfoliated deciduous teeth (SHED). Antibacterial properties were evaluated with minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) against S. mutans. Dentine blocks were treated with AgNPs, silver nitrate (AgNO3), or water before being incubated with S. mutans. The kinetics, morphology and viability of the biofilm at different time points were assessed by colony-forming units (CFUs), scanning electron microscopy (SEM), and confocal laser scanning microscopy (CLSM), respectively. Lactic acid and polysaccharide production of the biofilm were also investigated. RESULTS: Spherical AgNPs with diameter 17 ± 7 nm were developed. The IC50 of AgNPs and AgNO3 against HGF-1 were 44.88 ± 11.39 μg/mL and 11.53 ± 6.96 μg/mL, respectively (p < 0.001), whereas those against SHED were 68.02 ± 24.48 μg/mL and 9.54 ± 6.63 μg/mL, respectively (p = 0.02). The MIC of AgNPs and AgNO3 were 32.22 ± 7.34 μg/mL and 48.89 ± 15.11 μg/mL, respectively (p = 0.01), whereas their MBC was 63.33 ± 11.73 μg/mL and 85.00 ± 20.77 μg/mL, respectively (p = 0.02). Log CFUs of the AgNPs group were the lowest among the groups (p < 0.001). SEM and CLSM found a confluent biofilm in AgNO3 and water groups but not in AgNPs group. Biofilms in AgNPs group was revealed with lowest level of acidic acid and polysaccharides production (p < 0.001). CONCLUSION: This study developed biocompatible AgNPs which inhibited the growth of a cariogenic biofilm.
Authors: Gamal M El-Sherbiny; Salwa A Abou El-Nour; Ahmed A Askar; Nasser H Mohammad; Ali A Hammad Journal: Bioprocess Biosyst Eng Date: 2021-10-19 Impact factor: 3.210
Authors: John Yun Niu; Iris Xiaoxue Yin; William Ka Kei Wu; Quan-Li Li; May Lei Mei; Chun Hung Chu Journal: Clin Oral Investig Date: 2021-10-12 Impact factor: 3.573
Authors: Irene Shuping Zhao; Iris Xiaoxue Yin; May Lei Mei; Edward Chin Man Lo; Jinyao Tang; Quanli Li; Lok Yan So; Chun Hung Chu Journal: Int J Nanomedicine Date: 2020-04-23
Authors: Iris Xiaoxue Yin; Irene Shuping Zhao; May Lei Mei; Edward Chin Man Lo; Jinyao Tang; Quanli Li; Lok Yan So; Chun Hung Chu Journal: Int J Nanomedicine Date: 2020-05-06