PDF Publication Title:
Text from PDF Page: 004
Molecules 2019, 24, 2692 4 of 17 until the liquid completely disappeared. The Zeta potential of the UCNPs was determined by Zeta potential instrument (Zetasizer, Nano-Z, Malvern Instruments Limited, UK). The absorption spectrum of the sample was tested by UV-visible spectrophotometer Shimadzu UV-1800 (Shimadzu Co., Kyoto, Japan); SENS-9000 spectrometer (Zolix Instruments Co. Ltd., Beijing, China) is used to measure the excitation and emission spectra of the samples. The Andor Shamrock SR-750 spectrometer (Andor Technology Ltd., Tokyo, Japan) was used to test the up-conversion spectra of nanoparticles with a continuous 980 nm diode laser, and the upconversion signals were collected by photomultiplier tubes and monochromators. The detection range was set from 300 nm to 750 nm. 2.4. Dark Cell Toxicity of Mn-Doped UCNPs L929 mouse fibroblasts were selected to detect dark cytotoxicity. The cells were obtained from the Institute of Biochemistry and Cell Biology of the Chinese Academy of Sciences (Shanghai, China) and approved by the Institutional Review Board of the Jilin University School of Dentistry. Fibroblasts were cultured in DMEM medium (HyClone, Logan, UT, USA) containing 1% antibiotics (100 U/mL penicillin and 100 μg/mL streptomycin) and 10% fetal bovine serum (Gibco, Carlsbad, CA, USA). The culture temperature of the cells was 37 ◦C, and the atmosphere contains 5% CO2. For the dark cytotoxicity of NaYF4:Yb3+,Er3+@Ce6@silane, L929 cells were incubated in 96-well plate at a density 5000 cells per well for 24 h. Then the cells were incubated with different concentration of NaYF4:Yb3+,Er3+@Ce6@silane for another 24 h in darkness. The cell viability was determined by CCK-8 assay (7sea biotech Ltd., Shanghai, China) following the instructions. Wells without any nanoparticles served as calibrators. The percentage survival was calculated and based on the control sample without any treatment as being 100%. All measurements were tested in three replicates. 2.5. Bacterial Culture All three bacterial species were purchased from the American Type Culture Collection (ATCC, Manassas, VA): Porphyromonas gingivalis (P. gingivalis, ATCC 33277), Prevotella intermedia (P. intermedia, ATCC) and Fusobacterium nucleatum (F. nucleatum, ATCC 25586). The use of bacterial species was approved by the Institutional Review Board of the Jilin University School of Dentistry. All bacteria were cultured under anaerobic conditions of 80% N2, 10% H2 and 10% CO2 cultured with tryptic soy broth (TSB, Sigma-Aldrich, St. Louis, MO, USA) supplemented with vitamin K (1 mg/L), L-cysteine hydrochloride (0.5 g/L, Sigma-Aldrich), yeast extract (5 g/L, Sigma-Aldrich) and hemin (5 mg/L, Sigma-Aldrich). 2.6. aPDT of NaYF4@Ce@Silane Against Biofilm Formation On Dentin Squares Caries-free human molars were extracted for the preparation of dentin samples, which was approved by the Institutional Review Board of the Jilin University School of Dentistry (Ref. H20170062), serving as the substrates for biofilm formation. A square dentin sample of 5 × 5 mm (thickness of about 1 mm) was prepared and ground with silicon carbide paper, and then sterilized by autoclaving (134 ◦C, 15 min). Before every experiment, UV light for 30 minutes was involved and followed by immersion in saliva at 37 ◦C for 2 h to pre-coat the saliva film. A saliva sample was prepared from the mixed saliva from fifteen healthy donors who had not taken any antibiotics for 3 months. The saliva from the donors follows the requirements that there was no teeth brushing for 24 h and no food/beverage for 2 h before donating. Cell debris was removed from saliva by centrifugation of 3000 rpm for 20 min. A sterile 0.22 μm filter was used to filtrate the supernatant for sterilization (VWR International, Radnor, PA, USA). Salivary pellicle on dentin disks was prepared by immersing the disk in sterile saliva (37 ◦C) [22]. Three single-strain biofilms were prepared with each bacteria species [22]. Each species was inoculated (108 CFU/mL) onto a salivary pellicle-coated dentin square in a 24-well plate. Then NaYF4@Ce@silane and Mn doped UCNPs were used to treat the samples with a concentration of 100 μg/mL. Then, it was irradiated with a 980 nm laser at 750 J·cm−2 for 3 min. The medium containingPDF Image | Anti-Biofilm Property of Bioactive Upconversion Nanocomposites
PDF Search Title:
Anti-Biofilm Property of Bioactive Upconversion NanocompositesOriginal File Name Searched:
molecules-24-02692.pdfDIY PDF Search: Google It | Yahoo | Bing
Cruise Ship Reviews | Luxury Resort | Jet | Yacht | and Travel Tech More Info
Cruising Review Topics and Articles More Info
Software based on Filemaker for the travel industry More Info
The Burgenstock Resort: Reviews on CruisingReview website... More Info
Resort Reviews: World Class resorts... More Info
The Riffelalp Resort: Reviews on CruisingReview website... More Info
CONTACT TEL: 608-238-6001 Email: greg@cruisingreview.com (Standard Web Page)