Figure 1.
Scheme of polydopamine coating process on QCM chips surfaces by normal method and rapidly-deposited method.
Substrates are vertically placed in standard dopamine solution at the temperature of 60°C with stirring (300 r·min−1) using our uniquely designed device, which can significantly improve the deposition of polydopamine on QCM chips.
Figure 2.
The influence of temperature and reaction method on the deposition kinetics of polydopamine films.
(A): Representative mass change vs. time (min) curves as a function of temperature for polymerization of dopamine solution. (B): The mass change of QCM chips coated by PDA formed by methods of static, shaking (300 r·min−1) and stirring (300 r·min−1) for 1 h respectively. *Represents p<0.05 and ** Represents p<0.01 compared with chips coated by PDA formed at static group, n = 3.
Figure 3.
The mass and thickness measurement of sPDA films and nPDA films.
(A): The mass change of QCM chips decorated by sPDA films of varying polymerization times (5 min, 10 min, 20 min, 30 min, 1 h, 2 h, 4 h and 8 h) as a function of ultrasonic cleaning time, and compared with that of 24 h-nPDA film coated chips. (B): The film thickness of QCM chips coated by sPDA of different polymerization times (5 min, 10 min, 20 min, 30 min, 1 h, 2 h, 4 h and 8 h) and 24 h-nPDA. Those chips had ultrasonically cleaned in distilled water for 10 min before measurement. ** Represents p<0.01, n = 3.
Figure 4.
Water contact angles of QCM chips modified by sPDA films and nPDA films.
The Contact angles of pristine QCM chips and QCM chips modified by coating of 24 h-nPDA, 5 min-sPDA, 10 min-sPDA, 20 min-sPDA 30 min-sPDA, 1 h-sPDA, 2 h-sPDA, 4 h-sPDA and 8 h-sPDA. All samples were ultrasonically cleaned for 10 min and dried. ** Represents p<0.01 compared with the pristine chips group, n = 3.
Figure 5.
The AFM surface topographies of QCM chips modified by sPDA films and nPDA films.
(A): Pristine chip. (B) 24 h-nPDA decorated chip. (C): 5 min-sPDA decorated chip. (D): 10 min-sPDA decorated chip. (E): 20 min-sPDA decorated chip. (F): 30 min-sPDA decorated chip. (G): 1 h-sPDA decorated chip. (H): 2 h-sPDA decorated chip. (I): 4 h-sPDA decorated chip. (J): 8 h-sPDA decorated chip. All those samples had ultrasonically cleaned in distilled water for 10 min. Scale bar: 200 nm.
Figure 6.
BSA binding evaluation of sPDA films and nPDA films.
Representative mass change vs. time (min) curves of pristine chip, 24 h-nPDA coated chip, 5 min-sPDA coated chip, 10 min-sPDA coated chip, 20 min-sPDA coated chip, 30 min-sPDA coated chip, 1 h-sPDA coated chip, 2 h-sPDA coated chip, 4 h-sPDA coated chip and 8 h-sPDA coated chip reaction with 5 mg·ml−1 BSA solution.
Figure 7.
Cytotoxicity assay of QCM chips modified by 30 min-sPDA films and 24 h-nPDA films.
Viability of MG63 osteoblasts incubated with pristine QCM chips, 30 min-sPDA decorated chips and 24 h-nPDA decorated chips for 24 h and 72 h. Viability is expressed as a percentage relative to the result obtained with the non-toxic control (MG63 osteoblasts incubated without substrates). n = 3.
Figure 8.
Bacterial adhesion on the surface of 30 min-sPDA-CS and 24 h-nPDA-CS decorated Ti and PEEK.
Number of living E.Coli and S.Mutans adhered on decorated Ti and PEEK surfaces after exposed to bacterial suspension for 4 h, 24 h and 72 h. ** represents p<0.01 compared with the pristine group, n = 3.