A functionalized surface modification with vanadium nanoparticles of various valences against implant-associated bloodstream infection

Figures & data

Figure 1 SEM morphology of various surfaces of samples V0 (A), V3 (B), V4 (C), and V5 (D).

Abbreviations: SEM, scanning electron microscopy; V0, homogeneous vanadium metal nanoparticles deposited on quartz glass; V3, homogeneous V₂O₃ nanoparticles deposited on quartz glass; V4, homogeneous VO₂ nanoparticles deposited on quartz glass; V5, homogeneous V₂O₅ nanoparticles deposited on quartz glass.

Figure 2 XRD patterns (A) of samples V0, V3, V4, and V5, accompanied by the V_2p XPS spectra of samples V0 (B), V3 (C), V4 (D), and V5 (E).

Abbreviations: XRD, X-ray diffraction; XPS, X-ray photoelectron spectroscopy; V0, homogeneous vanadium metal nanoparticles deposited on quartz glass; V3, homogeneous V₂O₃ nanoparticles deposited on quartz glass; V4, homogeneous VO₂ nanoparticles deposited on quartz glass; V5, homogeneous V₂O₅ nanoparticles deposited on quartz glass.

Figure 3 Release profiles of vanadium ions from various samples after soaking in DMEM (A), TSB (B), and PBS (C).

Abbreviations: DMEM, Dulbecco’s Modified Eagle’s Medium; TSB, trypticase soy broth; PBS, phosphate-buffered saline; V0, homogeneous vanadium metal nanoparticles deposited on quartz glass; V3, homogeneous V₂O₃ nanoparticles deposited on quartz glass; V4, homogeneous VO₂ nanoparticles deposited on quartz glass; V5, homogeneous V₂O₅ nanoparticles deposited on quartz glass.

Figure 4 Proliferation viability of HFF1 cells after 24-hour culture on the glass, V0, V3, V4, and V5 samples.

Notes: ***P<0.001 vs glass; ^#P<0.05; ^###P<0.001 vs V0; ^$$$P<0.001 vs V3; ^&&&P<0.001 vs V4. Data expressed as means ± standard deviation (n=3). DAPI (blue)- and TRITC-phalloidin (red)-stained fluorescent images of HFF1 cells on the five specimens after 1-day culture.

Abbreviations: V0, homogeneous vanadium metal nanoparticles deposited on quartz glass; V3, homogeneous V₂O₃ nanoparticles deposited on quartz glass; V4, homogeneous VO₂ nanoparticles deposited on quartz glass; V5, homogeneous V₂O₅ nanoparticles deposited on quartz glass; DAPI, 4′,6-diamidino-2-phenylindole; TRITC, tetraethyl rhodamine isothiocyanate.

Figure 5 Qualitative assessment of antiseptic capacity against two types of planktonic bacteria.

Notes: (A) For Staphylococcus aureus, representative pictures of recultivated bacteria colonies on SBA for five samples in the TSB or TSB + GSH culture medium; (B) for Pseudomonas aeruginosa, representative pictures of recultivated bacteria colonies on SBA for five samples in the TSB or TSB + GSH culture medium.

Abbreviations: SBA, sheep-blood agar; TSB, trypticase soy broth; V0, homogeneous vanadium metal nanoparticles deposited on quartz glass; V3, homogeneous V₂O₃ nanoparticles deposited on quartz glass; V4, homogeneous VO₂ nanoparticles deposited on quartz glass; V5, homogeneous V₂O₅ nanoparticles deposited on quartz glass.

Figure 6 Quantitative evaluation for antiseptic property against planktonic bacteria.

Notes: (A) Antibacterial rates of planktonic Gram-positive Staphylococcus aureus for the five specimens in TSB medium; (B) antibacterial rates of planktonic Gram-negative Pseudomonas aeruginosa for the five specimens in TSB medium; (C) antibacterial rates of planktonic Gram-positive S. aureus for the five specimens in TSB + GSH medium; (D) antibacterial rates of planktonic Gram-negative P. aeruginosa for the five specimens in TSB + GSH medium. **P<0.01, ***P<0.001 vs glass; ^#P<0.05, ^###P<0.001 vs V0; $P<0.05, ^$$P<0.01, ^$$$P<0.001 vs V3; ^&&P<0.01, ^&&&P<0.001 vs V4. Data expressed as means ± standard deviation (n=3).

Abbreviations: V0, homogeneous vanadium metal nanoparticles deposited on quartz glass; V3, homogeneous V₂O₃ nanoparticles deposited on quartz glass; V4, homogeneous VO₂ nanoparticles deposited on quartz glass; V5, homogeneous V₂O₅ nanoparticles deposited on quartz glass; Rap, antibacterial rates of planktonic bacteria; TSB, trypticase soy broth; GSH, glutathione.

Figure 7 Quantitative evaluation for antiseptic property against sessile bacteria.

Notes: (A) Antimicrobial rates of adherent Gram-positive Staphylococcus aureus for the five samples in TSB medium; (B) antimicrobial rates of adherent Gram-negative Pseudomonas aeruginosa for the five samples in TSB medium; (C) antimicrobial rates of adherent Gram-positive S. aureus for the five samples in TSB + GSH medium; (D) antimicrobial rates of adherent Gram-negative P. aeruginosa for the five samples in TSB + GSH medium. **P<0.01, ***P<0.001 vs glass; ^#P<0.05, ^###P<0.001 vs V0; ^$$P<0.01, ^$$$P<0.001 vs V3; ^&P<0.05, ^&&&P<0.001 vs V4. Data expressed as means ± standard deviation (n=3).

Abbreviations: V0, homogeneous vanadium metal nanoparticles deposited on quartz glass; V3, homogeneous V₂O₃ nanoparticles deposited on quartz glass; V4, homogeneous VO₂ nanoparticles deposited on quartz glass; V5, homogeneous V₂O₅ nanoparticles deposited on quartz glass; Raa, antibacterial rates of adhered bacteria; TSB, trypticase soy broth; GSH, glutathione.

Figure 8 Qualitative assessment of antimicrobial capacity against adherent bacteria by SEM.

Notes: (A) For Gram-positive Staphylococcus aureus, bacterial morphology and biofilm formation on the five samples in TSB (upper) or TSB + GSH (lower) medium; (B) for Gram-negative Pseudomonas aeruginosa, bacterial morphology and biofilm formation on the five samples in TSB (upper) or TSB + GSH (lower) medium. Magnification ×2,000.

Abbreviations: SEM, scanning electron microscopy; V0, homogeneous vanadium metal nanoparticles deposited on quartz glass; V3, homogeneous V₂O₃ nanoparticles deposited on quartz glass; V4, homogeneous VO₂ nanoparticles deposited on quartz glass; V5, homogeneous V₂O₅ nanoparticles deposited on quartz glass; TSB, trypticase soy broth; GSH, glutathione.

Figure 9 Qualitative assessment of antiseptic property against adherent bacteria by CLSM fluorescence.

Notes: (A) For Gram-positive Staphylococcus aureus, biofilm formation illustrated by live/dead staining results on the five samples in TSB medium with or without GSH antioxidant; (B) for Gram-negative Pseudomonas aeruginosa, biofilm formation illustrated by live/dead staining results on the five samples in TSB medium with or without GSH antioxidant. Magnification ×200.

Abbreviations: CLSM, confocal laser-scanning microscopy; V0, homogeneous vanadium metal nanoparticles deposited on quartz glass; V3, homogeneous V₂O₃ nanoparticles deposited on quartz glass; V4, homogeneous VO₂ nanoparticles deposited on quartz glass; V5, homogeneous V₂O₅ nanoparticles deposited on quartz glass; TSB, trypticase soy broth; GSH, glutathione.

Figure 10 Intracellular ROS levels of Staphylococcus aureus and Pseudomonas aeruginosa on the samples after culturing overnight.

Note: Magnification ×200.

Abbreviations: ROS, reactive oxygen species; V0, homogeneous vanadium metal nanoparticles deposited on quartz glass; V3, homogeneous V₂O₃ nanoparticles deposited on quartz glass; V4, homogeneous VO₂ nanoparticles deposited on quartz glass; V5, homogeneous V₂O₅ nanoparticles deposited on quartz glass.

Figure 11 Hemolysis rate of red blood cells after 24 hours of incubation on the five specimens.

Notes: (A) Erythrocytes were incubated on the five specimens without bacteria; (B) erythrocytes were incubated on the five specimens with Gram-positive Staphylococcus aureus; (C) erythrocytes were incubated on the five specimens with Gram-negative Pseudomonas aeruginosa; (D) interactions of erythrocytes and bacteria upon coexistence in the presence/absence of VO_x films. *P<0.05, ***P<0.001 vs Glass; ^#P<0.05 vs V0. Data expressed as means ± standard deviation (n=3).

Abbreviations: V0, homogeneous vanadium metal nanoparticles deposited on quartz glass; V3, homogeneous V₂O₃ nanoparticles deposited on quartz glass; V4, homogeneous VO₂ nanoparticles deposited on quartz glass; V5, homogeneous V₂O₅ nanoparticles deposited on quartz glass; VO_x, vanadium of various valences.

Scheme 1 Illustration of the fabrication process of samples V0, V3, V4, and V5 by magnetron sputtering.

Abbreviations: RT, room temperature; V0, homogeneous vanadium metal nanoparticles deposited on quartz glass; V3, homogeneous V₂O₃ nanoparticles deposited on quartz glass; V4, homogeneous VO₂ nanoparticles deposited on quartz glass; V5, homogeneous V₂O₅ nanoparticles deposited on quartz glass.