Fig. 4

A Growth survival of (A1) E. coli and (A2) MRSA bacteria. Data are presented as means ± SDs (n = 6). ^*p < 0.05, ^**p < 0.01. B CFU amount of (B1) E. coli and (B2) MRSA bacteria. C Photographs of (C1) E. coli and (C2) MRSA bacterial colonies formed on lysogeny broth (LB)-agar plates. D Representative CLSM images of live/dead staining assay for E. coli (left) and MRSA (right) after different treatments via SYTO9 (green, viable bacteria) and PI (red, dead bacteria) staining. Group I: control group in the absence of NFs and NIR irradiation; Group II: NIR group with the irradiation of NIR laser (808 nm, 1.5 W cm⁻², 10 min) in the absence of NFs; Group III: Cu₃SnS₄ group with the treatment with Cu₃SnS₄ NFs under no laser irradiation; Group IV: Cu₃SnS₄ + NIR group with the treatment with Cu₃SnS₄ NFs plus NIR irradiation (808 nm, 1.5 W cm⁻², 10 min). All groups were exposed to visible light for 20 min