Table 4.
Biofilm disruptive strategies based on photodynamic therapy.
| Strategy | PS and associated compounds | Light Parameters | Time of exposure | Bacterial strains | Mechanism of action | References |
|---|---|---|---|---|---|---|
| PDT | TMP (10 μM) Vancomycin |
Tungsten lamp WL: 400–800 nm(white light) Power density: 166 mW cm−2 Fluence: 150–200 J cm−2 |
~15–20 min | S. aureus (SA113, V329) MRSA (BH1C) | Bacteria dispersion Increased susceptibility to antibiotic |
Di Poto et al., 2009 |
| ALA (40 mM) |
HPG5000 semiconductor laser WL: 635 nm (red light) Fluence: 0–300 J cm−2 |
- | MRSA (ATCC 43300) MRSE (287) |
Dose-dependent phototoxicity Interference in cell-to-cell and cell-to-matrix interactions | Li et al., 2013 | |
| S-PS (0.5, 1, and 2 μg ml−1)EPIs |
WL: 650 nm Fluences: 5, 10, 15 J cm−2 |
1 h | S. aureus (CMCC 260003)MDR S. aureus (ATCC 29213) | Morphological damage caused by ROS Enhanced antimicrobial efficiency |
Jia et al., 2019 | |
| ALA (10 or 20 mM) |
LED WL: 630 nm(red light) Power density: 90 mW cm−2 Fluence: 108 J cm−2 |
20 min | P. aeruginosa (PAO1) | Dose-dependent growth inhibition and bacterial death Dispersion of the matrix |
Tan et al., 2018b | |
| TBO, Azure A, and New MetB (10 μM) |
WL: 630 nm Power: 100 mW Power density: 0.130 W cm−2 Fluence: 100 J cm−2 |
Maximum time exposure 13 min |
Enterococcus faecalis (MTCC 2729) Klebsiella pneumonia (ATCC700603) |
EPS disruption Reduction of EPS production | Misba et al., 2017 | |
| Tetra-Py+-Me (20 μg) |
13 parallel OSRAM 2' 18 W/840 lamps WL: 380–700 nm (white light) Fluence: Maximum of 64.8 J cm−2 Power density: 4.0 mW cm−2 |
Maximum time exposure 270 min |
S. aureus (ATCC 700699) P. aeruginosa (57) Candida albicans (ATCC 10231) |
Matrix decomposition (decrease of polysaccharides content) | Beirao et al., 2014 | |
| TBO encapsulated in microemulsion(50 – 100 ppm)EDTA (100–500 ppm) |
LED lamps WL: 610 – 630 nm(Red light) Fluence: 0.607 J cm−2 |
15 min |
S. aureus (ATCC 35556) S. epidermidis (ATCC 35984) |
EPS disruption by EDTA chelating effect Enhanced penetration of the PS |
Rout et al., 2018 | |
| ICG and EDTA(2 mM or 5 mM)Vancomycin for MRSAAmikacin for MRPA |
Diode laser WL: 808 nm Power density: 1.5 W cm−2 Fluence: 135 J cm−2 |
90s |
S. aureus (ATCC 25923)MRSA (10485) P. aeruginosa (ATCC 27853)MRPA (10911) |
Formation of bacteria-free voids Bacterial death |
Li X. et al., 2019 | |
| Malachite greenconjugated to carboxyl-functionalized multi-walled carbon nanotubes(50 μg ml−1) |
Red Laser WL: 660 nm Fluence: 58.49 J cm−2 |
3 min |
P. aeruginosa (PAO1) S. aureus(MCC 2408) |
Improved biofilm inhibition EPS inhibitionReduced cell viability |
Anju et al., 2019b | |
| Surface Coating: IR780 (0.02 mg ml−1) MoS2 and arginine-glycine-aspartic acid-cysteine |
WL: 808 nm Power density: 0.5 W cm−2 |
30 s intervals for 10 min | S. aureus (ATCC 29213) | Synergistic PDT/PTT effect(ROS generation/local hyperthermia) | Li M. et al., 2019 | |
| ICG loaded into mesoporous polydopamine NPs |
Laser WL: 808 nm Power density: 0.75 W cm−2 Diameter: 15.6 mm |
600 s | S. aureus (ATCC 29213) | Synergistic PDT/PTT effect (ROS generation/local hyperthermia) | Yuan et al., 2019 | |
| RLP068/Cl (50 μM) |
Diode laser WL: 689 nm Power density: 120 mW cm−2 Fluence: 60 J cm−2 |
~8 min | MRSA (SAUMRBP2) P. aeruginosa (PAE2) |
Decrease in biomass Decrease in the number of viable cells |
Vassena et al., 2014 | |
| MetB (0.3 mM) |
Laser WL: 665 nm Fluence: 35 J cm−2 Power density: 35 mW cm−2 |
16 min |
S. aureus MRSA S. epidermidis P. aeruginosa A. baumannii (sourced from NCTC and ATCC) |
Bactericidal effect Total (or partial) eradication of formed biofilms |
Briggs et al., 2018 |
A. baumannii, Acinetobacter baumannii; ALA, 5-aminolevulinic acid; EDTA, ethylenediaminetetraacetic acid; EPIs, efflux pump inhibitors; EPS, extracellular polymeric substances; ICG, indocyanine green; LED, light-emitting diode; MDR S. aureus, multidrug-resistant Staphylococcus aureus; MetB, methylene blue; MRPA, multidrug-resistant Pseudomonas aeruginosa; MRSA, methicillin-resistant Staphylococcus aureus; MRSE, methicillin-resistant Staphylococcus epidermidis; NPs, nanoparticles; P. aeruginosa, Pseudomonas aeruginosa; PDT, photodynamic therapy; PS, photosensitizer; PTT, photothermal therapy; ROS, reactive oxygen species; S. aureus, Staphylococcus aureus; S. epidermidis, Staphylococcus epidermidis; S-PS, S-porphin sodium; TBO, toluidine blue O; TMP, tetra-substituted N-methyl-pyridyl-porphine; WL, wavelength.