Antibacterial and Antibiofouling Properties of Light Triggered Fluorescent Hydrophobic Carbon Quantum Dots Langmuir–Blodgett Thin Films

Abstract

Inimitable properties of carbon quantum dots as well as a cheap production contribute to their possible application in biomedicine especially as antibacterial and antibiofouling coatings. Fluorescent hydrophobic carbon quantum dots are synthesized by bottom-up condensation method and used for deposition of uniform and homogeneous Langmuir−Blodgett thin films on different substrates. It is found that this kind of quantum dots generates singlet oxygen under blue light irradiation. Antibacterial and antibiofouling testing on four different bacteria strains (Escherichia coli, Staphylococcus aureus, Bacillus cereus, and Pseudomonas aeruginosa) reveals enhanced antibacterial and antibiofouling activity of hydrophobic carbon dots thin films under blue light irradiation. Moreover, hydrophobic quantum dots show noncytotoxic effect on mouse fibroblast cell line. These properties enable potential usage of hydrophobic carbon quantum dots thin films as excellent antibacterial and antibiofouling coatings for different biomedical applications.

Structural, mechanical, and antibacterial features of curcumin/polyurethane nanocomposites

“…Surfaces with higher roughness or with high aspect ratios are more pronounced for bacterial adherence but there are some reports that bacteria can adhere to even very smooth surface. In our previous reports we established that Langmuir–Blodgett hydrophobic carbon quantum dots thin films with very low surface roughness (0.2 nm) effectively eradicate both Gram positive and Gram negative bacteria . These Cur/PU nanocomposite surfaces have 10 times higher surface roughness (2.27 nm) and it will be shown below that they have very strong antibacterial activity.…”

“…Antibacterial activity was evaluated according to ISO 22196 standard . Sample dimension was 25 × 25 mm 2 .…”

“…The number of viable bacteria recovered per cm 2 per test specimen ( N ) and antibacterial activity were calculated by equations given in Ref. . Testing was performed in three experiments, each with four repetitions.…”

Rejuvenated Photodynamic Therapy for Bacterial Infections

“…Various PS‐loaded/embedded substrates have been developed successfully, and they show great potential to overcome persistent infections induced by bacterial biofilm . Marković and co‐workers synthesized Langmuir–Blodgett thin films deposited with hydrophobic carbon quantum dots for PDAT against Escherichia coli biofilms under blue‐light irradiation; the films can be used as excellent antibacterial coatings for biomedical implants and devices, wound dressing, and band‐aid …”

Self-assembly of carbon based nanoparticles films by Langmuir-Blodgett method

“…Stanković et al prepared by LB technique uniform and homogeneous CQDs thin films. 226 Composition of CQDs was tuned, so that high concentration and stable colloid of CQDs in chloroform was produced. These authors investigated possible antibacterial activity of CQDs films against S. aureus and E. coli.…”