☆ 4.7 Article

Diamond Nanoparticles-Porphyrin mTHPP Conjugate as Photosensitizing Platform: Cytotoxicity and Antibacterial Activity

NANOMATERIALS (2021)

Journal

NANOMATERIALS

Volume 11, Issue 6, Pages -

Publisher

MDPI

DOI: 10.3390/nano11061393

Keywords

photosensitizers (PS); nanoconjugate; photodynamic antimicrobial therapy (aPDT); drug-resistance

Funding

Fundacao de Amparo ao Ensino e Pesquisa do Estado de Sao Paulo [2017/01697-6, 2019/20111-8, 2019/09737-2]

Ask authors/readers for more resources

Protocol

Community support

Reagent

Community support

Automated Summary New
Abstract

The conjugation of diamond nanoparticles with the photosensitizer Meso-5, 10, 15, 20-tetrakis (3-hydroxyphenyl) phorphyryn (mTHPP) showed promising antibacterial activity against Escherichia coli, while also demonstrating non-cytotoxic effects on murine embryonic fibroblast cells. These results suggest that the ND-mTHPP nanoconjugate could be a potential platform for antimicrobial photodynamic therapy.

Conjugation of photosensitizers (PS) with nanoparticles has been largely used as a strategy to stabilize PS in the biological medium resulting in photosensitizing nanoparticles of enhanced photoactivity. Herein, (Meso-5, 10, 15, 20-tetrakis (3-hydroxyphenyl) phorphyryn (mTHPP) was conjugated with diamond nanoparticles (ND) by covalent bond. Nanoconjugate ND-mTHPP showed suitable stability in aqueous suspension with 58 nm of hydrodynamic diameter and Zeta potential of -23 mV. The antibacterial activity of ND-mTHPP was evaluated against Escherichia coli for different incubation times (0-24 h). The optimal activity was observed after 2 h of incubation and irradiation (660 nm; 51 J/cm(2)) performed right after the addition of ND-mTHPP (100 mu g/mL) to the bacterial suspension. The inhibitory activity was 56% whereas ampicillin at the same conditions provided only 14% of bacterial growth inhibition. SEM images showed agglomerate of ND-mTHPP adsorbed on the bacterial cell wall, suggesting that the antimicrobial activity of ND-mTHPP was afforded by inducing membrane damage. Cytotoxicity against murine embryonic fibroblast cells (MEF) was also evaluated and ND-mTHPP was shown to be noncytotoxic since viability of cells cultured for 24 h in the presence of the nanoconjugate (100 mu g/mL) was 78%. Considering the enhanced antibacterial activity and the absence of cytotoxic effect, it is possible to consider the ND-mTHPP nanoconjugate as promising platform for application in antimicrobial photodynamic therapy (aPDT).

Authors

I am an author on this paper

Click your name to claim this paper and add it to your profile.

Reviews

Primary Rating

4.7

Not enough ratings

Secondary Ratings

Novelty

Significance

Scientific rigor

Rate this paper

Inherently Antimicrobial P(MMA-ran-DMAEMA) Copolymers Sensitive to Photodynamic Therapy: A Double Bactericidal Effect for Active Wound Dressing

Orlando Santoro, Miryam Chiara Malacarne, Francesco Sarcone, Luca Scapinello, Stefania Pragliola, Enrico Caruso, Viviana Teresa Orlandi, Lorella Izzo

Summary: In this study, two compounds from the BODIPY family were bound to amino-pendant groups of three random copolymers with varying amounts of MMA and DMAEMA. The copolymers showed inherent bactericidal activity due to the presence of amino groups and quaternized nitrogens bound to BODIPY. Coated filter paper discs with copolymers conjugated to BODIPY inhibited the growth of E. coli and S. aureus under green light irradiation, with the highest efficiency observed in the copolymer containing 43% DMAEMA and approximately 0.70 wt/wt% BODIPY. The copolymers also exhibited residual antimicrobial activity after dark incubation.

INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES (2023)