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

Author(s):Show less -

Hurtado, Carolina Ramos ^{[1, 2, 3]} ; Hurtado, Gabriela Ramos ^{[4, 5]} ; de Cena, Gabrielle Lupeti ^[3] ; Queiroz, Rafaela Campos ^{[1, 2]} ; Silva, Alexandre Vieira ^[6] ; Diniz, Milton Faria ^[7] ; dos Santos, Veronica Ribeiro ^[8] ; Trava-Airoldi, Vladimir ^[9] ; Baptista, Mauricio da Silva ^[10] ; Tsolekile, Ncediwe ^{[11, 12]} ; Oluwafemi, Oluwatobi Samuel ^{[11, 12]} ; Conceicao, Katia ^[3] ; Tada, Dayane Batista ^[2]

Affiliation:Show less -

^[1] Fed Inst Sao Paulo IFSP, BR-12223201 Sao Jose Dos Campos, SP - Brazil

^[2] Fed Univ Sao Paulo UNIFESP, Inst Sci & Technol, Nanomat & Nanotoxicol Lab, BR-12231280 Sao Jose Dos Campos, SP - Brazil

^[3] Fed Univ Sao Paulo UNIFESP, Inst Sci & Technol, Peptide Biochem Lab, BR-12231280 Sao Jose Dos Campos, SP - Brazil

^[4] Sao Paulo State Univ UNESP, Inst Sci & Technol, BR-12247004 Sao Jose Dos Campos, SP - Brazil

^[5] Sao Paulo State Univ UNESP, Inst Adv Sea Studies IEAMAr, BR-12247004 Sao Jose Dos Campos, SP - Brazil

^[6] Helmholtz Zentrum Munchen, Inst Med Chem, D-30167 Hannover - Germany

^[7] Technol Inst Aeronaut ITA, Fundamental Sci Div, BR-12228900 Sao Jose Dos Campos, SP - Brazil

^[8] Fed Univ Sao Paulo UNIFESP, Inst Sci & Technol, Bioceram Lab, BR-12231280 Sao Jose Dos Campos, SP - Brazil

^[9] Natl Inst Space Res INPE, Sensors & Mat Associated Lab, BR-12227010 Sao Jose Dos Campos, SP - Brazil

^[10] Univ Sao Paulo, Inst Chem, Dept Biochem, BR-05508000 Sao Paulo, SP - Brazil

^[11] Univ Johannesburg, Dept Chem Sci, POB 17011, ZA-2028 Johannesburg - South Africa

^[12] Univ Johannesburg, Ctr Nanomat Sci Res, ZA-2028 Johannesburg - South Africa

• Document type: Journal article
• Source: NANOMATERIALS; v. 11, n. 6 JUN 2021.
• Web of Science Citations: 0

Abstract

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). (AU)

• FAPESP's process: 19/09737-2 - Enhancement of antimicrobial activity of nanodiamonds by surface functionalization
• Grantee: Rafaela Campos Queiroz
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• FAPESP's process: 19/20111-8 - Evaluation of photoactivity of porphyrin-conjugated ternary quantum dots
• Grantee: Dayane Batista Tada
• Support Opportunities: Research Grants - Visiting Researcher Grant - International
• FAPESP's process: 17/01697-6 - Synthesis and functionalization of bimetallic nanoparticles for application in photodynamic therapy of cancer
• Grantee: Dayane Batista Tada
• Support Opportunities: Regular Research Grants