Potentiation by potassium iodide using TPPS4 for antimicrobial photodynamic inactivation

Liyi Huang; Michael R. Hamblin

doi:10.1117/12.2285246

8 March 2018 Potentiation by potassium iodide using TPPS4 for antimicrobial photodynamic inactivation

Liyi Huang, Michael R. Hamblin

Proceedings Volume 10479, Light-Based Diagnosis and Treatment of Infectious Diseases; 1047918 (2018) https://doi.org/10.1117/12.2285246
Event: SPIE BiOS, 2018, San Francisco, California, United States

Abstract

Potassium iodide can potentiate antimicrobial photodynamic inactivation (aPDI) of a broad-spectrum of microorganisms, producing many extra logs of killing. We compared two charged porphyrins, TPPS4 (thought to be anionic and not able to bind to Gram-negative bacteria) and TMPyP4 (considered cationic and well able to bind to bacteria). As expected TPPS4 + light did not kill Gram-negative Escherichia coli, but surprisingly when 100 mM KI was added, it was highly effective at mediating aPDI (eradication at 200 nM + 10 J/cm² of 415 nm light). TPPS4 was more effective than TMPyP4 in eradicating the Gram-positive bacteria, methicillin-resistant Staphylococcus aureus and the fungal yeast Candida albicans (regardless of KI). TPPS4 was also highly active against E. coli after a centrifugation step when KI was added, suggesting that the supposedly anionic porphyrin bound to bacteria and Candida. We conclude that TPPS4 behaves as if it has some cationic character in the presence of bacteria, which may be related to its supply from vendors in the form of a dihydrochloride salt.

Conference Presentation

Citation Download Citation

Liyi Huang and Michael R. Hamblin "Potentiation by potassium iodide using TPPS4 for antimicrobial photodynamic inactivation", Proc. SPIE 10479, Light-Based Diagnosis and Treatment of Infectious Diseases, 1047918 (8 March 2018); https://doi.org/10.1117/12.2285246

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available