Phenotiazinium Dyes as Photosensitizers (PS) in Photodynamic Therapy (PDT): Spectroscopic Properties and Photochemical Mechanisms

Effect of Photodynamic Therapy on Microorganisms Responsible for Dental Caries: A Systematic Review and Meta-Analysis

“…This PS efficiency in PDT is related to its intense absorption in the UV-visible region, whose maximum absorption wavelength is 664 nm, within the spectral region of 600 to 1000 nm (phototherapeutic window). It allows for the deep penetration of light in the biological tissues and expressive quantum yield for singlet oxygen formation [61,62]. The literature has already established the action of PDT mediated by MB, presenting its action against several bacteria associated with oral diseases [63,64].…”

Daylight photodynamic therapy with methylene blue in plane warts: a randomized double‐blind placebo‐controlled study

“…The characteristic color of MB is caused by the strong absorption band in the 550-700 nm region. Methylene blue has shown in vivo activity against several types of tumors when locally injected and illuminated with red laser light (6,7).…”

“…The efficacy of daylight-PDT using liposomal-loaded MB was explained by several mechanisms of action, antiproliferative and antiviral mechanisms, in which selective accumulation of PS in more rapidly proliferated HPV-infected keratinocytes leads to destruction of infected keratinocytes and inactivation of non-enveloped viral particles through binding of PS molecules to the viral surface glycoproteins and inhibiting early phases of viral replication. Generation of singlet oxygen and free oxygen radicals will inactivate viruses by damaging and/or cross-linking the nucleic acid and proteins resulting in destruction of keratinocytes via selective apoptosis (7,9). Furthermore, there is release of inflammatory mediators (IL-2, IL-1beta and TNF-alpha) due to the ability of PDT to induce a localized specific immune response as reported by Giomi et al in their study on genital warts (13).…”

“…We believe that MB is an excellent alternative as the advantages of MB include its high safety profile, low cost as it is routinely available in hospital pharmacies. It is worth mentioning that it may be a preferred choice for cutaneous superficial lesions as MB has a strong absorption at wavelengths longer than 620 nm, where light penetration into tissues is optimal (7).…”

Combined effects of photodynamic therapy and irrigants in disinfection of root canals

“…In the present study phenothiazine dye methylene blue was used as the photosensitizer due to its reliable antimicrobial action against vancomycin resistant E. faecalis at an affordable cost [21]. In the present study, the effect of common endodontic irrigants and PDT has been explored.…”