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Science & Evidence Behind Oxafence

Antimicrobial Photodynamic Inactivation (aPDI) refers to the application of well-studied photodynamic principles to microbial control. Photodynamic Therapy (PDT) has been used clinically for decades in diverse medical contexts, and aPDI adapts those principles for microbial interactions with materials. At its core, aPDI involves light-activated protective dyes that interact with surrounding oxygen to generate short-lived reactive oxygen species, most notably singlet oxygen, at the surface where they are applied.

Singlet oxygen is:

  • widely studied in chemistry and biology

  • produced naturally in the environment (e.g., through plant and atmospheric interactions)

  • understood to interact with microbes at the molecular level

  • short-lived and localized in action

This fundamental science provides the basis for Oxafence technology.

Protective Dyes Used in Oxafence

Oxafence formulations incorporate medically understood protective dyes, including Methylene Blue (MB) and Riboflavin (Vitamin B2).

Methylene Blue (MB)

  • Has a long history of use in medicine, including as a textile dye, surgical marking agent, and therapeutic compound.

  • Is on the World Health Organization’s list of essential medicines.

  • When incorporated into materials and exposed to ambient light, participates in singlet oxygen generation.

Riboflavin (Vitamin B2)

  • A naturally occurring nutrient that also acts as a photosensitizer in aPDI contexts.

  • Can be integrated similarly into materials to support light-activated reactions.

Taken together, these protective dyes form the basis of Oxafence’s materials-applied scientific approach.

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Blue cover page of the World Health Organization's Model List of Essential Medicines, 22nd list (2021), featuring the WHO logo at the bottom.

Peer-Reviewed Research & WHO-Linked Studies

Singletto’s scientific foundation is rooted in clinician-led research organized through global collaborations, including work with members of a World Health Organization task force during the COVID-19 pandemic.

The Development of Methods for Mask and N95 Decontamination (DeMaND) study, co-authored by Singletto leadership and international partners, was published in Infection Control and Hospital Epidemiology (2021) and explored mask-based applications of aPDI under relevant use conditions.

Subsequent research was published in the American Journal of Infection Control (2022), including studies led by Singletto co-founder Dr. Thomas Lendvay examining Methylene Blue–based approaches, CDC-researcher–led studies involving high-consequence pathogens such as Ebola, Nipah, and Lassa viruses, and a PPE usage study that included participation from Singletto scientific advisors.

These peer-reviewed studies provide detailed methodology, experimental context, and analysis of how light-activated dye interactions were evaluated in controlled research settings.

Ongoing Research & Collaboration

Singletto’s scientists, virologists, chemists, and clinical collaborators continue to engage with U.S. Military, academic, and institutional partners on expanding the evidence base for materials-applied photodynamic approaches.

This body of work includes contributions from multiple institutions and seeks to broaden understanding of how these principles can interface with materials science, virology, and regulatory pathways.

For the most up-to-date listings of peer-reviewed research, publications, and conference proceedings, consult the journal links above or contact the Singletto science team directly.