Cellular components in proximity via singlet oxygen

Cellular components in proximity via singlet oxygen refers to the collective biomolecules, including proteins, lipids, and nucleic acids, that are targeted by the reactive species singlet oxygen (1O2). This target is central to Photodynamic Therapy (PDT) and proximity labeling technologies like micro-mapping (uMap). In PDT, a photosensitizer is activated by specific wavelengths of light to produce singlet oxygen, which induces oxidative stress and subsequent cell death in the immediate vicinity (typically within 20–100 nm) of the drug. This high spatial precision allows for the selective destruction of malignant tissues while sparing distant healthy cells. In research, this mechanism is leveraged to map protein-protein interactions by labeling only those molecules physically close to a catalyst-tagged protein of interest. Because singlet oxygen is highly reactive and has a very short half-life, its effects are restricted to a small radius, providing high spatial and temporal resolution for both therapeutic and diagnostic applications.

Other names

Singlet oxygen microenvironmentProximal biomoleculesSinglet oxygen-mediated proximity labeling targetPDT target environment

Generation of singlet oxygen (Type II photodynamic reaction) upon light activation, which causes non-specific oxidative damage to nearby proteins, lipids, and DNA within a limited diffusion radius.