About this Research Topic
The many biochemical reactions responsible for cellular functions, are fundamentally co-regulated by the intracellular temperature distribution. In addition, the biochemical reactions are exposed to different oxygen conditions depending on the particular areas within cell organelles, at which the reactions take place. Nevertheless, determination of the local temporal variation of the temperature and/or oxygen concentration and/or local pH alternation in biological specimens, either cell-cultures or bacterial biofilms, remains a considerable technological challenge. Strongly limiting factor for all possible sensing techniques is the set of unavoidable requirements: low cell-toxicity of the sensor-material, keeping the photodynamic stress for the living organism on an acceptable level (i.e. low excitation intensity), negligible local heating, avoiding generation of any type of reactive oxygen species (ROS), as consequence of the sensing process or their effective local scavenging.
It seems, that the process of Triplet-Triplet Annihilation Upconversion (TTA-UC), performed in nano-confined environment with aquatic continuous phase has the potential to overcome these severe sensing problems. Even more, the TTA-UC process delivers in real-time regime and fully non-interconnected two optical signals, namely delayed fluorescence (dF) and residual phosphorescence (rPh), as a reaction on the acting external stimuli (modulation of the local temperature and/or alteration of the local concentration of the molecular oxygen, and/or pH change). Current research focuses on optimized encapsulating strategies, synthesis or evaluation of biocompatible sacrificial singlet oxygen scavenging moieties, searching for new upconversion active molecules, combining enhanced optical properties and individual protection against oxygen damaging. The minimally invasive nature of the applied sensing techniques is verified by standard cell-toxicity tests. We welcome Original Research, Review, Mini Review and Perspective articles on themes including, but not limited to:
• Triplet-triplet annihilation upconversion (TTA-UC) in confined environment: encapsulating strategies, sample architecture, sacrificial singlet oxygen scavenging dynamics
• Ratiometric, all-optical minimally invasive temperature and/or oxygen and/or pH sensing
• Synthesis of upconversion materials with optimized absorption / emission properties regarding the tissue transparency window, controlled molecular amphiphilicity and/or equipped with singlet oxygen protective moieties
• Dynamical description of the TTA-UC process in soft-matter environment
• Interplay between sample architecture / sensing properties of nano-confined TTA-UC systems
• Singlet oxygen scavenging moieties, material composition and quantitative protection properties
It seems, that the process of Triplet-Triplet Annihilation Upconversion (TTA-UC), performed in nano-confined environment with aquatic continuous phase has the potential to overcome these severe sensing problems. Even more, the TTA-UC process delivers in real-time regime and fully non-interconnected two optical signals, namely delayed fluorescence (dF) and residual phosphorescence (rPh), as a reaction on the acting external stimuli (modulation of the local temperature and/or alteration of the local concentration of the molecular oxygen, and/or pH change). Current research focuses on optimized encapsulating strategies, synthesis or evaluation of biocompatible sacrificial singlet oxygen scavenging moieties, searching for new upconversion active molecules, combining enhanced optical properties and individual protection against oxygen damaging. The minimally invasive nature of the applied sensing techniques is verified by standard cell-toxicity tests. We welcome Original Research, Review, Mini Review and Perspective articles on themes including, but not limited to:
• Triplet-triplet annihilation upconversion (TTA-UC) in confined environment: encapsulating strategies, sample architecture, sacrificial singlet oxygen scavenging dynamics
• Ratiometric, all-optical minimally invasive temperature and/or oxygen and/or pH sensing
• Synthesis of upconversion materials with optimized absorption / emission properties regarding the tissue transparency window, controlled molecular amphiphilicity and/or equipped with singlet oxygen protective moieties
• Dynamical description of the TTA-UC process in soft-matter environment
• Interplay between sample architecture / sensing properties of nano-confined TTA-UC systems
• Singlet oxygen scavenging moieties, material composition and quantitative protection properties
Keywords: Triplet-Triplet Annihilation Upconversion, Nanoconfined, Water environment, Ratiometric minimally invasive sensing, All-optical
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