Morphological Evolution of Strongly Fluorescent Water Soluble AIEEgen-Triblock Copolymer Mixed Aggregates with Shape-Dependent Cell Permeability.
Soumyadipta RakshitSharmistha DasVinodhini GovindarajRatika MainiAnil KumarAnindya DattaPublished in: The journal of physical chemistry. B (2020)
Dimethyl-2,5-bis(4-methoxyphenylamino)terephthalate (DBMPT) is a water-insoluble fluorogenic molecule, which has been rendered water-soluble in physiological conditions, by the addition of triblock copolymers (TBPs), P123 (PEO19PPO69PEO19), and F127 (PEO100PPO65PEO100). DBMPT-TBP mixed aggregates, formed in the process, exhibit significant aggregation-induced enhancement of emission, with nanosecond fluorescence lifetimes. Dynamics involved in suppression of nonradiative pathways and consequent enhancement of fluorescence are followed by femtosecond transient absorption and time-resolved fluorescence spectroscopic techniques. Interestingly, shapes of the aggregates formed with the two TBPs are found to be very different, even though they differ only in the length of hydrophilic blocks. DBMPT-P123 aggregates are micrometer-sized and spherical, while DBMPT-F127 aggregates form nanorods. Evolution of their morphologies, as a function of TBP concentration, is monitored using cryo-TEM, FESEM, and fluorescence lifetime imaging microscopy. Fluorescence lifetime distribution provides useful insight into microheterogeneity in these mixed aggregates. Excellent cell permeability is observed for DBMPT-F127 nanorods, in contrast to DBMPT-P123 microspheres. These fluorescent nanorods exhibit the ability to mark lipid droplets within the cell and hence bear the promise for application in intracellular imaging.
Keyphrases
- water soluble
- single molecule
- high resolution
- single cell
- energy transfer
- cell therapy
- living cells
- quantum dots
- reduced graphene oxide
- endothelial cells
- magnetic resonance
- high throughput
- mass spectrometry
- drug delivery
- blood brain barrier
- label free
- brain injury
- machine learning
- magnetic resonance imaging
- ionic liquid
- artificial intelligence
- big data