Energy-Transfer Schemes To Probe Fluorescent Nanocarriers and Their Emissive Cargo.
A strategy to probe supramolecular nanocarriers and their cargo in the intracellular space was developed on the basis of fluorescence measurements and energy transfer. It relies on the covalent attachment of an energy donor, or acceptor, to the macromolecular backbone of amphiphilic polymers and the noncovalent encapsulation of a complementary acceptor, or donor, in the resulting micelles. In aqueous environments, these macromolecules self-assemble into nanostructured constructs and bring the complementary chromophores in close proximity to enable efficient energy transfer. These supramolecular assemblies travel from the extracellular to the intracellular space and retain their integrity in the process. Indeed, donors and acceptors remain close to each other after internalization, and excitation of the former chromophores translates into significant intracellular emission from the latter. Furthermore, these supramolecular assemblies exchange their components with fast kinetics in aqueous dispersions because of the reversible character of the noncovalent contacts holding them together. As a result, micelles incorporating exclusively the donors and nanocarriers containing only the acceptors scramble their chromophoric building blocks, upon mixing, to allow the transfer of energy. These dynamic processes can be reproduced in the intracellular environment with the sequential incubation of cells with the two sets of complementary nanostructured assemblies. Thus, these operating principles and choice of supramolecular synthons are particularly valuable to monitor self-assembling nanocarriers and their cargo inside living cells and can facilitate the elucidation of the behavior of these promising delivery vehicles in a diversity of biological specimens.
Laboratory for Molecular Photonics, Department of Chemistry, University of Miami , 1301 Memorial Drive, Coral Gables, Florida 33146-0431, United States.
Ek Raj
ER
Thapaliya
School of Pharmacy and Pharmaceutical Sciences, University of Ulster , Coleraine BT52 1SA, Northern Ireland, United Kingdom.
Colin
C
Fowley
School of Pharmacy and Pharmaceutical Sciences, University of Ulster , Coleraine BT52 1SA, Northern Ireland, United Kingdom.
Bridgeen
B
Callan
Laboratory for Molecular Photonics, Department of Chemistry, University of Miami , 1301 Memorial Drive, Coral Gables, Florida 33146-0431, United States.
Sicheng
S
Tang
Laboratory for Molecular Photonics, Department of Chemistry, University of Miami , 1301 Memorial Drive, Coral Gables, Florida 33146-0431, United States.
Yang
Y
Zhang
School of Pharmacy and Pharmaceutical Sciences, University of Ulster , Coleraine BT52 1SA, Northern Ireland, United Kingdom.
John F
JF
Callan
Laboratory for Molecular Photonics, Department of Chemistry, University of Miami , 1301 Memorial Drive, Coral Gables, Florida 33146-0431, United States.
Françisco M
FM
Raymo
D004337:Drug Carriers / Q000737:chemistry*; D004735:Energy Transfer; D005453:Fluorescence; D006367:HeLa Cells; D006801:Humans; D015394:Molecular Structure; D053758:Nanoparticles / Q000737:chemistry*
D004337:Drug Carriers