TY  - JOUR
A1  - Hoang, Hoa T.
A1  - Haubitz, Toni
A1  - Kumke, Michael Uwe
T1  - Photophysics of "Floppy" Dyadsas Potential Biomembrane Probes
JF  - Journal of fluorescence
N2  - In the study a dyad (C6 probe), constructed of two dyes with highly different hydrophobicities, was investigated by steady-state and time-resolved spectroscopic techniques in chloroform, methanol, and in phospholipid vesicles, respectively. The dyad was built on two dyes: the lipophilic benzo[a]pyrene (BaP) and the hydrophilic sulforhodamine B (SRB). The dyes were linked via a short, but flexible alkyl chain (six C-atoms). Based on their spectroscopic properties, BaP and SRB showed a very efficient non-radiative resonance energy transfer in solution. Incorporation into a lipid bilayer limited the relative flexibility (degree of freedom) between donor and acceptor and was used for the investigation of fundamental photophysical aspects (especially of FRET) as well as to elucidate the potential of the dyad to probe the interface of vesicles (or cells). The location of the two dyes in vesicles and their respective accessibility for interactions with dye-specific antibodies was investigated. Based on the alteration of the anisotropy, on the rotational correlation time as well as on the diffusion coefficient the incorporation of the C6 probe into the vesicles was evaluated. Especially the limitation in the relative movements of the two dyes was considered and used to differentiate between potential parameters, that influence the energy transfer in the dyad. Transient absorption spectroscopy (TAS) and pulsed-interleave single molecule fluorescence experiments were performed to better understand the intramolecular interactions in the dyad. Finally, in a showcase for a biosensing application of the dyads, the binding of an SRB-specific antibody was investigated when the dyad was incorporated in vesicles.
KW  - Forster resonance energy transfer(FRET)
KW  - Antibody binding
KW  - Vesicles
KW  - Anisotropy
KW  - Fluorescence correlation
KW  - Single molecule fluorescence
KW  - Transient absorption
KW  - Pulsed interleaved excitation
Y1  - 2018
U6  - https://doi.org/10.1007/s10895-018-2286-4
SN  - 1053-0509
SN  - 1573-4994
VL  - 28
IS  - 5
SP  - 1225
EP  - 1237
PB  - Springer
CY  - New York
ER  - 
TY  - JOUR
A1  - Sevostianov, Igor
A1  - Bruno, Giovanni
T1  - Maxwell scheme for internal stresses in multiphase composites
JF  - Mechanics of Materials
N2  - The paper focuses on the reformulation of classic Maxwell's (1873) homogenization method for calculation of the residual stresses in matrix composites. For this goal, we equate the far fields produced by a set of inhomogeneities subjected to known eigenstrains and by a fictitious domain with unknown eigenstrain. The effect of interaction between the inhomogeneities is reduced to the calculation of the additional field acting on an inhomogeneity due to the eigenstrains in its neighbors. An explicit formula for residual stresses is derived for the general case of a multiphase composite. The method is illustrated by several examples. The results are compared with available experimental data as well as with predictions provided by the non-interaction approximation (Eshelby solution). It is shown that accounting for interaction can explain many experimentally observed phenomena and is required for adequate quantitative analytical modeling of the residual stresses in matrix composites.
KW  - Residual stress
KW  - Multiphase composites
KW  - Interaction
KW  - Micromechanical schemes
KW  - Anisotropy
Y1  - 2018
U6  - https://doi.org/10.1016/j.mechmat.2018.12.005
SN  - 0167-6636
SN  - 1872-7743
VL  - 129
SP  - 320
EP  - 331
PB  - Elsevier
CY  - Amsterdam
ER  -