Photonic Shell-Crosslinked Nanoparticle Probes for Optical Imaging and Monitoring

Lee, Nam S.; Neumann, William L.; Freskos, John N.; Marzan, Tim Andres; Shieh, Jeng J.; Dorshow, Richard B.; Wooley, Karen L.

doi:10.1364/biomed.2008.bsua5

Cited by 1 publication

(4 citation statements)

References 4 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…We attribute this behavior to the additional hydrophobic linker beads in the crosslinked shell, which lead to larger self-repulsion between polymer beads and increase the instability of the shell. Further, both, the chemical and architectural properties of linker molecules play an important role in the dynamic stability of the crosslinked structure [14][15][16][17][18][19] . The increase of the linker length or the incompatibility between linker and other beads will increase self-diffusion.…”

Section: Effect Of Crosslinking On Swelling Of Microcapsulesmentioning

confidence: 99%

“…Our simulations indicate that for a crosslinked block copolymer microcapsule, the swelling rate of the shell depends on the rigidity of the network structure and the sensitivity of functional groups. Through external stimuli the crosslinking mechanically stabilizes the structure, while the functional groups provide driving forces for opening and closing of the shell [15][16][17][18][30][31][32] . To induce controlled swelling, a pH difference which protonates/deprotonates essentially all pH-sensitive groups is also needed 33 .…”

Section: Effect Of Block Interaction On Swelling Of Microcapsulesmentioning

confidence: 99%

“…To improve the stability of the nanostructure, covalent crosslinking between block copolymers has been developed as an effective method for creating nano-objects with very long retention times 4,13 . A number of block copolymer multicompartment micelles with crosslinked core or shell domains have been tested for enhancing their dynamical and structural stabilities in response to stimulation 10,[14][15][16][17][18][19] . In addition to enhancing stability, the linker molecules can add functionality, and cargo loading could be improved 10,[14][15][16][17][18][19] .…”

Section: Introductionmentioning

confidence: 99%

“…A number of block copolymer multicompartment micelles with crosslinked core or shell domains have been tested for enhancing their dynamical and structural stabilities in response to stimulation 10,[14][15][16][17][18][19] . In addition to enhancing stability, the linker molecules can add functionality, and cargo loading could be improved 10,[14][15][16][17][18][19] . Crosslinking can also lead to a loss of permeability, fluidity, and bendability of the microcapsule shell due to increased mechanical stress and fluid induced viscous stress 20 .…”

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Tunable Permeability of Cross-Linked Microcapsules from pH-Responsive Amphiphilic Diblock Copolymers: A Dissipative Particle Dynamics Study

Wang

Gao²,

Ustach

et al. 2017

Langmuir

View full text Add to dashboard Cite

Using dissipative particle dynamics simulation, we probe the tunable permeability of cross-linked microcapsules made from pH-sensitive diblock copolymers poly(ethylene oxide)-b-poly(N,N-diethylamino-2-ethyl methacrylate) (PEO-b-PDEAEMA). We first examine the self-assembly of non-cross-linked microcapsules and their pH-responsive collapse and then explore the effects of cross-linking and block interaction on the swelling or deswelling of cross-linked microcapsules. Our results reveal a preferential loading of hydrophobic dicyclopentadiene (DCPD) molecules in PEO-b-PDEAEMA copolymers. Upon reduction of pH, non-cross-linked microcapsules fully decompose into small wormlike clusters as a result of large self-repulsions of protonated copolymers. With increasing degree of cross-linking, the morphology of the microcapsule becomes more stable to pH change. The highly cross-linked microcapsule shell undergoes significant local polymer rearrangement in acidic solution, which eliminates the amphiphilicility and therefore enlarges the permeability of the shell. The responsive cross-linked shell experiences a disperse-to-buckle configurational transition upon reduction of pH, which is effective for the steady or pulsatile regulation of shell permeability. The swelling rate of the cross-linked shell is dependent on both electrostatic and nonelectrostatic interactions between the pH-sensitive groups as well as the other groups. Our study highlights the combination of cross-linking structure and block interactions in stabilizing microcapsules and tuning their selective permeability.

show abstract