Some potential applications of core-shell structured particles:
Microparticles can be encapsulated with a polymer shell By means of Layer-by-Layer (LbL) technology. This shell is semi-permeable: molecules under 5000 g/mol can diffuse into/out of the particle by using certain triggers. This application is especially of interest for targeted drug delivery.
In addition, the core-shell principle and LbL technology can help create particles with functionalities that interact with each other (e.g., by fluorescence resonance energy transfer (FRET) or enzymatic interactions).
Furthermore, polymer microparticles (PS, PMMA, etc.) can be coated with a melamine-formaldehyde shell of 500 nm to several µm in thickness. In this case, the core and the shell can be labelled with different fluorescent dyes (Fig. 2-4).
Figure: Confocal Laser Scanning Microscopy (CLSM) images of core-shell particles:
1) CLSM overlay image of Rhodamine dyed MF particles (7 µm) coated with a 12 nm thick LbL layer labelled with Cy5 (image size 43 x 43 µm)
2) PMMA-core (3 µm) labeled with coumarin 6
3) MF-shell (1.5 µm) labeled with Rhodamine B
4) The whole core-shell structure: overlay of the two channelsBack to overview