POLYELECTROLYTE MULTILAYER CAPSULE: A REVIEW

Article history A few years ago a novel techniques for vesicle called as polyelectrolyte multilayer (PEM) capsule was introduced in the field of drug delivery. Multifunctional polyelectrolyte capsules fabricated by the layer-by-layer (LBL) assembly technique possess remarkable properties, even though they are held together by electrostatic attraction. From the beginning of the nineties controlled radical polymerization techniques such as Atom Transfer Radical Polymerization and Nitroxide mediated Polymerization have used as new tool in polymer chemistry field of drug delivery. Electrostatic interaction between polyelectrolyte and charged surfaces are basis for the formation of multilayer of polyelectrolyte by using alternate charge. The colloidal core can be varied in diameter from 0.1 to 10µm. The thickness of the shell can be in nanometer range by varying the adsorption condition and number of layer. The unique colloidal structure of LBL assembled capsules offers a very versatile platform for encapsulation, storage and delivery of diverse substances. Mobile pH-sensors are developed for monitoring the local pH inside living cells. Ion sensors are obtained by encapsulation of ion-sensitive fluorophores-conjugated dextran into the multilayer microcapsules. The LBL multilayer capsules are coated with kinesin, which can drive cargos such as vesicles, proteins, and organelles along microtubules. The use of polyelectrolyte capsules as carrier in pharmaceutical products, capsules stable for extended periods of time (years) should be developed.