This review presents use of the microfluidics technique for the preparation of polylactide (PLA) based particles for developing novel drug delivery systems. Droplet-based microfluidics allow uniform single, double and higher order emulsions to be generated that yield highly uniform microspheres, microcapsules and polymersomes. Typically, the building blocks of these complex microparticle systems are PLA macromolecules, their copolymers with different comonomers and recently stereocomplexes composed of an equimolar mixture of poly(L-lactide) and poly(D-lactide). In addition, the technique offers several advantages over conventional emulsion methods and the highly uniform droplets obtained allow for encapsulation of small drug molecules in polymer network meshes or within their hollow interior. The novel approach in this area is to use the microfluidics technique to produce nanoparticles in the microfluidics channel by micromixing/nanoprecipitation in glass capillary devices. Therefore, this review is divided into three main sections in which we discuss the formation of microspheres from single emulsion droplets, microcapsules and polymersomes from higher order emulsion droplets, and nanoparticles from nanosuspensions in a microfluidic channel. Finally, we compare the drug release from these different particles, focusing mainly on those formed from sensitive or supramolecular networks. Marek Brzeziński graduated with a Master's degree in chemistry from Łódź University of Technology in 2008. He obtained a PhD degree in 2014 at the Centre of Molecular and Macromolecular Studies in Łódź, investigating novel properties of PLA-based materials. He was a Humboldt Fellow at Freie Universität Berlin and Helmholtz-Zentrum Berlin for Materials and Energy, working on a project involving the use of microfluidics to design supramolecular capsules for drug delivery. He is now an assistant professor at the Centre of Molecular and Macromolecular Studies in Łódź and his current research interests include functional polymer design and microparticles and nanoparticles for biomedical applications. Marta Socka graduated with a Master's degree in chemistry from the University of Łódź in 2006. She obtained a PhD degree in 2016 at the Centre of Molecular and Macromolecular Studies in Łódź, studying novel processes of the (co)polymerization of cyclic aliphatic carbonates. Her current research interests include the synthesis and characterization of novel polymeric materials, especially aliphatic polyesters and polycarbonate materials for medical applications. Bartłomiej Kost is doing his PhD at the Centre of Molecular and Macromolecular Studies, Polish Academy of Science, under the supervision of Professor Tadeusz Biela and PhD Marek Brzeziński. He received his MSc degree in Cosmetic Technology at the University of Technology of Łódź in 2017.His current studies mainly focus on the supramolecular chemistry of polymers and nano/microparticle preparation.with size even less than 100 nm which can transport their payloads into the cell's interior.

No abstract

Cyclodextrins (CD) are a group of cyclic oligosaccharides with a cavity/specific structure that enables to form inclusion complexes (IC) with a variety of molecules through non-covalent host-guest interactions. By an elegant combination of CD with biocompatible, synthetic and natural polymers, different types of universal drug delivery systems with dynamic/reversible properties have been generated. This review presents the design of nano- and micro-carriers, hydrogels, and fibres based on the polymer/CD supramolecular systems highlighting their possible biomedical applications. Application of the most prominent hydrophobic aliphatic polyesters that exhibit biodegradability, represented by polylactide and polycaprolactone, is described first. Subsequently, particular attention is focused on materials obtained from hydrophilic polyethylene oxide. Moreover, examples are also presented for grafting of CD on polysaccharides. In summary, we show the application of host-guest interactions in multi-component functional biomaterials for controlled drug delivery.