Enzyme Reaction in the Pores of CaCO3 Particles upon Ultrasound Disruption of Attached Substrate-Filled Liposomes

Single-step formation of degradable intracellular biomolecule microreactors

Here we present a single-step all-aqueous approach to encapsulate biomolecules such as enzymes and proteins into stable microreactors. Key in this method is the use of spray-drying of the biomolecules of interest in combination with oppositely charged polyelectrolytes and mannitol as the sacrificial template. Remarkably, upon spray-drying in the presence of polyelectrolyte, mannitol crystallization is suppressed and the obtained amorphous mannitol offers enhanced preservation of the biomolecules' activity. Moreover, the use of mannitol allows the formation of nanopores within the microparticles upon rehydration of the microparticles in aqueous medium and subsequent dissolution of the mannitol. The oppositely charged polyelectrolytes provide a polymeric framework which stabilizes the microparticles upon rehydration. The versatility of this approach is demonstrated using horseradish peroxidase as the model enzyme and ovalbumin as the model antigen.

Stimuli-responsive LbL capsules and nanoshells for drug delivery

Review of basic principles and recent developments in the area of stimuli responsive polymeric capsules and nanoshells formed via layer-by-layer (LbL) is presented. The most essential attributes of the LbL approach are multifunctionality and responsiveness to a multitude of stimuli. The stimuli can be logically divided into three categories: physical (light, electric, magnetic, ultrasound, mechanical, and temperature), chemical (pH, ionic strength, solvent, and electrochemical) and biological (enzymes and receptors). Using these stimuli, numerous functionalities of nanoshells have been demonstrated: encapsulation, release including that inside living cells or in tissue, sensors, enzymatic reactions, enhancement of mechanical properties, and fusion. This review describes mechanisms and basic principles of stimuli effects, describes progress in the area, and gives an outlook on emerging trends such as theranostics and nanomedicine.

Anisotropic multicompartment micro- and nano-capsules produced via embedding into biocompatible PLL/HA films

We present a novel strategy to fabricate anisotropic multicompartment Janus capsules by embedding larger containers into a soft poly-L-lysine/hyaluronic acid (PLL/HA) polymeric film, followed by adsorption of smaller containers on top of their unmasked surface. This research is also attractive for developing substrates for cell cultures.