Publications

Background/Objectives: The question addressed in the current work is to develop a simulation of a pharmaceutical process (DNA encapsulation within lipid nanoparticles using a microfluidic micromixer) which will be of utility to the end users (laboratory-scale formulation development). The simulation and the microfluidic approach also address sustainability issues, such as reducing the environmental impact of the process itself, and reducing the need for physical testing. The paper details the implementation and validation, taking into account key performance indicators and control parameters. Methods: The main method applied for simulation development is a novel multi-agent approach to incorporate stochastic probabilistic behavior, combined with theoretical definitions from the process experts and relevant literature, and data/results from laboratory-scale experiments with different parameter configurations. Results: The simulation was implemented as a representation of the real physical process, reproducing the relationships between process parameters (flow rates) and experimental key performance indicators (capsule diameter, poly dispersion index, encapsulation efficiency). The simulation results demonstrated a general agreement with the empirical results and provided useful predictive insights for the laboratory experiments. Conclusions: The simulation has potential as a support tool for laboratory experiments to reduce physical testing and indicate the most promising configurations on which to focus, with potential savings in time, resources and other costs.

JTD Keywords: Calibration, Encapsulation, Lipid nanoparticles, Microfluidics, Micromixer, Multi-agents, Optimization, Process simulation, Sustainability

© 2021 Wiley-VCH GmbH One limitation of wearable electronics, and at the same time a challenge, is the lack of energy storage devices with multiple functionalities produced using clean and environmental-friendly strategies. Here, a multifunctional conductive hydrogel containing poly(3,4-ethylenedioxythiophene) (PEDOT) and alginate is fabricated, to be used as electrodes in supercapacitors, by applying water-mediated self-assembly and polymerization processes at room temperature. The interpenetration of both polymers allows the combination of flexibility and self-healing properties within the same hydrogel together with the intrinsic biocompatibility and sustainability of such materials. Initially, PEDOT:polystyrene sulfonate and alginate aqueous solutions are mixed in two different proportions (1:1 and 1:3) and ionically crosslinked with CaCl2. Subsequently, re-interpenetration of poly(hydroxymethyl-3,4-ethylenedioxythiophene) by anodic polymerization in CaCl2 aqueous solution is achieved. Re-interpenetrated 1:3 PEDOT/alginate hydrogels show excellent capacitance values (35 mF cm−2) and good capacitance retention. In addition, the electrochemical properties are not significantly changed after many cutting/self-healing cycles as observed by cyclic voltammetry. Therefore, this sustainably produced hydrogel shows promising properties for use in wearable energy storage devices.

JTD Keywords: flexibility, pedot:pss-alginate hydrogels, self-healing, sustainability, Electrochemical supercapacitors, Flexibility, Pedot:pss-alginate hydrogels, Self-healing, Sustainability