by Keyword: Poly(3,4-ethylenedioxythiophene)
Munoz-Galan, H, Molina, BG, Bertran, O, Perez-Madrigal, MM, Aleman, C, (2022). Combining rapid and sustained insulin release from conducting hydrogels for glycemic control br European Polymer Journal 181, 111670
Innovative insulin delivery systems contemplate combining multi-pharmacokinetic profiles for glycemic control. Two device configurations have been designed for the controlled release of insulin using the same chemical compounds. The first insulin delivery system, which displays a rapid release response that, in addition, is enhanced on a short time scale by electrical stimulation, consists on an insulin layer sandwiched between a conducting poly(3,4-ethylenedioxythiophene) (PEDOT) film and a poly-gamma-glutamic acid (gamma-PGA) hydrogel. The second system is constituted by gamma-PGA hydrogel loaded with insulin and PEDOT nanoparticles by in situ gelation. In this case, the insulin release, which only starts after the degradation of the hydrogel over time (i.e. on a long time scale), is slow and sustained. The combination of an on-demand and fast release profile with a sustained and slow profile, which act on different time scales, would result in a very efficient regulation of diabetes therapy in comparison to current systems, allowing to control both fast and sustained glycemic events. Considering that the two systems developed in this work are based on the same chemical components, future work will be focused on the combination of the two kinetic profiles by re-engineering a unique insulin release device using gamma-PGA, PEDOT and insulin.
JTD Keywords: Conducting polymer, Constant, Diabetes, Diabetes-mellitus, Drug-delivery, Electrodes, Electrostimulation, Glucose-responsive hydrogels, Hydrogel, Molecular dynamics, Molecular-dynamics, Nanogels, Nanoparticles, Poly(3,4-ethylenedioxythiophene), Risk
Molina BG, del Valle LJ, Casanovas J, Lanzalaco S, Pérez-Madrigal MM, Turon P, Armelin E, Alemán C, (2021). Plasma-Functionalized Isotactic Polypropylene Assembled with Conducting Polymers for Bacterial Quantification by NADH Sensing Advanced Healthcare Materials 10,
Rapid detection of bacterial presence on implantable medical devices is essential to prevent biofilm formation, which consists of densely packed bacteria colonies able to withstand antibiotic-mediated killing. In this work, a smart approach is presented to integrate electrochemical sensors for detecting bacterial infections in biomedical implants made of isotactic polypropylene (i-PP) using chemical assembly. The electrochemical detection is based on the capacity of conducting polymers (CPs) to detect extracellular nicotinamide adenine dinucleotide (NADH) released from cellular respiration of bacteria, which allows distinguishing prokaryotic from eukaryotic cells. Oxygen plasma-functionalized free-standing i-PP, coated with a layer (≈1.1 µm in thickness) of CP nanoparticles obtained by oxidative polymerization, is used as working electrode for the anodic polymerization of a second CP layer (≈8.2 µm in thickness), which provides very high electrochemical activity and stability. The resulting layered material, i-PP /CP , detects the electro-oxidation of NADH in physiological media with a sensitivity 417 µA cm and a detection limit up to 0.14 × 10 m, which is below the concentration of extracellular NADH found for bacterial cultures of biofilm-positive and biofilm-negative strains. f 2 −2 −3
JTD Keywords: bacteria respiration, bacteria sensors, biomedical implants, flexible sensors, poly(3,4-ethylenedioxythiophene), Bacteria respiration, Bacteria sensors, Biomedical implants, Flexible sensors, Poly(3,4-ethylenedioxythiophene)
Puiggalí-Jou A, Wedepohl S, Theune LE, Alemán C, Calderón M, (2021). Effect of conducting/thermoresponsive polymer ratio on multitasking nanogels Materials Science & Engineering C-Materials For Biological Applications 119,
© 2020 Elsevier B.V. Semi-interpenetrated nanogels (NGs) able to release and sense diclofenac (DIC) have been designed to act as photothermal agents with the possibility to ablate cancer cells using mild-temperatures (<45 °C). Combining mild heat treatments with simultaneous chemotherapy appears as a very promising therapeutic strategy to avoid heat resistance or damaging the surrounding tissues. Particularly, NGs consisted on a poly(N-isopropylacrylamide) (PNIPAM) and dendritic polyglycerol (dPG) mesh containing a semi-interpenetrating network (SIPN) of poly(hydroxymethyl 3,4-ethylenedioxythiophene) (PHMeEDOT). The PHMeEDOT acted as photothermal and conducting agent, while PNIPAM-dPG NG provided thermoresponsivity and acted as stabilizer. We studied how semi-interpenetration modified the physicochemical characteristics of the thermoresponsive SIPN NGs and selected the best condition to generate a multifunctional photothermal agent. The thermoswitchable conductiveness of the multifunctional NGs and the redox activity of DIC could be utilized for its electrochemical detection. Besides, as proof of the therapeutic concept, we investigated the combinatorial effect of photothermal therapy (PTT) and DIC treatment using the HeLa cancer cell line in vitro. Within 15 min NIR irradiation without surpassing 45 °C we were able to kill 95% of the cells, demonstrating the potential of SIPN NGs as drug carriers, sensors and agents for mild PTT.
JTD Keywords: cells, cellulose, conducting polymers, controlled delivery, diclofenac, efficiency, electrochemical oxidation, electrochemical sensors, nanogels, nanoparticles, photothermal therapy, pnipam, poly(3,4-ethylenedioxythiophene), Conducting polymers, Electrochemical sensors, Nanogels, Photothermal therapy