Novel reverse electrodialysis biobattery

Biobatteries offer the potential for a continuous, implantable source of power. A primary area of focus for biobatteries in recent years is the use of glucose oxidase immobilized enzymes. In this reaction the glucose oxidase reduces glucose to gluconic acid (along with a hydrolysis step) where a free electron can be captured. While in theory this enzyme has the potential to produce power for long periods of time inside of the body, in practice the immobilized enzyme breaks down over the course of anywhere from hours to days. Therefore, there is a need to explore other technologies to realize the goal of a long term biobattery. The objective of this research was to use a completely new approach to biobatteries by using Gibbs Free Energy of Mixing between a low concentration and a high concentration stream to generate power. Within the body, the blood in the renal vein is reduced in ions (low concentrations) due to the waste removal function of the kidneys. Thus mixing the renal vein’s blood with blood in another vein can produce power by reverse electrodialysis (RED). The RED-based biobattery has a power density on the same order of magnitude as the best glucose oxidase biobatteries. Furthermore, the RED-based biobattery was operated for several weeks with little loss in power

Reverse electrodialysis systems comprising wafer and applications thereof

In one aspect, reverse electrodialysis systems are described herein having constructions operable to reduce membrane stack resistance, thereby requiring significantly less membrane surface area for meaningful electrical power generation. A reverse electrodialysis system described herein comprises an anode and cathode adjacent to a membrane stack, the membrane stack comprising alternating anion and cation exchange membranes defining diluate and concentrate ionic solution compartments, wherein an ion exchange medium is positioned in a diluate compartment

Hollow fibers for artificial lung applications

Artificial lungs are in use, but difficult issues remain in the field of membrane development related to fouling issues. Currently there are external artificial lungs circulating blood outside the body, taking out the carbon dioxide, and inserting oxygenated blood back into the body. An example of this type of machine is the ExtraCorporeal Membrane Oxygenation (ECMO) machine currently used in hospitals. The ECMO takes over the functions for both the lungs and the heart but is only available for short term use by patients with respiratory failure due to infections (1). The fibers in the machine develop fouling due to the fibers’ small surface areas coupled with their long term exposure to proteins in the blood. These factors continuously decrease the gas transfer abilities of the fibers until the machine is no longer effective at exchanging gases with the blood. The goal of this research is to create a lung that can function within the body until an actual lung becomes available using hollow fiber membranes with proteins attached to prevent fouling. A fouling study was performed on 17.8% polysulfone hollow fiber membranes with polydopamine and peptoid attached. Unmodified, polydopamine modified, and polydopamine and peptoid modified fibers were placed in a diffusion chamber with Bovine Serum Albumin (BSA) flowing on the outside of the fibers and oxygen flowing on the inside. Evapoporometry was run on the fibers to determine the pore size distribution of the fibers before and after the run. The evapoporometry of the fibers shows that the pores for the fibers after 48 hours in the chamber are smaller overall with a few larger pores from oxygen flowrate being too high, tearing the pores. There were also fewer pores overall in the fibers after the run; therefore, the fibers are fouling in the diffusion chamber. The oxygen concentration of the BSA was also measured while the BSA was run outside of the fibers in the chamber. The fibers were considered to be completely fouled when no more oxygen was able to diffuse into the BSA. The fouling was shown to take longer to occur in the protein coated fibers than in the unmodified fibers. Reference: (1) Downs, M. (2014, October 18). Artificial Lung Closer to Clinical Trial. Retrieved from WebMD: http://www.webmd.com/lung/features/ar tificial-lung-closer-to-clinical-trial

Membrane-Based Sorbent for Heavy Metal Sequestration

A process is provided for making membrane-based sorbents with enhanced binding activity that are particularly useful for heavy metal sequestration. The process includes the step of selectively hydrolyzing a polyacetylated membrane in order to deacetylate a surface layer of said membrane and expose free hydroxyl groups. This is followed by the oxidizing of the hydroxyl groups to aldehyde groups. This is then followed by the attaching of a polycarboxylic acid such as a polyamino acid, polyalkenoic acid or polypeptide to the membrane through the aldehyde groups. Preferably, the hydrolyzing step is completed under alkaline conditions and the oxidizing step is completed using an aqueous solution of sodium periodate

Method of Preparing a Composite Polymer and Silica-Based Membrane

A method for preparing a chemically activated or polyamino acid functionalized membrane includes the steps of permeating a silica-based membrane with a solution of silane and a solvent so as to react methoxy groups of the silane with silanol groups of the membrane to incorporate epoxide groups and attaching a polyamino acid to the membrane by reacting a terminal amine group of the polyamino acid with one of the epoxide groups on the membrane

Engineering of extracellular matrix scaffolds via hollow fiber cell culture

Extracellular matrix (ECM) tissue scaffolds are seeing increased use for clinical applications, as they significantly decrease the time course of healing for injured tissues; however, the use of animal-sourced matrix for these scaffolds introduces xenogeneic epitopes into the patient toward which deleterious immune responses are directed, decreasing the effectiveness of the scaffold. ECM scaffolds produced in vitro have potential to minimize the foreign body response, as ECM can be cultured using human cell lines and decellularized to produce an allogeneic scaffold with high biocompatibility. The primary challenge of producing ECM-based therapeutics in vitro is fabricating such material in a manner which approximates the composition and architecture of native matrix while maintaining high yield and ease-of-handling. In previous work, we have demonstrated that sacrificial open-cell foams can be used for the production of ECM scaffolds with properties approximating those of native tissues.1 Herein we demonstrate a novel approach for the production of continuous threads of extracellular matrix by statically culturing ECM-secreting fibroblasts in the lumina of mesoporous hollow fiber membranes (HFMs). This approach exploits the fact that mesoporous HFMs prevent cross-membrane transport of high molecular weight proteins produced by cells in their lumina, while allowing for diffusion of low molecular weight cell medium components. Please click Additional Files below to see the full abstract

Preparing and Regenerating a Composite Polymer and Silica-Based Membrane

A method for preparing and regenerating a chemically activated or polyamino acid functionalized membrane includes the steps of permeating the silica-based membrane with a solution of silane and a solvent so as to react methoxy groups of the silane with silanol groups of the membrane to incorporate epoxide groups and attaching a polyamino acid to the membrane by reacting a terminal amine group of the polyamino acid with one of the epoxide groups on the membrane. The membrane is regenerated after metal entrapment by utilizing helix-coil properties of polyamino acids

Silica-Based Membrane Sorbent for Heavy Metal Sequestration

An apparatus providing for metal ion/nitrate entrapment comprises a chemically activated, microfiltration, composite polymer and silica-based membrane including a polyamino acid attached thereto through reaction of a terminal amine group of the polyamino acid with the membrane. A method for preparing such a chemically activated or polyamino acid functionalized membrane includes the steps of permeating the silica-based membrane with a solution of silane and a solvent so as to react methoxy groups of the silane with silanol groups of the membrane to incorporate epoxide groups and attaching a polyamino acid to the membrane by reacting a terminal amine group of the polyamino acid with one of the epoxide groups on the membrane

Jamie Hestekin: Recubrimientos de nanopartículas celulósicas pulverizables para Covid-19

Descripción de esta presentación: Esta presentación fue hecha por Jamie Hestekin, University of Arkansas. El título de la presentación es: "Recubrimientos de Nanopartículas Celulósicas Pulverizables para Covid-19." Financiado por Ingeniería del NSF / División de Química, Bioingeniería, Medio Ambiente y Sistemas de Transporte. - Descripción de los seminarios web del CIC: Cada mes, el equipo del Centro de Información de COVID (junto con el Northeast Big Data Innovation Hub) reúne a un grupo de investigadores que estudian diversos aspectos de la pandemia actual, para compartir sus investigaciones y responder preguntas de nuestra comunidad. Los eventos muestran los esfuerzos continuos de los científicos en la lucha contra el COVID-19, incluyendo oportunidades de colaboración