The main goal of this project is the development of ionphore-embedded membranes with application in bio-analytical devices for electrochemical detection of biomarker electrolytes in sweat but also in other biological media such as serum or cellular cultures.
The focus is the detection of sodium, potassium and chloride ions. In order to achieve this goal, the following objectives are envisaged:
O1: Membrane synthesis and ionophores incorporation.  Bilipidic membranes, hydrogels and liposomes will be synthesized and the incorporation of ionophores investigated.
O2: Immobilization of the ionophore embedded membrane at the electrode surface.  Interaction of the membrane with solid surface may lead to conformational/structural modifications and finding the optimal condition is relevant for achieving the best sensitivity and the lowest detection limit. The sensor performance will be investigated in artificial sweat but also on a biological model designed to detect short and transient responses to the sensor.

Director Proiect: Dr. Anca Aldea (U-1800-055N-8239)
https://www.brainmap.ro/anca-aldea

Mentor Proiect: Prof. Ileana Cornelia Farcasanu (U-1700-033C-8247)
https://www.brainmap.ro/ileana-cornelia-farcasanu

In the second stage of Project PD67 the main objective was to test the devices obtained for the detection and quantification of sodium, potassium and chlorine ions, as well as to determine the characteristics of the sensors. During this phase, the activities of obtaining electrodes from polycaprolactone electrospun polymer fibers and silicon/silicon dioxide waffers metallized with gold, the synthesis of membranes, the incorporation of the ionophore into the synthesized membranes, the immobilization of the membranes with the ionophore incorporated on the surface of the electrodes, continued.
Briefly, polycaprolactone electrospun polymeric fibers were obtained which were coated with a gold layer and electrodes obtained on silicon/silicon dioxide wafers metallized with an intermediate layer of titanium and gold. 3 types of membranes were synthesized: lipid membrane, hydrogel and liposomes. Ionophore incorporation was performed both before and after membrane synthesis. In order to characterize the surfaces obtained, they were analyzed electrochemically (cyclic voltammetry), morphologically (scanning electron microscopy) and structurally (infrared spectroscopy). Sensors obtained by immobilizing membranes with incorporated ionophore on surface were tested for the detection and quantification of sodium, potassium and chlorine ions. Biocompatibility tests were also carried out by using them as a substrate for the proliferation of cell cultures.
As a result of these activities, a 100% fulfillment of objective 1 (O1: Synthesis of the membrane and incorporation of ionophores) and 75% of objective 2 (O2: Immobilization of the membrane with ionophore embedded on the electrode surface) was achieved. Bilipid membranes, hydrogels and liposomes were synthesized and the ionophore incorporation method was optimized, gold surfaces modified with different membranes and ionophores were obtained and characterized, the membrane immobilization method on the electrode surface was optimized and the sensors were tested in order to establish their response to specific  ions of the incorporated ionophores.

Anca ALDEA (DIBLĂ)

National Institute of Materials Physics

Laboratory of Multifunctional Materials and Structures

405A Atomistilor Street

077125, Magurele, Romania

E-mail: anca.aldea@infim.ro

Mobile: +40735157040