A Novel Electrochemical Conductive Polymer Interface for Controlled Capture/Release of Biological Entities

Materials platforms that enable controlled isolation and subsequent release of biological entities, such as ctDNA, proteins, extracellular vesicles (EVs) and cells, are in great demand, including in applications in medical diagnostics. In that regard, there is a need for materials that are easily incorporated into simple sampling devices and which allow release of intact captured biological entities and without the need for auxiliary and hence contaminating reagents.<br/>Here, we will discuss two capture/release methodologies based on the use of functionalised and highly porous conducting polymer substrates. First approach involves an electrospun mat, coated with a conducting polymer and decorated with gold particles. Utilizing gold-sulfur covalent bonding, the electrospun substrates may be functionalized with aptamer probes selective to EV surface proteins. We demonstrate that EVs derived from primary human dermal fibroblast (HDFa) and breast cancer (MCF-7) cell lines are selectively captured and efficiently (&gt; 92%) electrochemically released in a short time (&lt; 5 min).[1] The second methodology is based on the use of a functionalized conducting polymer, where a specific moiety on the polymer undergoes oxidation/reduction cycles that control and afford controlled capture/ release of biological entities, including antibodies and MCF-7 cells.<br/>The developed methodologies hold a great promise for applications such as biological filters for capturing and concentrating of rare biomarkers for liquid biopsies.<br/><b>References:</b><br/>[1] Akbarinejad A; Hisey, C.; Brewster, Diane ; Ashraf, J.; Chang, V.; Sabet, S.; Nursalim, Y.; Lucarelli, V.; Blenkiron, C.; Chamley, L.; Barker, D.; Williams, D.; Evans, C.; Travas-Sejdic, J., Novel Electrochemically Switchable, Flexible, Microporous Cloth that Selectively Captures, Releases and Concentrates Intact Extracellular Vesicles, ACS Applied Materials and Interfaces, 2020,12, 35, 39005–39013