Organic electrochemical transistors (OECTs) are excellent candidates for applications in sensing and bioelectronics, because of the ability of conductive polymers, such as poly(3,4-ethylenedioxythiophene): polystyrenesulfonate (PEDOT:PSS) to conduct ions and electrons. An OECT device consists of a PDMS-well, that confines the electrolyte solution, a PEDOT:PSS layer that defines the active length of the channel in contact with the electrolyte and an gate electrode immersed in the solution (Figure 1). The application of a source-drain voltage at the opposite sides of the PEDOT:PSS generates the drain current. The charged nanostructures in solution, upon the application of a positive bias at the gate electrode, enter the PEDOT:PSS polymer, producing a proportional dedoping effect, inducing as consequence the drain current decreases. We apply the OECT as sensor of Lecithin Liposomes with the surface modified with a 20:1 ratio of Lecithin: Chitosan (LC). The size of Liposomes are about 100 nm and the surface charge of +45mV. We studied the sensitivity of OECT to LC Liposomes, which could be also loaded with drugs. well. Liposomes in solution are forced to move toward the PEDOT channel. Results. The OECT is able to detect the presence of Lecithin Liposomes in solution of different size and surface charge. The sensing has been performed with both unloaded liposomes and with the coating functionalized with Chitosan, reaching a sensing effect down to 10-5 mg/ml. Conclusion. OECTs are successfully applied for the sensing of Lecitin: Chitosan liposomes with a high sensitivity. The opportunity to realize OECTs with Liposomes electrolytes, open the way for the development of a low-cost and portable real-time sensor for nano-sized drug delivery systems, able to give important information for the drug dose carried by nanovectors. As perspective, OECTs could be also exploited for a real-time monitoring of drug release from drug-loaded nano-carriers.
Real time sensing of drug-loaded Lecithin Liposomes by Organic Electrochemical Transistors
G Tarabella;N Coppedè;R Mosca;S Iannotta
2012
Abstract
Organic electrochemical transistors (OECTs) are excellent candidates for applications in sensing and bioelectronics, because of the ability of conductive polymers, such as poly(3,4-ethylenedioxythiophene): polystyrenesulfonate (PEDOT:PSS) to conduct ions and electrons. An OECT device consists of a PDMS-well, that confines the electrolyte solution, a PEDOT:PSS layer that defines the active length of the channel in contact with the electrolyte and an gate electrode immersed in the solution (Figure 1). The application of a source-drain voltage at the opposite sides of the PEDOT:PSS generates the drain current. The charged nanostructures in solution, upon the application of a positive bias at the gate electrode, enter the PEDOT:PSS polymer, producing a proportional dedoping effect, inducing as consequence the drain current decreases. We apply the OECT as sensor of Lecithin Liposomes with the surface modified with a 20:1 ratio of Lecithin: Chitosan (LC). The size of Liposomes are about 100 nm and the surface charge of +45mV. We studied the sensitivity of OECT to LC Liposomes, which could be also loaded with drugs. well. Liposomes in solution are forced to move toward the PEDOT channel. Results. The OECT is able to detect the presence of Lecithin Liposomes in solution of different size and surface charge. The sensing has been performed with both unloaded liposomes and with the coating functionalized with Chitosan, reaching a sensing effect down to 10-5 mg/ml. Conclusion. OECTs are successfully applied for the sensing of Lecitin: Chitosan liposomes with a high sensitivity. The opportunity to realize OECTs with Liposomes electrolytes, open the way for the development of a low-cost and portable real-time sensor for nano-sized drug delivery systems, able to give important information for the drug dose carried by nanovectors. As perspective, OECTs could be also exploited for a real-time monitoring of drug release from drug-loaded nano-carriers.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
