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Performance of a sensing device is dependent on its construction material, especially for components that are directly involved in transporting and translating signals across the device. Understanding the morphology and characteristics of the material components is therefore crucial in the development of any sensing device. This work examines the morphological and electrochemical characteristics of reduced graphene oxide interspersed with poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (rGO-PEDOT:PSS) used as a transducer material deposited on a commercially available screen-printed carbon electrode (SPCE). Electron microscopy shows that PEDOT:PSS is interspersed between rGO layers. Raman and XRD analyses suggest that the graphene crystallinity in GO-PEDOT:PSS and rGO-PEDOT:PSS remains intact. Instead, PEDOT:PSS undergoes a change in structure to allow PEDOT to blend into the graphene structure and partake in the π-π interaction with the surface of the rGO layers. Incorporation of PEDOT:PSS also appears to improve the electrochemical behavior of the composite, leading to a higher peak current of 1.184 mA, as measured by cyclic voltammetry, compared to 0.522 mA when rGO is used alone. The rGO-PEDOT:PSS transducing material blended with glucose oxidase was tested for glucose detection. The sensitivity of glucose detection was shown to be 57.3 µA/(mM·cm2) with a detection limit of 86.8 µM.

View references (95) References ( AbstractCancer is a complicated disease for which finding a cure presents challenges. In recent decades, new ways to treat cancer are being sought; one being nanomedicine, which manipulates nanoparticles to target a cancer and release drugs directly to the cancer cells. A number of cancer treatments based on nanomedicine are under way and mostly are in preclinical trials owing to challenges in administration, safety, and effectiveness. One alternative method for drug delivery is the use of photovoltaic nanoparticles, which has the potential to deliver drugs via light activation. The concepts are based on standard photovoltaic cell that holds opposite charges on its surfaces and releases drugs when charge intensity or polarity changes upon photostimulation such as from a laser source or sunlight. This review will cover some recent progress in cancer treatment using nanoparticles, including photovoltaic nanoparticles.

This report describes the development of lab-on-a-chip device designed to measure changes in cellular ion gradients that are induced by changes in gravitational (g) forces. The bioCD presented here detects differential calcium ion concentrations outside of individual cells. The device includes sufficient replicates for statistical analysis of the gradients around multiple single cells and around control wells that are empty or include dead cells. In the data presented, the degree of the cellular response correlates with the magnitude of the g-force applied via rotation of the bioCD. The experiments recorded the longest continuous observation of a cellular response to hypergravity made to date, and they demonstrate the potential utility of this device for assaying the threshold of cells' g-force responses in spaceflight conditions.