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Development of nanocomposites as drug delivery vectors is a burgeoning field of research. However, the usage of such newly invented nanomatrices are often limited by the shortcomings associated with the testing of their real-life efficacy. Many drugs fail because a monolayer framework of in vitro cell line screening method does not adequately mimic the in vivo three-dimensional microenvironments. In this direction, the study unveils the development of a continuous flow microreactor wherein the cellulose acetate nanoparticles (CANPs) with varying sizes are prepared before encapsulating them with an anticancer drug - doxorubicin (DOX). Subsequently, an in vitro microfluidic drug delivery model has been introduced in which the HeLa cells specific to cervical cancer is treated with the DOX encapsulated CANPs - DOX@CANPs. Thereafter, the transport of the drugs from the fluidic to cellular environment, their transport inside the cell, and the real-time kinetics of the cancer cell apoptosis have been analyzed systematically to uncover the real-time efficacy and cytotoxic effects of the nanocomposite. Interestingly, experiments reveal, (i) ~89.4% DOX loading on the nanocomposite owing to a facile electrostatic interaction, (ii) a pH-dependent controlled release of drug during the transport with the cancer cells, and (iii) cell apoptosis after the diffused inoculation of the drug. A mathematical model has been developed to emulate the drug transport from the surrounding fluid to the cancer cells. Experiments together with the mathematical model uncover that the kinetics of cancer cell death is limited by the reaction at the cell-nucleus. The microfluidic model has shown significant potential to be translated as a useful tool for the real-time and on-demand in vitro screening of the cancer drugs.

Strategic electron beam (e-beam) irradiation on the surface of an ultrathin (μC cm−2 to 10 000 μC cm−2 to explore the tone reversal behavior of PMMA on the dewetted patterns. Remarkably, at relatively higher e-beam dosing, both PMMA and PS blocks act as negative tones in the exposed zone. In contrast, the chain scission of PMMA in the periphery of the exposed regions due to scattered secondary electrons caused confined dewetting upon solvent annealing. Such occurrences eventually lead to pattern miniaturization an order of magnitude greater than with conventional thermal or solvent vapor annealed dewetting. Selective removal of PMMA blocks of RCP using a suitable solvent provided an additional 50% reduction in the size of the dewetted features.

We study the spin dependent tunneling current properties through oxide multilayers in a magnetic tunnel junction (MTJ). For this purpose, nonequilibrium Green's function approach along-with the density-functional theory have been applied. We employed three structural models of FeO-MgO-FeO multi-layer with three different width of FeO and MgO layer. An atomistic model is considered to describe the effect of oxide multilayers of different heights. Spin dependent study for tunneling reveals that the parallel spin shows higher tunneling current whereas anti-parallel spin conducts very less. Further, the lowest tunneling current is obtained for the case where the FeO and MgO each has 3 atomic layers of height whereas the tunneling current is highest in 4 atomic layers of FeO/1 atomic layers of MgO/4 atomic layers of MgO multilayer structure. Importantly, when the MgO or FeO layers are increased or decreased from this level, the tunneling current decreases significantly. The study reveals that the layer height in the tunneling domain can be important factor for tuning and adjusting tunneling current in the nanoscale regime of oxide layer thickness.

We show that the introduction of slippage has a profound effect on instabilities induced by electric field or contact forces in soft solid elastic films. The critical force required to initiate these instabilities is markedly reduced because of slippage, and is lowest when the slippage arises from an intercalating viscous layer between the elastic film and its rigid substrate. Remarkably, unlike in rigidly bonded elastic films, the length scale of instabilities can be tuned by changing the film thicknesses, material properties of the films, and the strength of the destabilizing force of the bilayers. This feature can be potentially exploited in meso-patterning applications.