The efficiency of the diagnostic platforms utilizing ELISA technique or immunoassays depends highly on incubation times of the recognition elements or signaling molecules and volume of the patient samples. In conventional immunoassays, long incubation times and excess amounts of the recognition and signaling molecules are used. The technology proposed here uses electrokinetic mixing of the reagents involved in a sandwich immunoassay based diagnostic assay in electrode-enabled microwell plates in such a way that the incubation times and volumes can be reduced substantially. The integration of the electrodes at the bottom of the conventional microwell plates ensures that the motions of the liquid flows in the wells can be controlled through the application of high frequency AC current along these electrodes. The strategy to generate chaotic mixing by modification of standard multiwell plates, enables its use in high throughput screening, in contrast to microfluidic channel-based technologies that are difficult to incorporate into conventional plates. An immunoassay for detection of glycated hemoglobin (HbA1c) that can reveal a patient’s average level of blood sugar from the past 2–3 months instead of just measuring the current levels and thereby constitutes a reliable diabetes monitoring platform was chosen as a pilot assay for technology demonstration. The overall incubation time for the assay was reduced by approximately a factor of five when electrokinetic mixing was employed. Furthermore, when the quantity of the reagents was reduced by half, almost no distinguishable signals could be obtained with conventional immunoassay, while electrokinetic mixing still facilitated acquisition of signals while varying concentration of the glycated hemoglobin. There was also a substantial difference in the signal intensities especially for the low concentrations of the HbA1c obtained from electrokinetic mixing assisted and conventional immunoassay when the quantity of the reagents and incubation times were kept constant, which is also an indication of the increase in bioassay efficiency. The electrokinetic mixing technique has the potential to improve the efficiency of immunoassay based diagnostic platforms with reduced assay time and reagent amounts, leading to higher throughput analysis of clinical samples. It may also open new avenues in point of care diagnostic devices, where kinetics and sampling size/volume play a critical role.

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Metallic nanotubes (NTs) have gained much attention in recent years due to their exciting potential to be just as strong or even stronger than their heavier counterparts, nanowires (NWs), with the same outer radius. Unlike NWs, NTs have inner wall diameter and wall thickness parameters that can be engineered to provide advantage in structural materials design. In this work, molecular dynamics is used to quantify the combined effects of NT specific dimensions, outer radius and wall thickness, on the tensile strength of single crystalline tungsten NTs at room temperature. Uniaxial tensile simulations are carried out for three different crystallographic orientations along the NT axis-two known as brittle orientations and one as ductile orientation. For these three orientations, the strength of NTs can be made higher than NWs, for the same outer radius, as the wall thickness decreases. The calculations indicate that even for the brittle orientations, NTs can be engineered to be more ductile by tuning the outer radius and the wall thickness.