We show that perfect absorption can be achieved in a system comprising a single lossy dielectric layer of thickness much smaller than the incident wavelength on an opaque substrate by utilizing the nontrivial phase shifts at interfaces between lossy media. This design is implemented with an ultra-thin ($k/65) vanadium dioxide (VO 2) layer on sapphire, temperature tuned in the vicinity of the VO 2 insulator-tometal phase transition, leading to 99.75% absorption at k ¼ 11.6 lm. The structural simplicity and large tuning range (from $80% to 0.25% in reflectivity) are promising for thermal emitters, modulators, and bolometers. V

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Glioblastoma multiforme (GBM) is the most common and aggressive type of glial tumor, and despite many recent advances, its prognosis remains dismal. Hence, new therapeutic approaches for successful GBM treatment are urgently required. Magnetic hyperthermia-mediated cancer therapy (MHCT), which is based on heating the tumor tissues using magnetic nanoparticles on exposure to an alternating magnetic field (AMF), has shown promising results in the preclinical studies conducted so far. The aim of this Review is to evaluate the progression of MHCT for GBM treatment and to determine its effectiveness on the treatment either alone or in combination with other adjuvant therapies. The preclinical studies presented MHCT as an effective treatment module for the reduction of tumor cell growth and increase in survival of the tumor models used. Over the years, much research has been done to prove MHCT alone as the missing notch for successful GBM therapy. However, very few combinatorial studies have been reported. Some of the clinical studies carried out so far depicted that MHCT could be applied safely while possessing minimal side effects. Finally, we believe that, in the future, advancements in magnetic nanosystems might contribute toward establishing MHCT as a potential treatment tool for glioma therapy.

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The development of nanostructures with complementary functionalities has emerged as a prerequisite for more efficient preclinical nanoparticle-mediated thermo-therapeutic research. Here, we report the bimodal application of manganese doped-iron oxide nanoclusters for photothermal and magnetic hyperthermia-mediated glioblastoma therapy. Besides the combinatorial effect, we have also explored the comparative effects of the single-mode therapies when seldom used in terms of cell viability, oxidative stress production, reduction in mitochondrial membrane potential, cytoskeletal damage, and morphological alterations. In all aspects, exposure to magnetic hyperthermia was shown to have a higher therapeutic effect than the photothermal therapy when used alone. However, it is ultimately the consequence of bimodal therapy application that results in significant death of rat glioma C6 cells. Excitation of cells with a laser was observed to create oxidative stress in the cellular environment which enhanced the efficiency of magnetic hyperthermia, resulting in a remarkable anticancer effect mediated by ROS-dependent apoptosis via the mitochondrial pathway.

Trapping and manipulation of nano-objects in solution are of great interest and have emerged in a plethora of fields spanning from soft condensed matter to biophysics and medical diagnostics. We report on establishing a nanofluidic system for reliable and contact-free trapping as well as manipulation of charged nano-objects using elastic polydimethylsiloxane (PDMS)-based materials. This trapping principle is based on electrostatic repulsion between charged nanofluidic walls and confined charged objects, called geometry-induced electrostatic (GIE) trapping. With gold nanoparticles as probes, we study the performance of the devices by measuring the stiffness and potential depths of the implemented traps, and compare the results with numerical simulations. When trapping 100 nm particles, we observe potential depths of up to Q ≅24 k B T that provide stable trapping for many days. Taking advantage of the soft material properties of PDMS, we actively tune the trapping strength and potential depth by elastically reducing the device channel height, which boosts the potential depth up to Q ~200 k B T , providing practically permanent contact-free trapping. Due to a high-throughput and low-cost fabrication process, ease of use, and excellent trapping performance, our method provides a reliable platform for research and applications in study and manipulation of single nano-objects in fluids.