In recent years, growing numbers of nanomaterials and nanotechnology applications have been used as novel imaging, diagnostic, and therapeutic agents in the treatment of cancer and other diseases. The safe and effective development and use of these new nanotechnologies will require coordinated
A study of the effects of biaxial strain on the performance of low-threshold 1.3- mu m In/sub x/Ga/sub 1-x/As/sub y/P/sub 1-y//InP quantum-well lasers is presented. Lasers with lattice-matched, compressive-strained, and tensile-strained quantum-wells were fabricated to compare the effect of strain on various device parameters. Threshold current densities as low as 187 A/cm/sup 2/ for a two-quantum-well device with 0.85% compressive strain were obtained.< >
A novel, three-dimensional 8/spl times/1 micro-Fresnel lens array has been realized by surface micromachining technique; three-dimensional alignment blocks and supporting structures for both the micro-Fresnel lens array and the 8/spl times/1 vertical-cavity surface-emitting laser (VCSEL) array are also realized during the same process. With the help of these three-dimensional structures, self-aligned integration of the micro-Fresnel lens array and the VCSEL array are realized with passive alignment. Individual addressing of the VCSEL/micro-lens element is also successfully demonstrated. With their three-dimensional and array structural characteristics, they are very attractive for free-space optical interconnect and optoelectronic packaging.< >
We discuss the design, integration and testing of thermal components in a microfluidic device designed for on-chip genetic sample preparation. A typical microdevice must perform several operations to be capable of analyzing a sample of body fluid (blood, urine, saliva), extracting DNA from concentrated cells, hybridization, purifying and amplifying DNA, and finally detecting DNA fragments of interest. Reduction of the sample volume down to a few /spl mu/Ls and improvement of the ramp times between temperature steps makes micro-PCR devices desirable. Thermal components such as heaters and resistive thermal devices (RTDs) are fabricated as an integral part of a complete genetic sample preparation micro-system. The ability to precisely control the temperature is a critical component of most microfluidic devices intended for on-chip genetic sample preparation Devices were fabricated and demonstrated a temperature variation of /spl sim/1/spl deg/C over the entire sample volume. The design of a device, including chamber dimensions, and placement of the heating and cooling elements is presented. The results of temperature cycling experiments are shown. We have measured a heating rate of /spl sim/2.4/spl deg/C/s and a cooling rate of /spl sim/2.0/spl deg/C/s for devices tested under active heating/cooling control. A brief overview of relevant microfabrication methods is also presented.
Historically, treatment of patients with cancer using chemotherapeutic agents has been associated with debilitating and systemic toxicities, poor bioavailability, and unfavorable pharmacokinetics.Nanotechnology-based drug delivery systems, on the other hand, can specifically target cancer cells while avoiding their healthy neighbors, avoid rapid clearance from the body, and be administered without toxic solvents.They hold immense potential in addressing all of these issues which has hampered further development of chemotherapeutics.Furthermore, such drug delivery systems will lead to cancer therapeutic modalities which are not only less toxic to the patient but also significantly more efficacious.In addition to established therapeutic modes of action, nanomaterials are opening up entirely new modalities of cancer therapy, such as photodynamic and hyperthermia treatments.Furthermore, nanoparticle carriers are also capable of addressing several drug delivery problems which could not be effectively solved in the past and include overcoming formulation issues, multi-drug-resistance phenomenon and penetrating cellular barriers that may limit device accessibility to intended targets such as the blood-brain-barrier.The challenges in optimizing design of nanoparticles tailored to specific tumor indications still remain; however, it is clear that nanoscale devices carry a significant promise towards new ways of diagnosing and treating cancer.This review focuses on future prospects of using nanotechnology in cancer applications and discusses practices and methodologies used in the development and translation of nanotechnology-based therapeutics.
Despite significant improvements in methodologies behind the development of new anticancer therapies, the path from early-stage drug development through preclinical and clinical development pipeline is still arduous. Further refinement of the current preclinical models and the development of complementing alternative techniques that enable more reliable studies are paramount. The emerging organ-on-a-chip (OoC) technologies are physiological-like organ biomimetic systems built on a microfluidic chip, capable of enabling precise control over various physicochemical and biomechanical parameters and helping recreate the natural physiology and mechanical forces that cells experience in the human body. In oncology research, especially, since cancer has been understood to be a dynamic disease featured by complex interactions between cancer cells and their environment, this technology offers added advantage as it is able to provide a dynamic platform to simulate cancer-on-a-chip emulating the biological context of tumor microenvironment (TME); demonstrating progression to metastases to multiorgans; and helping to unravel complex information that other current in vitro methods are otherwise not able to provide. In this contribution, we provide a biological perspective on the recent advances in the field of OoC models in cancer biology studies from a cancer hallmark perspective. We also discuss current prospects and funding opportunities in this space, as well as a possible future outlook from a biology perspective, including major challenges and new opportunities as a way forward to OoC technologies.
