Multifunctional nanomaterials have become widely researched in nanomedicine with the goal of developing highly accurate probes for detecting and isolating cancer cells. Of particular interest here are magnetic nanoparticles, which offer the capability of cell isolation from original or enriched samples without the use of centrifugation or filtration. In particular, the combination of fluorescent quantum dots and magnetic nanoparticles into single nanospheres to obtain fluorescent-magnetic bifunctional nanospheres has created the potential for broader applications in biomedicine and in clinical diagnosis. In new work, researchers have now expanded this technique to multiplexed assays. They demonstrated the ability to detect and collect multiple types of cancer cells, such as leukemia cells and prostate cancer cells, from mixed samples within 25 minutes by using a magnet and an ordinary fluorescence microscope.
Research to develop sensors that can rapidly detect biomarkers (associated with certain diseases such as cancer) in whole blood, ideally at the point of care, and when the protein biomarker level in blood is very low (i.e. the disease is in an early stage) is being advanced by nanosensor technology. In a recent development, scientists in Spain have developed a rapid nanochannel-based immunoassay capable of the filtering and subsequent detection of proteins in whole blood without any sample preparation. This is the first time that a simple assay to detect proteins in whole blood using nanochannels has been achieved. This is a simple device and set-up that allows nanochannels to achieve such the double functionality of filtering and detection on the same platform.
Controlled-release drug delivery techniques use various responsive materials and stimuli such as an implanted heat source or electronic chip to trigger the drug release from the implanted reservoir. Among many actively controlled stimuli for pulsatile drug delivery, the electrical signal would be the best source because it is portable and does not need large or special equipment to trigger it. The signal can also be easily and on-demand controllable, and long cycles are possible. Furthermore, when a sensor or microchip system is combined, the feedback and remote control outside the body is possible. Researchers have now developed a new drug delivery device for pulsatile and on-demand drug release based on electrically actuatable nanoporous membranes made of polypyrrole.
Spinal cord injury in humans remains a devastating and incurable disorder. Rapid progress in tissue engineering, especially electrospinning techniques that lead to micro- and nanofibrous flexible tubular scaffolds for nerve cell regeneration, may lead to promising therapies for spinal cord injuries. have now demonstrated the repair of a chronically injured spinal cord by attempting to replace the fluid-filled cyst found in these lesions with a neuroprosthetics conducive to tissue reconstruction and axonal regeneration. They managed, for the first time, to obtain a consistent regeneration of the nervous tissue in chronicized injuries at the spinal cord by using a nanostructured composite scaffold with no cells in it.
One area of nanobiotechnology that will have a massive impact on improving the live of disabled people lies at the interface (literally) between artificial functional materials and living neuronal tissues. Neuroprosthetics is an area of neuroscience that uses artificial microdevices to replace the function of impaired nervous systems or sensory organs. Different biomedical devices implanted in the central nervous system, so-called neural interfaces, already have been developed to control motor disorders or to translate willful brain processes into specific actions by the control of external devices. One are that has been quite challenging is the communication between biological tissues and artificial sensors - something that is key in building artificial retinas, for instance. Researchers in Italy have now reported the functional interfacing of an organic semiconductor with a network of cultured primary neurons.
Imagine intelligent medical implants that can continuously monitor their condition inside the body and autonomously respond to changes such as infection by releasing anti-inflammatory agents. Thanks to nanotechnology, medical research is moving quickly towards this goal. A new study shows that the use of polypyrrole films as electrically controlled drug release devices on implant surfaces can potentially improve bone implants. By electrodepositing antibiotics or anti-inflammatory drugs in a polymer coating on medical devices, researchers demonstrate that such drugs can be released from polypyrrole on demand - by applying a voltage - and control cellular behavior important for orthopedic applications, i.e. inhibit inflammation and kill bacteria.
Chemotherapeutics generally show a delicate balance between maintaining a high enough dose to kill cancer cells while avoiding a dose so high that it causes severe toxic effects. One of the many promises of nanomedicine is a class of nanoscale drug delivery vehicles that can pinpoint cancer cells and deliver their tumor-killing payload right into cancer cells with high efficiency and no side effects. Based on a novel silica 'nanorattle' structure, a research team further extended their work to fabricate 'all-in-one' multifunctional gold nanoshells on silica nanorattles which combine remote-controlled photothermal therapy with chemotherapy. The results indicate that a combination of hyperthermia and chemotherapeutic agents is an encouraging approach to optimizing cancer therapy for the synergistic effects are greater than the two individual treatments alone.
With the advance of nanomedicine, bio-nanotechnology, and molecular biology, researchers require tools that allow them to work on a single cell level. These tools are required to probe individual cells, monitor their processes, and control/alter their functions through nanosurgery procedures and injection of drugs, DNA etc. - all without damaging the cells, of course. Researchers have now developed a multifunctional endoscope-like device, using individual CNTs for prolonged intracellular probing at the single-organelle level, without any recordable disturbance to the metabolism of the cell. These endoscopes can transport attoliter volumes of fluid, record picoampere signals from cells, and can be manipulated magnetically. Furthermore, the tip deflects with submicrometer resolution, and the attachment of gold nanoparticles allows intracellular fingerprinting using surface-enhanced Raman spectroscopy (SERS).