Nanosensor
[4]: 4–10 In addition to their sensitivity and specificity, nanosensors offer significant advantages in cost and response times, making them suitable for high-throughput applications.
These traditional methods may take days to weeks to obtain results and often require investment in capital costs as well as time for sample preparation.
Potential applications for nanosensors include medicine, detection of contaminants and pathogens, and monitoring manufacturing processes and transportation systems.
[4]: 4–10 By measuring changes in physical properties (volume, concentration, displacement and velocity, gravitational, electrical, and magnetic forces, pressure, or temperature) nanosensors may be able to distinguish between and recognize certain cells at the molecular level in order to deliver medicine or monitor development to specific places in the body.
[11] As an example of classification, nanosensors that use molecularly imprinted polymers (MIP) can be divided into three categories, which are electrochemical, piezoelectric, or spectroscopic sensors.
For example, many chemicals are regulated by the Environmental Protection Agency and require extensive testing to ensure contaminant levels are within the appropriate limits.
There are two main approaches in the manufacturing of nanosensors: top-down methods, which begin with a pattern generated at a larger scale, and then reduced to microscale.
These carved out devices, notably put to use in specific microelectromechanical systems used as microsensors, generally only reach the micro size, but the most recent of these have begun to incorporate nanosized components.
In 2006, researchers in Berlin patented their invention of a novel diagnostic nanosensor fabricated with nanosphere lithography (NSL), which allows precise control oversize and shape of nanoparticles and creates nanoislands.
In recent research, capillary forces were induced by applying five microliters of ethanol and, as result, individual nanoparticles have been merged in a larger islands (i.e. 20 micrometer-sized) particles separated by 10 micrometers on average, while the smaller ones were dissolved and absorbed.
Other projects involve embedding clothing with biometric sensors to relay information regarding the user's health and vitals,[27] which would be useful for monitoring soldiers in combat.
Many different government agencies must work together to allocate budgets and share information and progress in testing; this can be difficult with such large and complex institutions.
In addition, visas and immigration status can become an issue for foreign researchers - as the subject matter is very sensitive, government clearance can sometimes be required.
[28] Finally, there are currently not well defined or clear regulations on nanosensor testing or applications in the sensor industry, which contributes to the difficulty of implementation.
Due to their sensitivity, as well as their tunability and resulting binding selectivity, nanosensors are very effective and can be designed for a wide variety of environmental applications.
[30] The "electronic nose" was developed in 1988 to determine the quality and freshness of food samples using traditional sensors, but more recently the sensing film has been improved with nanomaterials.
[34] In a similar fashion, Flood et al. have shown that supramolecular host–guest chemistry offers quantitative sensing using Raman scattered light[35] as well as SERS.
These take advantage of the localized surface plasmon resonance (LSPR) that arises at the nanoscale, which results in wavelength specific absorption.
This is difficult to fully address because nanoparticle toxicity depends heavily on the type, size, and dosage of the particle as well as environmental variables including pH, temperature, and humidity.
[40] Nanosensors possess great potential for diagnostic medicine, enabling early identification of disease without reliance on observable symptoms.
The intracellular implementation of nanosensor synthesized with biodegradable polymers induces signals that enable real-time monitoring and thus paves way for advancement in drug delivery and treatment.
In particular, they have been investigating the particular benefits of zinc sulfide quantum dots which, though they are not quite as fluorescent as cadmium selenide, can be augmented with other metals including manganese and various lanthanide elements.
The nanowires are sensitive to detect trace biomarkers that diffuse into the IV line through blood which can monitor kidney or organ failure.
Similarly to those used to measure atmospheric pollutants, gold-particle based nanosensors are used to give an early diagnosis to several types of cancer by detecting volatile organic compounds (VOCs) in breath, as tumor growth is associated with peroxidation of the cell membrane.
In the field of biotechnology, molecularly imprinted polymers (MIP) are synthesized receptors that have shown promising, cost-effective alternatives to natural antibodies in that they are engineered to have high selectivity and affinity.
It is crucial to build an efficient nanonetwork so that it can be applied in fields such as medical implants, body area networks (BAN), internet of nano things (IoNT), drug delivery and more.
[48] Existing challenges with the aforementioned applications include biocompatibility of the nano implants, physical limitations leading to lack of power and memory storage, and bio compatibility of the transmitter and receiver design of IoBNT.
The nanonetwork concept has numerous areas for improvements: these include developing nanomachines, protocol stack issues, power provisioning techniques, and more.
[51] Additionally, there can be a high cost of raw materials such as silicon, nanowires, and carbon nanotubes, which prevent commercialization and manufacturing of nanosensors requiring scale-up for implementation.
[26] There is also a high degree of precision needed to reproducibly manufacture nanosensors, due to their small size and sensitivity to different synthesis techniques, which creates additional technical challenges to be overcome.
