Application of Nanotechnology in agriculture, Health and food preservation with nano biosensors

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Application of Nanotechnology in agriculture, Health and food preservation with nano biosensors

There are many potential applications of biosensors of various types. The main requirements for a biosensor approach to be valuable in terms of research and commercial applications are the identification of a target molecule, availability of a suitable biological recognition element, and the potential for disposable portable detection systems to be preferred to sensitive laboratory-based techniques in some situations. Some examples are given below:

• Glucose monitoring in diabetes patients
• Other medical health related targets
• Environmental applications e.g. the detection of pesticides and river water contaminants such as heavy metal ions
• Remote sensing of airborne bacteria e.g. in counter-bioterrorist activities
• Detection of pathogens
• Determining levels of toxic substances before and after bioremediation
• Detection and determining of organophosphate
• Routine analytical measurement of folic acid, biotin, vitamin B12 and pantothenic acid as an alternative to microbiological assay
• Determination of drug residues in food, such as antibiotics and growth promoters, particularly meat and honey.
• Drug discovery and evaluation of biological activity of new compounds.
• Protein engineering in biosensors
• Detection of toxic metabolites such as mycotoxins

Nanotechnology in Agriculture

1.   Promote Soil Fertility and Balanced Crop Nutrition

2. Effective Weed Control

3.   Enhancing Seed Emergence using carbon nanotubes.

4.   Biosensors to detect nutrients and contaminants

          Protection of the soil health and the environment requires the rapid, sensitive detection of pollutants and pathogens with molecular precision. Soil fertility evaluation is being carried out for the past sixty years with the same set of protocols which may be obsolete for the current production systems and in the context of precision farming approaches. Accurate sensors are needed for in situ detection, as miniaturized portable devices, and as remote sensors, for the real-time monitoring of large areas in the field.

          Soil solution can be allowed to react with nano-sensors that will give accurate measurement of availability of nutrients in the soils. Nanosensors is believed to be used to determine nutrient, moisture and physiological status of plants which assists in taking up appropriate and timely corrective measures. Nano-particles are mini laboratories have the potential to precisely monitor temporal and seasonal changes in the soil-plant system. Nanosensors detect the availability of nutrients and water precisely which is very much essential to achieve the mission of precision agriculture.

Biosensors for seed storage:   Bio-analytical Nano sensors are currently being manufactured. Electronic nose (E-nose) is a device that mimics the operation of human nose in detecting an array of gases. This device contains several gas sensors to detect different types of odors. The main purpose is to identify the odorant, estimate the concentration of the odorant and find characteristic properties of the odor. The main component of e-nose is a gas sensor composed of Nano-particles (zinc oxide nanowires) whose resistance changes when a certain gas passes over it. The change in resistance generates a change in electrical signal that forms the fingerprint for gas detection. The advantage of using nanoparticles is that they have improved uncontaminated surface area for better gas adsorption.

          Seeds during storage emit several volatile aldehydes that determine the degree of ageing. These gases are harmful to even other seeds.  Such volatile aldehydes can be detected and seeds showing signs of deterioration can be separated and invigorated prior to their use. Hence this technique can be employed in storage decision making.

5.   Smart delivery system

           Nanoscale devices are envisioned that would have the capability to detect and treat diseases, nutrient deficiencies or any other maladies in crops long before symptoms were visually exhibited. “Smart Delivery Systems” for agriculture can possess timely controlled, spatially targeted, self-regulated, remotely regulated, pre-programmed, or multi-functional characteristics to avoid biological barriers to successful targeting.

6.   Nanodevices for Identity Preservation (IP) and Tracking

          Identity Preservation (IP) is a system that creates increased value by providing customers with information about practices and activities used to produce a particular crop or other agricultural products. Certifying inspectors can take advantage of IP as a more way of recording, verifying, and certifying agricultural practices. The IP system is highly useful to discriminate organic versus conventional agricultural products.

e. Nanoherbicides for rainfed Agriculture.

In rainfed farming herbicide  encapsulated with nanoparticle can be formulated that remain unaffected and disperse whenever sufficient level of moisture is received. So that the weed seeds which will start with the receipt of rain will get killed by the new herbicides molecule which will released immediately after rain.

Food packaging

A major problem in food science is determining and developing an effective packaging material. Nanoparticles such as titanium dioxide, zinc oxide and magnesium oxide, as well as a combination of them, once functionalized can be efficient in killing micro-organisms and are cheaper and safer to use than metal based nanoparticles. These nanoparticles can improve food packaging in a number of ways.

The most problematic for food packaging engineers is oxygen because it spoils the fat in meat and cheese and turns them pale. Due to the nature of the nanoparticles in Durethan, new plastic material, air cannot penetrate it like other conventional plastics. The embedded particles have a maze like arrangement in the plastic, acting like barriers, which makes it difficult for gases, like oxygen, to pass through the packaging. They actually increase the distance the gas molecules have to travel by causing those molecules to zigzag around the silicate plates in effect increasing the amount of time it will take for the molecules to completely penetrate.

Incorporation of nanoparticles of clay into an ethylene-vinyl alcohol copolymer and into a poly (lactic acid) biopolymer was found to increase barrier properties to oxygen. Polymer-silicate nanocomposites have also been reported to have improved gas barrier properties, mechanical strength, and thermal stability. Nanoclay-nylon coatings and silicon oxide barriers for glass bottles are used to impede gas diffusion.

Polymer Nanocomposites

Nanocomposite technology has been described as the next great frontier of material science in packaging. This technology was developed to improve barrier performance pertaining to gases such as oxygen and carbon dioxide. It also enhances the barrier performance to ultraviolet rays, as well as adding strength, stiffness, dimensional stability, and heat resistance. New plastics created with this technology demonstrate an increased shelf life and are less likely to shatter.

Application of nanotechnology in human health

1.         Biomolecules can be labelled using quantum dots. The intense light of a specific wavelength that these nanocrystals emit enables the path followed by the biomolecules in the cell to be precisely traced.

2.         Antibodies placed on nanowires can be used in a to detect viruses, in a blood sample. For example, the bonding of a single virus particle to an antibody results in a change in the nanowire’s electric conductance. The method is extremely sensitive, which means that an infection can be detected at a very early stage. Detection methods based on nanowires or nanotubes offer the added advantage that it is not necessary to label the sample.

3.         In order to direct the medicines at their target more effectively, drug delivery systems have been developed using nanoparticles. Depending on the type of particle, the active substance can be encapsulated or attached to the surface. This means that even if they dissolve poorly in water, they can be transported in an aqueous solution, such as blood, and are better protected against degradation by enzymes.

4.         Besides acting as a delivery system, in some cases nanoparticles can act as an active substance. Once they have found their way through the bloodstream into a tumour, or have been injected directly into it, metal-containing nanoparticles can be heated using near-infrared radiation or a rapidly oscillating magnetic field so that the tumour cells die.

5.         Nanosuspensions are colloidal dispersions of solid drug particles in a liquid phase with average particle sizes below 1 μm stabilized by the use of surfactants. Drug particle size reduction leads to an increase in surface area and consequently in the rate of dissolution. Nanoparticle-based drug delivery approaches have the potential for rendering hydrophobic agents like curcumin dispersible in aqueous media, thus circumventing the pitfalls of poor solubility.

6.           Artificial joints, such as artificial hips, normally have a life of around ten to fifteen years, after which complications occur, such as wear or implant loosening, and further operations are required. Nanotechnologies could help reduce these problems. The implants, which are usually made of titanium or alloys of cobalt and chromium, can be provided with a thin layer of a nanocrystalline structure, which is harder and smoother and consequently more resistant to wear. Moreover, the layer would ensure that the body better tolerates the implant (better biocompatibility).

7.           Nanomedicine has the potential to enable early detection and prevention, and to essentially improve diagnosis, treatment and follow-up of diseases.  Biological tests measuring the presence or activity of selected substances become quicker, more sensitive and more flexible when certain nano scale particles are put to work as tags and labels.  Nanodevices can make gene sequencing more efficient. Gold nanoparticles tagged with short segments of DNA can be used for detection of genetic sequence in a sample.

8.           Nanotechnology can help to reproduce or to repair damaged tissue. This so called tissue engineering makes use of artificially stimulated cell. It might replace today‟s conventional treatments, e.g. transplantation of organs or artificial implants.  Carbon nanotubes have recently become promising functional materials for the development of advanced biosensors with novel features. These sensors are being used for astrobiology to study origins of life. The technology is also being used to develop sensors for cancer diagnostics. CNT, though inert, can be functionalized at the tip with a probe molecule.