Nanosensors in a nutshell

Imagine being on the treadmill, and you’re feeling great. You’re on top of the world. You are in shape, so your breathing is steady, and you are in fantastic health, but then, the phone rings. You waltz over to the phone. It’s your doctor. She says there’s a significant possibility that you will have an asthma attack within twenty-one days. You wonder why your doctor never told you that she was psychic, but then you remember the biosensor that was put into you a few months prior. That is the miracle of nanotechnology.

Nanotechnology broadly includes all technologies that handle nanoscale materials, and in a narrow sense, technologies that handle unique phenomena that arise in the 10-to-100 nanometer (nm) size range. Even though this nano-sized device is too small for even a microscope to see; it just predicted an event that you had no physical symptoms for yet. It did this by sensing an increase in your nitric oxide levels. Nanosensors are useful because they can detect information with greater sensitivity and specificity than ever before. Nanosensors have only begun in their possibilities of exposing illnesses and other medical conditions, such as cancer and seizures.

What is nano?

To understand nanotechnology, you must know what nano is. Nano describes the size of a particle. A centimeter is one hundred equal pieces of one meter. A millimeter is ten even pieces of a centimeter. One-millionth of a millimeter is a nanometer. For a perspective on how small nanosensors are; one strand of hair is 100,000 nm wide, and a single red blood cell is 10,000 nm wide. Red blood cells are still too big to be considered nano, although they are made up of nanomaterials. If you were nanoscale (1,000 times smaller than a red blood cell), you would be small enough to hold a simple cold virus in your hands.

Types of nanosensors

A sensor is an instrument that responds to a physical stimulus such as heat, light, sound, pressure, magnetism, or motion. It collects and measures data regarding some property of a phenomenon, object, or material. Nanosensors provide information that must be processed and analyzed. Your fingers don’t tell you what you are feeling, but they send the brain information so that it can process it and make a determination. Different sensors have different purposes and intentional placements. There are optical, chemical, physical, and biological nanosensors.

Chemical nanosensors

Chemical sensors usually contain two primary components: a receptor and a transducer. Transducers produce an electrical signal like a human nerve. These collect information from molecules.

Physical nanosensors

The physical nanosensors sense an environment’s physical change such as force, acceleration, flow rate, mass, volume, density, and pressure. Examples of physical sensors include automatic doors, airbags, motion detectors, etc.

Optical nanosensors

Proximity sensors are designed for use in detecting the presence of an object or motion detection in various industrial, mobile, electronic appliance and retail automation. Examples of proximity sensor usage include the detection of an out-of-paper status of a printer or a mobile phone screen that dims to save battery. Ambient light sensors provide precise light direction for a wide range of ambient brightness and are commonly used in LCD backlight control in mobile phones.

Biological nanosensors

Biologic sensors are chemical sensors in which the recognition system utilizes biochemical mechanism. They can sense cancerous changes in living cells as well as asthma. The devices are manufactured with synthetic polymers, called dendrimers, that are made layer by layer into spheres with diameters of less than 5 nm.

How are nanosensors built?

There are different methods for making such tiny machines. (1) Top-down lithography: They are carved out of a larger measure of material to nanometer parts; (2) Molecule self-assembly: Beginning with specific components, molecules are attracted and assemble themselves; and (3) Bottom-up fabrication: adding atoms to atoms, molecules to molecules. “Self-assembly” of atoms and molecules.

Where do nanosensors need improvement?

Challenges include finding ways to mass-produce nanosensors, make nanosensors more reliable, and doing all this inexpensively so that the technology is useful and scalable. Nanosensors are only the beginning and will open all kinds of medical, environmental, and physical doors for scientists to explore. As long as it doesn’t become abused; this information will be a significant step in our future-forward.