Note: All electrochemical nano biosensors that have a molecular base depend on a very specific system to detect or track their target molecule. The importance of an electrochemical nanobiosensor is to provide a suitable support for connecting the target molecule to the probe and creating an electrical signal that can be measured and read.In the building of electrochemical biosensors, the minimum parts that are used in a biosensor are: molecular recognition layer and signal transducer which can be connected to a measuring device (device readout) of these signals. DNA is usually a suitable tool as a biosensor because the base pairing reaction between complementary sequences is both specific and stable. In this case, single-stranded probe DNA is immobilized on the detection layer, and then the target DNA reacts with the probe on the surface by pairing. The repetitiveness and unity of DNA structures makes their accumulation on the surface very specific. It is on  this surface that the target DNA is taken and the signal is created. Therefore, it is important to immobilize the nucleic acid of the probe while  maintaining its initial adhesion strength to detect the target DNA. But how this  diagnostic process is measured depends on the method of signal transduction, which may  be optical, mechanical, or electrochemical. Optical bisensors that work based on fluorescence light have some characteristics. These types of biosensors are sensitive to molecules per square centimeter. They consist of 7 rows, so that their detection limit  is almost made of thousands of probes.
Note: In nanotechnology, from modern techniques of molecular simulation to a general framework for the interpretation of AFM images, especially  the analysis of atomic mechanisms that determine the force changes that the microscope measures and the contrast of the image, producesThe recent advent of high-resolution imaging and force spectroscopy using atomic force microscopy (AFM) in organic and inorganic solutions opens the way to imaging a wide variety of surfaces and their solvent structure.  However, to take full advantage of the high resolution and provide significant new analytical capability, a detailed understanding of the background contrast mechanisms that lead to atomic and molecular resolution is critical.  Without a theory that connects the measured force to atomic models of the surface and tip of the microscope, the information that can be distilled from these measurements is limited. Molecular dynamics simulations show that the forces acting on the microscope tip result from the direct interaction between a tip and a surface and are entirely due to the structure of water around the tip and surface.  The observed force depends on a tip structure, and the balance is between the mainly repulsive potential energy changes as the tip approaches the surface and the entropic increase, which is sterically prevented from occupying sites near the tip and the water surface.  Understanding the interplay of these various components that contribute to the force of microscopy measurements is critical to the interpretation of high-resolution images of solution interfaces.
Note: The division is based on the wavelength of the output beam and the wavelength of the output beam of the wide range nano laser. According to this and the wavelength, the types of nano lasers include infrared, visible and ultraviolet lasers, for example, the nano laser  produces a beam with a wavelength of about 858.32 X-rays, the wavelength of a solid nano laser is between 9.6 and 10.6 It is a micrometer. This is because the wavelength of liquid lasers are in the infrared and ultraviolet regions, respectively.Nano lasers work on length scales 1000 times smaller than the thickness of a human hair. The lifetime of the light captured in such small dimensions is so short that the light wave has only a few tens or hundreds of times to move up and down. Nanolasers  open new perspectives for on-chip coherent light sources such as lasers that are extremely small and ultrafast. The performance of nano lasers is based on fast conducting nanoparticles such as silver arranged in a periodic array. Unlike conventional lasers, where laser signal feedback is provided by conventional mirrors, nanolasers use radiative coupling between fast conducting nanoparticles such as silver. These 100 nm particles act as small antennas.To produce high-intensity laser light, the distance between the particles is matched to the laser wavelength so that all the particles in the array are irradiated in unison. Fluorescent organic molecules are used to provide the input energy (gain) required for nano lasers.