Application of nano-sensor technology in packaging and printing (1)

[Abstract] Nanomicrosensors are high-tech infiltrated by many disciplines and have important application value in the field of packaging and printing. This article separately describes the overview of nanosensors related to packaging, types, sensing principles, constituent materials, and the structure and application range of sensors, revealing the latest sensor technologies in the world and trends in development research.

[Key words] Nanosensors Types and characteristics Sensing materials Packaging applications

A nano-micro sensor overview

1. Sensor concept

The sensor is a device for information acquisition and processing. The sensory organs of the human body is a perfect sensing system. The physical information and physical quantities such as light, sound, temperature, and pressure of the outside world are sensed by the eyes, ears, and the skin. The physical sensing is used, and the odor and taste are sensed through the nose and tongue. The chemical stimuli used to sense the composition of matter is a chemical sensor. It is a miniaturized device that can specifically and reversibly respond to a certain chemical composition and can produce a ratio proportional to the concentration of the chemical composition. The measurable signal. The biosensor is a kind of special chemical sensor. It is a biologically active unit (eg, enzyme, antibody, nucleic acid, cell, etc.) as a biosensing element and has a highly selective detector for the target analyte. It captures the reaction between the target and the sensitive motif through various physical and chemical signal converters, and then expresses the degree of the reaction using discrete or continuous electrical signals, thereby obtaining the concentration of the analyte.

The sensor responds to the existence of something we want to test in an identifiable way. There are sensors for measuring temperature, water, light, sound, electricity, and special molecules as well as special biological targets such as bacteria, toxins, explosives, or DNA. However, the sensor used to test the molecular structure of the molecule may be the most valuable and important. A car must have more than 30 sensors, satellite rockets and missiles have as many as thousands of sensors, and the application of sensors of various angles, speeds, temperatures, pressures, flows, voltages, and currents in industrial production also follows the level of automation. Increasing and growing. Such as the temperature sensors in microwave ovens, temperature sensors in air conditioners, gas fire alarm systems, etc., these increasing demands have greatly promoted the development of sensors. At the same time, people also hope that the sensors not only run stably and measure accurately, but also be portable and easy to operate. As an important device in the field of information technology, sensors have been widely recognized and valued by the scientific and technological communities at home and abroad.

2. Nanosensors

Sensor technology is critical to the monitoring and control of the environment. The concept of the sensor is nothing new. In the early 19th century, Humphrey David developed a miner lamp that is sensitive to the presence of gas in the coal mine, but nanotechnology will make the whole new type of super-sensitive The sensor becomes possible. We have manufactured nanosensors and their general properties. Nanosensors are more novel than you can think of. Perhaps the first major commercial application technology.

A sensor is a device that can indicate the presence of a particular molecule or biological tissue and how much is present. Sensors already exist in our entire society, but the best sensors will be made by nanostructures, and, at first sight, it will revolutionize the medical and food packaging industry. Micro-sensors are one of the three key technologies of micro-mechanics. Micro-sensors include sensors that sense and detect mechanical quantities, magnetic quantities, thermal quantities, chemical quantities, and biomass. Each type of sensor can be divided into many types.

Microsensors are one of the most promising applications for ultrafine particles. Generally, ultrafine particles (metals) are black, have the characteristics of absorbing infrared rays, and have large surface area, high surface activity, and sensitivity to the surrounding environment (temperature, atmosphere, light, humidity, etc.), so as early as the 1980s, Matsushita Electric Industrial ( Abe et al. developed the tin oxide ultrafine particle sensor, and then developed an optical sensor. However, the application research of nano-ultra-fine particle sensors is still in its infancy, but it is expected that ultra-small, low-energy, multi-function sensors with high sensitivity can be made using nano-ultra large particles.

Second, the nature of nano-sensors

Indeed, examples of nanoscience and nanotechnology and nanoscale sensors are very common in the biological field. Sensors are crucial for information exchange, and information exchange with other organisms is one of the main features of life. Signals come from a variety of different ways including molecules, sounds, smells and touches. They can also appear as electromagnetic waves, such as heat and light. The ability to detect these signals is both desirable, as is also the case in aromatic perfumes, such as the detection of chemical thiols, which are unpleasant sulfur-containing substances that are added to natural gas delivered to homes.

For some animals, especially dogs, the sensitive nanosensors in the nasal sac are critical to their survival, and they are also critical in some ways to help humans. The basic principle behind the sexual attractant (phenomenon) that is hidden behind the dog's odor-sensitive or in most insect worlds is molecular recognition. The auxiliary shape in the sensory tissue of the dog's nose or in the susceptor of the insect can identify the shape of the signal molecules, as well as the special distribution of the charge on their surface.

In addition to chemical judgment, other features of the biological world rely on sensors. Many flowers and leaves are attracted by the sun, and the sun is their source of energy. Special molecular sensors within the tissues of leaves and flowers respond to the appearance of the sun. These sensors send a signal to the molecular motors of the leaves or flowers to turn them in a special direction so as to face the sun and gain more energy. Animals have ears to feel the sound, while fish have sidelines to sense changes in sound and pressure. All of these are induction mechanisms, and they are important to life.

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