Nanotechnology is the direct use of the novel physical, chemical and biological properties of atoms, molecules and substances at the nanometer scale to create materials or products with specific functions. Regarding the application prospects of nanotechnology in animal husbandry and veterinary medicine: It is expected that nanotechnology can be used for single-gene assembly breeding, processing of feed particles, and the development of high-efficiency and low-toxic veterinary drugs.
The nanomedicine we call today uses polymer materials as excipients. The polymer is used to form nanospheres or microcapsules, and the drugs are loaded on the microspheres or in the microcapsules. Its purpose is to effectively control the release of drugs at specific sites with the most suitable release rate and dosage. (1) Hydrophobic polymer dispersion method
(2) Hydrophilic polymer dispersion method
(3) Polymerization method to prepare polymer nanospheres
(4) Preparation of drug-loaded nanospheres by polymer self-assembly method.
(5) Gasification explosion preparation method, etc. If the cost and industrialization problems can be solved, nano-TCM will be applied in the following aspects: (1) Improve or enhance the solubility and bioavailability of traditional Chinese medicine. Before the emergence of nanotechnology, some traditional Chinese medicines had low solubility in water (or other solvents) and could not be made into suitable dosage forms for clinical use. They had to increase the dosage to achieve the effect. However, increasing the dosage may cause corresponding side effects. Side effects, but also a waste of resources. The application of nanotechnology can solve the dissolution problem of traditional Chinese medicine [15], improve the effectiveness of such traditional Chinese medicine preparations, and also make dosage forms more suitable for clinical application. (2) It is convenient to make sustained-release or controlled-release preparations. Some traditional Chinese medicines with short half-lives cannot achieve sustained or controlled release using ordinary means. Similar to Western medicines with short half-lives, frequent administration is required to maintain effective blood drug concentrations in the body. Such traditional Chinese medicines can be easily made into sustained-release or controlled-release preparations using nanotechnology. (3) Targeted drug delivery. According to the different distribution of physiological enzymes and bacteria, cell distribution, network structure, lymph distribution, etc. in different parts of the body, different polymer materials or surface modifications are used to make the required traditional Chinese medicine nanoparticles, which can deliver the traditional Chinese medicine to the designated target. area; magnetic nanoparticles can also be made into magnetic nanoparticles by combining in vivo and in vitro methods to achieve the purpose of targeted drug delivery. (4) Intelligent drug delivery system (feedback-regulated release of drugs). Use nanotechnology to make traditional Chinese medicine into nanoparticles, liposomes, etc., and then carry out appropriate surface modifications, or graft them with polymer materials that are sensitive to changes in certain enzymes, pH values, proteins, etc. in the physiological environment, so that they can be made according to the changes in the physiological environment. Certain change information is used to control the drug release of this type of traditional Chinese medicine preparations. (5) Reduce gastrointestinal irritation of certain traditional Chinese medicines. The gastrointestinal irritation of oral Chinese medicine is related to the particle size and release speed of the drug. For example, drugs that are irritating to the gastrointestinal tract can be made into nanoparticles, nanoemulsions, etc., and then supplemented with appropriate administration forms to reduce the amount of drugs in the stomach. Local "accumulation" release can avoid or reduce gastrointestinal irritation of this type of drug.
At present, the use of gasification explosion preparation technology, also known as solvent-free extraction method, has made a breakthrough in solving the harsh preparation conditions of traditional Chinese medicine such as high temperature and high pressure, making China the first in the world to master gasification pharmaceuticals. The country of technology. This process can not only process plant and animal traditional Chinese medicine into particles below 100nm, but also improve the original active ingredients and pharmacodynamic properties of traditional Chinese medicine in a highly concentrated state. It has remarkable effects in analgesia, beauty and bodybuilding, etc., which brings good development opportunities for the industrialization of nano-TCM. So far, nano-TCM has moved from theory to practice, and there are still many problems that need to be further solved. First, we must consider the necessity and scope of nanotechnology of traditional Chinese medicine. If plant and animal traditional Chinese medicines commonly used in traditional Chinese medicine are processed into particles below 100 nm, the limit is already close to the single molecule level of some macromolecules, which will change the original active ingredients and pharmacodynamic properties of traditional Chinese medicine, thus making it Changes in active ingredients and pharmacodynamic properties. It is generally believed that if the application of nanotechnology in traditional Chinese medicine is limited to certain mineral medicines containing low molecules, inorganic molecules or poorly soluble components, it may have practical value; but if the scope of nanotechnology is extended to a large number of plant or animal traditional Chinese medicines, It is necessary to carefully consider the relationship between the nanoparticle size and the molecular composition and relative molecular mass of the active ingredients contained in relevant traditional Chinese medicine. Otherwise, the effective ingredients of the medicine will be destroyed by obtaining nanoparticles, and the gain will outweigh the loss. Secondly, the feasibility of preparing nano-TCMs should be considered. Nowadays, although the concept of nano-TCM is widely circulated, there are few reports on its preparation method.
There is no big technical problem in the nano-processing of mineral Chinese medicines. Conventional physical and chemical methods for preparing nanomaterials can be used. However, for plant or animal Chinese medicinal materials used in large quantities in Chinese medicine, it has brought about industrialization. Perhaps, the requirements for its detection technology will be higher. In order not to change the active ingredients of traditional plant or animal drugs, they generally cannot be prepared by chemical methods, and it is difficult to process the drugs to a particle size of less than 100nm with the usual mechanical crushing method. Therefore, the gasification preparation method is the current method. Best choice. At the same time, due to the ultra-fine particle size of nano-TCM, its surface effect and quantum effect are significantly enhanced, allowing the active ingredients of the drug to obtain high-energy oxidation or reduction potential. In order to maintain the stability of the drug, attention must be paid to the preservation and storage of nano-drugs.