Applications of Inorganic Nanomaterials in Biomedicine

Posted by Tylor Keller on April 1st, 2019

Due to their environmental friendliness, low cost, good biocompatibility and low toxicity, inorganic nanomaterials have wide application and good industrialization prospects in the field of medical treatment, such as nano drug carriers, nanomedicine materials, nano biosensors, and micro-intelligent medical devices. Compared with conventional drugs, chemotherapy and radiotherapy, inorganic nanomaterials can be used as drug carriers to achieve targeted drug delivery and controlled drug release. Therefore, inorganic nanomaterials have good application prospects in targeted administration, controlled release and sustained release of drugs, and cancer treatment. This article will introduce the applications of inorganic nanomaterials in the filed of biomedicine.

Targeted delivery of drugs

The development of nanomedicine carriers offers the possibility of targeted delivery of drugs. Nanopharmaceutical carriers have many advantages. They can improve the efficacy of therapeutic methods such as chemical therapy, photodynamic therapy, and photothermal therapy. They can also change the dynamic characteristics of the drugs and their in the living body, for example, they can carry chemical drugs and biological macromolecules across related physiological barriers, and can also be adapted to different administration routes by preparing nanoparticles of different dosage forms. It is also possible to enhance the targeting ability of target cells or specific organelles by modifying related ligands such as hyaluronic acid, folic acid, transferrin, monoclonal antibody, wheat germ agglutinin, polypeptide, Tat peptide, etc. on the surface of the nanoparticle carrier. The ideal nano-drug carrier should have the advantages of simple preparation method, low toxicity, controlled release, long in vivo circulation time and biodegradability. At present, the main nano drug carriers include inorganic nano materials, carbon nano materials, liposomes, polymers, hydrogels and the like.

Bone transplantation

Clinically, autologous bone graft can be used to treat bone defects caused by trauma, infection, tumor, etc.. However, due to the limited source of autologous bone and long operation time, it is easy to cause excessive blood loss and complications in the donor site. When allogeneic bone is used for bone transplantation, it will produce an immune rejection reaction and is easily infected. Artificial bone made of titanium, bioceramic, nano-bone, 3D simulated artificial bone marrow and other nano-materials have similar effects to autologous bone. Nano-hydroxyapatite is similar to the inorganic components in the human body. Nano-hydroxyapatite particles have small size effects, quantum effects and surface effects. The use of nano-hydroxyapatite as dental implant or bone material not only avoids rejection, but also promotes the repair, integration and healing of human bone tissue.

Clinical diagnosis and treatment

Nanomaterials are widely used in clinical diagnosis and treatment, but they are mostly in the experimental stage. Magnetic iron oxide nanoparticles can be used as a contrast agent in tumor diagnosis, producing magnetic resonance molecular images or multimodal tumor molecular images of tumor molecules, and can also be used for separation and enrichment of circulating tumor cells. Magnetic nanoparticles can also be used in biosensors to separate and capture biomolecules from the liquid phase using magnetic phenomena and nanoparticles. Mesoporous silica has the characteristic of specifically recognizing Ramos cells. Cellular fluorescence imaging probes made of mesoporous silica have good photostability, long fluorescence lifetime, and high biocompatibility. Therefore, the laser imaging of Ramos cells using a laser confocal microscope enables detection imaging and early diagnosis of tumor cells. The special structure and properties of fullerene make it widely used in medical fields such as photothermal therapy, radiation chemotherapy, cancer treatment, etc., and can also be used as a contrast agent for magnetic resonance imaging for clinical diagnosis. However, fullerene is insoluble in water and has potential toxicity to organisms, which limits its clinical application. The solubility of fullerenes can be improved by combining hydrophilic molecules containing hydroxyl groups, and hydroxylated fullerenes have no obvious toxicity and can be used as antioxidants. The near-infrared light can activate the nano-materials in the polyhydroxyfullerene, and the photo-heat can be used to locate the tumor cells, thereby avoiding the accumulation of gold nanoparticles and carbon nanotubes in the body, and using the immune stimulation to inhibit the growth and metastasis of the tumor cells, thereby reducing the size of the tumor and ultimately leading to the apoptosis of tumor cell. Therefore, the modification of carbon nanostructures has potential application value in biomedical engineering fields such as imaging, adsorption, and targeted transportation of drugs. Gold nanoparticles have good biocompatibility, and functionalized gold nanoparticles can be used in biomedical fields such as bioanalysis, drug detection, and clinical diagnosis. They can also be used as nano-probes to detect small molecules such as heavy metal ions and melamine and can detect biological macromolecules such as DNA and protein. And they can also be used to accurately locate polysaccharides, nucleic acids and peptides on the surface of cells and inside of cells.