Nanoparticles
Nanotechnology is currently revolutionizing the drug industry. The estimated revenue that can be generated by the further development of the nanotech industry is around $380 billion. Current research on nanotechnology is focused on the delivery of drugs into a biological system that, at the moment, has a low efficacy. With what is known as the nanoparticle, nanotechnology can increase the efficacy of drugs.
Nanoparticles (NPs) are self-contained particles that fall within a scale of 100 nm or less. They range from simple cell organelles to complex silica-based ceramics. Each individual particle has advantages and disadvantages that create no clear standard for the pharmaceutical industry to use. However, there are common properties among the forerunners that make them advantageous over traditional drug delivery methods. NPs:
· Are resistant to settling, which means that the drugs will remain in solution and not precipitate
· Have higher saturation solubility, which allows drugs to be taken up faster
· Have rapid dissolution, increasing the drug effect speed
· Have enhanced adhesion, which allows NPs to stick together and clump creating drug reservoirs
· Have concept known as enhanced permeability and retention (EPR) which allows them to target specific cells
· Drug release has degrees of control, which can vary completely from one NP to the next
· Can lower doses, more efficient drug delivery allows a smaller dose to obtain the same effect
Nanoparticles (NPs) are self-contained particles that fall within a scale of 100 nm or less. They range from simple cell organelles to complex silica-based ceramics. Each individual particle has advantages and disadvantages that create no clear standard for the pharmaceutical industry to use. However, there are common properties among the forerunners that make them advantageous over traditional drug delivery methods. NPs:
· Are resistant to settling, which means that the drugs will remain in solution and not precipitate
· Have higher saturation solubility, which allows drugs to be taken up faster
· Have rapid dissolution, increasing the drug effect speed
· Have enhanced adhesion, which allows NPs to stick together and clump creating drug reservoirs
· Have concept known as enhanced permeability and retention (EPR) which allows them to target specific cells
· Drug release has degrees of control, which can vary completely from one NP to the next
· Can lower doses, more efficient drug delivery allows a smaller dose to obtain the same effect
targeting
A crucial factor for nanoparticle success and effective drug delivery is the delivery of the drug exactly where it needs to go; this process is called targeting. If an especially harmful drug misses its target and comes in contact with healthy tissue, a patient could possibly be injured. Targeting can be accomplished in many ways, but the most useful method is to attach ligands —which can range from an antibody to an aptamer — to the surface of the NP. These ligands will be specifically chosen for the target cell. The NP will reach the target cell and the ligands attached to its surface will interact and bind with the receptors of the target cell.
There are two ways to target a cell: actively or passively. The process just described involving the surface ligands is called active targeting, since the NPs actively seeks out the target cell receptors. Due to the feasibility of active targeting, more research is needed. Passive targeting works, as the name suggests, passively. NPs are sent to try to get stuck between the infected tissues, or look for a pH change to indicate when to release the drug. The method is more used but lacks necessary control.
There are two ways to target a cell: actively or passively. The process just described involving the surface ligands is called active targeting, since the NPs actively seeks out the target cell receptors. Due to the feasibility of active targeting, more research is needed. Passive targeting works, as the name suggests, passively. NPs are sent to try to get stuck between the infected tissues, or look for a pH change to indicate when to release the drug. The method is more used but lacks necessary control.
Current research
Because nanoparticles are used within the human body, they are subject to the Food and Drug Administration guidelines and go through rigorous trails before they can be sold in open market. So when nanoparticles are cleared for sale, scientists begin to conduct more research on that nanoparticle.
One of the more important nanoparticles currently undergoing reseach is the mesoporous silica nanoparticle (MSN). Silica is an inorganic compound that is porous and can easily cross-link to drug molecules. MSNs have received a lot of attention because of their ordered structures, large pore size, high surface area, high biocompatibility, variable size, interconnected pores, and more.
Carbon nanotubes (CNT) are also becoming a larger part of biomedical research. With roots in tissue engineering, CNTs have begun to be utilized for drug delivery. Drugs can pass through cell membranes and attach compounds to the surface of the CNT very effectively. The only problem with CNTs is that they can be toxic to cells; the more pure the nanotube, the lower its degree of toxicity, but current methods of industrial production include metallic catalysts, which deposit metallic impurities in the tubes (see "Nanotube and Carbon Fiber Overview" in the Materials Science section of this site for more information).
Research focuses heavily on the delivery of anti-cancer drugs, but there are drugs that can be improved by utilizing nanoparticles. Experimentation was done using nanoparticles to solve some problems experienced by ocular pharmaceuticals. The treatment had problems with eye irritation, poor aqueous stability, and solubility that could be solved with the implementation of nanotechnology.
One of the more important nanoparticles currently undergoing reseach is the mesoporous silica nanoparticle (MSN). Silica is an inorganic compound that is porous and can easily cross-link to drug molecules. MSNs have received a lot of attention because of their ordered structures, large pore size, high surface area, high biocompatibility, variable size, interconnected pores, and more.
Carbon nanotubes (CNT) are also becoming a larger part of biomedical research. With roots in tissue engineering, CNTs have begun to be utilized for drug delivery. Drugs can pass through cell membranes and attach compounds to the surface of the CNT very effectively. The only problem with CNTs is that they can be toxic to cells; the more pure the nanotube, the lower its degree of toxicity, but current methods of industrial production include metallic catalysts, which deposit metallic impurities in the tubes (see "Nanotube and Carbon Fiber Overview" in the Materials Science section of this site for more information).
Research focuses heavily on the delivery of anti-cancer drugs, but there are drugs that can be improved by utilizing nanoparticles. Experimentation was done using nanoparticles to solve some problems experienced by ocular pharmaceuticals. The treatment had problems with eye irritation, poor aqueous stability, and solubility that could be solved with the implementation of nanotechnology.
Conclusions
The versatility of nanotechnology can allow for a new age in pharmaceuticals. With the ability to target specific cells, trigger drug delivery in a controlled manner, lower dosage amounts, control size and shape, and effectively distribute drugs throughout the body, nanoparticles can help save lives and lower risk when treating diseases.
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