What Developments In Nanotechnology Are Currently Being Made For Medical Applications?
Executive Summary
Nanotechnology refers to methods and techniques that can be used to manipulate matter on a molecular level. The use of nanotechnologies in medicine referred to as nanomedicine has many potentials that can be used in several areas, including cardiac regeneration valves, implants, and dental prosthesis. For example, there have been recent developments in drug delivery using nanoparticles, whose minuscule size enables easy penetration. New imaging and diagnostic techniques have been developed using nanotechnology. The miniaturized nature of nano-devices makes them suitable for tracking and identifying pathogens. However, there are also questions raised on the toxicity and privacy when it comes to the use of nanoparticles as these instruments can alter unique characteristics. Extensive research should be conducted on the toxicity and dangers of nanomaterials in the human body to prevent unforeseen harm.
Table of Contents
Introduction
Nanotechnology is an expression by which matter on a minuscule scale can be manipulated. The term nanotechnology is credited to Nobel prize winner R. Feynman (1959). Feynman visualized the possibility of managing matter on a small scale to design tools on a molecular level. Nanotechnologies include methods and techniques that can be used to manipulate substances on a molecular scale. Nanoparticles range in size from 100 to 1 nanometer. Nanotechnology, still at its infancy, warrants intensive research for it to be utilized in the future. In medicine, their potential use in monitoring an organism in a non-invasive manner has drawn criticisms and concerns regarding toxicity. Despite the growing concerns on nanotechnologies some of them are already utilized in areas such as cardiac valves, implants, and dental prostheses. Nanotechnologies offer great potential in science and technology that can be explored and engineered to develop more effective therapies. The unclear and uncertain possibilities of nanotechnology warrant increased research and investment when it comes to safety and exposure, especially in a workplace setting.
Applications of Nanotechnology in Medicine
The application of nanotechnology for health purposes, such as specific diagnostic and therapeutic uses, is defined as nanomedicine. Nanomedicine aims at revolutionizing the processes of control, repair, and monitoring of the human body on an atomic level using designed structures. Such technologies have the potential of developing and increasing the levels of accuracy of drug delivery in patients; with such advancements, drugs will be able to reach the intended target with high levels of efficiency. Some of the nanocarriers can easily be modified to avoid the immune-defences of the human body and are projected to revolutionize early identification of diseases, making it easier to monitor its progress in real-time.
Nanomedicine, an emerging technology with limitless potential though vital for the future of medicine, is still at its experimental stage, and rigorous testing is recommended to establish proper safety measures. The development of nanoparticles that can carry and deliver drugs to target sites in the body promises much potential in the safe and effective delivery of medicines and treatment of several ailments. Even though it is difficult to develop to reproduce exterior surfaces that allow nanoparticles to undergo regular interactions, scientists have recently come up with new designs to bypass such challenges (Farokhzad, 2015). For example, nanoparticles coated with platelets’ membranes are undetectable by the immune system and possess platelet-like properties that allow them to bind along with desired cells and tissues. Platelets are usually deployed to injured or damaged blood vessels that release collagen from their sub-endothelial layers (Farokhzad, 2015). Collagen proteins often bind with platelets releasing several blood clotting factors that promote the formation of a platelet plug. Several conditions, including cancer and trauma, can lead to vascular damage promoting the formation of platelets clots around the region, making the use of nano-engineered platelet-like medicines effective in drug targeting.
Recent developments have opened up possibilities on the use of nanotechnology on regenerative medicines and methods, including the fields of vascularization, bone regeneration, and neural tissue engineering. Newly developed nanoparticles can mimic the natural micro-environments of cells inducing differentiation, adhesion, proliferation, and cohesion in the process (Hastar et al., 2017). Nanomaterials can be engineered with desirable properties that can be used to control chemical, biological, structural, and mechanical micro-environment for successful cell regeneration and delivery. By decreasing the size of the particles to nanoscale, physiological areas that were previously inaccessible to conventional molecules can be reached. For example, the blood and brain testis barrier is particularly challenging to bypass. Therefore, the delivery of treatment to these critical areas often proves a challenge. However, small-sized nanoparticles can penetrate through tight endothelial junctions, that are usually impermeable to other forms of treatment. Surgical treatments, such as discectomy and fusion, when treating degenerative diseases, can lead to loss of mobility, post-discectomy spondylosis, and disc herniation. Inconsistent outcomes and complications have promoted the need to use novel nano-based technology, such as tissue engineering for intervertebral disc (I.V.D.) regeneration. These therapies can generate mesenchymal stem cells that can undergo differentiation into nucleus pulposus-like phenotypes.
Nanotechnology can be used in imaging and diagnostics, particularly when looking for cancer-causing genetic mutations. There is increasing use of nanotechnology on a molecular level of identification in the form of miniaturized implant devices in the body. Such devices provide a significant advantage when it comes to locating pathogens in an organism. The machines are capable of relaying images on the affected areas and conducted target therapy (Radwan, 2018). The binding ligand properties of nanoparticles to specific genetic mutations supports detailed imaging at the cellular level. Nanoparticles offer modifiable qualities that can be used to generate multi-modal and multi-functional imaging vehicles with modifiable features, promoting the integration of contrast materials, ligands, and functional groups. Adding a contrast agent to the nanomaterials enables for visualization of tumour cells that express specific mutations.
The technique may allow for early identification of metastatic potential of a malignancy, coupled nano-based drug delivery techniques. Chemotherapy can be administered even before the onset of clinical symptoms reducing the risk of morbidity. Also using fluorescent probes, imaging and nanotechnology can assist in the assessment of cancer treatment therapies. Nanotechnologies can also be used to repair cartilage defects, especially in athletes as adult cartilage tissues lack the proper repair response (Smith et al., 2018). Nanofibrous scaffolds containing polycarbonate and gelatin can enhance articular cartilage repair and bone regeneration. Also, nanotechnology can be used to facilitate spinal fusion, eliminate costs and potential complications associated with recombinant human bone morphogenetic protein (rhBMP) (Chandarana, Curtis, and Hoskins, 2018). Nanoparticles such as titanium oxide and zirconia when used in titanium spinal implants have shown potential in promoting increased bone formation and decreased re-absorption.
Moreover, cervical cages can be enhanced using silicon nitride nanoparticles that have multiple biomechanical advantages. In regards to therapeutic use, nanoparticles can be used to carry the active agents to the affected cells with the aid of nanocapsules avoiding severe side effects, unlike the case of anticancer drugs. Efforts are underway to design implants that can boost healthy bone growth while inhibiting cancer growth (Walmsley et al., 2015). Currently, nano-selenium implants have been found to inhibit the growth of malignant osteoblasts and promote healthy bone functions at implant-tissue interference. Selenium nanoparticles were discovered to increase bone adhesion, bone proliferation, calcium deposition, and alkaline phosphate activity.
There have been recent developments in the use of nanotechnologies in treating wound dressings and skin regeneration. Research shows that nanotechnology can be useful in treating problematic wounds and ensure wound closure. The two main categories of impaired injuries include ulcers and burn scars. Unlike traditional wound dressing, tissue-engineered nanotechnology can be used to cover wounds and promote regeneration of skin cells. Some of the complexities of tissue-engineering include the amount of time taken up and the extensive in vitro cell culturing process required (Chandarana, Curtis, and Hoskins, 2018). However, nanotechnology significantly reduces the cell culturing time as nanostructured T.E. scaffolds are effective in targeting and delivering required components. Nanotechnology-based wound dressings have several features that can be tailored to address specific wounds. Such dressings can be customized to contain anti-inflammatory, antibacterial drugs to treat a particulate wound. For example, in the case of pathogenic bacterial infection, antibacterial materials can be added into the nanocarriers to target the infection-causing microbes.
Polymeric nano-particles posses several manipulative qualities that make them excellent materials for absorption in the body. The ease of delivery also promotes their use as minimally invasive methods can be used to get them into the systemic circulation. Intravenous injections are the most common methods of administration; however, oral, dermal, and mucosal administration are also available (Fontaine, Rannard, and Stone, 2014). Overall, polymer-based nanoparticles are more cost-effective and more comfortable to manufacture and scale-up compared to liposomes. Damaged blood vessels either through ischaemia or atherosclerotic plaques can be substituted with expanded polytetrafluoroethylene (ePTFE) grafts to re-establish regular blood flow (Nikalje, 2015). Adding nanoparticles into the ePTFE surface can promote stability and biocompatibility of the graft fibroblasts with minimal cytotoxicity.
Electro-spinning is also a technique that is becoming increasingly popular when it comes to producing microstructured scaffolds that have the correct spatial orientation of fibres. Structures of wounds dressed using the electrospinning technique promote the rapid, layer-to-layer build up of tissues in deep wounds supporting the proliferation and distribution of new cells throughout the scaffold. Also, a nanofiber T.E. structure has several suitable properties for wound dressing, such as mechanical stability, allowances for gas exchange, and the ability to absorb wound discharges (Smith et al., 2018). Nanotechnology can also be used in cardiac tissue regeneration, significantly contributing to the development of functional heart tissue engineering. The complexities involved in the culturing of cardiomyocytes, mainly when cultures of cardiac cells are required presents a significant challenge in cardiac tissue regeneration. Recent advancements in nanotechnology have enabled the development of nanostructures with the ability to control cell behaviour (Fontaine, Rannard, and Stone, 2014). The surface features and dimensions of such structures are essential in regulating cell adhesion and regeneration, in addition to gene expression, differentiation, and proliferation. Biomimetic cardiac extracellular matrices (E.C.M.) can replicate natural nanophotography of cardiac tissues, producing better cell connections and distinction.
Conclusion
There are several significant uses of nanotechnologies in the field of medicine, including bio-imaging and drug delivery. The minuscule size of nanoparticles, particularly those coated with platelet like properties, can penetrate several layers can effectively deliver the needed medicines. Miniaturized nano-devices can be implanted into the body to locate pathogens. Some of the binding properties of these nanoparticles make them suitable for detailed imaging at the cellular level. Recent developments in cell regeneration have led to the incorporation of nanotechnology in wound dressing, as it can significantly reduce cell culturing time and improve stability of the wound
Recommendations
There are significant ethical challenges facing nanotechnology since it is a relatively new and uncertain form of technology, and as such, some of the hazardous effects are yet to be fully understood. This can be explained by differences in properties such as toxicity of material in its natural state compared to its nano level. The difference in toxicity in the two-state has raised several issues when it comes to inhalation or ingestion of nanomaterials, especially by individuals who are unaware of such side effects (Spagnolo and Daloiso, 2009). In medicine, the use of nanotechnology in imaging has raised concerns on autonomy and privacy.
The other particular concern is that of bio-diagnosis and imaging. There is increasing use of nanotechnology on a molecular level of identification in the form of miniaturized implant devices in the body. Such devices provide a significant advantage when it comes to locating pathogens in an organism. These instruments have the potential of altering unique characteristics such as the D.N.A. The effects of such nano implants paint out the risks involved in such procedures. Therefore, adequate research and studies should be conducted to determine the level of risks involved.
Such implants would also allow the use of nanotechnologies in genetic screening and simplify the overall process. The use of nanotechnology in detection and imaging raises the ethical issues on personal freedom and level of autonomy. For example, in the case of insurance covers screening of workers could reveal an underlying condition that has not been clinically diagnosed, resulting in negative consequences for the worker. The use of nanotechnology when conducting imaging and screening warrants information and privacy concerns on what level of information should be revealed and how that affects informed consent.
References
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