Mechanical engineering, known for its scientific theories and mathematical analysis methods, has found itself in other disciplines and has become important in understanding several problems. One of those disciplines is medicine and biology.
Mechanical engineering covers topics related to energy, fluid mechanics, dynamics, robotics, solid mechanics, heat transfer, design and manufacturing, maintenance and control. This diverse background helps mechanical engineers, as well as scientists in the mechanical field, to play a critical role in solving global issues and challenges of many areas of interest outside mechanical technologies.
Medical areas such as pharmacokinetics and pharmacodynamics would not have emerged without the principles of mechanical engineering. In fact, mechanical engineering principles are now deemed fundamental in understanding areas in immunology, orthopedics and cardiovascular physiology. The combination of new techniques and disciplines have paved the way for the merging of mechanical engineering and medicine. Such a notion would be hard to imagine two decades ago.Current Technologies
Biomechanics is the application of mechanical principles in the study of living organisms including their kinematics (description of motion) and kinetics (actions of forces associated with motion), it views the human body as a collection of levers, made of bones which are moved by its muscles. In sport, mechanics can be involved to analyze the performance of athletes based on their interaction with the equipment.
According to the scale in which the study or the application is done, we can distinguish between biomechanics and mechanobiology. Biomechanics focuses more on body segments and their interaction with the surrounding environment while mechanobiology is concerned more with the level of cells-it dwells on the behavior of physical forces and transfer in cells and/or tissues.
Nanotechnology is understanding the behavior of matter at infinitesimal dimensions called nanometers (a nanometer is one-billionth of a meter; a human hair is about 75000 nanometers in diameter), where incredible properties enable emergent applications. Considering the combination of nanoscale science, engineering, and technology, nanotechnology covers sensing, imaging, measuring, manufacturing, control and manipulating nanoscale matter. In mechanics, the integration of nanotechnology is focused on three main topics including nanostructures (carbon nanotubes), nano-fluids and microfluidics, and nanorobotics. The application of these Nano-mechanics topics in medicine and biology is presented below.
Carbon nanotubes (CNTs) are nanoscale structures made of pure carbon that are long and thin and shaped like tubes. These molecules are the same sized and structured in chemical bonding and aligned by Vander Walls forces into ropes. The length of CNTs can reach a few millimeters while its diameter is in the order of a few nanometers.
Cancer is arguably one of the most complicated diseases in the world. World Health Organization (WHO) declares cancer as one of the main causes of morbidity and mortality worldwide, with approximately 14 million cases in 2012. Anticancer drugs like Chemotherapy or Radiotherapy often have physiological, biochemical and cellular toxic side effects. Carbon nanotubes have unique mechanical properties that strongly minimize the effects of many therapeutics.
Taxoid is a chemotherapeutic agent to block proliferating cancer cells. Carbon nanotubes have been explored as a tool in nanocarriers for the exploration of novel drugs. There are large varieties of nanoscale drug delivery vectors like single-walled carbon nanotubes (SWCNTs). As CNTs are needle-like shape, they have been involved in injection and integration into target cells. Also, CNTs are combined with the anticancer agent toxoid as a cleavable linker. In order to ensure the target cell, the drug is transported via endocytosis and released into the cell. Microtubules interact with the drug as evaluated by flow cytometry thus formatting a stable microtubule-toxoid complex.
Another novel application of carbon nanotubes is a drug delivery method called smart drug delivery. This is a method of high recognition of cancer cells or cancer tissues in order to deliver medication with high precision. It is efficient for the lymphatic system; metastases of certain cancers can be effectively inhibited by subcutaneous injection. Absorption on the PAA-CNT surface is possible through co-precipitation of Fe3O4-based magnetic nanoparticles, polyacrylic acid (PAA) can be added to CNTs to become highly hydraulic.
In the "longboat" anticancer system, carbon nanotubes are used for cancer treatment based on a functionalized single-walled nanotube attached to a complex mixture of cisplatin and folic acid derivative via covalent or noncovalent bonding to comprise the longboat which has been reported to be taken up by cancer cells via endocytosis.Challenges and Outlooks
Nanotechnology has advanced in theoretical and practical research in all fields of biomedicine. Cancer treatment gained new grounds as the line between nanotechnology and immunotherapy continues to blur. Carbon nanotubes antibodies now exist that can identify and destroy tumor cells. Many experiments have been done to show the possibility of anticancer immune reaction increase of tumor cells by using CNTs as delivery media.
The ongoing development of computer technology allows the increase of mesh resolution of numerical models used in computational fluid dynamics. Indeed the blocker that inhibits the growth of such promising technology is the technology of computers. But as long as Moores Law is true, we can expect more advancement in this field in the future. This is also true for mechanical engineering in biology and medicine as a whole.