INTRODUCTION:

The word "nano" comes from the Greek word "dwarf". In 1959, Nobel Prize-winning physicist Richard Feynman proposed the concept of nanotechnology in his lecture. "There's Plenty of Room at the Bottom."

Since then, nanotechnology has been used in a variety of applications, including dental diagnosis, materials, and treatments. In 1974, a student at Tokyo's science university coined the term nanotechnology.

The study, creation, manipulation, synthesis, and application of materials, systems, and technologies at the nanoscale is known as nanotechnology. The best way to characterize nanotechnology is as an explanation of atomic and molecular activity with practical uses. In a number of industries, including engineering, agriculture, construction, microelectronics, and health care, to mention a few, its importance is growing. The use of nanotechnology in healthcare has drawn a lot of attention lately. These days, many therapies need a substantial financial and time commitment. Treatments can now be developed more quickly and affordably thanks to nanotechnology.

Nanorobots also known as nanobots are tiny gadgets made to protect or cure human health issues. This tiny gadget has been engineered to precisely carry out a certain operation or tasks at nanoscale dimensions. To perform duties in industrial and medicinal settings, they must operate at the atomic, molecular, and cellular levels. In accordance with the belief that "nanorobots are microscopic in size, it would probably be necessary for very large numbers of them to work together to perform microscopic and macroscopic tasks". The creation of a nanorobot drug delivery system could result from developments in robotics, nanotechnology, bioinformatics, medicine, and computers. Respirotomes, microbivores, pharmacyte nanorobots, surgical nanorobots, clottocytes, and cellular repair nanorobots are a few types of nanorobots.

The human body will be maintained and protected from illnesses by nanorobots. They will consist of bits that range in size from 1 to 100 nanometers, with a diameter of 0.5 to 3 microns. Carbon is the most widely used element in nanorobots because of its strength and inertness in the form of fullerene and diamond. The passive diamond covering on the outside of nanorobots is designed to protect them from host immune system attacks. Because they are invisible to the unaided eye, they are challenging to manage and regulate. We are able to detect the molecular structure of these nanoscale devices through the use of visual and tactile interfaces made possible by techniques like Atomic Force Microscopy (AFM) and Scanning Electron Microscopy (SEM). Researchers in nanoscience and biotechnology are investigating virtual reality (VR) as a means of enhancing perception and achieving telepresence. The construction and control of nanorobots and nanomachine components are the most challenging aspects of their development. A perfect nanorobot should have pieces that measure between 1 and 100 nm in size, and its size should be between 0.5 and 3 microns. Anything larger than that can impede capillary flow. Its passive diamond exterior shields it from immune system attacks.^1,8,9,13

Advantages:

· Nanobots offer numerous advantages compared to traditional drug delivery methods.

· Nanobots are incredibly specialized and precise with less adverse effects.

· It releases medication in a regulated manner.

· It also reduces surgical blunders.

· The benefits of computer-controlled medicine distribution include faster action times.

· The nanorobot's maximum size is 3 microns, allowing it to circulate freely through the body without interfering with capillary blood flow.

· Use of nanorobot medication delivery devices will improve bioavailability.

· Targeted therapy involves treating malignant cancer cells.

· Access parts of the human body which is inaccessible from the surgeon's operating table.

· Because drug molecules are transported by nanorobots and released as needed, the benefits of large interfacial areas during mass transfer can be obtained.

· Drug inactive in places where therapy is not needed, reducing unwanted side effects.

· There is less post-treatment care necessary because it is a minimally invasive approach.^1,2,9

Disadvantages:

· The biggest disadvantage of designing nanobots is their high cost and complexity. The most challenging issue is the power supply.

· More research is needed to help nanobots overcome the body's immunological reaction

· Terrorists could misuse nanobots to create bio-weapons, posing a threat to society.

· Nanobacterias existing in the body can have catastrophic consequences, indicating that nanobots are not native to the body.

· The presence of numerous foreign particles in the body poses a considerable challenge for biodegradability.

· To overcome these disadvantages, careful consideration is necessary.

· Self-replicating nanobots have the potential to develop dangerous versions, putting our immune system at risk.^2,10

INTRODUCTION TO CANCER:

Cancer is a broad category of over 100 diseases characterized by uncontrolled cell growth and division. It can develop in any body tissue and has distinct characteristics depending on its type. The term "cancer" comes from the Greek word "korkinoma," and its understanding has evolved since observations by Hippocrates over 2,300 years ago.

Key historical findings include the increased incidence of scrotal cancer in chimney sweeps in the 1770s and a rise in lung cancer among pitch blende miners in the mid-1800s, highlighting potential environmental causes. These discoveries suggested that cancer could have identifiable and preventable origins.

In a healthy body, about 30 trillion cells cooperate to regulate growth, only proliferating when instructed by other cells. Cancer disrupts this balance, allowing cells to divide uncontrollably.^19,20,21

NANOROBOTS IN CANCER TREATMENT:

As cancer continues to affect people globally, advanced treatment methods are urgently needed. Nanoscience and nanomaterials offer promising alternatives to traditional treatments like radiation and chemotherapy. Nanomaterial-based therapeutics enhances bioavailability, improve cancer cell responses, and reduce side effects.

These materials can exploit the enhanced permeability and retention effect, allowing them to accumulate in tumors. Key properties include their small size, which helps avoid detection by macrophages and prevents rapid leakage, as well as their ability for targeted drug delivery. Engineered nanomaterials, such as DNA/RNA components, silk fabrications, and liposomes, are used for effective treatment. Additionally, inorganic nanomaterials combined with photothermal therapies show potential in cancer treatment. Overall, nanotechnology represents a significant advancement in cancer therapy.³

Nanobots represent a promising advancement in cancer diagnosis and treatment due to their ability to specifically target diseased cells while leaving healthy cells unharmed, thus minimizing side effects. Equipped with embedded biosensors, these nanobots can detect tumour cells at early stages. One innovative approach involves genetically modified salmonella bacteria carrying microscopic robots, or "bacteriobots," that are attracted to tumours by chemicals secreted by cancer cells. These deliver drugs directly to the tumour, primarily effective for breast and colorectal cancers.

In contrast, nanobots can be tailored to detect and treat various cancers by modifying their construction to target different cell surface receptors. They are engineered from DNA strands that change shape to release therapeutic payloads upon activation.

Additionally, nanobots can obstruct blood flow to tumours, which is crucial for their survival. Made from a flat DNA sheet containing thrombin, these nanobots attach to tumour-specific proteins on endothelial cells, penetrate blood vessels, and release thrombin to initiate clotting. This process effectively reduces blood supply to tumours, starving them of necessary nutrients.^{6, 17}

Materials of nanorobots:

The key aspect for the construction of nanorobots was the biocompatibilities of materials at nanometer scales to function within tumour tissues and cells. The initial difficulty in creating a nanorobot that can materials science is a problem in medical tasks surface science, given that micro robot’s functioning is mostly determined by the characteristics of its surface and materials. The relationship between molecules in biological species and a nanorobot's surfaces significantly impacts a nanorobot’s ability to control its mobility in a biological microenvironment. Most nanorobots are composed of materials that are biodegradable or biocompatible. These bio degradable substances have the ability to evaporate or dissolve at the conclusion of their assignments. They should be able to do a variety of precise functions in the interim, such as detecting the presence of tumour, cells or tissues, delivering and release of nanocargoes in response to physical stimulation signals, specific disease indicators, and shifts in local temperature pH levels, temperatures, etc. These resources ought to additionally be pliable and malleable to guarantee viability mechanical characteristics of nanorobots to function in the biological habitats for humans. They require having greater mobility in three dimensions and viscous and flexible bodily fluids, as addition to in virtual organs. Additionally, when creating nanorobots that can carry out adaptive duties across an array of diverse biological contexts the importance of stimulating-responsive materials increases significant.^4,11,12

Fabrication of nanorobots:

Their straight forward shape and production processes were the foundation of the first generation of nano-engines used in small-scale robots. By use of electrochemistry reduction of metal-corresponding salts inside nano, these initial nanorobots were made of micron symmetric pores. Self-assembly is an additional tactic that nanocomponents assemble layer by layer. When these materials are successively charged, the production of owl-shaped stoma formed by self-organizing polymer colloids to form cells having interior gaps that can be filled with catalytic materials, magnetic connections and engineered structures.

Using a thin film layer on a template to create an asymmetric coating structure is another method for creating nanorobots. From metal to plastics beads, these approaches make use of different commer readily accessible microtemplates, in addition to biological and templates with a bioinspired design. 3D printing, viewing perspective roll-up lithography, deposition, and other cutting-edge methods are also applied in the creation and manufacturing of more intricate nanobots. Every one of these recent innovations offer cutting-edge design and great quality, while they are often more expensive and are limited in their material choices.

Biohybridnanorobots were manufactured with varied methods. In recent studies, for instance, noncovalent interactions were frequently used to attach synthetic elements to a microorganism's head or tail. Biohybridnanorobot consist of live creatures and artificial elements, which were combined by self-assembly propelled by electrostatic interactions. An additional strategy gains from the tangible retention of functional nanostructures on the abrasive microsurface organisms. However, because covalent bonds are absent, in the space between the microbial surface and the synthetic substance, under certain environmental stressors, it tends to flake off. ^4,7,19

Propulsion of nanorobots:

The energy source of driving forces is vitally important for nanorobots to work in the body autonomously. The type of driving force can affect the moving speed of a nanorobot, controllability and biocompatibility to a great extent and thus subsequent applications in a biosystem. It is not possible to apply the conventional macroscopic batteries and power supply components to these nanorobots. In the design phase, it should be ensured that a nanorobot could move freely and has sufficient power to offset the resistance from TME (tumor microenvironment). The power sources of nanorobots are innovatively divided into exogenous dynamics and endogenous dynamics.

Exogenous dynamics usually include magnetic propulsion, ultrasound propulsion, and light-driven propulsion, whereas endogenous dynamics are usually achieved by chemical or biological reactions. Locomotional control also represents a important challenge in micro- and nanoscales. In vivo operations of nanorobots have been demonstrated their abilities to enhance tissue penetration and payload retention. But viscous forces dominate over inertial forces at nanoscopic scales. Therefore, it is necessary to take into account the environment effects while designing an efficient nano-machine. For example, it requires different swimming strategies that allow nanorobots to operate under these low Reynolds number constraints, as well as various kinds of navigation strategies for nanorobots to overcome the Brownian motion.

Recently, blood glucose, urea and other bodily fluid constituents were utilized as the power sources for enzyme reaction-derived nanorobots, but the stability of these enzyme reactions-driven nanorobots requires further improvements before practical implementation can be possible. However, new alternative fuels and propulsion mechanisms are needed to achieve safe and successful operation in the human body, although different fuels and external stimuli have been explored for nanorobots in aqueous media. ^{4, 20}

Working methodology of nanorobots in cancer treatment:

Over time, several groups have written articles about the precision of nanobots and efficiency in identifying and curing cancerous cells. Maheswari et al. suggested nanobot in their investigation that could use a positron beam to identify malignant cells in vivo test using emission tomography. Additional research has also demonstrated that power-driven nanobots may be more precise in identifying malignant cells with higher accuracy, control, precision, and so forth. Generally speaking the use of nanobots in cancer therapy has been developing to higher levels because of developments in nanoscience as well as nanotechnology, health, and materials scientific fields. Let's now examine how nanobot operate inside a person's body.

The intravenous approach has been the most often used technique for introducing nanobots into a patient's body during clinical studies. Additionally, some research has reported that ingesting techniques can be used to cause them through the person's oral cavity. Prior to administering, when nanobot enters a person's body, it's crucial that it must link to the induced bots, in order to examine, research, and comprehend the movement, operation and issues that the nanobot encounters within the body. When treating cancer, the nanobots are propelled by certain forces within the body, including external forces such as magnetic and ultrasonic forces driven by biology, hybrids, and so forth continue. The fact is that anticancer medications like paclitaxel, cisplatin, etc., can have adverse effects. The main chemotherapy treatment cycle consists of absorption and metabolism with a pause for the body to re-establish itself before the subsequent session. Pharmacokinetics (the most common technique for cancer therapy), which calls for two-week rounds, in the instance of little tumours. They also have a tendency to side symptoms such fatigue, light-headedness, nausea, hair loss, and so forth, attacking both healthy cells and inside cells the body in addition to the malignant cells. Here, nanobots are likely to be viewed as the more sophisticated version of cancer treatment since it is believed that nanobots can to examine and diagnose the body in a week.

Programmed nanobots with assessed number and quality are activated and guided to the intended bodily location. The nanobots are directed throughout a person's body while they are not in use. Once it has passed through a person's body, as seen in, they build up on the malignant cells. Currently, the nanobots will be in their non-state. They are brought into the ON condition, once the operator has received the appropriate command. Then they open, and the payloads are deposited as a result on the specific cancer cells. Following the deposit of the payloads, it goes back to being in the off position. Although not entirely feasible at this time, because they can become complex inside the human body, nanobots employed for therapeutic purposes should be closely watched long term, therefore they need to be routinely observed as the substances utilized could prove to be dangerous, over time, as well as the control of propulsion and targeting may eventually prove hazardous as well.^4,15

Benefits of nanorobots over chemotherapy:

The primary characteristic of neoplastic cells is their ability to divide quickly, which is how conventional chemotherapeutic drugs function. For this reason, chemotherapy also harms healthy, normal cells that divide quickly such as bone marrow cells, macrophages, intestinal system, as well as hair follicles. The traditional inability of chemotherapy is to provide selective effect solely to the malignant cells. This leads to common adverse effects of the majority of chemotherapeutic drugs that comprise myelosuppression, which occurs when the production of white blood cells that inhibit the immune system, mucositis, or inflammation of the digestive tract's lining tract, organ failure, alopecia (hair loss), and even thrombocytopenia or anemia. These adverse consequences occasionally enforce dosage reduction; postpone treatment, or stopping the prescribed treatment. Moreover, chemotherapy drugs frequently fail to enter and reach the core of solid tumours, killing the malignant cells.

Conventional chemotherapy drugs are frequently removed from the bloodstream by macrophages. As a result, they stay in use for a very brief and unable to communicate with the malignant cells, rendering the treatment totally useless. Another significant issue is the medication’s weak solubility in traditional chemotherapy, which prevents them from break through the membranes of living things. An additional issue is linked to the multidrug P-glycoprotein, resistance protein that is surface-overexpressed of the malignant cells, preventing medication buildup within the tumour, serving as the efflux pump, and frequently facilitates the growth of resistance to cancer-fighting medications. Consequently, the administered drugs don't work or don't provide the intended output.^5,16

Application of nanorobots in cancer treatment:

An early diagnosis will increase the patient's chances of receiving treatment for cancer.
In the early stages of cancer growth, tumour cells are found using nanorobots equipped with chemical biosensors, or nanosensors. This nanosensor can detect the existence of cancerous cells within the body. Most anticancer medications have a narrow therapeutic index, which makes them toxic to normal stem cells cellular, gastric, and unfavourable hematological consequences, among others. The primary mechanism of action of chemotherapy drugs is the destruction of rapidly proliferating cells characteristic of cancerous cells. Doxorubicin, one of the most used anti-cancer medications, is used in several forms of cancer, like Hodgkin's disease (HD), where treatment is given inused with additional antitumor medicines to lessen their toxicity. Given their ability to maneuver as blood-borne instruments, nanorobots can aid in several crucial areas of cancer treatment. Early tumour cell identification can be accomplished using nanorobots equipped with chemical biosensors within the body of the sufferer. For this kind of work, integrated nanosensors can be used to determine the ecadherin signal's strength. Thus, nanotechnological based hardware architecture; the use of bioelectronics in nanorobot cancer therapy is explained. The salmonella germs that have been genetically altered by scientists are attracted to tumours by substances released by cancerous cells. The bacteria harbor roughly three tiny robots tiny particles that, when the bacteria present, release medicine-filled capsules automatically arrive at the tumour. The patient is spared the negative effects of chemotherapy since the nanorobot which the researchers termed “bacteriobots”, targets the tumour directly while sparing healthy cells.^1,6,15

CONCLUSION:

Because radiation and chemotherapy have serious adverse effects, nanorobots from the field of nanomedicine can be a novel, helpful, and hopeful piece of equipment for patients in the detection and treatment of life-threatening diseases and illnesses. The focus of medicine will eventually move from medical science to medical engineering, where the revolution will come from nanorobotic technology. Utilizing Nanorobots from curing sickness to slowing down the aging process, medicine has a lot of promise (problems associated to aging, bone loss, and wrinkles can all be treated at the cellular level). Another option for industrial use is the nanorobot. They'll offer customized medicines that are not currently available but have higher efficacy and fewer negative effects. Together with combined action, they will offer imaging agents that function as medications, surgery with immediate diagnostic feedback, and pharmaceuticals offered with diagnostics.

Even though this science seems like fiction right now, However nanorobotics holds great promise for transforming healthcare and treating illnesses in the future. It creates new avenues for extensive, copious investigation. Future medical treatment will utilize delicate new diagnostics for a better evaluation of individual risk. If the key diseases that burden the aging population the most cancer, musculoskeletal disorders, neurological and mental diseases, diabetes, and viral infections are treated early, the greatest impact can be anticipated.

REFERENCES:

1. Kumar SS, Nasim BP, Abraham E. Nanorobots a future device for diagnosis and treatment. Journal of Pharmacy and Pharmaceutics. 2018 Feb 1; 5(1): 44-9.

2. Viswanathan SM, Rajan AR, Rajan R. Nanobots in medical field: A critical overview. Int J Eng Res Technol. 2019; 8: 65-8.

3. Kong X, Gao P, Wang J, Fang Y, Hwang KC. Advances of medical nanorobots for future cancer treatments. Journal of Hematology and Oncology. 2023 Jul 14; 16(1): 74.

4. Pradeep P, Sonia MM, Kizhakkepeedika RD. Nanobots in Cancer Treatment–Framing Lung Cancer. Journal of Advanced Lung Health. 2024 May 1; 4(2): 57-69.

5. Naik MH, Satyanarayana J, Kudari RK. Nanorobots in drug delivery systems and treatment of cancer. Characterization and Application of Nanomaterials. 2024 Aug 28; 7(2): 2539.

6. Rifat T, Hossain MS, Alam MM, Rouf AS. A review on applications of nanobots in combating complex diseases. Bangladesh Pharmaceutical Journal. 2019 Jan 31; 22(1): 99-108.

7. Battistella C, Klok HA. Controlling and monitoring intracellular delivery of anticancer polymer nanomedicines. Macromolecular bioscience. 2017 Oct; 17(10): 1700022.

8. Sanjay S. Patel, Poojan N. Patel. A Brief Review on Nanorobotics Applications in Medicine and Future Prospects. Asian Journal of Research in Pharmaceutical Sciences. 2023; 13(1): 19-8.

9. Lalita Balasaheb Patil, Swapnil S. Patil, Manoj M. Nitalikar, Chandrakant S. Magdum, Shrinivas K. Mohite. A Review on-Novel Approaches in Nanorobotics. Asian J. Pharm. Res. 2016; 6 (4): 217-224.

10. Srinivas P, Mounika G. Int J Nano Dim. 2011; 2(1): 1-15.

11. Raghvendra, Tyagi S, Yadav P, Saxena S. IJABPT. 2010; 1(2): 660-65.

12. Abhilash M, Nanorobots.International Journal of Pharma and Bio Sciences. 2010; 1(1).

13. Michael Haji. The role of engineering in nanotechnology, Sheikh Electrical Engineering, Department Northern Illinois University.

14. Rohit Kumar. Applications of Nanorobotics. International Journal of Scientific Research Engineering and Technology (IJSRET). 2014; 3(8): 2278

15. M K Sharma and R Gupta, Nanorobotics the future of medicines. Research in Pharmacy and Health Sciences. 2016; 2: 2.

16. Mohammed Abrar, Tajim Sheikh, Suleman Mohammed, Farooqui Muzaffar Ahmad, Ubaid Shaikh. Nanorobotics in Cancer Treatment: A Review. Res. J. Pharma. Dosage Forms and Tech. 2019; 11(1): 43-46.

17. D. Karthik Raaja et al, A Mini Review On Nanobots In Human Surgery And Cancer Therapy. IJSRME.

18. Abhilash M. Nanorobots. International Journal of Pharma and Bio Sciences. 2010; 1(1): 1-10.

19. Nandkishor et al. Review on application of Nanorobots in health care WJPPS. 2014; 3(5); 472-480.

20. Khulbe P. Nanorobots: A Review. Int J Pharm Sci Res. 2014; 5(6): 2164-73.doi: 10.13040/IJPSR.0975-8232.5(6).2164-73

21. Umai et al. A Review on DNA nanobots – a New technique for cancer treatment. Asian J Pharm Clin Res. 2018; 11(60: 61-64.

Received on 14.10.2024 Revised on 30.10.2024

Accepted on 16.11.2024 Published on 10.12.2024

Available online on December 17, 2024

Asian J. Res. Pharm. Sci. 2024; 14(4):401-406.

DOI: 10.52711/2231-5659.2024.00063

This work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License. Creative Commons License.