What are Edible Electronics?
Edible Electronics are the intersection of technology and food. These are ingestible, biocompatible, non-toxic fabrications which can be treated as modern change in medical sciences and research spectra of the human body. It is made of biodegradable materials and can completely or partially dissolve, reabsorb or physically disappear after functioning in environmental or physiological conditions at controlled rates. Or, a class of microencapsulated electronic devices that consist of edible and nutritive inorganics and organics materials, meanwhile, that can be mainly dissolved, digested and absorbed after fulfilling the diagnosis or therapy of diseases in the gastrointestinal tract.
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History
Edible electronics is a term that has been in the field of researchers for a long time. Combining the fields of materials science, biotechnology and electronics, edible electronics realm represents a groundbreaking convergence that holds tremendous area for diverse applications, ranging from healthcare to environmental monitoring and beyond. Traditional electronic devices depend on the non-degradable, non-disposable and environment harming materials like plastics, glass, lead, manganese ions, etc. Whereas, the concept of edible electronics is based on digestible materials which are bio-degradable and non- hazardous to the environment and sometimes nutritious.
The earliest linking’s to the development in this realm was stated in late 20th century with the exploration in the concept of biocompatible materials and devices. These experiments were based on the development of biodegradable polymers and films for controlled drug delivery in human body. The major focus of this area of development was in the field of medical research which has now developed in the food industry, robotics, etc. This led to a subsequent breakthrough in demonstration of the potential for electronics to interact with biological systems without any kind adverse effects physiologically or environmentally.
Science behind the choice of materials
One of the most critical and important factors for the concept of electronics is digestibility. The ingestibility can be achieved by refinement of biological materials like proteins, digestible polymers, carbohydrates, materials which can act as safe substrates and equally functional electronics. Natural materials like collagen is one of the abundant animal proteins that is often used for tissue engineering, drug delivery.
Chitosan, a natural polysaccharide derived from chitin of crustaceans is highly compatible, degradable and antimicrobial. Biodegradable polymers breakdown into non-toxic components inside our body like polylactic acid (PLA) and polyglycolic acid (PGA). Other polymers include hydrogels (water-swollen, cross-linked polymer networks that mimic the properties of biological tissues) and silicone elastomers which are generally used in implants and prosthetics. They offer characteristic temperature withstanding and mechanical strength capability. The emergence of edible meats and composite fibres has expanded the palette range for new innovations and development and production of more edible electronics.
Edible metals like gold, silver and platinum is used in wiring and mechanics of the electronics. Several composite fibres like CFRF, bioactive glasses (for bone grafting), ceramics like hydroxyapatite and alumina are also nowadays used. Squid ink contains melanin, pigment which is present in human skin, eyes, hair which can be made ingestible through electrochemical processing and which can not only act as a battery backup for the electronics but is also highly digestible by the body. In an unlikely event, the devices gets lodged at some point in the GI tract the materials that are used are degradable.
Development in the field
There has been major development in the sector of edible electronics some of which are accounted as:
Smart pills: Edible electronic pills equipped with sensors and wireless communication capabilities can transmit data about medication adherence, vital signs and other health metrics to healthcare providers in real-time, enabling remote monitoring of patients.
Drug delivery system: Edible electronics can be designed to administer drugs in a controlled manner. These are used in monitoring a patient’s condition and release medications as needed, providing precise treatment.
Ingestible cameras: Pill sized cameras with high resolution images of digestive tract enables the working of human body when the person is alive.
Biocompatible batteries: They are used to charge the electrical devices inside our bodies. These are designed to degrade harmlessly over time. Engineering scientists at Arizona State University have used engineering and food science to invent a new way to power electronics inside the body. They’ve created super capacitors out of foods that naturally conduct electricity and demonstrated that they’re strong enough to power a camera or kill dangerous bacteria.
Edible rechargeable battery
Instituto Italiano di Tecnologia in Italy has created the world’s first completely edible and rechargeable battery. The innovative battery could be used to power edible electronics for health diagnostics, food quality monitoring and edible soft robotics. Traditional batteries consist of two electrodes called the anode and cathode. The electrodes generate an electrical current and a separator is often used to prevent the anode and cathode from touching. The battery electrolyte is a solution inside the battery that serves as a catalyst to make the battery conductive. To store these components, batteries usually have some kind of casing. The edible battery utilizes riboflavin (also known as vitamin B2 which is naturally found in foods like spinach and almonds) as an anode and quercetin (a plant pigment found in many plants and foods like onions and broccoli) as a cathode. The electrolyte is water-based and the separator is made from nori seaweed (used in sushi). Activated charcoal is used to increase electrical conductivity and a 24-karat gold leaf (like the ones used to garnish cakes) is combined with the food additive ethyl cellulose to create the conductor. Finally, edible beeswax encapsulates the electrodes to conduct the final current. Beeswax is also used for ensuring safety of consumption. The current prototype can generate up to 0.65 V of power and can run up to 12 minutes.
ELFO: Electronic Food Project
Another initiative by IIT is the ELFO (Electronic Food) Project. Funded by the European Union, ELFO aims to revolutionize food technology. ELFO is creating edible electronic systems that are safe for consumption and can also be incorporated into food products. These naturally derived devices or tags can monitor various aspects of food, such as freshness, temperature and exposure to contaminants. These tags will help in ensuring food safety and can also aid in reducing foodborne illnesses.
• Safe Ingestible Devices: Current ingestible electronics are designed to perform specific functions within the body, such as monitoring health or delivering medications. However, these devices often contain unsafe materials and struggle to pass through the digestive system. ELFO seeks to replace these materials with edible alternatives like cellulose or honey.
• Gastrointestinal Probes: ELFO envisions edible pills that act as gastrointestinal probes. These pills can study your gastrointestinal tract without endangering your health. Unlike existing toxic versions, ELFO’s devices will be safe for consumption and environmentally friendly.
• Food Monitoring: ELFO’s naturally derived electronic systems can monitor various aspects of food, including freshness, temperature and exposure to contaminants. Imagine a future where your food packaging contains edible sensors that ensure food safety.
Researchers have developed an electrochemical sensor capable of detecting biologically relevant small molecules such as catechol, uric acid, ascorbic acid, dopamine and acetaminophen. Another study developed an edible pH sensor, a radio frequency filter and a microphone. More recently, Caironi and colleagues developed an edible defrosting sensor and an edible pill for intrabody communication. Recent advances in transistors based on natural dyes and honey-gated transistors demonstrate the feasibility of fully edible circuits in the near future. The biggest advantage of edible electronics is that it done not require a health or medical practitioner to suggest and advice the health response. Not only, does it not cause any kind of immunological response to the body, unlike implanting the same materials in the human body. Ingestible devices have a lot more latitude in terms of the kinds of flexibility in materials and that allows us to innovate new battery materials, new sensing modalities and new structures for edible electronics in more broad terms.
Edible Electronics: A Common Household Name?
Making edible electronics a household name is somewhat both constructive and feasible, with the challenges and considerations in mind. The advancement in material technology, biotechnology, food technology and nanotechnology are crucial for making it more assessable, practical and promising for everyday use. The materials should not only be safe in consumption but also durable and functional. The drive-in mainstream healthcare applications can promote the use of these electronics. The merger of food industry with the electronics to make it more tangible may make users more inclined to involve edible electronics as a part of daily lifestyle.
Education and awareness, prototypes discussions and demonstrations, regulatory approvals, affordability and availability, understanding cultural aspects and lifestyle demands like that of vegans and vegetarians and last eco-friendly nature. The addressing and leverage of these factors with the efforts of researchers, manufacturers, regulators and consumers’ vision can help make achieve the household concept.
Future Scope
Oral delivery, which necessitates new natural materials capable of withstanding the enzymatic environment of the gastrointestinal (GI) tract, while maintaining suitable lifetimes remains a challenging aspect within the emerging field of edible and nutritive electronics. Currently, the discipline is in its early stages facing numerous hurdles such as effective fabrication of miniaturized capsules and enabling wireless communication with external devices. Exploring natural conductors, semiconductors and electrolytes holds promise for developing fully edible electronics. For instance, incorporating biopigments into semiconductors, creating diverse food-based activated carbons and drawing inspiration from electric eels for soft power sources show potential. Nutritive biopigments are anticipated to gradually replace inorganic materials in edible electronics. Furthermore, the establishment of more accurate theoretical and empirical models to predict the dissolution and mechanical properties of edible electronics in the GI tract is crucial.
Looking ahead, advanced biosensor and molecular imprinting technologies could facilitate the fabrication of sensors targeting specific biomarkers. Ethical and legal considerations surrounding edible electronics are likely to gain increased attention. Additionally, the widespread use of realistic GI tract simulators will expedite the evaluation of the biodegradable safety of edible electronics during degradation processes.
Conclusion
The emergence of edible electronics not only plays a crucial role in shaping future technology, but also presents a unique opportunity for interdisciplinary collaboration among young developers. This innovation has the potential to revolutionize healthcare and food industry, offering a new era of connected health, wellness and sustainability. However, as this technology evolves, it is essential to address ethical considerations surrounding privacy, data security and long-term effects on human health. From ingestible sensors to food packaging monitors, the field of edible electronics is vast, innovative and transformative.
Advancements in material properties and research indicate the feasibility of developing fully edible and nutritive electronics, utilizing combinations of edible inorganics, trace elements and food-based materials for various components. Strategies such as pH-responsive and enzyme-triggered degradable systems enable targeted delivery within the gastrointestinal tract, while theoretical and empirical models predict dissolution rates accurately. Despite recent progress in fabricating fully edible sensors for specific applications, achieving multifunctional, miniaturized and fully edible electronics remains a complex technological challenge.
References:
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