Scientists and researchers are always on the hunt for novel ways to improve our way of living that even the smallest of things like atoms and molecules matter. Just recently, interests are rising on materials the size of one billionth of a meter or 500 to 100,000 times thinner than a hair strand.
These materials, aptly called as nanomaterials, are the focal point of nanotechnology. In the advent of interdisciplinary efforts of basic sciences and engineering, nanotechnology has become an integral field in the 21st century. Nanotechnology deals with the development and manipulation of the properties of nanomaterials, which are distinguished on the basis of their chemistry and size.
Although nanotechnology is still an emerging field of study, many countries set it as a priority research field and is one of the key elements in advanced research and manufacturing. In the Philippines, it has been set as one of the priority programs of the Department of Science and Technology (DOST) and several academic institutions.
In fact, the University of the Philippines Los Baños (UPLB) launched an interdisciplinary nanotechnology studies center in 2010, now well-known as the UPLB Nanotechnology Program, “to revolutionize and create a paradigm shift for 21st century agriculture, forestry, food and industry.” Spearheaded by Dr. Milagros M. Peralta of the Institute of Chemistry (IC) of the College of Arts and Sciences (CAS), the center promotes collaborative work among researchers from the College of Engineering and Agro-Industrial Technology (CEAT), College of Agriculture and Food Science (CAFS), College of Forestry and Natural Resources (CFNR), National Institute of Molecular Biology and Biotechnology (BIOTECH), and the Institute of Mathematical Sciences and Physics (IMSP).
The program has already generated various nanomaterial-based products which can be the starting point of many novel technologies. The program has found ways to use agricultural by-products and wastes to produce materials that transcend the grassroots levels to various industries as well.
One of the thrusts of the program is the use of agricultural by-products that are often considered as waste in agricultural processing. This inspired the collaborative work of Dr. Engelbert K. Peralta of CEAT and Dr. Milagros M. Peralta in using rice hull, an agricultural waste produced in millions of tons every year. Reported as a good source of silica, rice hull was used by the researchers and their research teams to develop efficient and cost-effective techniques in nanosilica synthesis. The teams were able to make nanosilica products of high purity, large surface area, and high porosity. Several technologies were developed as offshoot applications of nanosilica.
Nanosilica-based filters for heavy metal remediation
Arsenic naturally occurs in soil, groundwater, hot springs, but more pronounced in locations of volcanic origin. It becomes toxic due to its high potential to bioaccumulate. In 2012, arsenic and its compounds were classified as a Class I carcinogen by the International Agency for Research on Cancer and were found to be linked to lung, skin and spleen cancer, as well as leukemia. One can be exposed to arsenic which has accumulated in food, drinking water, or air.
In the Philippines, a significant number of households are susceptible to arsenic poisoning because they rely on deep well and tap water as major sources of drinking water.
This paved the way for the inception of nano-based filter material pioneered by Dr. Milagros M. Peralta and her research team. They developed a method and material that can remove arsenic from contaminated water using nanosilica-based beads. Owing to its nanoscale size, high surface area, and high porosity, the modified nanosilica beads can serve as filtering media and provide a cost-effective means to effectively sequester arsenic from contaminated drinking water. This technology has potential applications in mining companies, water purifying companies, water filter manufacturers, and commercial establishments.
Protection of parts and optimization of machine operation are so important in the vehicle and equipment industry that they often use lubricants, engineered fluids, and water. Other available coolants are often petroleum- or oil-based that are typically in the liquid or gas phase and toxic to humans.
This predicament has led Engr. Ma. Cristine Conception D. Ignacio of UPLB CEAT to develop an efficient and cost-effective alternative, the nanoscale material-based coolant called “nanocoolant.”
Engr. Ignacio made a nanoparticle-based coolant that uses nanosilica from rice hull ash and combined with a base fluid, known as nanosilica-in-fluid coolant. It takes advantage of the uniformly dispersed nanoparticles that increase thermal conductivity of the fluid and has anti-clogging properties that does not damage the equipment.
The optimized method of producing nanosilica-in-fluid coolant is an affordable alternative to existing ones in the market without compromising efficacy. It has promising applications in chemical manufacturing, oil and gas, power generation, and even food and beverage industries.
Nanosilica-based fertilizer for tomatoes
For an agricultural country like the Philippines, it is important to achieve maximum crop yields in the farm. Several commodities such as tomato plants are easy to grow but are prone to diseases during the wet season. It becomes doubly difficult to optimally grow tomato plants due to unpredictable weather. This result in a decrease in production and consequent price hikes affecting both farmers and consumers. This is where the technology of Engr. Maria Morissa D. Lu of UPLB CEAT comes in to help. After putting some tweaks to nanosilica, Engr. Lu and her research team developed a nanosilica-based fertilizer for tomato plants. Silica, while not essential to plant growth, is a beneficial soil component.
The nanosilica-based fertilizer can improve the seed and germination characteristics of plants by promoting nutrient retention and high water holding capacity, thereby increasing germination and growth rate of tomatoes. It can also increase the yield of marketable fresh tomatoes as well as its resistance to unfavorable conditions.
Some farmers use rice hull as fertilizer because it has 92% silica, but the nanosilica-based fertilizer formulation makes it more efficient, cost-effective, and beneficial not only for tomatoes but also to other plants.
Fruitect® coating technology
High-value agricultural produce is often transported locally before being exported to foreign countries. Since most fresh produce are susceptible to spoilage especially during transport, distributors and exporters often rely on certain methods such as refrigeration, humidity control, and application of chemicals to prolong shelf life of their products.
Other than spoilage, there are several factors which affect the freshness of these products. To address this concern, Dr. Veronica C. Sabularse and Dr. Hidelisa P. Hernandez of the Institute of Chemistry combined their efforts to produce a safe and environmentally- friendly coating technology for mangoes and papaya called Fruitect®.
Although there are several coating technologies in the market, Fruitect® uses nanotechnology by adding nanoscaled material into the fruit coatings. They came up with two technologies – the first one is a pectin-based nanocoating from mango peels and nata de coco while the second is based on hemicellulose from pineapple crown leaves.
It is interesting to note that these technologies used agricultural by-products that most people find useless. To this date, Fruitect® is specific to prolonging shelf life of mango and papaya fruits, which are among the country’s top fruit export commodities and are summer favorites of many Filipinos.
Fruitect® won the grand prize in the recently concluded 2nd Tech Plan Demo Day 2018 of Leave a Nest conducted last May 26 at QBO Innovation Hub in Makati, Metro Manila.
Nanocrystals and nanofibers
This technology takes advantage of a natural product that abounds in the country. The inventor, Dr. Ramon Razal of UPLB CFNR came up with nanocrystals and nanofibers from locally-produced nanocellulose from bamboo. This paved the way to promising technologies that use nanocellulose and nanofibers as integral components of nanopolymer composites.
Due to its nanoscale structure, high strength, versatility, and renewable nature of their materials, nanocellulose and nanofibers have piqued the interest of researchers not only in UPLB but also in several countries around the world.
Offshoot products and innovations of Dr. Razal’s research include termiticide coatings for wood, nanopaper, biodegradable packaging, nanocellulose and nanofiber suspensions, to name a few. As an emerging technology here in the Philippines, nanocellulosic and nanofibrous technology will help in creating extensive applications.
Nanoencapsulated nutraceuticals and nosmeceuticals
Becoming more popular these days and in the advent of the emerging trend of “beauty inside out,” orally consumed nutraceutical supplements and topically applied cosmeceuticals are considered to work together to promote physical appearance and well-being.
As a pioneer of nanotechnological applications in functional food and nutraceutical and cosmeceutical research in UPLB, Dr. Evelyn B. Rodriguez, a retired professor from the Institute of Chemistry, developed a nanoencapsulated product called NanoQ.
NanoQ is a powder form of nanoencapsulated quercetin. In this technology, a naturally-occurring powerful antioxidant quercetin was encapsulated into nanoliposomal rice bran phospholipids. Analysis and evaluation of this product showed 883-fold increase in antioxidant potency, controlled and sustained release of the antioxidant to target matrix, increase solubility and prolonged storage stability.
Nanoencapsulation is a technique, in which a bioactive material or product is encapsulated into nano-sized particles. It can benefit other products because it can improve storage life and stability, control the release of the bioactive compound, and mask undesirable properties like odor and taste, among others.
This innovation paved the way for extensive research by Dr. Rodriguez and her research team into applications in the biomedical field, anti-oxidant supplementation, and nutrition and cosmetic industries.
Nanoencapsulated plant growth regulators
Another application of nanoencapsulation technology is the introduction of compounds directly to the plant itself, one of which was developed by Dr. Lilia M. Fernando of the UPLB BIOTECH. It is known as nanoencapsulated plant growth regulators or Nano-PGR.
The technology introduced by Dr. Fernando and her team uses plant growth regulators derived from plant growth-promoting bacteria which are then nanoencapsulated into a nanoliposomal matrix.
This was tested as effective for coffee, abaca, banana, and cassava. Aside from being environmentally friendly, Nano-PGR has resulted in enhanced germination and rooting of plants because it has controlled and enhanced delivery even under simulated stress environments, increased solubility in water, and high thermal stability. This technology also showed that nanoencapsulation technology is not only usable in biomedical or pharmaceutical applications but also in enhancing the potential of biological and agricultural processes.
Nanostructured film-based methane gas sensor
A common practice in the agricultural industry is to transform animal wastes to renewable forms of energy such as biogas. In fact, there are several biogas production farms already put up in some parts of the country that exploit agro-industrial wastes.
During biogas production, methane is produced for cooking, heating, or lighting. Despite its uses, methane is a toxic gas that is difficult to detect and monitor especially in confined areas where it can build up. Once methane accumulates in the air, it can pose harm to the workers in a biogas facility, the people, and the communities near it due to its relative low explosive limit.
A very useful tool was developed by Mr. Emmanuel Florido of IMSP to counter the risk of methane buildup. He developed a sensor using zinc oxide which can detect methane in biogas-producing farms. By carefully controlled particle size, the sensor can detect and quantify methane and other hydrocarbons even in minute concentrations.
This field sensor has also great potential in applications for detecting other noxious and toxic gaseous compounds such as ammonia and butane with potential use in industrial plants and factories.
Most of the technologies are being refined to make them more accessible and user-friendly to the public. Nonetheless, nanotechnology remains a promising enabler and catalyst of many possibilities, which can help us realize a wide spectrum of applications not only in engineered materials, nanomanufacturing, electronics, and communication, but also in energy, environment, biomedicine, food, and agricultural systems.
These applications were considered outside the realm of possibility before but in the recent years, nanoscience and nanotechnological applications have been a “game changer” owing to the high potential of developed technologies and innovation in advancing the human experience.
Hence, through the UPLB Nanotechnology Program and other academic institutions who have been scaling up materials that cannot be seen by the naked eye, the abovementioned technologies can help the country rise up to the demand of transformative technologies to make a big impact on people’s lives. ■