Nanobiotechnology Advances: Fusion of Enzymes and Nanotechnology
By Associate Professor John Lau Sie Yon and Shamini Anboo
Nanotechnology is a promising research field that provides a novel platform in life science, material development and biotechnology. Organic-inorganic hybrid nanostructures are a recent advancement combining two major technologies, namely biotechnology and nanomaterials.
Nanoscale biocatalysts are synthesised via the fusion between organic molecules (enzymes or proteins) and inorganic metal ions which exhibit promising catalysis characteristics for various industry processes.
The integration of enzymes with nanomaterials is aimed at enhancing enzymatic activity and preserving its structural conformation. Hybrid nanostructures have shown encouraging results in stabilising enzyme activity, promoting targeted drug delivery, and developing various effective biosensors and cell imaging technology in biomedical applications.
Hybrid nanoflowers provide unique flower-shaped, porous structures with a larger surface-to-volume ratio in comparison to traditional spherical-shaped nanoparticles. Some of the hybrid nanoflower systems have been reported to have higher stability, reproducibility and physical properties compared to conventional nanomaterials.
Some substantial research has been done on the application of nanotechnology in the agricultural sector, especially in crop protection. There is extensive interest in biopolymers such as chitosan because of its antimicrobial and antifungal properties. Metal hybrid nanochitosan is reported to exhibit superior physicochemical characteristics that provide enhanced biological activities. For instance, nanochitosan particles are incorporated with antimicrobial inorganic metal ions such as silver ions (Ag+) to inhibit the systemic propagation of viruses and viroids throughout the plant and enhance the host’s hypersensitive response to infection.
In the food processing industry, researchers have demonstrated the potential of magnetic nanoparticle-bound lipase enzyme for the hydrolysis of fish oil to produce omega-3 fatty acids. Nanobiocatalysts show excellent biocatalytic activity and selectivity for DHA and EPA. It has been reported that an average of 90 per cent DHA enrichment of the fish oil was achieved even after reuse of 20 cycles for real substrate hydrolysis.
This technology creates an opportunity for the local palm oil processing industry to apply nanobiocatalysis systems for selective hydrolysis of palm oil saturated fatty acids. These nanobiocatalysts can also be further developed with the addition of Phospholipases A1, A2, B, and C for effective degumming to remove phospholipids and improve the edible oil yield.
In the medical and healthcare industries, the use of enzyme-incorporated hybrid nanostructures is very promising, especially in the detection and monitoring of acute diseases such as Diabetes Type II, cancer cell markers, cardiovascular diseases, as well as Alzheimer’s and Parkinson’s. The production of biosensors and/or biomarkers is an alternative, cutting-edge technology in comparison to traditional methods such as colorimetric sensors and protein biomarkers. Some advantages of hybrid nanostructures include ultra-sensitivity, improved viability, stability and extended shelf-life of these proteins.
Enzyme-incorporated hybrid nanotechnology has also been studied and is currently being implemented in the monitoring and control of air and water pollution. Enzyme-based nanobiosensors are a potential alternative owing to their advantages over other traditional chromatographic analyses. Enzyme-based nanobiosensors are economical, user-friendly, highly sensitive, accurate and large-scale enabled. Examples of toxic air pollutants include CO2, NOx, ammonia, dioxins and volatile organic compounds (VOCs). Large quantities of dioxins present in the air affects the immune and endocrine systems and are carcinogenic to human health.
Enzyme-incorporated hybrid nanomaterials have also been developed as biosensors to detect toxic gases such as phenolic compounds and hydrogen peroxide. In terms of wastewater treatment, the effect of various industry dyes such as, red 1, red 9, yellow 14, crystal violet, methylene blue and basic yellow on human health has been found to be dangerous as they can cause carcinogenic activity and allergic reactions. Therefore, enzyme-based nanotechnology can be implemented to overcome the current limitations of low adsorbents.
The primary water and soil pollutants are heavy metals, such as zinc, cadmium, aluminium, lead, mercury, as well as pesticides such as endosulfan sulfate, atrazine, chlorpyrifos and diethyl atrazine.
These environmental issues have spurred scientists to incorporate biological components into existing nanosystems to enzymatically degrade or decompose wastes before disposal. Nanoparticles can enhance electron transfer and conductivity, and offer biocompatibility and catalytic efficiency, therefore composing inhibition biosensors with high sensitivity.
It is obvious nanobiocatalysis technology has a bright future as well as unique challenges. These challenges include uniformity of synthesised nanoparticles, high leaching of biocatalysts on the surface of nanoflowers, and reusability and stability of nanoscale structures. These factors could affect the performance of the enzyme.
The nanobiocatalyst technology is still under intensive research at Curtin Malaysia by a team of researchers led by Associate Professor John Lau Sie Yon. In order to enhance biocatalysis performance, Associate Professor Lau’s team has explored different binding agents which could provide porous structures that promote high mass transfer rate between the substrate and enzyme, interaction between molecules, as well as improve enzyme loading and the electron transfer to the active site. The hybrid nanoflower structure also provides an additional protection layer for enzymes or proteins in extreme conditions such as strong acidic conditions and high temperatures.
One of the postgraduate research students in the team, Shamini Anboo, is studying the potential of nanobiocatalysts in biofuel conversion. This Ministry of Education FRGS (Fundamental Research Grant Scheme) funded project focuses on the development of versatile nanoflower structure membrane sheets for the conversion of waste cooking oil into biofuel through a transesterification process.
The team believes the research has great potential and its findings could make a significant impact on society and the environment, ultimately contributing to the United Nations’ Sustainable Development Goals (SDGs). The team’s future focus includes exploring the field of reusability of nanobiocatalysts and optimising the performance of nanobiocatalysts relative to their price, activity, selectivity and stability.
Associate Professor John Lau Sie Yon is Associate Dean of Research and Development of Curtin Malaysia’s Faculty of Engineering and Science. He is actively involved in teaching, research, supervising High Degree by Research (HDR) students, and providing academic leadership and administrative support for the Faculty’s Chemical & Energy Engineering Department. His research focuses on bioprocessing, especially on enzymes technology and nanobiocatalyst development and applications in various industry processes. He has received a number of national research grants and has authored and co-authored numerous high–impact academic journal articles and conference papers on related topics. He is a Chartered Engineer (CPEng) of Engineers Australia (EA) in Chemical and Environmental Engineering and is a Fellow of the Higher Education Academy, UK. Associate Professor Lau welcomes opportunities for partnerships and collaboration from interested parties and can be contacted by email at johnlsy@curtin.edu.my.
Shamini Anboo is a PhD student at Curtin University Malaysia under the supervision of Associate Professor Lau. She is currently working on the research team’s hybrid nanoflower biocatalyst project.
