A Frugal Engineering Green Chemistry Approach for Better Detection of Toxic Metal Ions

The SSSIHL Research team, led by Asst. Professor, Dr. Sai Sathish Ramamurthy, has published a new paper in ACS Applied Nano Materials that explores the use of a novel biopolymer, Lycoat®, to synthesize silver nanoparticles via a frugal disruptive approach. The augmented enhancements obtained from these nanoparticles were utilized for mobile phone-based attomolar sensing of environmentally hazardous mercury (Hg2+) ions.

Identifying the Issue

• Chemical, microwave and sonication assisted synthesis of nanoparticles have been used frequently. However, the advantages of UV light, an abundant renewable natural source, is seldom discussed which is significantly conducive for the synthesis of nanomaterials
• Metal ions in unregulated concentrations wreak havoc in the ecosystem by entering the food chain. The alarm with regard to mercury poisoning has been raised world-wide and several methodologies are adopted for detection of Hg2+ ions at extremely low concentrations for early diagnosis and environmental monitoring
• There is an urgent need of a frugal science based disruptive technology for the fabrication of nanomaterials to be used in translational applications that are rapid, low-cost and user-friendly, portraying high sensitivity and specificity

Objective of the Research

• Identifying eco-friendly and cost-effective approach for the synthesis of nanoparticles with defined geometries and anisotropy that can aid in achieving augmented fluorescence enhancements
• Improving the sensitivity and specificity of the sensor materials in comparison with the cost intensive and hazardous technologies that are currently being utilized. Sensors are extensively used in environmental health monitoring, public health control, industries and homeland security

Who should read this?

Anyone in industry, working directly or indirectly on sensor development or sensing related technologies including, security, surveillance, monitoring, environmental safety monitoring and medical technologies

Bio-Nano Inspired Anisotropic Interfaces- A Frugal Engineering Green Chemistry Approach

• The eco-friendly and biocompatible methodologies for diverse applications in nanophotonics and biomedical domains are discussed in this work
• Lycoat® is a plant derived biopolymer that complies with the European directive on food additives & USFDA and consequently is considered as a natural food ingredient. It is beneficial for use in patients (wound dressings), consumers and has found useful applications in food, nutraceutical and pharmaceutical industries. Even though Lycoat® has been used extensively in the industries, it has so far not been explored for the green synthesis of anisotropic nanoparticles
• Three main challenges in the development of nanotechnologies have been addressed theoretically and experimentally in this work. The biosynthesized nanomaterials present: (i) non-toxic bio-inspired frugal science approach for synthesizing nanoparticles, (ii) obtaining augmented fluorescence emission enhancements using anisotropic nanoparticles, (iii) development of sensors with high sensitivity and specificity for the detection of hazardous heavy metal ions

Key Features and Benefits

• Bio-inspired synthesis route for nanoparticles
• Synthesis of anisotropic nanoparticles with defined geometries using a green synthesis nano-approach
• Bio-inspired approach in surface Plasmon-coupled emission platform by utilizing the synthesized nanofractals and nanocubes in three different SPCE interfaces- spacer, cavity and extended cavity architectures
• The multifold nanogaps generated by the nano-engineered hybrids sustain innumerable hotspots catering to attomolar sensitivity of the fluorescent dye molecule, rhodamine B
• The proposed green nanotechnology platform is useful in the sensing of heavy metals that are hazardous to the environment and human health

Impact

• A simple, cost-effective, frugal methodology is adopted to synthesize silver nanoparticles using a plant derived biopolymer- Lycoat® and applied them on a conventional existing sensor technology based on plasmonic platform
• The silver nanofractals (AgNFs) and silver nanocubes (AgNCs) synthesized here using a biocompatible Lycoat® polymer would be of immense use as antibacterial, antifungal, anti-oxidant, anticancer, and antiviral agents
• The well-known ability of the biocompatible Lycoat® polymer as films, and their ability to yield AgNFs and AgNCs (as reported here) upon simple UV exposure is being tested on different cloth materials (masks) to fight the COVID-19 pandemic
• An industry or market seeking such devices with augmented sensitivity could take forward the proposed methodology for utility in environmental safety and industrial applications
• A green approach for nano-engineering of silver nanoparticles and photonic sensor platforms that are of immense benefit for low- and middle-income countries, in resource-limited settings
• The mobile phone-based sensor platform presents a user-eco-friendly and economical detection compared to existing cost intensive spectrophotometers

Team

Sriram Rathnakumar, Seemesh Bhaskar, Aayush Rai, Darisi V. V. Saikumar, Naga Sai Visweswar Kambhampati, Venketesh Sivaramakrishnan and Sai Sathish Ramamurthy. Sri Sathya Sai Institute of Higher Learning, Prasanthi Nilayam, Puttaparthi, Anantapur, Andhra Pradesh 515134, India

Paper Published in: ACS Applied Nano Materials

Title: Plasmon-Coupled Silver Nanoparticles for Mobile Phone-Based Attomolar Sensing of Mercury Ions

Read Paper Here: https://pubs.acs.org/doi/10.1021/acsanm.1c01347