Food safety applications of surface-enhanced Raman Spectroscopy
Surface-enhanced Raman Spectroscopy (SERS) is a nuanced chemical technique that amplifies the Raman scattering of molecules by utilising plasmonic nanostructured materials. SERS operates as a powerful detection tool that allows for the structural fingerprinting of a molecule. The ultra-high sensitivity and selectivity of the process offer it a vast array of applications in surface and interface chemistry, nanotechnology, biology, biomedicine, food science, environmental analysis and other areas.
Dr J P Raja Pandiyan and his PhD scholar, Ms Arunima Jinachandran from the Department of Chemistry have been keenly involved in exploring the possibilities of SERS technology in food science and other fields. The safety and quality concerns related to food were the primary reasons that impelled them to step into this domain. Their article “Surface-enhanced Raman spectroscopy for food quality and safety monitoring” was published in the book Nanotechnology Applications for Food Safety and Quality Monitoring, published by Elsevier. The article was published in collaboration with Dr Selvaraju Kanagarajan from the Swedish University of Agricultural Sciences.
As an analytical technique, SERS possesses several advantages such as non-destructive, sensitive, and selective. In the chapter, the necessity, and applications of SERS in food science are elaborately discussed. They have also discussed all the possible food contaminants and how to identify them using SERS to ensure food quality. This book will serve as an enlightening read to research groups who are working on Raman, surface-enhanced Raman spectroscopy, analytical chemistry, and food quality analysis.
- Published in Chemistry-news, Departmental News, News, Research News
Comparing organic food preferences of American and Indian consumers
A paper titled “Organic food preferences: A comparison of American and Indian consumers” has been published by Prof Bharadhwaj Sivakumaran, Dean- SEAMS, SRM University-AP, Kirubaharan Boobalan (SSN College of Engineering), and Margaret Susairaj (Great Lakes Institute of Management, Chennai) in the journal Food Quality and Preference having an Impact Factor of 5.6.
This research tests a nomological model predicting organic food attitudes and purchase intentions in USA and India. Data were collected from India (n = 687) and the USA (n = 632) using Amazon M Turk and were analyzed using structural equation modelling and multi-group moderation technique. Results revealed that over and above attitude, subjective norm and perceived behavioural control, response efficacy and self-expressive benefits significantly affect consumers’ attitudes and purchase intentions toward organic food among American and Indian consumers. Findings reveal that response efficacy and attitude matter more in the USA while subjective norms and self-expressive benefits exert a greater influence in India. Therefore, marketers may reinforce belief-related elements while selling organic food products in the USA and societal-related elements while selling in India. Theoretically, this work adds to the Theory of Planned Behavior by adding self-expressive benefits and develops a common model for organic food across samples in USA and India.
- Published in Dean, Departmental News, News, Paari Current Happenings, Research News
Recovery of nutrients from wastewater
Water pollution continues to be one of the serious concerns facing the country. The ensuing scenario of eutrophication and harmful algal blooms has exacerbated the menace. This demands wholescale water management techniques to segregate the pollutants, retrieve useful nutrients, and treat the water effectively for sustainable use. Dr Karthik Rajendran and his PhD scholar, Mr Sarath Chandra, from the Department of Environment Science have published a paper discussing various nutrient recovery methods and their consequential outcomes. The research was done in collaboration with Dr Deepak Kumar from SUNY College of Environmental Science and Forestry, Syracuse, NY and Dr Richen Lin from Southeast University, Nanjing, China.
The article titled, “Nutrient recovery from wastewater in India: A perspective from mass and energy balance for a sustainable circular economy” was published in Bioresource Technology Reports (Q1 Journal), having an Impact Factor of 4.41. Their research investigates the possibilities of recovering Nitrogen (N) and Phosphorous (P) from wastewater in terms of technology, energy, and economic point of view. Excessive presence of Nitrogen and Phosphorous can result in eutrophication and algal blooming. These nutrients also pose a harmful threat to infrastructure. Nutrient recovery can mitigate these challenges and improve the quality of water.
Phosphorus is one of the limited resources available on earth and a key ingredient in fertilizer production. The recovery process also helps in transforming wastewater into resource pools that can efficiently churn out valuables that hold the key to a sustainable future. This will help reduce the imports of fertilizers and bring down the emissions to half in producing fertilizers. Their findings will also pave the way for making necessary policies to reduce water pollution and recover nutrients. As two-thirds of wastewater remains uncollected, they claim that effective treatment and water management practices can save around 800 crores per annum. Their future research plan also includes the experimental analysis of the nutrient recovery system.
Abstract of the Research
Wastewater (WW) is a potential source to recover N, and P, whereas, in India, it is scarcely explored. In this work, four different nutrient recovery methods were compared from a mass- and energy-balance perspective to understand the overall process flow. From 1000-m3 WW, chemical precipitation yielded 33.8 kg struvite, while micro-algae resulted in 299.1 kg (dry powder). Energy consumption was lowest for the fuel cells at 216.2 kWh/1000 m3, while microalgae used the highest energy at 943.3 kWh/1000 m3. Nonetheless, the cost-saving analysis showed that microalgae (78.6$/1000 m3) as a nutrient recovery choice, had higher savings than any other methods compared. For a country like India, where two-thirds of urban wastewater is untreated, wastewater-biorefinery options such as nutrient recovery hold the key to a sustainable circular economy.
- Published in Departmental News, ENVS News, News, Research News
Enhanced charge transport behaviour of protein-metal nanocluster hybrid
Proteins are the most vital life forms which maintain close coordination with almost living activities through their biological functions. Nevertheless, in most cases, proteins suffer from low charge (electron) transfer efficiency as they are mainly made of insulating organic molecules. The interdisciplinary research publication, of Dr Sabyasachi Mukhopadhyay and Dr Sabyasachi Chakrabortty from the Department of Physics & Department of Chemistry respectively, along with their PhD scholars: Ms Ashwini Nawade, Mr Kumar Babu Busi and Ms Kunchanapalli Ramya, envisions the molecular-level understanding of the charge transport behaviour of various protein-metal nanocluster hybrid.
The article titled ‘“Improved Charge Transport across Bovine Serum Albumin – Au Nanoclusters’ Hybrid Molecular Junction” was featured in the prestigious Q1 journal ACS Omega (IF: 3.512), published by the ‘American Chemical Society’. They successfully incorporated Gold Nanoclusters inside the protein backbone leading to an increase in their conductivity. This will provide new avenues for the rational design of bioelectronic devices with optimized features. The BSA-Au cluster has been a promising model for bioelectronic functionalities. With an increase in their current carrying capacity, they can be used for many more applications, especially as the interface between tissue and organ in biocompatible devices. The research team is also planning to work with various protein dopants to understand their charge transport mechanism. These studies will help in using the protein for various applications mainly in bioimplants or biosensors for drug testing and diagnostics purposes.
Abstract of the Research
Proteins, a highly complex substance, have been the essential element in the living organism where various applications are envisioned due to their biocompatible nature. Apart from protein’s biological functions, contemporary research mainly focuses on their evolving potential associated with nanoscale electronics. Here, we report one type of chemical doping process in model protein molecules (BSA) to modulate its electrical conductivity by incorporating metal (Gold) nanoclusters on the surface or within it. The as-synthesized Au NCs incorporated inside the BSA (Au 1 to Au 6) were optically well characterized with UV-Vis, time-resolved photoluminescence (TRPL), X-ray photon spectroscopy, and high-resolution transmission electron microscopy techniques. The PL quantum yield for Au 1 is 6.8% whereas Au 6 is 0.03%. In addition, the electrical measurements showed ~10-fold enhancement of conductivity in Au 6 where maximum loading of Au NCs was predicted inside the protein matrix. We observed a dynamic behaviour in the electrical conduction of such protein-nanocluster films, which could have real-time applications in preparing biocompatible electronic devices.
- Published in Chemistry-news, Departmental News, News, Physics News, Research News