Usha K Aravind

• PhD chemistry
• Professor at Cochin University of Science and Technology

Indoor environments are particularly vulnerable to microplastics (MPs) and associated copollutants due to limited air circulation and particulate matter accumulation. Continuous monitoring is essential to evaluate exposure levels and health risks. We propose using indoor spider webs as passive monitors for MPs and their copollutants. MPs were found...

In this article, maintaining the quality and commercial properties of mineral fertilizers during repeated transshipment and long-term transportation is one of the important issues. The purpose of the research work is to study the structure of granules of complex mixed fertilizers, as well as to find and develop methods for improving it at the produ...

This article provides information on the synthesis of esterified derivatives of hydrolyzed polyacrylonitrile (EPAN) based on the polymer waste “Nitron” for use as an encapsulating reagent. The elemental and structural compositions of potassium humate and the organic polymer were determined using a scanning electron microscope (Jeol JSM-6490l V) and...

This study focused on monitoring phosphorus (P) concentrations in the water of the Ramsar site, Lake Vembanad, with a special focus on the mouths of the river bodies draining into the lake, a known hotspot for eutrophication. Four phosphorus fractions—total reactive phosphorus (TRP), total acid hydrolysable phosphorus (TAHP), total organic phosphor...

Phosphorus (P) concentration in rivers and lakes receives greater attention due to its significance in contributing to eutrophication. This study aimed at profiling phosphorus species in Vembanad lake (Ramsar site) and its adjoining rivers. Four phosphorus fractions (total reactive phosphorus (TRP), total acid hydrolysable phosphorus (TAHP), total...

Pectin is a soluble dietary fiber with several health benefits, such as antibacterial, antioxidant, gastrointestinal-protective, and anticancer properties. Pectin is becoming an important class of materials owing to their inherent structural and functional properties such as biodegradability, binding potential, self-assembly, high nutritional value...

This article a synthesis of humic acid with the obtaining of potassium humate based on coal waste from the Lenger deposit. Accumulated industrial waste heavily pollutes the environment and has a direct impact on all living things. The accumulation of waste in landfills increases the pollution level of the atmosphere, soil, groundwater, and surface...

Indoor environments act as significant reservoirs for a wide range of potentially harmful substances, with microplastics (MPs) gaining increased attention in recent years. This study offers valuable insights into the role of MPs as both source and sink for hazardous contaminants within indoor environments. The analytical techniques employed encompa...

The degradation of recalcitrant organic pollutants by sulphate radical (SO4•−) represents one of the most recent developments in oxidation-based water treatment. In most cases, persulfate (PS) acts as a precursor of sulphate radicals. This study employed ultrasound-activated PS to generate reactive species, facilitating the degradation of bisphenol...

The molecular basis of protein unfolding on exposure to the widely used herbicide, Glyphosate (GLY), its metabolite aminomethylphosphonic acid (AMPA), and the commercial formulation Roundup have been probed using human and bovine serum albumins (HSA and BSA). Protein solutions were exposed to chemical stress at set experimental conditions. The stud...

To date, accumulated industrial waste creates serious environmental problems in the regions. Therefore, their processing in order to obtain valuable products is an urgent task. As a result of the reduction electric smelting of phosphorite raw materials in the Novo-Dzhambul phosphorus plant, about 150-160 kg of cuttrel dust is formed per 1 ton of ye...

Advanced oxidation processes (AOPs) hold great promise in the removal of organic contaminants. Reactive oxygen species (ROS) produced in AOPs react with target pollutants to initially form several intermediate compounds that finally undergo complete mineralization. Such observations are reported, especially for laboratory-scale experiments performe...

The degradation of pollutants by a non-radical pathway involving singlet oxygen (1O2) is a hot topic in persulfate-based advanced water treatment processes (PS-AOPs). The selective reaction of 1O2 with organic pollutants resulting the evolution of different intermediate products. While these products are identified by mass spectrometry (MS) techniq...

The investigations of protein adsorption and release on interfaces aid in the elucidation of the protein-surface interaction mechanism, which has several applications in the biomedical area. The spectro-kinetic and morphological analysis of the release of lysozyme (Lyz) from chitosan/polystyrene sulphonate (CHI/PSS) multilayer immobilized at pHs 10...

This article provides information on the technology of obtaining chelated organomineral micro fertilizers based on phosphorus and coal production waste to increase crop yields. The obtained chelated organomineral micro-fertilizers are involved in the structure formation of the soil and eliminate the deficiency of nutrients and increase productivity...

The processes of membrane separation and concentration belong to the category of critical technologies for obtaining and processing structural and functional materials for desalination of water. The prospects and advantages of polyamides membranes are determined based on the analysis of the kinetics of membrane separation, the polyamides membrane h...

Atmospheric aerosols, produced as a consequence of different anthropogenic and natural processes, impart significant control over the global energy budget, climate, and human–environmental health. Their size varies across the nano–micrometer scale. Based on their origin, they may be classified into primary or secondary aerosols. Biomass burning, in...

Elimination of polycyclic aromatic hydrocarbons (PAHs) from aquatic environment is extremely important, as they are identified pollutants. The oxidative degradation of two model PAHs, namely 3‐hydroxy‐2‐naphthoic acid (3HNA) and 6‐hydroxy‐2‐naphthoic acid (6HNA), collectively represented as HNAs in this report, were investigated by utilizing a comb...

Elimination of organic contaminants of emerging concern (CECs) from precious environmental resources is an important process for reducing adverse effects to living species. Advanced oxidation processes (AOPs) have already been adopted by many researchers to detoxify several CECs. However, hydroxyl (OH) radical reaction, the primary degradation mech...

The elimination of organic contaminants from natural resources is extremely important to ensure their (re-)usability. In this report, the degradation of a model pharmaceutical compound, theophylline, is compared between natural and laboratory-controlled environments. While the concentration of H2O2 variably affected the degradation efficiency (appr...

Pharmaceutical compounds, released into the aquatic system through normal human usage and industrial activities, are generally biologically active and persistent in the environment. This study investigated the active degradation of a pharmaceutical compound, isoniazid (INH), in an aqueous medium using sonochemical method. Sonochemical degradation w...

A detailed investigation on the sonochemical degradation of DEET (N,N-diethyl-m-toluamide), a widely used broad spectrum insect repellant and an ubiquitous contaminant of emerging concern (CEC) in aquatic environments, was conducted in aqueous medium. The degradation followed a pseudo-first-order kinetics. The effects of pH, inorganic anions, organ...

The successful evolution of an effective drug depends on its pharmacokinetics, efficiency and safety and these in turn depend on the drug-target/drug-carrier protein binding. This work, deals with the interaction of a pyridine derivative, 2-hydroxy-5-(4-methoxyphenyl)-6-phenylpyridine 3-carbonitrile (HDN) with serum albumins at physiological condit...

Implosion–demolitions are used to bring down tall-storied structures in urban centers. This technique was employed to raze four residential complexes constructed against the law in India’s tropical coastal city (Kochi). The demolitions were carried out in an ecologically fragile area. It is the first of a kind experiment in India and the highest st...

Graywater reuse is one of the important concepts in attaining water sustainability. A major challenge in this area is to realize various components present in graywater. The present study involves the identification of the chemical components of graywater collected from three different environments and to investigate the efficiency of removal of so...

The major share of the total radiation exposure in human beings is from natural sources and hence its measurement is vital to the fundamental understanding of radiation exposure. Natural background gamma radiation of 72 outdoor sites and 32 indoor sites covering all 14 districts of Kerala, a southern state of India, was monitored over a period of t...

Copper is an essential trace element for human biology where its metal dyshomeostasis accounts for an increased level of serum copper, which accelerates protein aggregation. Protein aggregation is a notable feature for many neurodegenerative disorders. Herein, we report an experimental study using two model proteins, bovine serum albumin (BSA) and...

Hydroxyl radical induced oxidation of carbaryl has been studied using steady state photolysis followed by high-resolution mass spectrometry (LC-Q-TOF-MS), pulse radiolysis, and theoretical (DFT) calculations. The reaction of ●OH with carbaryl resulted in a number of hydroxylated adduct radicals (λmax - 330 nm and 390 nm; k2 - 1.2 × 10¹⁰ dm³ mol⁻¹ s...

There is a rise in concern across the globe over the contaminants of emerging concerns (CECs) such as pharmaceuticals, personal care products (PCPs), UV stabilizers, surfactants, endocrine disrupting compounds (EDCs), etc. In the present study, we have identified some compounds belonging to the classes of pharmaceuticals, PCPs, and EDCs in the wate...

Extensive use of surfactants in numerous fields resulted in their discharge into various environmental compartments including soil, sediment, and water. Alcohol ethoxysulfates (AES) together with alcohol ethoxylates (AE), alkyl sulfates (AS), and linear alkyl benzene sulfonates (LAS) find wide variety of applications in consumer products including...

An analysis on the presence of uranium in drinking water sources of five districts in Kerala, Southern India has been carried out. 830 Samples from different sources during pre and post-monsoon seasons were subjected to the analysis for uranium and 11 other water quality parameters. The concentration of uranium was found to be varying from <0.5–12....

Indoor dust is an important matrix that exposes humans to a broad spectrum of chemicals. The information on the occurrence of contaminants of emerging concern (CECs), their metabolites, and re-emerging contaminants in indoor dust is rather limited. As the indoor environment is exposed to various chemicals from personal care products, furniture, bui...

The use of bottled water is increasing every day even after the reported presence of microbial and other contaminants. The present study analyzed bromate in bottled water samples collected from four major cities in Kerala, India. It was found that about 40% of the samples contain bromate with a maximum concentration of 9.68 μg/L with an average of...

Heavy metal based toxicity has a direct relation with the perturbation of protein structure. We have investigated the progressive unfolding of ovalbumin, in the presence of increasing concentration mercury (0–6.25 μM) using different spectroscopic techniques. Formation of amorphous aggregate has been observed at the physiological pH. Initial additi...

A low saline backwater canal, mainly utilized for domestic and agricultural purposes, has been analyzed for the possible presence of organic micropollutants (OMP) and their potential removal was explored by multilayered microfiltration membranes. The qualitative as well as quantitative analysis were carried out for a span of one year using the tech...

Pharmaceutical compounds released into the aquatic environment are famed for their persistence in the environment. Advanced oxidation processes (AOPs) are considered as the most efficient technology for the complete degradation and mineralisation of organic pollutants. This study describes an investigation on the degradation of the active pharmaceu...

The study of atmospheric particulate matter has a high significance in realising the pollution status of any region. In this study, we have investigated the nature of PM2.5 aerosol samples over a semi-urban atmosphere located in the south-western part of India, using a low volume air sampler for 5 days (120 h). The analyses of the particles were ca...

Protein-ligand binding studies have gained considerable attention owing to its application in biomedical research. The present study discusses the application of spectroscopic and theoretical methods to probe the interaction between a model ligand, 1, 3-diphenylisobenzofuran (DPBF) and bovine serum albumin (BSA). The quenching of the intrinsic fluo...

The intriguing resemblances of amyloid fibrils and spider silk in protein aggregation diseases have instigated the exploration of identical structural features if any in their oligomeric pathways. The serpin group protein, ovalbumin, on defolding in HgCl2 shares commonness to the micellar pathway of spidroins for their aggregation in response to a...

Air quality disturbance zones of the Greater Cochin region (Kerala, India) for the years 2014, 2015, 2016 and 2017 along with air quality assessment and dispersion modelling using in situ measurements and mathematical models, have been investigated in this report. Landsat-8 satellite with OLI and TIRS sensors on board were used for the analysis. Th...

Surfaces of commercially available polyamide membranes were modified by polyelectrolyte monolayer by dip coating method. The formation of monolayered membranes was confirmed by spectroscopic and microscopic methods. The membrane performance is evaluated for the removal of beta blockers (β-blockers) from aqueous solution and resulted in nearly compl...

Degradation of benzenesulfonic acid (BSA), the simplest aromatic sulfonic acid with extreme industrial importantance, by sonochemically generated hydroxyl radical (OH) have been thoroughly investigated. A reasonable reduction (∼50%) in the total organic carbon (TOC) was achieved only after prolonged irradiation (∼275 min, 350 kHz) of ultrasound, al...

Zinc oxide nanocomposites with Li and Ag doping were synthesized and were characterized by scanning electron microscope (SEM), X-ray diffraction (XRD), diffused reflectance spectroscopy (DRS), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS) and time of flight secondary ion mass spectroscopy (ToF-SIMS). A peak shift was observed in XRD di...

In this study, PSS doped CaCO3 microparticles were used as sacrificial templates for the fabrication of hollow polyelectrolyte microcapsules. The lysozyme loading studies of two systems - chitosan/polymethacrylic acid (CHI/PMA) and chitosan/polystyrene sulfonate (CHI/PSS) microcapsules were carried out. The influences of feed and deposition pH on l...

Harvesting of rainwater is a widely practiced, cost - effective and efficient method to meet the increasing demand for water in the contemporary world. The quality evaluation of harvested rainwater is having great importance. The present study site, Achinakom, is a low lying area (Below MSL). Rainwater harvesting is the most suitable option for the...

Electrospray ionization-collisionally induced dissociation (ESI-CID) pathways of nitenpyram (NP), a neonicotinoid insecticide, have been investigated. An extensive radical initiated-mechanism was observed which varied according to the nature of the solvent. Two pathways- the NO2● and ●OH radical eliminations- were observed and rationalized using DF...

Environmental context Perchlorate from rocket fuel plants or firework manufacturing units can seriously contaminate drinking water. We developed a separation skin on a microfiltration membrane and on sand that can remove perchlorate from water in the presence of competing ions. This method is suitable for a domestic water purification unit selectiv...

The analysis of urinary nucleosides is becoming a very good tool in the diagnosis of diseases like AIDS and cancer and consequently the identification of modified nucleosides using mass spectrometry is an area of utmost importance. In this context, there is a high relevance in the understanding of the mechanism of collisionally induced dissociation...

Environmental context Ranitidine, a widely prescribed antiulcer drug commonly found in surface waters, has been identified as an emerging contaminant due to its toxicity and the enhanced toxicity displayed by its transformation products. Mechanisms for the formation of ranitidine transformation products and their degradation pathways induced by UV...

Layer by layer (LbL) assembly can be regarded as an emerging technology for the separation of organic micro-pollutants from water. Direct assembly of polyelectrolytes (PEs) under LbL mode on natural support material is rare. Here we report the integration of LbL to one of the most resourceful support materials that might have an enduring impact on...

The mechanistic aspects of hydroxyl ([rad]OH) and sulfate radical (SO4[rad]−) induced oxidation of diphenylmethanol (DPM) in aqueous medium has been explored using a combined experimental and theoretical approach. [rad]OH initiates the generation of hydroxycyclohexadienyl-type radicals (i) upon reaction with DPM (λmax = 330 nm; k2 = (1.44 ± 0.08) ×...

The removal of toxic heavy metals (Cd, Pb and Hg) from aqueous solution has been attempted in two different modes by using macromolecular assisted and immobilized multilayered modified polyether sulfone membranes (PES). PES membrane was modified with chitosan (CHI) and poly (styrene sulfonate) (PSS) using layer by layer (LbL) method. Humic acid (HA...

The present study describes the monitoring of some of the major classes of surfactants in water. The separation, identification, and the quantitative estimation of the compounds were achieved using LC-Q-ToF-MS. The analyses revealed the presence of variety of surfactants including linear alkylbenzene sulfonate (LAS), alcohol ethoxysulfates (AES), a...

Triphenylmethane (TPM) dyes are an important category of dyes with a variety of industrial applications and consequently, these are found in the aquatic environment at relatively higher concentrations. Here, we report the degradation of two important TPM dyes (para rosaniline (PRA) and ethyl violet (EV)) in an aqueous medium by ultrasound which is...

The presence of emerging contaminants (ECs) in different aquatic systems may contribute to hazardous effects on aquatic organisms and subsequently on human health. In the present work, liquid chromatography coupled to a quadrupole time of flight mass spectrometer (LC-Q-ToF-MS) was used to identify and quantify a series of ECs in Periyar River in Al...

Frustum shaped clay ceramic water filters are being manufactured by the potters of the Thar Desert in India for household use. The clay composite consists of a homogeneous mixture of equal volume of clay and sawdust. A low-cost manual press, to form the clay composite into frustum shape, is developed by the present authors. This article elaborates...

The application of antibiotics to livestock has become a serious global concern. The increasing demand for animal protein leads to a greater use of antibiotics in livestock production. This is contributing to a global scale-up in antibiotic consumption. This chapter analyses the use of antibiotics in animals and the emergence of antibiotics as a cl...

Pollution and fate of pollutants in polar region are important topics of investigation in the last several decades. We have analysed sediment samples from Kongsfjorden and Krossfjorden, two sites from Arctic region, and detected a number of emerging contaminants (ECs) using high-resolution mass spectrometry connected to UPLC (LC-Q-ToF-MS). Out of t...

The present report profiles the complete ultrasound mediated transformation products of a DNA nucleoside, 2’-deoxycytidine (dCyd), the second in this series, using high resolution mass spectrometry (UPLC−Q-ToF-MS). The compound, dCyd was subjected to sonolysis under four different frequencies (200, 350, 620 and 1000 kHz) at a power density of 24.5...

The heterogeneous catalytic degradation of a model azo dye, acid red 1 (AR1), initiated by zero valent iron nanoparticles (ZVINP), and its synergic effect with ultrasound (US) have been investigated in the present study. The treatment of AR1 using ZVINP at pH 3 showed maximum efficiency in terms of colour removal (53.0%) and mineralization (48.5% T...

A detailed investigation on the photocatalytic degradation and mineralization of lignocaine, a local anesthetic, under UV irradiation has been carried out in this study. The dose of TiO2 was optimized initially and was found as 250 mg L⁻¹ for the degradation of 2 mg L⁻¹ concentration of lignocaine. The scavenging experiment using isopropanol and me...

Microfiltration (MF) membranes with chitosan/polystyrenesulfonate (CHI/PSS) functional layer coated surface can act as a barrier against emerging contaminants (ECs) in water under low pressure. One (one bilayer) or two functional layers are enough for the removal of lidocaine (LD, 100%) and ibuprofen (IBU, >75%). The effect of various ions, surfact...

The emergence of issues related to environment from ECs is a topic under serious discussions worldwide in recent years. Indian scenario is not an exception as it is tremendously growing in its rate of production and consumption of compounds belongs to ECs categories. However, a comprehensive documentation on the occurrence of ECs and consequent ARG...

The sonochemical transformation of para-aminosalicylic acid (PAS), a widely used antibiotic and an identified Emerging Pollutant (EP) under the class of Pharmaceuticals and Personal Care Products (PPCPs), have been investigated in aqueous medium. Ultrasound having frequency of 350 kHz and power of 80W was utilized for the degradation of PAS. A comp...

Ultrasound is known to degrade organic compounds by pyrolysis and by the reaction of free radicals. In this work, sonolytic degradation of an identified water pollutant, coomassie brilliant blue (CBB), has been carried out in pure water as well as in river water. In the case of pure water, 90 % degradation was obtained after 30 min of sonication (3...

Reductive and oxidative degradation of amaranth dye using zero valent iron nanoparticles (ZVINP) has been investigated. Effect of various reaction parameters such as the iron dosage, stirring speed, and influence of pH were studied, and an optimum condition deduced. The ideal operational conditions were 1.5–2.5 g/L of ZVINP, 15–30 min of reaction t...

Off-white water pots have had sustained traditional acceptance for a long period of time in Jodhpur compared to red colored water pots imported from the neighboring Gujarat state. Both types of pots hold 20 liters of potable water. The fluorescence spectroscopy reveals dominance of silica, alumina and iron oxide in red pots from Gujarat whereas off...

Implications of sulfidized Fe⁰ (nFe/FeS) for the abatement of pollutants of various categories are widely established. In this study, degradation of one of the major organic pollutants, benzoic acid (BA), has been performed using persulfate activated with nFe/FeS. Complete degradation of BA and its transformed product, hydroxybenzoic acid, was obse...

BACKGROUND As amino acids provide a green feedstock for the synthesis of chemicals, their isolation through low energy route sounds encouraging. RESULTS The changes in the permeation characteristics of microfiltration (MF) membranes with the deposition of a few bilayers of chitosan (CHI) and polystyrene sulfonate (PSS) for the low pressure filtrat...

Water pollution by pharmaceutically active compounds is an emerging issue. Toxicological studies reveal that pharmaceuticals are indeed toxic for living organisms. The lack of suitable treatment technology for the complete removal of pharmaceuticals is therefore a major challenge. Advanced oxidation processes are emerging removal techniques that ha...

Mechanistic aspects of diphenhydramine (DPH) oxidation induced by hydroxyl (•OH) and sulfate (SO4•−) radicals have been explored in detail by pulse radiolysis technique and high resolution mass spectrometry (HRMS). The transient absorption spectrum along with HRMS analysis undoubtedly established the non-position selective hydroxylation of DPH by •...

Ultrasound is extensively used in medical field for a number of applications including targeted killing of cancer cells. DNA is one of the most susceptible entities in any kind of free radical induced reactions in living systems. In the present work, the transformation of thymidine (dT) induced by ultrasound (US) was investigated using high resolut...