Ranjana Das

Involvement of process parameters and various modes of application of TiO2 nanoparticles in heterogeneous photocatalysis of pharmaceutical wastes – a short review

In recent years, the occurrence of persistent organic compounds in industrial as well as municipal effluents is becoming a serious threat to the environment. The pharmaceutical compounds present along with those organics have a detrimental effect on our environment. Among various well established wastewater treatment technologies, advanced oxidation processes (AOPs) using TiO2 nanoparticles have shown promising results against various organic wastewater pollutants. This study represents an in-depth review of applications of TiO2 in the treatment of various pharmaceutical wastes and the effects of associated process controlling parameters. It also highlights aspects of different application techniques of TiO2 nanoparticles and the involvement of reaction kinetics in photocatalytic degradation.

Development of a mathematical model to predict different parameters during pharmaceutical wastewater treatment using TiO2 coated membrane

The aim of present study is to develop a mathematical model to understand the photomineralization process for an antiseptic drug component, chlorhexidine digluconate using catalytic membrane. Overall process was executed in a photo reactor with immobilized TiO2 nanoparticles on the membrane surface, which gives the better recovery and reuse of the catalyst. To assess the overall process performance, a mathematical model has been developed for prediction of substrate concentration in the permeate stream and the theoretical build-up of the polarized layer in case of a membrane coated with TiO2 nanoparticles. In the developed mathematical model, the governing partial differential equation was solved with the help of initial boundary condition over the concentration boundary layer and Kozeny-Carmen equation. In this model the simultaneous change in the active surface area and the polarized layer thickness with the change in substrate concentration in the boundary layer was incorporated to enhance the accuracy of the model. The resulting non-linear partial differential equation, coupled with other non-linear ordinary differential equation is solved using Runga Kutta fourth order method. Average deviation between theoretical results and the experimental data generated in this study was found to remain within ±5% and precision level was maintained at 0.01%.

Application of ANFIS model to optimise the photocatalytic degradation of chlorhexidine digluconate

The degradation of chlorhexidine digluconate (CHD) has been investigated using TiO2 suspension under UV irradiation with variation of pH, catalyst loading and substrate concentration within the range of 4.0–10.5, 0.1–0.4 g L−1 and 0.5–1.5 g L−1, respectively. The molecules of CHD have been adsorbed on TiO2 nano particles and degraded under UV irradiation. The influence of reaction parameters has been studied and reasons behind those have been correspondingly established. The molecular weights of by-products have been identified after photocatalytic degradation using mass spectroscopy. During the optimization of the process parameters, subtractive clustering fuzzy inference system has been employed to generate the optimum fuzzy rule base sets. A stable estimation technique has been attained by applying hybrid learning algorithm. Moreover, the performance and accuracy of the developed model has been tested using distinct test data set randomly selected from the experimental domain. The effects of different inherent parameters of subtractive clustering have also been studied and among them only squash factor is found to be the most important one for the present study. ANFIS has thus proved to be a congenial tool for the optimization of process parameters of the photocatalytic reaction discussed here.

Enzymatic hydrolysis of native granular starches by a new β-amylase from peanut (Arachis hypogaea)

The present work describes efficient hydrolysis of native starch by a novel β-amylase from peanut (Arachis hypogaea). The Dextrose Equivalent value, which is a measure of starch hydrolysis, for potato and corn starch increased significantly by 40% and 10%, respectively, releasing maltose. Scanning electron microscopy revealed that enzymatic corrosion occurred mainly at the surface of starch granules, leaving broken granules to smaller particles at later stage of digestion. Further, X-ray analysis and Fourier transform infrared spectroscopy displayed the loss of ordered structure in the enzyme degraded starches. These results described the pattern of hydrolysis. Since the action of already known plant β-amylases (sweet potato and soybean) on native starch granule is not very effective and requires gelatinization for maltose production, β-amylase from peanut could be a useful alternative in the present endeavor. It would potentially save time and money arising from gelatinization and lead to improvements in industrial maltose production.

Hydrogel nanocomposite for controlled drug release

Abstract Nanocomposite hydrogels (NC gels) is a typical material which is hydrated polymeric networks furnished with nanomaterials, having typical characteristics like superior strength and higher elasticity compared to conventional hydrogels. The polymeric nanocomposite network is designed based on both natural and synthetic polymers. By proper tuning of the interactions within nanoparticles and polymeric chains, inherent properties of hydrogels (chemical, physical, and biological) can be designed. An appropriate combination of polymeric material (organic part) and inorganic (clay) material imparts improved swelling/de-swelling properties, biological properties, physical, chemical, and electrical properties to hydrogel those are not achievable from single component system. Novel type hydrogels have been designed by incorporating wide range of materials such as polymeric, ceramic, and/or metallic nanomaterials, carbon-based to grasp unique features, like stimulus-sensitivity which are essential criterion of drug delivery systems. Nanocomposite hydrogels have excellent combination of mechanical properties specifically excellent compression properties, swelling (and de-swelling) properties which distinguish conventional hydrogels. This review aims to portray the basics of nanocomposite hydrogel, its application profile, major shortcomings, and its future developments.

Engineered Nanomaterial in Environmental Industry

Abstract Environmental industry (EI) is a sector dealing with broad based environmental protection and associated services. An EI consists of activities which produce goods and services to measure, prevent, limit, and minimize or correct environmental damage to water, air, and soil, as well as problems related to waste, noise, and ecosystems. Engineered nanomaterials are an amazing boon of the research activities in nanotechnology which have the potential applications in revolutionizing many aspects of human lives. Engineered nanomaterials typically offer unique properties that are arising due to their dimensions. In recent time research activities have been aligned to exploit the unique features of nanomaterial to improve lifestyles as well as for environmental remediation. This article presents details about the characteristic features of the engineered nanomaterials from diverse groups, like semiconductor metal oxide, carbon-based nanomaterials, and magnetic nanomaterials, and their application in environmental remediation and environmental protection.

Application of nanobioceramics in bone tissue engineering

These days nanoscale biomaterials are of great interest due to their unlimited potential to improve human health as hard tissue engineering materials. Tissue engineering combines the disciplines of materials science and engineering with biology and involves the application of the materials to induce tissue regeneration. The overall purpose of tissue engineering is to control the cellular interaction with synthetic engineered materials for the treatment of structurally degenerated organs in the human body. In bone tissue engineering (BTE), metals and polymers typically remain separated from adjoining bone structures causing a mismatch in functional properties between bone tissue and artificial implants inducing several clinical plights, such as, wound infection, morbidity, and desorption of adjacent bone. Bioceramics are used as reasonable alternatives with enhanced biocompatibility and capacity to form a strong chemical bond to adjacent bone. This chapter abridges the fundamentals of BTE, current state of the techniques, the recent developments of bioceramics, and approaches used to enhance bone regeneration.

Hydrogel: Polymeric Smart Material in Drug Delivery

A ‘biomaterial’, recognizes some materials for biomedical applications like replacement of living system and wound stressing. ‘Biomaterials’ includes different compounds from diverse origins, like polymers, metals, ceramics and composites. Along with conventional natural polymers (polysaccharides, proteins), synthetic and biodegradable polymers like Polyvinyl alcohol, Polyvinylpyrrolidone, Polyetheleneglycol, Polylactic acid, Polyhydroxy acid are promisingly used in drug delivery, tissue engineering, biomedical sensing, skin grafting and medical adhesives. ‘Hydrogel’ a new generation biodegradable polymer typically used for pharmaceutical and medical purposes. Hydrogels are coined as super absorbent with significant function in health care, especially in wound treatment and protection. Unique characteristics features like enhanced hydrophilicity, biocompatibility, zero-toxicity and biodegradability along with soft and rubbery consistency, low interfacial tension and ‘self-healing’ properties make them compatible with living tissues. Hydrogels have been widely investigated as the carrier for drug delivery systems owing to their unusual characteristics like swelling in aqueous medium, pH and temperature sensitivity, or sensitivity towards other stimuli. Hydrogels being biocompatible materials have been recognized to function as drug protectors, especially for peptides and proteins, from in-vivo environment. In present context, development of ‘in situ’ forming systems for various biomedical applications, including drug delivery, cell encapsulation, and tissue repair are emerging. Among several typical hydrogel synthesis approaches like, solvent exchange, UV-irradiation, ionic cross-linkage, pH change, and temperature modulation, the ‘thermosensitive’ approach is advantageous since it does not require use of any organic solvents, co-polymerization agents and externally applied trigger for gelation. This review presents an overview to the advances in hydrogel based drug delivery system with some reconstructive features in the biomedical applications.

Processing Sesame Seeds and Bioactive Fractions

Abstract This review intends to highlight the techniques of value addition to sesame seed. As well as its utilization as an edible oil source, it can also be utilized to isolate several valuable components for specialty applications. This review covers utilization of sesame seed hull as a source of antioxidants. This hull was also reported as a source of cellulose which was used to prepare the nano-cellulose particle for better functionality. Sesame meal was also taken into consideration as a source of sesame lignan glycosides, phenolic antioxidants, and protein based bioactives like sesame peptides. This review also covers the probable utilization pattern for each bioactive fraction and the future scope of the bioactives for better exploitation. Preparation of the nano-sized sesame glucosides with improved adsorption and transport properties and prospects of nano-sesame protein have been included in this review as part of sustainable product developments.