CERES :: Browsing by Author "Thakur, Vijay Kumar"

Browsing by Author "Thakur, Vijay Kumar"

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Open Access
4D printing of smart polymer nanocomposites: integrating graphene and acrylate based shape memory polymers
(MDPI, 2021-10-24) Chowdhury, Jaydeep; Anirudh, Premnath Vijay; Karunakaran, Chandrasekaran; Rajmohan, Vasudevan; Mathew, Arun Tom; Koziol, Krzysztof K. K.; Alsanie, Walaa F.; Kannan, Chidambaram; Balan, Arunachalam S. S.; Thakur, Vijay Kumar
The ever-increasing demand for materials to have superior properties and satisfy functions in the field of soft robotics and beyond has resulted in the advent of the new field of four-dimensional (4D) printing. The ability of these materials to respond to various stimuli inspires novel applications and opens several research possibilities. In this work, we report on the 4D printing of one such Shape Memory Polymer (SMP) tBA-co-DEGDA (tert-Butyl Acrylate with diethylene glycol diacrylate). The novelty lies in establishing the relationship between the various characteristic properties (tensile stress, surface roughness, recovery time, strain fixity, and glass transition temperature) concerning the fact that the print parameters of the laser pulse frequency and print speed are governed in the micro-stereolithography (Micro SLA) method. It is found that the sample printed with a speed of 90 mm/s and 110 pulses/s possessed the best batch of properties, with shape fixity percentages of about 86.3% and recovery times as low as 6.95 s. The samples built using the optimal parameters are further subjected to the addition of graphene nanoparticles, which further enhances all the mechanical and surface properties. It has been observed that the addition of 0.3 wt.% of graphene nanoparticles provides the best results.
Open Access
Analysis and advanced characterization of municipal solid waste vermicompost maturity for a green environment
(Elsevier, 2019-12-03) Srivastava, Vaibhav; Goel, Gaurav; Thakur, Vijay Kumar; Singh, Rajeev Pratap; Ferreira de Araujo, Ademir Sergio; Singh, Pooja
Rapid demographic expansion along with increasing urbanization has aggravated the problem of solid waste management. Therefore, scientists are seeking waste management methods that are eco-friendly, cost effective and produce immediate results. In the developing world, municipal solid waste (MSW) contains mostly organic substances, therefore vermicomposting could be a better and cost-effective option for waste management. In this study, vermicomposting of organic portion of MSW with cow dung (additive) was performed using Eisenia fetida. The results showed significant (p < 0.001) decline in pH (13.17%), TOC (21.70%), C: N (62.53%) and C: P (57.66%) ratios, whilst total N (108.9%), P (84.89%) and K (21.85%) content increased (p < 0.001) in matured vermicompost. Different enzymatic activities declined during termination phase of vermicomposting experiment with maximum decrease of 41.72 (p = 0.002) and 39.56% (p = 0.001) in protease and β-glucosidase, respectively. FT-IR, TGA, DSC and SEM studies suggested that final vermicompost was more stabilized as compared to initial waste mixture, characterized by reduced levels of aliphatic materials, carbohydrates and increase in aromatic groups possibly due to biosynthesis of humic substances. Both, the conventional (physicochemical and enzyme activity) and advanced techniques depict maturity and stability of the ready vermicompost. However, FT-IR, TGA, DSC and SEM were proved to be more promising, fast and reliable techniques over conventional analyses.
Open Access
Arabinose as an overlooked sugar for microbial bioproduction of chemical building blocks
(Taylor and Francis, 2023-11-06) Kumar, Vinod; Agrawal, Deepti; Bommareddy, Rajesh Reddy; Islam, M. Ahsanul; Jacob, Samuel; Balan, Venkatesh; Singh, Vijai; Thakur, Vijay Kumar; Navani, Naveen Kumar; Scrutton, Nigel S.
The circular economy is anticipated to bring a disruptive transformation in manufacturing technologies. Robust and industrial scalable microbial strains that can simultaneously assimilate and valorize multiple carbon substrates are highly desirable, as waste bioresources contain substantial amounts of renewable and fermentable carbon, which is diverse. Lignocellulosic biomass (LCB) is identified as an inexhaustible and alternative resource to reduce global dependence on oil. Glucose, xylose, and arabinose are the major monomeric sugars in LCB. However, primary research has focused on the use of glucose. On the other hand, the valorization of pentose sugars, xylose, and arabinose, has been mainly overlooked, despite possible assimilation by vast microbial communities. The present review highlights the research efforts that have explicitly proven the suitability of arabinose as the starting feedstock for producing various chemical building blocks via biological routes. It begins by analyzing the availability of various arabinose-rich biorenewable sources that can serve as potential feedstocks for biorefineries. The subsequent section outlines the current understanding of arabinose metabolism, biochemical routes prevalent in prokaryotic and eukaryotic systems, and possible products that can be derived from this sugar. Further, currently, exemplar products from arabinose, including arabitol, 2,3-butanediol, 1,2,3-butanetriol, ethanol, lactic acid, and xylitol are discussed, which have been produced by native and non-native microbial strains using metabolic engineering and genome editing tools. The final section deals with the challenges and obstacles associated with arabinose-based production, followed by concluding remarks and prospects.
Open Access
Batch and fed-batch ethanol fermentation of cheese-whey powder with mixed cultures of different yeasts
(MDPI, 2019-11-26) Farkas, Csilla; Rezessy-Szabó, Judit M.; Gupta, Vijai Kumar; Bujna, Erika; Pham, Tuan M.; Pásztor-Huszár, Klára; Friedrich, László; Bhat, Rajeev; Thakur, Vijay Kumar; Nguyen, Quang D.
Eight yeast strains of Lachancea thermotolerans, Kluyveromyces marxianus, and Kluyveromyces waltii have been tested for their ability to ferment lactose into ethanol in mashes containing 10% (w/v) cheese whey powder (CWP). The K. marxianus NCAIM Y00963 achieved 3.5% (v/v) ethanol concentration at 96–120 h of fermentation. The ethanol production by the selected lactose-positive strains and the well-known ethanologenic Saccharomyces cerevisiae (Levuline Fb) in mixed culture was also investigated at different CWP concentrations and inoculation techniques in batch mode. The mixed culture in an equal ratio (1:1) of cell counts of K. marxianus and S. serevisiae showed an increase in lactose conversion rate. The two yeast strains in a ratio of 3:1 (three-quarters of K. marxianus and a quarter of S. cerevisiae in a total of 4.5 × 1010 cells) resulted in 72.33% efficiency of lactose bioconversion and 7.6% (v/v) ethanol production at 17.5% (w/v) of CWP concentration. In the repeated inoculation process, with the addition of three-quarter part of 3:1 ratio of mixed culture (3.3 × 1010 cells of K. marxianus) into 150 mL CWP mash at initiation and the rest quarter part (1.2 × 1010 cells of S. cerevisiae) at 24 h, 8.86% (v/v) ethanol content with 87.5% efficiency of lactose conversion was reached. Both the ethanol concentration and efficiency of bioconversion were increased to 10.34% (v/v) and 92%, respectively, by combination with fed-batch fermentation technology. Our results can serve a very good basis for the development of industrial technology for the utilization of cheese whey.
Open Access
Bio-based reactive diluents as sustainable replacements for styrene in MAESO resin.
(Royal Society of Chemistry, 2018-04-12) Zhang, Yuehong; Li, Yuzhan; Thakur, Vijay Kumar; Wang, Liwei; Gu, Jiyou; Gao, Zhenhua; Fan, Bo; Wu, Qiong; Kessler, Michael R.
Four different biorenewable methacrylated/acrylated monomers, namely, methacrylated fatty acid (MFA), methacrylated eugenol (ME), isobornyl methacrylate (IM), and isobornyl acrylate (IA) were employed as reactive diluents (RDs) to replace styrene (St) in a maleinated acrylated epoxidized soybean oil (MAESO) resin to produce bio-based thermosetting resins using free radical polymerization. The curing kinetics, gelation times, double bond conversions, thermal–mechanical properties, and thermal stabilities of MAESO-RD resin systems were characterized using DSC, rheometer, FT-IR, DMA, and TGA. The results indicate that all four RD monomers possess high bio-based carbon content (BBC) ranging from 63.2 to 76.9% and low volatilities (less than 7 wt% loss after being held isothermally at 30 °C for 5 h). Moreover, the viscosity of the MAESO-RD systems can be tailored to acceptable levels to fit the requirements for liquid molding techniques. Because of the introduction of RDs to the MAESO resin, the reaction mixtures showed an improved reactivity and an accelerated reaction rate. FT-IR results showed that almost all the C[double bond, length as m-dash]C double bonds within MAESO-RD systems were converted. The glass transition temperatures (Tg) of the MAESO-RDs ranged from 44.8 to 100.8 °C, thus extending the range of application. More importantly, the Tg of MAESO-ME resin (98.1 °C) was comparable to that of MAESO-St resin (100.8 °C). Overall, this work provided four potential RDs candidates to completely replace styrene in the MAESO resin, with the ME monomer being the most promising one.
Open Access
Biomimetic polymer reactor: design and modulation of novel tandem catalysts.
(Cranfield University, 2021-09) Wei, Wenjing; Chianella, Iva; Thakur, Vijay Kumar; Koziol, Krzysztof
Tandem catalysis can perform multi-step catalytic reactions in one-pot sequentially, which not only improves the efficiency of reactions significantly, but also decreases time, energy and the amounts of reagents needed. However, as there is always more than one active site (catalyst) in tandem reactors, it is critical to separate different sites and ensure each step is conducted individually. Moreover, it is often challenging to control the whole reaction processes due to the complexity of the systems. In this research, several bio-inspired catalytic reactors were proposed and developed to address the two challenges of site separation and smart control of tandem catalysis. First of all, the goal of sites separation has been achieved in this work through an enzyme-inspired molecularly imprinted polymer reactor MIP-Au-NP-BNPC and a core-shell structure catalytic nanoreactor AMPS@AM-Ag. Two molecularly imprinted cavities were created in MIP-Au-NP-BNPC. The different channels of the two catalytic sites in the reactor enabled different catalytic reactions to occur in different regions, resulting in the process of tandem reactions. As a result of the radial distribution of catalytic sites and mass transfer, the core-shell structure of AMPS@AM-Ag enabled the nanoreactor to perform different catalytic processes sequentially. Hence, the nanoreactor demonstrated the ability to conduct tandem catalysis with successful site separation. Then a biomimetic switch was introduced into the reactor to achieve the smart control of the catalytic process. Firstly, a new type of catalytic reactor consisting of a three-layer mussel-inspired polymer, MIP-AgPRS, was developed. The smart switchable layer composed of mussel-inspired self-healing copolymer was prepared between two MIP layers. This middle smart layer was able to react to different temperatures, permitting either simple or tandem reactions by closing and opening the access of the intermediate products. Secondly, a bilayer polymer reactor, DPR, composed of two different temperature-sensitive polymer layers was prepared. The two functional layers were not only able to respond to different specific temperatures, but each also contained different catalytic sites. Because of the two different phase transition processes of the two layers, the polymer reactor demonstrated to be able to perform simple/tandem catalysis in different temperature regions. As a result, this new type of bilayer polymer reactor was capable of achieving smart control of the tandem reactions. Finally, a three-layer switchable polymer reactor, PRS, with two MIP layers and a PNIPAM-PAM switchable layer in the middle was prepared. In an aqueous environment, when the temperature was low (lower than 47 °C), it exhibited an open access (hydrophilic condition), while when the temperature was high (higher than 47 °C), it became closed (hydrophobic condition). Furthermore, a comonomer (AM) was introduced in the middle layer with different ratios to adjust the responsive temperature range, enabling a more comprehensive range of practical uses. Therefore, a fast responsive and stable polymer reactor with self- controlled catalytic property was obtained. By preparing different types of new catalytic reactors, the research carried out here has shown the ability to achieve a smart control of the tandem catalysis while separating the catalytic sites effectively. Therefore, this study has highlighted new solutions to address the challenges present in tandem catalysis and has provided novel inspiration on how to exploit functional polymers while performing complicated catalytic reactions.
Open Access
Biomimetically inspired highly homogeneous hydrophilization of graphene with poly (L-DOPA): toward electroconductive coatings from water-processable paints
(American Chemical Society, 2022-05-10) Kuziel, Anna; Dzido, Grzegorz; Jędrysiak, Rafał G.; Kolanowska, Anna; Jóźwiak, Bertrand; Beunat, Juliette; Korczeniewski, Emil; Zięba, Monika; Terzyk, Artur P.; Yahya, Noorhana; Thakur, Vijay Kumar; Koziol, Krzysztof K. K.; Boncel, Sławomir
Water-based processing of graphene─typically considered as physicochemically incompatible with water in the macroscale─emerges as the key challenge among the central postulates of green nanotechnology. These problematic concerns are derived from the complex nature of graphene in the family of sp2-carbon nanoallotropes. Indeed, nanomaterials hidden under the common “graphene” signboard are very rich in morphological and physicochemical variants. In this work, inspired by the adhesion chemistry of mussel biomaterials, we have synthesized novel, water-processable graphene–polylevodopa (PDOPA) hybrids. Graphene and PDOPA were covalently amalgamated via the “growth-from” polymerization of l-DOPA (l-3,4-dihydroxyphenylalanine) monomer in air, yielding homogeneously PDOPA-coated (23 wt %) (of thickness 10–20 nm) hydrophilic flakes. The hybrids formed >1 year stable and water-processable aqueous dispersions and further conveniently processable paints of viscosity 0.4 Pa·s at 20 s–1 and a low yield stress τ0 up to 0.12 Pa, hence exhibiting long shelf-life stability and lacking sagging after application. Demonstrating their applicability, we have found them as surfactant-like nanoparticles stabilizing the larger, pristine graphene agglomerates in water in the optimized graphene/graphene–PDOPA weight ratio of 9:1. These characteristics enabled the manufacture of conveniently paintable coatings of low surface resistivity of 1.9 kΩ sq–1 (0.21 Ω·m) which, in turn, emerge as potentially applicable in textronics, radar-absorbing materials, or electromagnetic interference shielding.
Open Access
Biopolymers for biomedical and pharmaceutical applications: Recent advances and overview of alginate electrospinning
(MDPI, 2019-03-10) Wróblewska-Krepsztul, Jolanta; Rydzkowski, Tomasz; Michalska-Pożoga, Iwona; Thakur, Vijay Kumar
Innovative solutions using biopolymer-based materials made of several constituents seems to be particularly attractive for packaging in biomedical and pharmaceutical applications. In this direction, some progress has been made in extending use of the electrospinning process towards fiber formation based on biopolymers and organic compounds for the preparation of novel packaging materials. Electrospinning can be used to create nanofiber mats characterized by high purity of the material, which can be used to create active and modern biomedical and pharmaceutical packaging. Intelligent medical and biomedical packaging with the use of polymers is a broadly and rapidly growing field of interest for industries and academia. Among various polymers, alginate has found many applications in the food sector, biomedicine, and packaging. For example, in drug delivery systems, a mesh made of nanofibres produced by the electrospinning method is highly desired. Electrospinning for biomedicine is based on the use of biopolymers and natural substances, along with the combination of drugs (such as naproxen, sulfikoxazol) and essential oils with antibacterial properties (such as tocopherol, eugenol). This is a striking method due to the ability of producing nanoscale materials and structures of exceptional quality, allowing the substances to be encapsulated and the drugs/biologically active substances placed on polymer nanofibers. So, in this article we briefly summarize the recent advances on electrospinning of biopolymers with particular emphasis on usage of Alginate for biomedical and pharmaceutical applications.
Open Access
Bioproduction of succinic acid from xylose by engineered Yarrowia lipolytica without pH control
(BMC - Springer Nature, 2020-06-27) Prabhu, Ashish Ashok; Ledesma-Amaro, Rodrigo; Lin, Carol Sze Ki; Coulon, Frederic; Thakur, Vijay Kumar; Kumar, Vinod
Background Xylose is the most prevalent sugar available in hemicellulose fraction of lignocellulosic biomass (LCB) and of great interest for the green economy. Unfortunately, most of the cell factories cannot inherently metabolize xylose as sole carbon source. Yarrowia lipolytica is a non-conventional yeast that produces industrially important metabolites. The yeast is able to metabolize a large variety of substrates including both hydrophilic and hydrophobic carbon sources. However, Y. lipolytica lacks effective metabolic pathway for xylose uptake and only scarce information is available on utilization of xylose. For the economica feasibility of LCB-based biorefineries, effective utilization of both pentose and hexose sugars is obligatory. Results In the present study, succinic acid (SA) production from xylose by Y. lipolytica was examined. To this end, Y. lipolytica PSA02004 strain was engineered by overexpressing pentose pathway cassette comprising xylose reductase (XR), xylitol dehydrogenase (XDH) and xylulose kinase (XK) gene. The recombinant strain exhibited a robust growth on xylose as sole carbon source and produced substantial amount of SA. The inhibition of cell growth and SA formation was observed above 60 g/L xylose concentration. The batch cultivation of the recombinant strain in a bioreactor resulted in a maximum biomass concentration of 7.3 g/L and SA titer of 11.2 g/L with the yield of 0.19 g/g. Similar results in terms of cell growth and SA production were obtained with xylose-rich hydrolysate derived from sugarcane bagasse. The fed-batch fermentation yielded biomass concentration of 11.8 g/L (OD600: 56.1) and SA titer of 22.3 g/L with a gradual decrease in pH below 4.0. Acetic acid was obtained as a main by-product in all the fermentations. Conclusion The recombinant strain displayed potential for bioconversion of xylose to SA. Further, this study provided a new insight on conversion of lignocellulosic biomass into value-added products. To the best of our knowledge, this is the first study on SA production by Y. lipolytica using xylose as a sole carbon source.
Open Access
Carbon nanotube embedded adhesives for real-time monitoring of adhesion failure in high performance adhesively bonded joints
(Springer Nature, 2020-10-08) Bregar, Tadej; An, Donglan; Gharavian, Somayeh; Burda, Marek; Durazo-Cardenas, Isidro; Thakur, Vijay Kumar; Ayre, David; Słoma, Marcin; Hardiman, Mark; McCarthy, Conor; Nezhad, Hamed Yazdani
Carbon nanotubes (CNTs) embedded polymers are of increasing interest to scientific and industrial communities for multi-functional applications. In this article, CNTs have been introduced to high-strength epoxy adhesive for enabling in-situ strain sensing in adhesively bonded aluminium-to-aluminium single-lap joints to accurately indicate the onset and propagation of adhesion failure to the evolution of piezo-resistivity in varying mechanical loads. The CNT modified adhesive in bonded joints and the CNT modified adhesive alone have been tested under monothonic and cyclic tensile loads up to ultimate failure. The changes in the piezo-resistivity induced by the CNTs have been monitored in situ with respect to loading. A novel interpretation method has been developed for progressive, instantaneous adhesion failure estimation under cyclic tensile stresses from a resistivity baseline. The method indicates that the in-situ resistivity changes and the rate of the changes with strain, i.e. sensitivity, strongly correlate with the adhesion failure progression, irrespective of the CNT dispersion quality. Moreover, the effect of bond thickness on the evolution of piezo-resistivity and adhesion failure have been studied. It was observed that relatively thin adhesive bonds (0.18mm thickness), possessing higher CNT contact points than thick bonds (0.43mm thicknes), provide 100 times higher sensitivity to varying cyclic loads
Open Access
Carbon quantum dot supported semiconductor photocatalysts for efficient degradation of organic pollutants in water: a review
(Elsevier, 2019-04-25) Sharma, Sheetal; Dutta, Vishal; Singh, Pardeep; Raizada, Pankaj; Rahmani-Sani, Abolfazl; Hosseini-Bandegharaei, Ahmad; Thakur, Vijay Kumar
Semiconductor photocatalyst mediated advanced oxidation processes are regarded as one of the most efficient technologies to mitigate organic pollutants in water. However, poor activity under visible light and the recombination of photogenerated electron and hole pairs hinder large scale applicability of semiconductor photocatalysts for water purification. The modification of semiconductor photocatalysts with carbon quantum dots (CQDs) is of high importance due to low toxicity, aqueous stability, enhanced surface area, economic feasibility, good biocompatibility and chemical inertness of CQDs. In this review, we highlight strategies to improve the activity of conventional semiconductor photocatalysts via coupling with CQDs. The enhanced photocatalytic activity of CQD modified narrow and wide band gap photocatalysts is due mainly to up-conversion photoluminescence (UPCL) and the electron reservoir properties of CQDs, while in the case of Z-scheme photocatalysts CQDs act as an electron mediator. Finally, a conclusive outlook and suggested research directions are provided to address challenges such as the inadequate separation of photoinduced charge carriers.
Open Access
Carbon-based polymer nanocomposite for high-performance energy storage applications
(MDPI, 2020-02-26) Siwal, Samarjeet Singh; Zhang, Qibo; Devi, Nishu; Thakur, Vijay Kumar
In recent years, numerous discoveries and investigations have been remarked for the development of carbon-based polymer nanocomposites. Carbon-based materials and their composites hold encouraging employment in a broad array of fields, for example, energy storage devices, fuel cells, membranes sensors, actuators, and electromagnetic shielding. Carbon and its derivatives exhibit some remarkable features such as high conductivity, high surface area, excellent chemical endurance, and good mechanical durability. On the other hand, characteristics such as docility, lower price, and high environmental resistance are some of the unique properties of conducting polymers (CPs). To enhance the properties and performance, polymeric electrode materials can be modified suitably by metal oxides and carbon materials resulting in a composite that helps in the collection and accumulation of charges due to large surface area. The carbon-polymer nanocomposites assist in overcoming the difficulties arising in achieving the high performance of polymeric compounds and deliver high-performance composites that can be used in electrochemical energy storage devices. Carbon-based polymer nanocomposites have both advantages and disadvantages, so in this review, attempts are made to understand their synergistic behavior and resulting performance. The three electrochemical energy storage systems and the type of electrode materials used for them have been studied here in this article and some aspects for example morphology, exterior area, temperature, and approaches have been observed to influence the activity of electrochemical methods. This review article evaluates and compiles reported data to present a significant and extensive summary of the state of the art.
Open Access
Cellulose acetate membranes functionalized with resveratrol by covalent immobilization for improved osseointegration
(Elsevier, 2018-11-13) Pandele, A. M.; Neacsu, P.; Cimpean, A.; Staras, A. I.; Miculescu, F.; Iordache, A.; Voicu, S. I.; Thakur, Vijay Kumar; Toader, O. D.
Covalent immobilization of resveratrol onto cellulose acetate polymeric membranes used as coating on a Mg-1Ca-0.2Mn-0.6Zr alloy is presented for potential application in the improvement of osseointegration processes. For this purpose, cellulose acetate membrane is hydrolysed in the presence of potassium hydroxide, followed by covalent immobilization of aminopropyl triethoxy silane. Resveratrol was immobilized onto membranes using glutaraldehyde as linker. The newly synthesised functional membranes were thoroughly characterized for their structural characteristics determination employing X-ray photoelectron spectroscopy (XPS), infrared spectroscopy (FT-IR), Raman spectroscopy, thermogravimetric analysis (TGA/DTG) and scanning electron microscopy (SEM) techniques. Subsequently, in vitro cellular tests were performed for evaluating the cytotoxicity biocompatibility of synthesized materials and also the osseointegration potential of obtained derivatised membrane material. It was demonstrated that both polymeric membranes support viability and proliferation of the pre-osteoblastic MC3T3-E1 cells, thus providing a good protection against the potential harmful effects of the compounds released from coated alloys. Furthermore, cellulose acetate membrane functionalized with resveratrol exhibits a significant increase in alkaline phosphatase activity and extracellular matrix mineralization, suggesting its suitability to function as an implant surface coating for guided bone regeneration.
Open Access
Cellulose-based smart materials: Novel synthesis techniques, properties, and applications in energy storage and conversion devices
(Wiley, 2024-05-25) Bishnoi, Pariksha; Siwal, Samarjeet Singh; Kumar, Vinod; Thakur, Vijay Kumar
There has been a significant scope toward the cutting-edge investigations in hierarchical carbon nanostructured electrodes originating from cellulosic materials, such as cellulose nanofibers, available from natural cellulose and bacterial cellulose. Elements of energy storage systems (ESSs) are typically established upon inorganic/metal mixtures, carbonaceous implications, and petroleum-derived hydrocarbon chemicals. However, these conventional substances may need help fulfilling the ever-increasing needs of ESSs. Nanocellulose has grown significantly as an impressive 1D element due to its natural availability, eco-friendliness, recyclability, structural identity, simple transformation, and dimensional durability. Here, in this review article, we have discussed the role and overview of cellulose-based hydrogels in ESSs. Additionally, the extraction sources and solvents used for dissolution have been discussed in detail. Finally, the properties (such as self-healing, transparency, strength and swelling behavior), and applications (such as flexible batteries, fuel cells, solar cells, flexible supercapacitors and carbon-based derived from cellulose) in energy storage devices and conclusion with existing challenges have been updated with recent findings.
Open Access
Cellulosic biomass-based sustainable hydrogels for wastewater remediation: Chemistry and prospective
(Elsevier, 2021-10-03) Thakur, Sourbh; Verma, Ankit; Kumar, Vinod; Yang, Xiao Jin; Krishnamurthy, Satheesh; Coulon, Frederic; Thakur, Vijay Kumar
Despite several technological improvements and achievements, wastewater treatment remains a serious issue internationally. Toxins in wastewater pose a significant threat to human health if left untreated. Due to macro-porous structure and different surface functionalization, cellulose biomass-based hydrogel is the most traditional adsorbent for removing harmful ions from wastewater. Recently, the introduction of several new cellulose derived materials have demonstrated their competitiveness in the removal of harmful ions. Numerous exceptional qualities better define this promising material, including high mechanical strength, large surface area and chemical inertness. This paper discusses the development status, preparation and modification methods of cellulose composites created by various materials (graphene, fly ash, graphene oxide and bentonite) which evaluates the research development and existing challenges in water treatment.
Open Access
Chemistry, structures, and advanced applications of nanocomposites from biorenewable resources
(American Chemical Society, 2020-07-30) Ates, Burhan; Koytepe, Suleyman; Ulu, Ahmet; Gurses, Canbolat; Thakur, Vijay Kumar
Researchers have recently focused on the advancement of new materials from biorenewable and sustainable sources because of great concerns about the environment, waste accumulation and destruction, and the inevitable depletion of fossil resources. Biorenewable materials have been extensively used as a matrix or reinforcement in many applications. In the development of innovative methods and materials, composites offer important advantages because of their excellent properties such as ease of fabrication, higher mechanical properties, high thermal stability, and many more. Especially, nanocomposites (obtained by using biorenewable sources) have significant advantages when compared to conventional composites. Nanocomposites have been utilized in many applications including food, biomedical, electroanalysis, energy storage, wastewater treatment, automotive, etc. This comprehensive review provides chemistry, structures, advanced applications, and recent developments about nanocomposites obtained from biorenewable sources.
Open Access
Chitosan-based advanced materials for docetaxel and paclitaxel delivery: Recent advances and future directions in cancer theranostics
(Elsevier, 2019-12-20) Ashrafizadeh, Milad; Ahmadi, Zahra; Mohamadi, Neda; Zarrabi, Ali; Abasi, Sara; Dehghannoudeh, Gholamreza; Tamaddondoust, Rosette N.; Khanbabaei, Hashem; Mohammadinejad, Reza; Thakur, Vijay Kumar
Paclitaxel (PTX) and docetaxel (DTX) are key members of taxanes with high anti-tumor activity against various cancer cells. These chemotherapeutic agents suffer from a number of drawbacks and it seems that low solubility in water is the most important one. Although much effort has been made in improving the bioavailability of PTX and DTX, the low bioavailability and minimal accumulation at tumor sites are still the challenges faced in PTX and DTX therapy. As a consequence, bio-based nanoparticles (NPs) have attracted much attention due to unique properties. Among them, chitosan (CS) is of interest due to its great biocompatibility. CS is a positively charged polysaccharide with the capability of interaction with negatively charged biomolecules. Besides, it can be processed into the sheet, micro/nano-particles, scaffold, and is dissolvable in mildly acidic pH similar to the pH of the tumor microenvironment. Keeping in mind the different applications of CS in the preparation of nanocarriers for delivery of PTX and DTX, in the present review, we demonstrate that how CS functionalized-nanocarriers and CS modification can be beneficial in enhancing the bioavailability of PTX and DTX, targeted delivery at tumor site, image-guided delivery and co-delivery with other anti-tumor drugs or genes.
Open Access
Deep eutectic solvents toward the detection and extraction of neurotransmitters: an emerging paradigm for biomedical applications
(American Chemical Society, 2023-05-17) Kaur, Harjot; Siwal, Samarjeet Singh; Kumar, Vinod; Thakur, Vijay Kumar
Neurotransmitters (NTs), the chemical messengers crucial for the proper functioning of the human brain, have some specific concentration within the human physiological system. Any fluctuations in their concentration may cause several neuronal diseases and disorders. Therefore, the requirement for fast and effective diagnosis to regulate and manage human cerebral diseases or conditions is surging swiftly. NTs can be extracted from natural products. The researchers have developed new protocols to improve the sensors’ sensing ability and eco-friendly nature. Deep eutectic solvents (DESs) have gained popularity as “green solvents” in sustainable chemistry. DESs provide a greater range of a potential window that helps in the enhanced electrocatalytic performance of the sensor and more inertness which helps in the corrosion protection of electrodes, ultimately giving better sensitivity and durability to the system. In addition, DESs provide facile electrodeposition of different materials on working electrodes, which is a prime prerequisite in electrocatalytic sensors. Here, in this review, the application of DESs as green solvents in detecting and extracting NTs is described in detail for the first time. We cover the available online articles up to December 2022 for the extraction and monitoring of NTs. Finally, we have concluded the topic with future prospects in this field.
Open Access
Differential susceptibility of catheter biomaterials to biofilm-associated infections and their remedy by drug-encapsulated Eudragit RL100 nanoparticles
(MDPI, 2019-10-15) Pandey, Vivek Kumar; Srivastava, Kumar Rohit; Ajmal, Gufran; Thakur, Vijay Kumar; Gupta, Vijai Kumar; Upadhyay, Siddh Nath; Mishra, Pradeep Kumar
Biofilms are the cause of major bacteriological infections in patients. The complex architecture of Escherichia coli (E. coli) biofilm attached to the surface of catheters has been studied and found to depend on the biomaterial’s surface properties. The SEM micrographs and water contact angle analysis have revealed that the nature of the surface a ects the growth and extent of E. coli biofilm formation. In vitro studies have revealed that the Gram-negative E. coli adherence to implanted biomaterials takes place in accordance with hydrophobicity, i.e., latex > silicone > polyurethane > stainless steel. Permanent removal of E. coli biofilm requires 50 to 200 times more gentamicin sulfate (G-S) than the minimum inhibitory concentration (MIC) to remove 90% of E. coli biofilm (MBIC90). Here, in vitro eradication of biofilm-associated infection on biomaterials has been done by Eudragit RL100 encapsulated gentamicin sulfate (E-G-S) nanoparticle of range 140 nm. It is 10–20 times more e ective against E. coli biofilm-associated infections eradication than normal unentrapped G-S. Thus, Eudragit RL100 mediated drug delivery system provides a promising way to reduce the cost of treatment with a higher drug therapeutic index.
Open Access
Editorial overview: From linear to circular economies: The importance and application of recycling and reuse
(Elsevier, 2018-09-19) Gupta, Raju Kumar; Thakur, Vijay Kumar; Matharu, Avtar Singh