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Abstract: Cancer stem cells (CSCs) are transformed forms of normal stem cells within heterogeneous mixture of cancer cells. These are mainly responsible for the recurrence of cancer after treatment because of their ability to develop resistance against chemo and radiotherapy due to various factors such as activation of signalling pathways important for self-renewal, DNA repair capacity, microenvironment and expression of ABC transporters. Targeting these mechanisms as potential factors can eliminate CSCs, which eventually decreases cancer recurrence. This review focuses on the characteristics of CSCs, their role in the development of resistance to chemotherapy and radiotherapy along with the therapeutic potential targets for successful elimination of CSC population.

A novel nano-magnetite supported N-heterocyclic carbene-gold complex with pendant ferrocenyl group has been prepared by using a multi-step procedure. The complex displayed significantly higher anticancer activity against the MCF-7 breast cancer cell line with IC50 = 32.38 µg/mL as compared with standard drug 5-fluorouracil (IC50 = 25.29 µg/mL) in the MTT assay. The in-ovo antiangiogenic activity of the complex using chicken chorioallantoic membrane assay showed significant decrease in secondary blood vessels indicating that it is efficient angiogenesis inhibitor. The hyperthermia studies of the complex revealed a significant specific absorption rate (SAR) value of 246.974 Wg-1 with therapeutic temperature of 46.8 oC.

This paper presents an organic memristive device based on the soft and quasi-liquid trypsin biomaterial. Accordingly, trypsin is isolated from the bovine pancreas and deposited on a conducting fluorine-doped tin oxide (FTO) substrate. The current–voltage (I–V) measurements of the trypsin/FTO device show a hysteresis loop at multiple frequencies and voltages. The results demonstrate that the current and resistance of the device can be modulated by altering the frequency and magnitude of the applied signal, suggesting the feasibility of this material for brain-inspired computing devices. The hysteresis area of the device increases in proportion to the frequency of the signal, signifying the inverse-memristive phenomenon. The time-domain flux, time-domain charge, and charge-flux properties are calculated from the experimental I–V data to demonstrate the memristive nature of the trypsin hydrogel. Interestingly, the trypsin hydrogel memristive device mimics bio-synaptic properties such as potentiation–depression and four complex spike-time-dependent plasticity learning rules. Electrochemical studies are performed to understand the electrochemical kinetics of the device. A possible switching mechanism is illustrated to show the memristive effect of the trypsin hydrogel. The results of the present investigation suggest that trypsin can be a possible biomaterial to develop an electronic synaptic device for neuromorphic computing applications.

Glycation of proteins is often considered as a method to improve their functional properties for promising applications in wound healing. Furthermore, a marked increase in percentage of radical scavenging activity of the conjugates makes it an effective antioxidant synthetic strategy. A simple conjugation process was employed to develop bovine serum albumin–dextran conjugates (BSA–dextran) using Maillard reaction. Higher electrophoretic mobility and surface charge in the prepared conjugates was observed in native PAGE electrophoresis and zeta potential. Moreover, the fluorescence, FTIR and Raman analysis of the BSA–dextran conjugates shows significant shift in the fluorescence and wavelength as a consequence of conjugate formation. In vitro wound healing assay showed increased cell proliferation and migration effect. These finding suggests that BSA–dextran conjugate could open up a new practical way for exploration in the area of wound healing.

Objective: The present study was aimed at the biological synthesis of magnetic iron nanoparticles by using the plant extract of Tridax procumbens and also to study their antimicrobial property against gram-negative bacteria (Escherichia coli). Methods: The synthesis of magnetic iron nanoparticles was carried out by the co-precipitation method using biological methods like plant extract as reducing agent and capping agents are biocompatible and non-hazardous. These nanoparticles were characterized by UV-Visible spectroscopy, XRD (X-Ray Diffraction), and SEM (Scanning Electron Microscope). As well as antibacterial activity of the nanoparticles was carried out by agar well diffusion method and Most Probable Number (MPN) method against gram-negative E. coli (Escherichia coli) bacteria. Results: The average crystallite size of Magnetic Nanoparticles (MNPs) was found to be 72 nm by X-ray diffraction. The optical absorption band at wavelengths of 240 nm and 402 nm was obtained from the UV Visible spectrum. Spherical shape morphology was observed in SEM studies. The antibacterial assay clearly expressed that E. coli showed a maximum zone of inhibition (15±0.15 mm) at 2 mg/ml and 1 mg/ml concentration was found for Magnetic Nanoparticles. In the Most Probable Number (MPN) test it is seen that the bacterial count is reduced after adding synthesized NPs into the water sample. Conclusion: The results of the present study conclude that the Magnetic Nanoparticles synthesized using Tridax procumbens leaf extracts is found to be stable and show good antibacterial activity against gram-negative (Escherichia coli) bacteria.

‘Bioinks’ are important tools for the fabrication of artificial living-tissue constructs that are able to mimic all properties of native tissues via 3D bioprinting technologies. Bioinks are most commonly made by incorporating live cells of interest within a natural or synthetic biocompatible polymeric matrix. In oncology research, the ability to recreate atumor microenvironment(TME) using by 3D bioprinting constitutes a promising approach for drug development, screening, andin vitrocancer modeling. Here, we review the different types of bioink used for 3D bioprinting, with a focus on its application in cancer management. In addition, we consider the fabrication of bioink using customized materials/cells and their properties in the field of cancer drug discovery.

The present work demonstrates the non-volatile resistive switching behavior of cellulose-gelatine microcomposite fibers (CGMFs). The CGMFs were synthesized using the electrospinning technique and used as a switching layer for a resistive memory device. The morphological study reveals that the switching layer was composed of good quality of microcomposite fibers and possesses cross-link like morphology. The functional groups present in the switching layer were confirmed by Fourier-transform infrared spectroscopy technique. The CGMFs based device shows the bipolar resistive switching effect and requires low SET (+ 1.33 V) and RESET (− 1.42 V) voltages for the operation. The charge-magnetic flux relation of the device was calculated and memristive device like properties were observed from the results. The charge driving capability of the device was found to be ~ 1.3 × 10−2 C, which is sufficient to get the good resistive switching property. The non-volatile resistive switching behavior of the CGMFs based device suggested that the device has good performance in terms of endurance (500 cycles) and retention (2000 s). The uniformity and reliability of the device were confirmed by statistical calculations (standard deviation and coefficient of variation). The conduction model fitting results suggested that the space charge limited current (SCLC) and Ohmic conduction mechanisms were responsible for device operation during the high resistance state (HRS) and low resistance state (LRS), respectively. A possible resistive switching mechanism is presented by considering the formation and rupture of Ag conductive filament under the influence of external voltage.

Wastewater discharged by some industries under uncontrolled and unsuitable conditions is leading to significant environmental concern. Dyes are one of the major constituents in wastewater. Industrial dyes are stable, toxic and also considered potentially carcinogenic. Their release into the environment can lead to serious environmental and health problems. Hence, it is important to treat dye wastewater before it gets discharged in outer environment. In this study, Iron oxide nanoparticles (IONPs) were synthesized by co-precipitation method. The iron oxide nanoparticles were then surface functionalized by the Glycolipid biosurfactant, Rhamnolipid (RL) which was produced by Pseudomonas aeruginosa ATCC 9027. The surface functionalization of iron oxide nanoparticles by biologically obtained Rhamnolipid reduces toxicity and at the same time makes the material biodegradable and highly selective due to presence of some reactive functional groups on the surface. IONPs and Rhamnolipid functionalized iron oxide nanoparticles (RL@IONPs) were characterized by UV–VIS spectroscopy, X-ray diffraction (XRD) and Scanning Electron Microscopy (SEM). Photo catalytic activity of IONPs and RL@IONPs was studied for methyl violet dye. In addition to this, sodium dodecyl sulphate (SDS) was used as an efficient adsorbent and the dye removal efficiency with SDS as a binding agent was found to be 92.72%. The high adsorption and dye removal efficiency of RL@IONPs establishes its potential in detoxifying wastewater streams from hazardous dyes.

The biomaterial-based memristive devices are attracting massive attention due to their biocompatibility, biodegradability, reusability, and eco-friendly nature properties. The present chapter intends to review the basic concepts and state of the art in biomaterial-based resistive switching devices. Based on our experimental results, the chapter, in particular, focuses on the synthesis, characterization, and nonvolatile memory performance of DNA and melanin memristive devices. The developed DNA based organic nonvolatile memory device was found to demonstrate bipolar resistive switching characteristics and operate at very low resistive switching voltage (±0.5 V). Moreover, double-valued charge-magnetic flux characteristics suggested the memristive like nature of the DNA-based device. The DNA memristive device shows good endurance (200 cycles) property and retained data up to 103 seconds with good uniformity in the temporal distribution. In the case of melanin, devices were developed using three different bottom electrodes (FTO, TiN, and flexible PET) and their resistive switching performance was compared. The results suggested that the resistive switching properties of the Al/melanin/FTO-based device are comparatively better than other devices. The endurance of the Al/melanin/FTO-based device was stable over 103 cycles and data can be retained for a long time ( 3 × 10 3 s). The conduction and resistive switching mechanisms of both devices are also presented.

Iron oxide photocatalysts are applicable to produce clean renewable energy resources. Iron oxide structures turn out as one of the promising candidates after the formation of oxygen vacancies on the surface and in bulk structures. Oxygen-deficient iron oxide nanostructures can solve global issues such as environmental pollution and energy supply. We have summarized oxygen-deficient α-Fe2O3 and Fe3O4 nanostructures, their preparation methods and properties on the basis of dimensions and different photocatalytic applications such as photoelectrochemical water splitting for hydrogen production, photocatalytic degradation and atmospheric CO2 reduction. In the end, we have highlighted the challenges and opportunities to provide perspective for different problems associated with α-Fe2O3 and Fe3O4 nanostructures.

Glycation of proteins is often considered as a method to improve their functional properties for promising applications in wound healing. Furthermore, a marked increase in percentage of radical scavenging activity of the conjugates makes it an effective antioxidant synthetic strategy. A simple conjugation process was employed to develop bovine serum albumin-dextran conjugates (BSA-dextran) using Maillard reaction. Higher electrophoretic mobility and surface charge in the prepared conjugates was observed in native PAGE electrophoresis and zeta potential. Moreover, the fluorescence, FTIR and Raman analysis of the BSA-dextran conjugates shows significant shift in the fluorescence and wavelength as a consequence of conjugate formation.

SARS-CoV-2 has devastated the world with its rapid spread and fatality. The researchers across the globe are struggling hard to search a drug to treat this infection. Understanding the time constraint, the best approach is to study clinically approved drugs for control of this deadly pandemic of COVID 19. The repurposing of such drugs can be supported with the study of molecular interactions to enhance the possibility of application. The present work is a molecular docking study of proteins responsible for viral propagation namely 3Clpro, Nsp10/16, Spike protein, SARS protein receptor binding domain, Nsp 9 viral single strand binding protein and viral helicase. The protein through virus enters the host cell-human angiotensin-converting enzyme 2 (ACE2) receptor, is also used as a target for molecular docking. The docking was done with most discussed drugs for SARS-CoV-2 like Ritonavir, Lopinavir, Remdesivir, Chloroquine, Hydroxychloroquine (HCQ), routine antiviral drugs like Oseltamivir and Ribavirin. In addition, small molecules with anti-inflammatory actions like Mycophenolic acid (MPA), Pemirolast, Isoniazid and Eriodictyol were also tested. The generated data confirms the potential of Ritonavir, Lopinavir and Remdesivir as a therapeutic candidate against SARS-CoV-2. It is observed that Eriodictyol binds to almost all selected target proteins with good binding energy, suggesting its importance in treatment of COVID 19. Molecular interactions of Ritonavir, Lopinavir and Remdesivir against SARS-CoV-2 proteins enhanced their potential as a candidate drug for treatment of COVID-19. Eriodictyol had emerged as a new repurposing drug that can be used in COVID-19.

The use of nanotechnology in medicine has a potential impact on human health in terms of its prevention, diagnosis, and treatment of life-threatening diseases, such as cancer. Nanomedicine provides detection of cancer and enhances its treatment efficiency by minimizing the diverse effect associated with the standard therapies. It deals with delivering of various drugs via various mechanisms such as active and passive targeting and triggered release of encapsulated content by solubilization and reduces the risk of systemic side effects. Several experimental challenges need to be conquered to address from bench to besides. Herein, we discussed the clinical translations of nanomedicines its development and commercialization in terms of various drugs. Furthermore, the issues related to development of materials is explored in detail including large-scale manufacturing, biological challenges, biocompatibility and safety, government regulations, and several animal nonpredictive animal models in comparison to current therapies.

The existing challenges in breast cancer therapy and treatment has made researchers across the globe to come together and address the issues pertaining to existing therapy. Nanomedicine has emerged as an effective area in treatment of breast cancer therapy. However, toxicity issues of nanomaterial should be taken care of before going on further with clinical trials. In this regard, the countries and agencies have also formed some regulatory guidelines to be followed by scientist and researchers working in this field. The chapter focuses on some common nanomaterials employed for breast cancer therapy, their toxicity issues, possible reasons for causing toxicity, current innovative therapies for cancer treatment, and regulatory aspect of breast cancer nanomedicine.

In recent years, nanostructures have come to represent a new class of materials which have been explored for healthcare-related applications. These nanohybrids are important for their unique physicochemical properties as well as their ultra-small size, tunable optical emission, extremely high surface area to volume ratio, and enhanced mechanical properties. This chapter deliberates different strategies to fabricate nanohybrid structures for biomedical applications. We first describe the fabrication and bioconjugation of hybrid nanostructured materials. Then, we elaborate in detail about the different types of nanohybrid structures including nanoparticles (NPs), micelles, carbon-based NPs, fullerenes and carbon nanotubes, metal NPs, and polymeric NPs, etc. Finally, applications of nanostructure scaffolds in different biomedical fields are also discussed.

Correction for ‘Self-assembly of bovine serum albumin (BSA)–dextran bio-nanoconjugate: structural, antioxidant and in vitro wound healing studies’ by Sonali S. Rohiwal et al., RSC Adv., 2021, 11, 4308–4317, DOI: 10.1039/D0RA09301G.

This study for the first time shows the effective utilization and production of chitin monomers at laboratory level, with immense potential for its biomedical application. Low molecular weight (LMW) N-acetylglucosamine (GlcNAc) is prepared by depolymerization of chitin using chemical method coupled with a physical separation method. A novel filtration strategy exploiting polysulfone hollow fiber membrane is used for the preparation of GlcNAc particles with 94% yield within 8.5 ± 0.5 h. This high efficiency is analyzed using high-pressure liquid chromatography. The GlcNAc obtained was further analyzed using dynamic light scattering, first derivative Fourier transform infrared spectroscopy, and X-ray diffraction techniques. The antimicrobial properties of GlcNAc, chitin, and GlcNAc/chitin mixture were investigated using minimal inhibitory concentration against S. aureus and E. coli. Bacteriostatic property was exhibited by high molecular weight chitin, while GlcNAc and GlcNAc/chitin mixture (LMW) de...

Herein, we have developed organic dye (turmeric) sensitized functionalized multi-walled carbon nanotubes (MWCNTs)-titanium dioxide (TiO2) composite and investigated it's optically controlled resistive switching (RS) and non-volatile memory properties. The composite was synthesized using a single-step hydrothermal method and the dye sensitization period was varied to investigate the effect of the dye loading time (6, 12, 18, and 24 h) on the different properties of the composite. The structural, morphological, and optical properties of the bare and dye-sensitized composites were characterized using X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, and UV–visible spectrometer. The electrical properties of the bare and dye-sensitized composite based devices were tested in the dark, UV, visible, and UV + visible light illumination conditions. Due to the good absorbance properties of the TiO2 in UV region and dye in the visible region, the dye-sensitized composite devices show excellent bipolar RS and non-volatile memory properties in the UV + visible light illumination condition. In this work, the 18 h dye-sensitized device shows superior optical RS properties than other devices. The memristive properties of the optimized devices are reported and demonstrated that the UV + visible light illumination condition provides double valued charge-flux property and best in class charge driving capability. The electrical transport and possible optically controlled RS mechanisms are discussed. The results suggested that the optical stimulus can be an additional parameter in conjunction with the electric stimulus to control the RS properties of the devices.

Magnetite nanoparticles coated with bovine serum albumin (BSA@Fe3O4 MNPs) were used for efficient isolation and detection of genomic DNA from pathogen, Ochrobactrum anthropi. The pH tunable BSA-coated magnetic nanoparticles (BSA@Fe3O4) were synthesized by co-precipitation method and are shown to be capable of adsorbing almost 99 % of calf thymus DNA, from where it also can be efficiently desorbed by changing the pH of the suspension to 8. This finding enables efficient magnetic enrichment of DNA, followed by in-situ PCR of DNA. Over all, the detection limit of the method is 0.01 pg⋅mL‾1 for the genomic DNA of Ochrobactrum anthropi. The process does not require organic solvents or sophisticated equipment. Such an approach to fabricate and employ charge responsive Fe3O4@BSA magnetic nanoparticles for detection of pathogen has potential diagnostic and clinical applications.

A novel nanocomposite having DNA-assembled Fe3O4@Ag nanorods in silica matrix has been proposed for fabrication of bienzymatic cholesterol nanobiosensor. Cholesterol oxidase and horseradish peroxidase have been co-encapsulated in Silica/Fe3O4@Ag-DNA nanocomposite deposited on the indium tin oxide electrode. Cyclic voltammetry was employed for the electrochemical behavior of proposed biosensor and used to estimate cholesterol with a linear range of 5-195 mg/dL.

Protein nanoparticles have several distinct intrinsic advantages; however, their ex vivo colloidal stability in biological media was not fully explored. The stability of bovine serum albumin (BSA) nanoparticles (NPs) were found to be relatively higher in glucose, distilled water and NaCl as compared to Dulbecco's Modified Eagle Medium (DMEM) and phosphate buffer saline (PBS). A slight variation in the hydrodynamic diameter of BSA NPs was observed after 48 h of incubation period in different biological medium. However, for the particles suspended in DMEM a significant increase in hydrodynamic diameter was observed. Transmission electron microscopy and atomic force microscopy reveals the size and semi-spherical morphology of the BSA NPs which are obtained to be in the range of 50–150 nm. The BSA NPs were fully explored and the structural changes were investigated which confirms about the conformational stability of the NPs suspended in different biological media. The physical stability of the nanoparticles was investigated by zeta potential measurement and they were shown to be quite stable. The suitable biological media for higher colloidal and conformational stability has been anticipated which indicates the potential of BSA NPs to be used as an effective drug carrier.

The protein nanoparticles formulation is a challenging task as they are prone to undergo conformational transitions while processing which may affect bioavailability for bioactive compounds. Herein, a modified desolvation method is employed to prepare Bovine Serum Albumin nanoparticles, with controllable particle size ranging from 100 to 300 nm and low polydispersity index. The factors influencing the size and structure of BSA NPs viz. protein concentration, pH and the conditions for purification are well investigated. The structure of BSA NPs is altered due to processing, and may affect the effective binding ability with drugs and bioactive compounds. With that aims, investigations of molecular characteristics of BSA NPs are carried out in detail by using spectroscopic techniques. UV–visible absorption and Fourier Transform Infrared demonstrate the alteration in protein structure of BSA NPs whereas the FT-Raman spectroscopy investigates changes in the secondary and tertiary structures of the protein. The conformational changes of BSA NPs are observed by change in fluorescence intensity and emission maximum wavelength of tryptophan residue by fluorescence spectroscopy. The field emission scanning electron and atomic force microscopy micrographs confirm the size and semi-spherical morphology of the BSA NPs. The effect of concentration and pH on particle size distribution is studied by particle size analyzer.

Magnetic nanoparticles–DNA interactions can open up new possibilities in various biomedical applications. The interaction is based on the fundamental properties of DNA and magnetic nanoparticles. Hence, the properties of DNA as well as the magnetic nanoparticles reported so far have been extensively covered. The mechanisms involved in the DNA–MNP interaction are covered as evident from the literature. Different surface modifications used for DNA adsorption along with the possible modes of interaction are also covered along with their respective biomedical applications.

Magnetic adsorption technology of polymer functionalized superparamagnetic nanoparticles is showing great potential in biomedical applications because of their facile “on and off” state of magnetization. Highly magnetized superparamagnetic nanoparticle based magnetic adsorption technology was employed for the purification of DNA. The core–shell Fe3O4 nanoparticles were synthesized by alkaline precipitation and subsequently coated with silica by sol–gel method. Further, silica coated Fe3O4 nanoparticles functionalized with chitosan were used as an adsorbent for DNA. The surface adsorption of DNA onto the modified nanoparticles was optimized as a function of pH, time and temperature. The adsorption efficiency of Fe3O4@silica@chitosan nanoparticles was examined by UV visible spectroscopy. Fe3O4@silica@chitosan nanoparticles with the high adsorption efficiency of ∼88% and a high elution efficiency of ∼98% were employed for DNA isolation from human saliva. Agarose gel electrophoresis was used to validate the quality and quantity of DNA isolated from human saliva. Square wave voltammetry was carried out for monitoring the quantitative information about DNA fragment concentration. This method has potential application in the field of bioelectrochemical analysis. The isolation results of genomic DNA from saliva indicated that the Fe3O4@silica@chitosan nanoparticles have outstanding advantages in operation, selectivity, and capacity over the present existing isolation protocols (phenol–chloroform extraction). Furthermore, it opens up new opportunities in detection and isolation of nucleic acid.

A novel strategy to fabricate hydrogen peroxide third generation biosensor has been developed from sol–gel of silica/chitosan (SC) organic–inorganic hybrid material assimilated with iron oxide magnetic nanoparticles (Fe3O4). The large surface area of Fe3O4 and porous morphology of the SC composite facilitates a high loading of horseradish peroxidase (HRP). Moreover, the entrapped enzyme preserves its conformation and biofunctionality. The fabrication of hydrogen peroxide biosensor has been carried out by drop casting of the SC/F/HRP nanocomposite on glassy carbon electrode (GCE) for study of direct electrochemistry. The x-ray diffraction (XRD) pattern and transmission electron microscopy (TEM) confirms the phase purity and particle size of as-synthesized Fe3O4 nanoparticles, respectively. The nanocomposite was characterized by UV–vis spectroscopy, fluorescence spectroscopy and Fourier transform infrared (FTIR) for the characteristic structure and conformation of enzyme. The surface topographies of the nanocomposite thin films were investigated by scanning electron microscopy (SEM). Dynamic light scattering (DLS) was used to determine the particle size distribution. The electrostatic interactions of the SC composite with Fe3O4 nanoparticles were studied by the zeta potential measurement. Electrochemical impedance spectroscopy (EIS) of the SC/F/HRP/GCE electrode displays Fe3O4 nanoparticles as an excellent candidate for electron transfer. The SC/F/HRP/GCE exhibited a pair of well-defined quasi reversible cyclic voltammetry peaks due to the redox couple of HRP-heme Fe (III)/Fe (II) in pH 7.0 potassium phosphate buffer. The biosensor was employed to detect H2O2 with linear range of 5 μM to 40 μM and detection limit of 5 μM. The sensor displays excellent selectivity, sensitivity, good reproducibility and long term stability.