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Among all the nanoparticles synthesized; silver nanoparticles have attained special place in the area of nano technology because of their antimicrobial, nontoxic, environmentally safe and biomedical applications. In general; their syntheses involves the use of hazardous chemicals or costly physical methods. However, the biological processes are making their ways in between and proving their advantages over them. The use of plants and their extracts is one of the most valuable methods which are gaining concerns due to their imperative biological benefits. Plants are not only beautiful but majestic because they are rich sources of various medicinally important substances. They explore the huge diversity which can be utilized towards rapid and single step protocol preparatory method for various nanoparticles keeping intact “the green principles” over the conventional ones and proving their dominance for medicinal importance. Here, in the presented work “one pot synthesis of silver nanoparticles” is described. Therefore; a simple, cost effective bio-reduction on the principle of “green synthesis” of silver nanoparticles using the Alchemilla vulgaris plant extract is reported. The beauty of the synthesis is: no involvement of any surfactant, catalyst or template. The aqueous silver ions are reduced to silver nanoparticles when exposed to plant extract. The bio-reduction and stabilization of so formed silver nanoparticles was monitored by UV-Vis spectrophotometry, FTIR spectroscopy, SEM, particle size and zeta potential.

The current study was designed to evaluate the phytochemical profile and biological properties (antioxidant activity) of methanolic, ethyl-acetate and petroleum extracts of Alchemilla vulgaris which was traditionally used to alleviate and treat many diseases. Total phenolic content found in methanolic and ethyl acetate extract of Alchemillia vulgaris were 547.333 and 386.86 respectively. The phenolic content with respect to gallic acid was found to be 547.333 and 386.86 (μg gallic acid equivalent/ml of extract) for ethyl acetate and methanol extract. The flavonoid content was found to be as: 275.00 and 153.33 (μg rutin equivalents/ml of extract) in ethyl acetate and methanol extract. Free radicals are concerned in many disorders like neurodegenerative disease; cancer and AIDS. Antioxidants during their scavenging power are helpful for the management of those diseases. DPPH stable free radical method is an easy, rapid and receptive way tosurvey the antioxidant activity of a precise compound or plant extracts. IC5 0of the standard compounds, ascorbic acid was 8.59μg/ml. The uppermost radical scavenging activity was showed by ethyl acetate and methanolic extracts of Alchemillia vulgaris IC50= 66.71 and 23.47μg/ml respectively. The ethyl acetate extract has shown significantly low anti-radical activity compared to the methanolic extract. The results indicate that the extract reduces the radicals to the corresponding hydrazine when it reacts with the hydrogen donors in the antioxidant principle. The superior amount of phenolic compounds leads to further potent radical scavenging result as shown by Alchemillia vulgaris leaves extract.

Although several advances have been made in the field of medicine during the last few decades, yet targeted delivery of biomolecules is still a significant challenge. Thus, the present study illustrates the fabrication of dual nature magneto-conducting Fe3O4â��SU8 derived carbon-based Janus microbots that could deliver biomolecules efficiently inside cells. These microsystems possess dual properties, that is, the half part is magneto-conducting, and another half is only conducting for sufficing the therapeutic payloads efficiently under electromagnetic stimulations. These microbots are intrinsically fluorescent, which can help to trace them intracellularly without using any dye. UV photolithography was employed to design these low aspect ratio microbots (feature size â�¼2.5 I¼m diameter and 3.7 I¼m length) for attaining better control over locomotion with minimum magnetic field intensity. Interestingly, Janus microbots achieved a higher speed in the electric field (44 µm/s) as compared to the magnetic field (18 µm/s). Moreover, in vitro studies show a higher microbots uptake by HeLa cells in the presence of an external electric field as compared to without electrical field stimulation. © 2021 John Wiley & Sons Ltd.

Graphene oxide (GO) nanoparticles have been developed for a variety of biomedical applications as a number of different therapeutic modalities may be added onto them. Here, we report the development and testing of such a multifunctional GO nanoparticle platform that contains a grafted cell-targeting functionality, active pharmaceutical ingredients, and particulates that enable the use of magnetothermal therapy. Specifically, we demonstrate the ability to covalently attach hyaluronic acid (HA) onto GO, and the resultant nanoparticulates (GO-HA) exhibited low inherent toxicity toward two different breast cancer cell lines, BT-474 and MDA-MB-231. Doxorubicin (Dox) and paclitaxel (Ptx) were successfully loaded onto GO-HA with high and moderate efficiencies, respectively. A GO-HA-Dox/Ptx system was significantly better than the GO-Dox/Ptx system at specifically killing CD44-expressing MDA-MB-231 cells but not BT-474 cells that do not express CD44. Further, modified iron oxide nanoparticles were loaded onto the GO-HA-Dox system, enabling the use of magnetic hyperthermia. Hyperthermia in combination with Dox treatment through the GO-HA system showed significantly better performance in reducing viable tumor cell numbers when compared to the individual systems. In summary, we showcase a multifunctional GO nanoparticle system that demonstrates improved efficacy in killing tumor cells.

Metal-induced allergic contact dermatitis, particularly nickel, affects over 10 of the general population. Herein, chitosan-glycerol gel as protective barrier formulation was synthesized by neutralization reaction with an aim to reduce metal-ion diffusion into the skin to prevent allergy. Active functional groups in chitosan-glycerol gel were able to capture allergenic metal ions present in artificial sweat solution. The efficacy of the barrier formulation against nickel-ion penetration was evaluated ex vivo using pig skin. We found that the percutaneous absorption of nickel ion reduced by 98 when chitosan-glycerol gel was used as a barrier formulation. © Copyright © 2019 American Chemical Society.

Background The treatment of non-melanoma skin cancer and deadliest malignant melanoma skin cancer are the fifth and ninth most expensive treatments in Medicare, respectively. Moreover, the recurrence of cancer after currently available therapies, that is, surgery or radiotherapy, reduces the patient's life expectancy. Aims In view of this, we fabricated magnetic nanofibrous mat-based bandage to treat skin cancer non-invasively using an external alternating current (AC) magnetic field induced hyperthermia. Methods The Fe3 O4 nanoparticles incorporated polycaprolactone (PCL) fibers based bandages were fabricated using the electrospinning technique. The efficacy of the bandage was investigated in vitro using parental/doxorubicin hydrochloride (Dox)-resistant HeLa cells and in vivo using BALB/c mouse model in the presence of an external AC magnetic field (AMF). Results The PCL-Fe3 O4 fibrous mat-based bandages dissipate heat energy locally on the application of an external AMF and increase the surrounding temperature in a controlled way up to 45°C in a few mins. The in vitro study confirms the elevated temperature could kill parental and Dox-resistant HeLa cells significantly. As the activity of Dox enhanced at a higher temperatures, more than 85% of parental HeLa cells were dead when cells incubated with Dox contained fibrous mat in the presence of AMF for 10 minutes. Further, we confirm the full recovery of chemically induced skin tumors on BALB/c mice within a month after five hyperthermic doses for 15 minutes. Also, there was no sign of inflammation and recurrence of cancer post-therapy. Conclusion The present study confirms the PCL-Fe3 O4 nanofibrous based bandages are unique and compelling to treat skin cancer.

The poor penetration of anti-fungal agents into the cornea through the intact epithelium layer makes it difficult to treat acute fungal corneal infections. Herein, we developed Amphotret (amphotericin B) antifungal drug contained polycaprolactone-Fe3O4 (PCL-FO) magnetic nanofibers (MNFs) using the electrospinning technique. These MNFs generate heat in the presence of AC magnetic field (AMF) and release drug upon heating. MNFs were compatible with human mesenchymal stem cells (hMSCs) and HeLa cells, which exhibited unaltered proliferation, ruling out any toxicity from the systems. Hyperthermia induced via MNFs from 42 °C to 50 °C compromised the viability of Candida albicans cells. Further, the efficacy of the systems was increased in the presence of both heat and drug simultaneously in vitro, leading to near 100% loss in viability of C. albicans cells at 50 °C with simultaneous drug release from MNFs. Thus, we propose magnetic hyperthermia as adjunctive therapy for fungal keratitis.

The robust nature of a biocompatible fluorescent probe is demonstrated, by its detection of Fe3+ even after repeated rounds of quenching (reversibility) by acetate in real human blood samples and cells in vitro. Significantly trace levels of Fe3+ ions up to 8.2 nM could be detected, remaining unaffected by the existence of various other metal ions. The obtained results are validated by AAS and ICP-OES methods. A portable test strip is also fabricated for quick on field detection of Fe3+. As iron is a ubiquitous metal in cells and plays a prominent role in biological processes, the use of this probe to image Fe3+ in cells is a substantial development towards biosensing. Cytotoxicity studies also proved the nontoxic nature of this probe.

The robust nature of a biocompatible fluorescent probe is demonstrated, by its detection of Fe

The study presented in this work consists of two parts: The first part is the synthesis of Graphene oxide-Fe3O4 nanocomposites by a mechanochemical method which, is a mechanical process that is likely to yield extremely heterogeneous particles. The second part includes a study on the efficacy of these Graphene oxide-Fe3O4 nanocomposites to kill cancerous cells. Iron powder, ball milled along with graphene oxide in a toluene medium, underwent a controlled oxidation process. Different phases of GO-Fe3O4 nanocomposites were obtained based on the composition used for milling. As synthesized nanocomposites were characterized by x-ray diffraction (XRD), alternating magnetic field (AFM), Raman spectroscopy, and a vibrating sample magnetometer (VSM). Additionally, the magnetic properties required to obtain high SAR values (Specific Absorption Rate-Power absorbed per unit mass of the magnetic nanocomposite in the presence of an applied magnetic field) for the composite were optimized by varying the milling time. Nanocomposites milled for different extents of time have shown differential behavior for magneto thermic heating. The magnetic composites synthesized by the ball milled method were able to retain the functional groups of graphene oxide. The efficacy of the magnetic nanocomposites for killing of cancerous cells is studied in vitro using HeLa cells in the presence of an AC (Alternating Current) magnetic field. The morphology of the HeLa cells subjected to 10 min of AC magnetic field changed considerably, indicating the death of the cells.

Thermal therapy combined with chemotherapy is one of the advanced and efficient methods to eradicate cancer. In this work, we fabricated magnetically actuated smart textured (MAST) fibrous systems and studied their candidacy for cancer treatment. The polycaprolactone-Fe3 O4 based MAST fibers were fabricated using electrospinning technique. These MAST fibrous systems contained carbogenic quantum dots as a tracking agent and doxorubicin hydrochloride anticancer drug. Additionally, as fabricated MAST fibrous systems were able to deliver anticancer drug and heat energy simultaneously to kill HeLa cells in a 10 min period in vitro. After treatment, the metabolic activity and morphology of HeLa cells were analyzed. In addition, the mechanism of cell death was studied using flow cytometry. Interestingly, the navigation of these systems in the fluid can be controlled with the application of gradient magnetic field. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 40-51, 2018.

Surface energy plays a major role in prokaryotic and eukaryotic cell interactions with biomedical devices. In the present study, poly(e-caprolactone)-xFe3 O4 nanoparticles (PCL-xFO NPs; x = 0, 10, 20, 30, 40, 60 wt% FO concentration in PCL) composite thin films were developed for skin tissue regeneration. The surface properties in terms of roughness, surface energy, wettability of the thin films were altered with the incorporation of Fe3 O4 NPs. These thin films show antimicrobial properties and cyto-compatibility with NIH 3T3 mouse embryonic fibroblast cells. The porosity and thickness of the films were controlled by varying RPM of the spin coater. Interestingly, at 1000 RPM the roughness of the film decreased with increasing concentrations of FO NPs in PCL, whereas the surface energy increased with increasing FO NPs concentrations. Furthermore, the spreading of NIH-3T3 cells grown on PCL-xFO thin films was less as compared to control (TCPS), however cells overcame this effect after 48 h of seeding and cells spread similarly to those grown on TCPS after 48 h. Also, the incorporation of FO NPs in thin films induced inner membrane permeabilization in E. coli bacteria leading to bacterial cell death. The viability of E. coli bacteria decreased with increasing concentration of FO NPs in PCL. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 795-804, 2017.

Magnetic nanomotors with integrated theranostic capabilities can revolutionize biomedicine of the future. Typically, these nanomotors contain ferromagnetic materials, such that small magnetic fields can be used to maneuver and localize them in fluidic or gel-like environments. Motors with large permanent magnetic moments tend to agglomerate, which limits the scalability of this otherwise promising technology. Here, we demonstrate the application of a microwave-synthesized ferrite layer to reduce the agglomeration of helical ferromagnetic nanomotors by an order of magnitude, which allows them to be stored in a colloidal suspension for longer than six months and subsequently be manoeuvred with undiminished performance. The ferrite layer also rendered the nanomotors suitable as magnetic hyperthermia agents, as demonstrated by their cytotoxic effects on cancer cells. The two functionalities were inter-related since higher hyperthermia efficiency required a denser suspension, both of which were achieved in a single microwave-synthesized ferrite coating.

The objective of the present work is to understand the vertical electric field stimulation of the bacterial cells, when grown on amorphous carbon substrates in vitro. In particular, the antibacterial activity against Gram-positive Staphylococcus aureus and Gram-negative Escherichia coli are studied using MTTassay, live/dead assay and inner membrane permeabilization assays. In our experiments, the carbon substrate acts as one electrode and the counter electrode is positioned outside the culture medium, thus suppressing the current, electrokinetic motions and chemical reactions. Guided by similar experiments conducted in our group on neuroblastoma cells, the present experimental results further establish the interdependence of field strength and exposure duration towards bacterial growth inactivation in vitro. Importantly, significant reduction in bacterial viability was recorded at the 2.5 V/cm electric field stimulation conditions, which does not reduce the neural cell viability to any significant extent on an identical substrate. Following electrical stimulation, the bacterial growth is significantly inhibited for S. aureus bacterial strain in an exposure time dependent manner. In summary, our experiments establish the effectiveness of the vertical electric field towards bacterial growth inactivation on amorphous carbon substrates, which is a cell type dependent phenomenon (Gram-positive vs. Gram-negative). (C) 2014 Elsevier Ltd. All rights reserved.

Surface energy plays a major role in prokaryotic and eukaryotic cell interactions with biomedical devices. In the present study, poly(ε-caprolactone)-xFe

We demonstrate the efficacy of amorphous macroporous carbon substrates as electrodes to support neuronal cell proliferation and differentiation in electric field mediated culture conditions. The electric field was applied perpendicular to carbon substrate electrode, while growing mouse neuroblastoma (N2a) cells in vitro. The placement of the second electrode outside of the cell culture medium allows the investigation of cell response to electric field without the concurrent complexities of submerged electrodes such as potentially toxic electrode reactions, electro-kinetic flows and charge transfer (electrical current) in the cell medium. The macroporous carbon electrodes are uniquely characterized by a higher specific charge storage capacity (0.2 mC/cm2) and low impedance (3.3 kΩ at 1 kHz). The optimal window of electric field stimulation for better cell viability and neurite outgrowth is established. When a uniform or a gradient electric field was applied perpendicular to the amorphous carbon substrate, it was found that the N2a cell viability and neurite length were higher at low electric field strengths (≤2.5 V/cm) compared to that measured without an applied field (0 V/cm). While the cell viability was assessed by two complementary biochemical assays (MTT and LDH), the differentiation was studied by indirect immunostaining. Overall, the results of the present study unambiguously establish the uniform/gradient vertical electric field based culture protocol to either enhance or to restrict neurite outgrowth respectively at lower or higher field strengths, when neuroblastoma cells are cultured on porous glassy carbon electrodes having a desired combination of electrochemical properties.

Despite considerable research to develop carbon based materials for biomedical applications, the toxicity of carbon remains a major concern. In order to address this issue as well as to investigate the cell fate processes of neural cells from the perspective of neural tissue engineering applications, the in vitro cytocompatibility of polyacrylonitrile (PAN) derived continuous carbon nanofibers and PAN derived carbon thin films were investigated both quantitatively and qualitatively using in vitro biochemical assays followed by extensive flow cytometry analysis. The experimental results of Schwann cell fate, i.e. cell proliferation, cell metabolic activity and cell apoptosis on amorphous carbon substrates are discussed in reference to the time dependent evolution of intracellular oxidative stress. Apart from providing evidence that an electrospun carbon nanofibrous substrate can physically guide the cultured Schwann cells, this study suggested that continuous carbon nanofibers and amorphous carbon films are not cytotoxic in vitro and do not significantly induce apoptosis of Schwann cells, but in fact even facilitate their proliferation and growth.

The development of scaffolds for neural tissue engineering application requires an understanding of cell adhesion, proliferation, and migration of neuronal cells. Considering the potential application of carbon as scaffold materials and the lack of understanding of compatibility of amorphous carbon with neuronal cells, the carbon-based materials in the forms of carbon films and continuous electrospun carbon nanofibers having average diameter of ~200 nm are being investigated with or without ultraviolet (UV) and oxy-plasma (OP) treatments for cytocompatibility property using mouse Neuroblastoma (N2a) and rat Schwann cells (RT4-D6P2T). The use of Raman spectroscopy in combination with Fourier transform infrared (FTIR) and X-ray diffraction establishes the amorphous nature and surface-bonding characteristics of the studied carbon materials. Although both UV and OP treatments make carbon surfaces more hydrophilic, the cell viability of N2a cells is statistically more significant on OP treated fibers/films compared to UV fiber/film substrates after 4 days in culture. The electrospun carbon fibrous substrate provides the physical guidance to the cultured Schwann cells. Overall, the experimental results of this study demonstrate that the electrospun amorphous carbon nanofibrous scaffolds can be used as a suitable biomaterial substrate for supporting cell adhesion and proliferation of neuronal cells in the context of their applications as artificial nerve implants.