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The evolving dynamics of drug resistance due to tumor heterogeneity often creates impediments to traditional therapies making it a challenging issue for cancer cure. Breast cancer often faces challenges of current therapeutic interventions owing to its multiple complexities and high drug resistivity， for example against drugs like trastuzumab and tamoxifen. Drug resistance in the majority of breast cancer is often aided by the overtly expressed P-glycoprotein (P-gp) that guides in the rapid drug efflux of chemotherapy drugs. Despite continuous endeavors and ground-breaking achievements in the pursuit of finding better cancer therapeutic avenues, drug resistance is still a menace to hold back. Among newer therapeutic approaches, the application of phytonutrients such as alkaloids to suppress P-gp activity in drug-resistant cancers has found an exciting niche in the arena of alternative cancer therapies. In this work, we would like to present a black pepper alkaloid derivative known as BioPerine-loaded chitosan (CS)-polyethylene glycol (PEG) coated polylactic acid (PLA) hybrid polymeric nanoparticle to improve the bioavailability of BioPerine and its therapeutic efficacy in suppressing P-gp expression in MDA-MB 453 breast cancer cell line. Our findings revealed that the CS-PEG-BioPerine-PLA nanoparticles demonstrated a smooth spherical morphology with an average size of 316 nm, with improved aqueous solubility, and provided sustained BioPerine release. The nanoparticles also enhanced in vitro cytotoxicity and downregulation of P-gp expression in MDA-MB 453 cells compared to the commercial inhibitor verapamil hydrochloride, thus promising a piece of exciting evidence for the development of BioPerine based nano-drug delivery system in combination with traditional therapies as a crucial approach to tackling multi-drug resistance in cancers., Graphical abstract Image, graphical abstract

Cholesterol-rich arterial plaques characterize atherosclerosis, a significant cause of heart disease. Nutraceuticals have received attention over the years, demonstrating potential benefits towards treating and preventing cardiovascular diseases (CVD), including atherosclerosis. Curcumin, a potent polyphenol present in Curcuma longa, has shown remarkable anti-atherosclerotic activity via anti-inflammatory and anti-oxidative properties. The bioavailability and low water solubility of curcumin limit its clinical translational purposes. These issues can be circumvented effectively by nano-drug delivery systems that can target atherosclerotic plaque sites. In this work, we chose to use curcumin and a natural bioenhancer called Bioperine (derived from Piper nigrum) inside a polymeric nano-drug delivery system for targeting atherosclerotic plaque sites. We selected two different ratios of curcumin:Bioperine to study its comparative effect on the inhibition of oxidized low-density lipoprotein (Ox-LDL)-induced foam cell formation. Our studies demonstrated that Cur-Bio PLGA NPs (both ratios) maintained the cell viability in THP-1 monocyte-derived macrophages above 80% at all periods. The 1:0.2:10 ratio of Cur-Bio PLGA NPs at a concentration of 250 μg/mL illustrated an enhanced reduction in the relative cholesterol content in the THP-1-derived foam cells compared to the 1:1:10 ratio. Confocal microscopy analysis also revealed a reduction in macrophage-mediated foam cell formation when administered with both the ratios of Cur-Bio PLGA NPs. Relative fold change in the mRNA expression of the genes involved in the inflammatory pathways in the atherosclerotic process downregulated NF-κB, CCL2/MCP-1, CD-36, and STAT-3 activity while upregulating the SCAR-B1 expression when treated with the Cur-Bio PLGA NPs. This study thus highlights the importance of natural-based compounds towards the therapeutic intervention against atherosclerotic activity when administered as preventive medicine.

Magnetic analogue of an isolated free electric charge, i.e., a magnet with a single north or south pole, is a long sought-after particle which remains elusive so far. In magnetically frustrated pyrochlore solids, a classical analogue of monopole was observed as a result of excitation of spin ice vertices. Direct visualization of such excitations were proposed and later confirmed in analogous artificial spin ice (ASI) systems of square as well as Kagome geometries. However, such magnetically charged vertices are randomly created as they are thermally driven and are always associated with corresponding equal and opposite emergent charges, often termed as monopole–antimonopole pairs, connected by observable strings. Here, we demonstrate a controlled stabilisation of a robust isolated emergent monopole-like magnetically charged vertices in individual square ASI systems by application of an external magnetic field. The excitation conserves the magnetic charge without the involvement of a corresponding excitation of opposite charge. Well supported by Monte Carlo simulations our experimental results enable, in absence of a true elemental magnetic monopole, creation of electron vortices and studying electrodynamics in presence of a monopole-like field in a solid state environment.

Atherosclerosis is Caesar’s sword, which poses a huge risk to the present generation. Understanding the atherosclerotic disease cycle would allow ensuring improved diagnosis, better care, and treatment. Unfortunately, a highly effective and safe way of treating atherosclerosis in the medical community remains a continuous challenge. Conventional treatments have shown considerable success, but have some adverse effects on the human body. Natural derived medications or nutraceuticals have gained immense popularity in the treatment of atherosclerosis due to their decreased side effects and toxicity-related issues. In hindsight, the contribution of nutraceuticals in imparting enhanced clinical efficacy against atherosclerosis warrants more experimental evidence. On the other hand, nanotechnology and drug delivery systems (DDS) have revolutionized the way therapeutics are performed and researchers have been constantly exploring the positive effects that DDS brings to the field of therapeutic techniques. It could be as exciting as ever to apply nano-mediated delivery of nutraceuticals as an additional strategy to target the atherosclerotic sites boasting high therapeutic efficiency of the nutraceuticals and fewer side effects.

Materials with efficient potential in imaging as well as therapy are gaining particular attention in current medical research. Photodynamic therapy (PDT) has been recently recognized as a promising treatment option for solid tumors. Still, most of the nanomaterial-based PDT modules either employ an additional photosensitizer or require high power laser sources. Also, they suffer from a lack of responsiveness in the near-infrared (NIR) region. Nanomaterials that could realize PDT independently (without any photosensitizer), at safe laser dose and in the deep tissue penetrative NIR region would definitely be better solid tumor treatment options. Methods: Herein, Cu- and Bi-based bimetal chalcogenide (Cu3BiS3), with absorption in the NIR region was developed. High-performance PDT of cancer and high-contrast x-ray imaging of tumor were performed in vivo. Biocompatibility of the NCs was also assessed in vivo. Results: The highlight of the results was the realization of ultra-low dose NIR laser-mediated PDT, which has not been achieved before, leading to complete tumor regression. This could be a breakthrough in providing a pain- and scar-less treatment option, especially for solid tumors and malignant/benign subcutaneous masses. Though the NCs are active in the photo-thermal therapy (PTT) regime as well, focus is given to the exciting aspect of extremely low power-induced PDT observed here. Conclusion: Their extended in vivo biodistribution with commendable hemo- and histo-compatibilities, along with imaging and multi-therapeutic capabilities, project these Cu3BiS3 NCs as promising, prospective theranostic candidates.

Bioinert gold nanoparticles of various shapes and functionalities are widely accepted as contrast agents (CAs) for several modalities of imaging, viz., electron microscopy, computerized tomography (CT), X-ray and photoacoustic (PA) imaging. However, testing of novel compact-imaging probes for ocular diagnostic imaging is always challenging. Here, ultra-fast microwave oven synthesized gold nanocages (AuNcgs) were successfully demonstrated for high-contrast PA ocular imaging for the first time. Methods are described for the synthesis, characterization and application of quickly synthesized AuNcgs in diagnostic ocular imaging. PA and ultrasound (US) images were acquired using a commercial US imaging scanner integrated with a tunable nanosecond pulsed laser. This integrated hybrid-modality system is a combined PA and US platform for imaging which enabled acquiring of complementary structural and optical absorption-based information simultaneously. Initial experiments were conducted using tubings filled with solutions of different concentrations of quickly synthesized AuNcgs. Biological PA and US imagings were demonstrated using enucleated porcine eye samples. Based on the acquired results, it is envisaged that AuNcgs can be employed as a high strength PA CA to potentially diagnose ocular disease like uveal melanoma in the near future. MOE (Min. of Education, S’pore) Accepted version

Design of safe and efficient vehicles for the combinatorial delivery of drugs and genetic agents is an emerging requisite for achieving enhanced therapeutic effect in cancer. Even though several nanoplatforms have been explored for the co-delivery of drugs and genetic materials the translation of these systems to clinical phase is still a challenge, mainly due to tedious synthesis procedures, lack of serum stability, inefficient scalability etc. Here in, we report development of reduction and pH sensitive polymeric graft of low molecular weight poly (styrene -alt -maleic anhydride) and evaluation of its efficacy in co-delivering drug and siRNA. The polymer was modified with suitable components, which could help in overcoming various systemic and cellular barriers for successful co-delivery of drugs and nucleic acids to cancer cells, using simple chemical reactions. The polymeric derivative could easily self assemble in water to form smooth, spherical micellar structures, indicating their scalability. Doxorubicin and PLK-1 siRNA were selected as model drug and nucleic acid, respectively. Doxorubicin could be loaded in the self assembling micelles with an optimum loading content of ∼8.6% w/w and efficient siRNA complexation was achieved with polymer/siRNA weight ratios >40. The polyplexes were stabilized in physiological saline by coating with bovine serum albumin (BSA). Stable drug loaded nanoplexes, for clinical administration, could be easily formulated by gently dispersing them in physiological saline containing appropriate amount of albumin. Drug release from the nanoplexes was significantly enhanced at low pH (5) and in the presence of 10 mM glutathione (GSH) showing their dual stimuli sensitive nature. In vitro cell proliferation assay and in vivo tumor regression study have shown synergistic effect of the drug loaded nanoplexes in inhibiting cancer cell proliferation. Facile synthesis steps, scalability and ease of formulation depict excellent clinical translation potential of the proposed nanosystem.

Gold nanocages (AuNcgs) are well-studied, hollow, metallic nanostructures that have fascinated researchers in the fields of nanotechnology, materials science, photoelectronics, biotechnology, and medical science for the last decade. However, the time-consuming synthesis of AuNcgs has limited their widespread use in materials science and nano-biotechnology. A novel, ultra-fast, simple, and highly convenient method for the production of AuNcgs using microwave heating is demonstrated herein. This quick method of AuNcg synthesis requires mild laboratory conditions for large-scale production of AuNcgs. The microwave heating technique offers the advantage of precise mechanical control over the temperature and heating power, even for the shortest reaction period (i.e., seconds). Microwave-synthesized AuNcgs were compared with conventionally synthesized AuNcgs. Structural maneuver studies employing the conventionally produced AuNcgs revealed the formation of screw dislocations and a shift in the lattice plane. Detailed characterization of the microwave-generated AuNcgs was performed using high resolution transmission electron microscopy (HRTEM), scanning electron microscopy (SEM), X-ray powder diffraction (XRD), and spectroscopic techniques.

Despite aggressive surgical resections and combinatorial chemoradiations, certain highly malignant populations of tumor cells resurrect and metastasize. Mixed-grade cancer cells fail to respond to standard-of-care therapies by developing intrinsic chemoresistance and subsequently result in tumor relapse. Macroautophagy is a membrane trafficking process that underlies drug resistance and tumorigenesis in most breast cancers. Manipulating cellular homeostasis by a combinatorial nanotherapeutic model, one can evaluate the crosstalk between type I and type II cell death and decipher the fate of cancer therapy. Here, we present a multi-strategic approach in cancer targeting to mitigate the autophagic flux with subcellular toxicity via lysosome permeation, accompanied by mitochondrial perturbation and apoptosis. In this way, a nanoformulation is developed with a unique blend of a lysosomotropic agent, an immunomodulating sulfated-polysaccharide, an adjuvant chemotherapeutic agent, and a monoclonal antibody as a broad-spectrum complex for combinatorial nanotherapy of all breast cancers. To the best of our knowledge, this manuscript illustrates for the first time the applications of advanced microscopic techniques such as electron tomography, three-dimensional rendering and segmentation of subcellular interactions, and fate of the multifunctional therapeutic gold nanocages specifically targeted toward breast cancer cells.

Morusin, a water-insoluble prenylated flavonoid is known for its numerous medicinal properties. It manifests its anticancer potential by suppression of genes involved in tumor progression. However, poor solubility of the drug results in low bioavailability and rapid degradation thus hindering its clinical utilization. In order to overcome this, we have synthesized a niosome system composed of non-ionic surfactant span 60 and cholesterol using a thin-layer evaporation technique to improve the aqueous-phase solubility of the drug. Highly cytocompatible niosomes of 479 nm average size with smooth and uniform spherical morphology were synthesized in a facile manner. Unlike free morusin, nanomorusin was found to be freely dispersible in aqueous media. Having an extremely high drug entrapment efficiency (97%), controlled and sustained release of morusin resulting in enhanced therapeutic efficacy was observed in cancer cell lines of 4 different lineages. The results demonstrate that the morusin-niosome system is a promising strategy for enhanced anti-cancer activity against multiple cancer types and could be an indispensable tool for future targeted chemotherapeutic strategies.

Details of a fast and sustainable bottom-up process to grow large area high quality graphene films without the aid of any catalyst are reported in this paper. We used Melaleuca alternifolia, a volatile natural extract from tea tree plant as the precursor. The as-fabricated graphene films yielded a stable contact angle of 135°, indicating their potential application in very high hydrophobic coatings. The electronic devices formed by sandwiching pentacene between graphene and aluminum films demonstrated memristive behavior, and hence, these graphene films could find use in nonvolatile memory devices also.

A size and shape tuned, multifunctional metal chalcogenide, Cu2S-based nanotheranostic agent is developed for trimodal imaging and multimodal therapeutics against brain cancer cells. This theranostic agent was highly efficient in optical, photoacoustic and x-ray contrast imaging systems. The folate targeted, NIR-responsive photothermal ablation in synergism with the chemotherapeutic action of doxorubicin proved to be a rapid precision guided cancer-killing module. The multi-stimuli, i.e., pH-, thermo- and photo-responsive drug release behavior of the nanoconjugates opens up a wider corridor for on-demand, triggered drug administration. The simple synthesis protocol, combined with the multitudes of interesting features packed into a single nanoformulation, clearly demonstrates the competing role of this Cu2S nanosystem in future cancer treatment strategies.

Nanoarchitectures of titania (TiO2) have been widely investigated for a number of medical applications including implants and drug delivery. Although titania is extensively used in the food, drug and cosmetic industries, biocompatibility of nanoscale titania is still under careful scrutiny due to the conflicting reports on its interaction with cellular matter. For an accurate insight, we performed in vitro studies on the response of human dermal fibroblast cells toward pristine titania nanotubes fabricated by anodic oxidation. The nanotubes at low concentrations were seen to induce toxicity to the cells, whereas at higher concentrations the cell vitality remained on par with controls. Further investigations revealed an increase in the G0 phase cell population depicting that majority of cells were in the resting rather than active phase. Though the mitochondrial set-up did not exhibit any signs of stress, significantly enhanced reactive oxygen species production in the nuclear compartment was noted. The TiO2 nanotubes were believed to have gained access to the nuclear machinery and caused increased stress leading to genotoxicity. This interesting property of the nanotubes could be utilized to kill cancer cells, especially if the nanotubes are functionalized for a specific target, thus eliminating the need for any chemotherapeutic agents.

Carbon nitride (CNx) nanofibers is successfully utilised as cathode catalyst in microfluidic fuel cell (MFC) using electrospinning technique. The electrochemical measurement for CNx nanofibers as cathode catalyst in MFC is studied and compared with that of Pt and Au cathodes. Formic acid is employed as fuel, KMnO4 as oxidant and H2SO4 as supporting electrolyte. CNx nanofibers is shown to be not active towards formic acid oxidation and as a result, is tolerant to fuel crossover effect as compared to Pt and Au cathode. CNx nanofibers enable MFC to operate at a wider range of flow rates of fuel and oxidant as compared to Pt and Au conventionally used. MFC utilising CNx nanofibers gives higher power density of 3.43 mW cm−2 and the current density of 9.79 mAcm−2, as compared to that utilizes pure Au (2.72 mW cm−2, 6.04 mA cm−2) and Pt (3.09 mW cm−2, 6.18 mA cm−2) as anode.

Hypermethylated cancer populations are hard to treat due to their enhanced chemo-resistance, characterized by aberrant methylated DNA subunits. Herein, we report on invoking response from such a cancer lineage to chemotherapy utilizing multifunctional copper telluride (Cu2−XTe) nanocubes (NCs) as photothermal and photodynamic agents, leading to significant anticancer activity. The NCs additionally possessed photoacoustic and X-ray contrast imaging abilities that could serve in image-guided therapeutic studies.

Silica nanoparticles have been prepared from tetraethylorthosilicate dissolved in ethanol followed by base-catalyzed condensation. Earlier works reported that at least four parameters, namely concentration of tetraethylorthosilicate, ethanol, water and ammonia solution are needed to be optimized for the size tuning of silica nanoparticles. In this work size tuning of 5 nm–250 nm has been achieved by varying a single synthesis parameter i.e., the concentration of ammonia solution. Oxygen plasma was found to be successful for generating pores on silica nanoparticles without using any structure directing agents. The properties and morphology of nanoparticles were investigated by transmission electron microscopy, scanning electron microscopy, energy dispersive X- ray spectroscopy and Fourier transformed infrared spectroscopy.

Electrospinning has been recognized as an efficient technique for the forming of polymer nanofibers. Silk fibroin (SF) nanofibers were electrospun from SF solution using trifluoroacetic acid solution as a solvent. In the present work, we have systematically evaluated the effects of instrument parameters, including applied voltage, tip-target distance, solution flow rate, solution parameters; such as polymer concentration and solution viscosity on the morphology of electrospun SF fibers. The applied voltage and flow rate was monitored at fixed tip target distance during the electrospinning process and it was correlated with the characteristics of the fibers obtained. The number of deposited fibers also increases with the applied voltage. Also, viscosity, flow rate and applied voltage strongly affect the shape and morphology of the fibers. A particular interest, we demonstrated that by monitoring the applied voltage and flow rate it is possible to control the fibers morphology and bead concentration. Rheological study showed a strong dependence of spinnability and fiber morphology on solution viscosity. Solution concentrations has been found to most strongly affect fiber size, with fiber diameter increasing with increasing solution concentration and the morphology of the deposition on the collector changed from spherical beads to interconnected fibrous networks. FTIR analysis clearly shows that there are no spectral differences between fibers and which suggests that there was no chemical modification developed during the process. Under optimized conditions, homogenous (not interconnected) SF fibers with a mean diameter of 234 nm were prepared.

Zinc aluminate nanoparticles with average particle size of 40 nm were synthesized using a sol–gel combustion method. X-ray diffractometry result was analysed by Rietveld refinement method to establish the phase purity of the material. Different stages of phase formation of the material during the synthesis were investigated using differential scanning calorimetry and differential thermogravimetric analysis. Particle size was determined with transmission electron microscopy and the optical bandgap of the nanoparticles was determined by absorption spectroscopy in the ultraviolet-visible range. Dielectric permittivity and a.c. conductivity of the material were measured for frequencies from 100 kHz to 8 MHz in the temperature range of 30–120°C. The presence of Maxwell–Wagner type interfacial polarization was found to exist in the material and hopping of electron by means of quantum mechanical tunneling is attributed as the reason for the observed a.c. conductivity.

Nanoparticles of cobalt ferrite were synthesized by sol gel method. These particles were structurally characterized by using X-Ray Diffraction and Transmission Electron Microscopy, High Resolution Transmission Electron Microscopy, Energy Dispersive Spectrum and Inductively Coupled Plasma Analysis and the results confirmed the formation of spherically shaped nanoparticles of cobalt ferrite having a size lying in the range of 13–14 nm. The as prepared sample was sintered at 800 °C and the structural, magnetic and dielectric properties were measured. The dielectric properties were studied and analyzed as a function of temperature and frequency. The ac and dc conductivity studies were carried out to delve into the conduction mechanism. The existing models based on quantum mechanical tunneling were effectively employed to explain the frequency dependent conductivity.

Nano magnetic oxides are promising candidates for high density magnetic storage and other applications. Nonspherical mesoscopic iron oxide particles are also candidate materials for studying the shape, size and strain induced modifications of various physical properties viz. optical, magnetic and structural. Spherical and nonspherical iron oxides having an aspect ratio, ∼2, are synthesized by employing starch and ethylene glycol and starch and water, respectively by a novel technique. Their optical, structural, thermal and magnetic properties are evaluated. A red shift of 0·24 eV is observed in the case of nonspherical particles when compared to spherical ones. The red shift is attributed to strain induced changes in internal pressure inside the elongated iron oxide particles. Pressure induced effects are due to the increased overlap of wave functions. Magnetic measurements reveal that particles are superparamagnetic. The marked increase in coercivity in the case of elongated particles is a clear evidence for shape induced anisotropy. The decreased specific saturation magnetization of the samples is explained on the basis of weight percentage of starch, a nonmagnetic component and is verified by TGA and FTIR studies. This technique can be modified for tailoring the aspect ratio and these particles are promising candidates for drug delivery and contrast enhancement agents in magnetic resonance imaging.

We prepared plasma-polymerized thin films from a mixed gas of carbon dioxide and 1,3-butadiene. Their XPS and FT-IR spectra revealed that hydrophilic groups such as hydroxyl, carboxyl and carbonyl groups existed in the thin films. The content of the C-H carbons gradually decreased with increase in the plasma output power or the CO2/butadiene flow rate ratio, while the amounts of carbonyl and carboxyl carbons increased correspondingly. In addition, coating of the plasma-polymerized CO2/butadiene thin film on a polytetrafluoroethylene substrate was found to enhance the adhesion strength when the surface-modified substrate was bonded to a steel plate with an α-cyanoacrylate adhesive. These superior adhesion properties of the plasma-polymerized thin films formed on the substrates indicate that the oxygen-containing functional groups formed at the film surface play a major role in increasing the adhesion strength.

We have developed a polymer film by plasma polymerizing MnTPPCl and characterized it by various optical and electrical methods and studied its application as a chemical sensor to detect H2O2 and as a bio-sensor to detect glucose. For characterization of the plasma polymer we have used UV-Vis spectroscopy, IR, SEM, AFM, ESCA and cyclic voltammetry. Plasma polymerized MnTPPCl was found to be a promising candidate in the field of bio and chemical sensors.

RNA interference and the therapeutic applications using small interfering RNA was discovered more than 10 years ago and currently is used in various applications including in therapeutic field. However the research in this field is still in its infancy. Many challenges like safe delivery of targeted siRNA to nucleus and cytosol of cancerous cells without compromising the activity of siRNA needs to be addressed. We have overcome this hurdle with the help of nanotechnology using PLGA hollow nanoparticles (PLGAHNPs) and suppressing the oncogene of MYC transcription factors by using anti myc-siRNAs in human cancer cell lines. siRNA was encapsulated in PLGAHNPs. These spherical PLGAHNPs of size 70 nm had high efficiency of gene release at pH 4.2 under in vitro conditions. Cell penetrating peptide (CPP)- Tat peptide (TAT) and peptide nucleic acidnucleolus localizing signal (PNA-NLS) was used for siRNA delivery without affecting the therapeutic activity of siRNA. The siRNA duplex was prepared using T7 polymerase and double stranded DNA through in vitro transcription. Incubation of the siRNA encapsulated PLGAHNPs functionalized with TAT and PNA-NLS (TAT-siRNA-PNA-PLGAHNPs-siRNA) with cancer cells resulted in reduced cell proliferation. A downregulation of gene expression by 90% was observed even with low concentration of siRNA. We found complete arrest of cell division which was mediated by downregulation of MYC expression.

Plasma treatments of polyethylene surfaces with halogens, especially bromine and iodine were investigated. In addition, after halogen plasma treatment had been done, the treated substrate was exposed to the vapor of same halogen to increase the contents of the halogen in the substrates. From the results by ESCA analysis, it became apparent that the bromine and the iodine had been bonded chemically into the surface of polyethylene substrate. The reaction of I2-plasma-treated polyethylene with amino alcohol solution made the substrate hydrophilic.

Curcin, a type 1 ribosome inactivating protein (RIP) is investigated here for its cellular competence on six mammalian cell lines. Cells exposed to curcin (100 μg/ml) for 72 h exhibited significant cellular metabolic arrest, with the cancer cell lines being more sensitive. The viability assessment of the cancer cells in a 3D cell culture based assay revealed highly restricted sprouting and proliferation with near to complete dead cell population. Prominent mitochondrial dysfunction, elevated reactive oxygen species levels, nuclear degeneration, structural/mechanical destabilization and suppression of defense mechanisms were imminent with the RIP treated cells. Expression levels of nuclear factor κB (NF-κB), cytoskeletal focal adhesion kinases (FAK) and vinculin were significantly diminished. Vital cellular organelles as nucleus, mitochondria and actin were severely incapacitated on RIP exposure resulting in multimodal apoptosis and necrosis. The ability of curcin to impart comprehensive shutdown of the cells, especially cancer cells, complemented with its hemocompatibility, opens up possibilities of utilizing this ribotoxin as a prospective therapeutic candidate against cancers of diverse origins.

Dark conduction in radio frequency plasma polymerized Furan thin film is reported. A contact limited Schottky mechanism is found to predominate. A comparison of the value from different experimental studies and the value from theoretical studies confirm the Schottky type mechanism in Furan thin film.

The ring-opening polymerization of L,L-lactide by using immobilized lipase Candida Antarctica (Novozym 435) as a catalyst at a temperature of 100 °C in bulk was conducted. This process was found to yield the corresponding poly(L,L-lactide) (PLLA) with weight-average of molecular weights of about 2,440 and a polydispersity index of 2.63. It was observed that the increase of the reaction time and amount of enzyme catalyst resulted in the polylactides with higher molecular weights.

Fluorinated graphene oxide (FGO) is reported for the first time as a magnetically responsive drug carrier that can serve both as a magnetic resonance imaging (MRI) and photoacoustic contrast agent, under preclinical settings, and as a type of photothermal therapy. Its hydrophilic nature facilitates biocompatibility. FGO as a broad wavelength absorber, with high charge transfer and strong non-linear scattering is optimal for NIR laser-induced hyperthermia.

Prashanti Jeyamohan, Takashi Hasumura, Yutaka Nagaoka, Yasuhiko Yoshida, Toru Maekawa, D Sakthi Kumar Bio-Nano Electronics Research Centre, Graduate School of Interdisciplinary New Science, Toyo University, Kawagoe, Japan Abstract: The photothermal effect of single-walled carbon nanotubes (SWCNTs) in combination with the anticancer drug doxorubicin (DOX) for targeting and accelerated destruction of breast cancer cells is demonstrated in this paper. A targeted drug-delivery system was developed for selective killing of breast cancer cells with polyethylene glycol biofunctionalized and DOX-loaded SWCNTs conjugated with folic acid. In our work, in vitro drug-release studies showed that the drug (DOX) binds at physiological pH (pH 7.4) and is released only at a lower pH, ie, lysosomal pH (pH 4.0), which is the characteristic pH of the tumor environment. A sustained release of DOX from the SWCNTs was observed for a period of 3 days. SWCNTs have strong optical absorbance in the near-infrared (NIR) region. In this special spectral window, biological systems are highly transparent. Our study reports that under laser irradiation at 800 nm, SWCNTs exhibited strong light–heat transfer characteristics. These optical properties of SWCNTs open the way for selective photothermal ablation in cancer therapy. It was also observed that internalization and uptake of folate-conjugated NTs into cancer cells was achieved by a receptor-mediated endocytosis mechanism. Results of the in vitro experiments show that laser was effective in destroying the cancer cells, while sparing the normal cells. When the above laser effect was combined with DOX-conjugated SWCNTs, we found enhanced and accelerated killing of breast cancer cells. Thus, this nanodrug-delivery system, consisting of laser, drug, and SWCNTs, looks to be a promising selective modality with high treatment efficacy and low side effects for cancer therapy. Keywords: cancer, nanotherapy, SWCNTs, targeted drug delivery, photothermal therapy

Alzheimer's disease is a growing concern in the modern world. As the currently available medications are not very promising, there is an increased need for the fabrication of newer drugs. Curcumin is a plant derived compound which has potential activities beneficial for the treatment of Alzheimer's disease. Anti-amyloid activity and anti-oxidant activity of curcumin is highly beneficial for the treatment of Alzheimer's disease. The insolubility of curcumin in water restricts its use to a great extend, which can be overcome by the synthesis of curcumin nanoparticles. In our work, we have successfully synthesized water-soluble PLGA coated- curcumin nanoparticles and characterized it using different techniques. As drug targeting to diseases of cerebral origin are difficult due to the stringency of blood-brain barrier, we have coupled the nanoparticle with Tet-1 peptide, which has the affinity to neurons and possess retrograde transportation properties. Our results suggest that curcumin encapsulated-PLGA nanoparticles are able to destroy amyloid aggregates, exhibit anti-oxidative property and are non-cytotoxic. The encapsulation of the curcumin in PLGA does not destroy its inherent properties and so, the PLGA-curcumin nanoparticles can be used as a drug with multiple functions in treating Alzheimer's disease proving it to be a potential therapeutic tool against this dreaded disease.

We developed a label-free method for a determination of the number of biomolecules attached to individual cells by measuring the electrophoretic mobility of the cells in a microchannel. The surface of a biological cell, which is dispersed in aqueous solution, is normally electrically charged and the charge quantity at the cell's surface is slightly changed once antibody molecules are attached to the cell, based on which we detect the attachment of antibody molecules to the surface of individual red blood cells by electrophoretic mobility measurement. We also analyzed the number of antibody molecules attached to the cell's surface using a flow cytometer. We found that there is a clear correlation between the number of antibody molecules attached to the individual cells and the electrophoretic mobility of the cells. The present technique may well be utilized not only in the field of cell biology but also in the medical and pharmaceutical industries.

Poly (ethylene terephthalate) (PET) was surface modified by plasma polymerization of acetobromo-α-D-glucose (ABG) at different radio frequency (RF) powers. Plasma polymerization was carried out by vaporizing ABG in the powder form by heating at 135°C. Surface modification resulted in improved hydrophilicity and smoothness of the surface especially at low RF powers (30—50 W), but at high RF powers, the surface was found to be etched and the hydrophilicity decreased as evidenced by atomic force microscopy (AFM) and contact angle measurements. The plasma polymerized ABG film was found to be extensively cross-linked as evidenced by its insolubility in water. Infra red (IR) and X-ray photoelectron spectroscopy (XPS) were employed to characterize the plasma polymerized ABG films. IR studies revealed that at lower RF powers, polymerization was taking place mainly by breaking up of acetoxy group while retaining the ring structures to a major extent during the polymerization process whereas at high RF powers, the rupture of ring structures was indicated. XPS indicated a reduction in the percentage of oxygen in the polymers going from low to high RF powers suggestive of complete destruction of the acetoxy group at high RF powers. Cross-cut tests showed excellent adhesive properties of the plasma polymerized ABG films onto PET. Static platelet adhesion tests using platelet rich human plasma showed significantly reduced adhesion of platelets onto modified PET surface as evidenced by scanning electron microscopy. Polymerization of glucose and its derivatives using RF plasma has not been reported so far and the preliminary results reported in this study shows that this could be an interesting approach in the surface modification of biomaterials.

Poly(ethylene glycol) (PEG) was ‘polymerized’ onto poly(ethylene terephthalate) (PET) surface by radio frequency (RF) plasma polymerization of PEG (average molecular weight 200 Da) at a monomer vapour partial pressure of 10 Pa. Thin films strongly adherent onto PET could be produced by this method. The modified surface was characterized by infra red (IR) spectroscopy, scanning electron microscopy (SEM), atomic force microscopy (AFM), cross-cut test, contact angle measurements and static platelet adhesion studies. The modified surface, believed to be extensively cross-linked, however showed all the chemical characteristics of PEG. The surface was found to be highly hydrophilic as evidenced by an interfacial free energy of about 0.7 dynes/cm. AFM studies showed that the surface of the modified PET became smooth by the plasma polymerized deposition. Static platelet adhesion studies using platelet rich plasma (PRP) showed considerably reduced adhesion of platelets onto the modified surface by SEM. Plasma ‘polymerization’ of a polymer such as PEG onto substrates may be a novel and interesting strategy to prepare PEG-like surfaces on a variety of substrates since the technique allows the formation of thin, pin-hole free, strongly adherent films on a variety of substrates.

Nano-hollow polymer shells, especially those polymers which are FDA approved, have captured the attention of many researchers and scientists in the field of pharmaceutical and medical therapeutics. In the field of controlled drug/gene release, nano-capsules in colloidal solutions, i.e. particles with hollow piths, play an important role in cargo encapsulation. These nanoparticles are synthesized using a variety of procedures such as emulsion polymerization, phase separation, crosslinking of micelles, inner core etching and self-assembly. Our work proposes a novel route to prepare hollow PLGA (poly (lactic-co-glycolic) acid) nanoparticles (HNPs), which showed increased drug-encapsulation and release efficiency. The simple emulsion solvent evaporation technique was adopted to synthesize nano-hollow shells of FDA approved polymer PLGA using only one organic phase. The hollow characteristics of nanoparticles were studied using scanning electron microscopy (SEM), transmission electron microscopy (TEM) and confocal microscopy analysis. The particle size was analyzed by dynamic light scattering (DLS). Nanoparticles drug loading, encapsulation and release efficiency in vitro were assessed by ultraviolet spectroscopy. The developed nanoparticles were hollow and spherical in shape and approximately 80 nm in size. The drug encapsulation efficiency is 99.4% and the drug was released in a controllable manner during in vitro analysis.