Anjana Pandey

Chloroform- and Water-Soluble Sol–Gel Derived (Red) and (Green) Nanophosphors: Synthesis, Characterization, and Surface Modification

Eu⁺⁺⁺ and Tb⁺⁺⁺ ions have been incorporated into nanodimensional yttrium oxide host matrices via a sol-gel process using Y₅O(OPrⁱ)₁₃ as precursor (OPrⁱ = isopropoxy). The as-synthesized white powders have been annealed at different temperatures. Photoluminescence (PL) spectroscopy and X-ray diffraction (XRD) have been used as tools for documenting the characteristics of these powders. For Eu⁺⁺⁺-doped powders, a comparison of the Eu⁺⁺⁺, ⁵D₀rarr⁷F₁, and ⁵D₀rarr⁷F₂ peak intensities in the emission spectra reveals that the dopant ions are occupying unsymmetrical sites in the host yttrium oxide in all the samples. For Tb⁺⁺⁺-doped powders, the characteristic terbium ⁵D₃rarr⁷F_n and ⁵Drarr⁷F_n ( <i>n</i> = 2-6) transitions were visible only in the samples that had been annealed above 500degC. Samples of the doped particle powders were suspended in chloroform by fragmenting the powder with and without sonification under the presence of trioctylphosphine oxide, or a mixture of oleic acid and dioctyl ether. The resulting clear colorless (for Eu⁺⁺⁺ ) and light green translucent (for Tb⁺⁺⁺) solutions of the suspended particles showed red and green luminescence upon UV excitation, respectively. In addition, suspension in water has been achieved by fragmenting the powder in the presence of dichloroacetic acid. Transmission electron micrograph investigation of the soluble particles shows single dispersed particles along with agglomerates. The changes in the luminescence due to fragmentation of the particle powder and due the influence of the surfactant of the suspended colloidal particles are discussed.

Electricity generation in membrane-less single chambered microbial fuel cell

Microbial fuel cells are rapidly growing sustainable technology for energy production. In MFC microbes in anode chamber oxidizes organic compound transferring electrons to anode and protons towards cathode chamber via proton exchange membrane. From anode the electrons passes through an external circuit to cathode chamber and combined with proton to produce water in the presence of oxygen. But the high cost and biofouling of proton exchange membrane limits the practical use of MFCs. The aim of this paper is to present the performance of membrane-less single chambered microbial fuel cells (MFC). The MFC was constructed under anaerobic condition utilizing the synthetic glucose substrate to generate electricity. The biofilm of microbe Bacillus firmus-NMBL-03 over plain graphite electrodes was used as biocatalyst. When operated with an external resistance of 1000 Ω, the MFC produced maximum power density of 0.88 mW/m2 and average power density of 0.19 mW/m2 for 500 hrs. The maximum power density 2.9 mW/m2 at current density 17.7 mA/m2 was observed.

Chloroform- and water-soluble sol-gel derived Eu+++/Y2O3 (red) and Tb+++/Y2O3 (green) nanophosphors: synthesis, characterization, and surface modification.

Eu⁺⁺⁺ and Tb⁺⁺⁺ ions have been incorporated into nanodimensional yttrium oxide host matrices via a sol-gel process using Y₅O(OPrⁱ)₁₃ as precursor (OPrⁱ = isopropoxy). The as-synthesized white powders have been annealed at different temperatures. Photoluminescence (PL) spectroscopy and X-ray diffraction (XRD) have been used as tools for documenting the characteristics of these powders. For Eu⁺⁺⁺-doped powders, a comparison of the Eu⁺⁺⁺, ⁵D₀rarr⁷F₁, and ⁵D₀rarr⁷F₂ peak intensities in the emission spectra reveals that the dopant ions are occupying unsymmetrical sites in the host yttrium oxide in all the samples. For Tb⁺⁺⁺-doped powders, the characteristic terbium ⁵D₃rarr⁷F_n and ⁵Drarr⁷F_n ( <i>n</i> = 2-6) transitions were visible only in the samples that had been annealed above 500degC. Samples of the doped particle powders were suspended in chloroform by fragmenting the powder with and without sonification under the presence of trioctylphosphine oxide, or a mixture of oleic acid and dioctyl ether. The resulting clear colorless (for Eu⁺⁺⁺ ) and light green translucent (for Tb⁺⁺⁺) solutions of the suspended particles showed red and green luminescence upon UV excitation, respectively. In addition, suspension in water has been achieved by fragmenting the powder in the presence of dichloroacetic acid. Transmission electron micrograph investigation of the soluble particles shows single dispersed particles along with agglomerates. The changes in the luminescence due to fragmentation of the particle powder and due the influence of the surfactant of the suspended colloidal particles are discussed.

An Overview on Advances in the Nanocarriers Drug Delivery Systems

The unceasing efforts and improvement of drug delivery systems (DDSs) have been broadly researched to maximize therapeutic efficacy while curtailing undesirable side effects. Nanoparticle technology was recently shown to hold great promise for drug delivery applications in nanomedicine due to its favorable properties, such as better encapsulation, bioavailability, control release, and lower toxic effects. Regardless of the great progress in nanomedicine, there remain many limitations prior to widely being accepted for medical application. To overcome these limitations, advanced nanoparticles for drug delivery have been developed to enable the spatially and temporally controlled release of drugs in response to specific stimuli at disease sites. An ideal drug delivery system should be able to localize a drug specifically and directly to its target. This is particularly important when drugs made by traditional manufacturing methods are hydrophobic and their solvents are toxic. Nanotechnology promises to improve drug delivery system design and targeting. Nanostructured drugs or delivery carriers allow the continuous and controlled release of therapeutic drugs to maintain drug levels to a desired extent. The size of nanoparticles ranges from 10 to 200 nm, about the size of a protein. Because of their small size, nanoparticles can readily interact with biomolecules on the cell surface or inside cell allowing these nanoparticles to penetrate tissues in depth with a high level of specificity. This chapter discusses an overview of nanoparticulate systems that can be used as a potential drug delivery carriers and focuses on the potential applications of nanoparticles in various biomedical fields for improving human health care.

Applications of Nano-based Novel Drug Delivery Systems in Herbal Medicine-Mediated Cancer Therapy

Nanotechnology is a fast-growing field with numerous applications in the field of medical science. One such application comprises nanoparticle biosynthesis from plant extracts and their compounds with their potential applications in cancer therapy. These plant-based nanoparticles have been observed to be effective against various types of cancerous cells both in vitro and animal models. Another application of nanotechnology is the herbal therapeutics comprising the use of novel nano-based drug delivery systems in the treatment of cancer. These novel drug delivery systems aid in increasing the therapeutic value and bioavailability of the herbal medicine. The application of nanoherbal formulations as novel drug delivery systems (NDDS) is more valuable as compared to other therapies. These novel drug delivery systems include phytosomes, liposomes, microsphere, nanocapsules, ethosomes, transfersomes, nanoemulsions, and polymeric nanoparticles. The effectiveness of these different plant-based nanodrug delivery systems has been studied against various cancer types. These alternative drug delivery systems help in increasing the efficiency of a drug delivery and safeguard the drug from metabolic processes alongside its sustained delivery, proper distribution, and protection from physical and chemical deterioration. In addition, they reduce the possible side effects of the drugs. In spite of the advancements, cancer endures to be a predominant and fatal disease. This has led to the increased use of nano-based anticancer drugs and their delivery systems, also known as nanotherapies against tumors due to their ability of site-specific targeting and multifunctionality. In this chapter, recent advancements in application of plant-based nanomaterials in cancer therapy and impending strategies are discussed.

Chloroform- and Water-Soluble Sol–Gel Derived

Eu⁺⁺⁺ and Tb⁺⁺⁺ ions have been incorporated into nanodimensional yttrium oxide host matrices via a sol-gel process using Y₅O(OPrⁱ)₁₃ as precursor (OPrⁱ = isopropoxy). The as-synthesized white powders have been annealed at different temperatures. Photoluminescence (PL) spectroscopy and X-ray diffraction (XRD) have been used as tools for documenting the characteristics of these powders. For Eu⁺⁺⁺-doped powders, a comparison of the Eu⁺⁺⁺, ⁵D₀rarr⁷F₁, and ⁵D₀rarr⁷F₂ peak intensities in the emission spectra reveals that the dopant ions are occupying unsymmetrical sites in the host yttrium oxide in all the samples. For Tb⁺⁺⁺-doped powders, the characteristic terbium ⁵D₃rarr⁷F_n and ⁵Drarr⁷F_n ( <i>n</i> = 2-6) transitions were visible only in the samples that had been annealed above 500degC. Samples of the doped particle powders were suspended in chloroform by fragmenting the powder with and without sonification under the presence of trioctylphosphine oxide, or a mixture of oleic acid and dioctyl ether. The resulting clear colorless (for Eu⁺⁺⁺ ) and light green translucent (for Tb⁺⁺⁺) solutions of the suspended particles showed red and green luminescence upon UV excitation, respectively. In addition, suspension in water has been achieved by fragmenting the powder in the presence of dichloroacetic acid. Transmission electron micrograph investigation of the soluble particles shows single dispersed particles along with agglomerates. The changes in the luminescence due to fragmentation of the particle powder and due the influence of the surfactant of the suspended colloidal particles are discussed.