In vitro evaluation of PEGylated mesoporous MgFe2O4 magnetic nanoassemblies (MMNs) for chemo-thermal therapy

A size tunable synthesis of mesoporous MgFe2O4 magnetic nanoassemblies (MMNs) through a PEG-diacid mediated polyol method is reported. The PEG-diacid coated MMNs exhibit a significant specific surface area of 92 m(2) g (1) and saturation magnetization of 57 emu g (1). These MMNs exhibit a very good colloidal stability in PBS (pH 7.4) with nonappreciable cytotoxicity in mouse fibroblast (L929) and cervical cancer (HeLa) cells. We demonstrate the potential of MMNs as an integrated nanosystem for drug delivery and magnetic hyperthermia (MHT) through in vitro studies. 80% loading efficiency of doxorubicin (DOX) has been achieved due to the highly negative surface charge and mesoporous nature of MMNs. It is observed that 65-70% of HeLa cells undergo apoptosis through DNA fragmentation after 24 h of incubation with DOX loaded MMNs. MHT alone induces the death of 40-45% of cells, whereas the synergistic effect of a combination of DOX and MHT leads to the death of about 90% of cells. Our results show that MHT significantly increases the therapeutic efficacy of DOX to induce more apoptosis in cancer cells. Hence, a combination of MHT with chemotherapy makes MMNs a powerful multimodal system for synergistic chemo-thermal cancer therapy

Anammox: A sustainable technology for nitrogen removal and water recycling

© 2016 American Society of Civil Engineers. This chapter discusses developments in the anammox process, since its discovery, including identification of responsible microbes and their physiology, potential process inhibitors, reactor types used, and application to treat different wastewater. Anammox bacteria are coccoid bacteria with an average diameter ranging between 800 and 1100 nm. Anammox bacteria are chemoautotrophic bacteria and use CO2 as the main inorganic carbon source to oxidize ammonium to nitrogen gas using nitrite as the electron acceptor. Ammonium and nitrite are the two substrates for anammox bacteria. The absence of nitrite in wastewater limits the direct application of the anammox process. Applications of anammox or its related processes, such as SHARON-Anammox, CANON, or SNAD have been tested to treat real world wastewaters by many researchers in lab scale reactors. Anammox combined with partial nitrification has been identified as the most efficient, economical, and environmentally friendly nitrogen removal method in recent years

Wastewater: A potential resource of energy

© 2016 American Society of Civil Engineers. This chapter discusses the energy production potential of different wastewater sources and various treatment processes with an aim of establishing sustainable energy management systems. The refractory fraction of wastewater can be converted to energy through thermal, chemical, or electrical processes. The importance of knowing the potential energy available lies in the choice of treatment methods so that most of the energy can be recovered. Some wastes that may be high in energy value, such as halogenated wastes, may be unsuitable or unattractive to some treatment methods. The chapter discusses several systems for energy recovery with simultaneous treatment of wastewater. Some of the systems include anaerobic treatment, microbial fuel cell (MFC), simultaneous algal biomass production, and wastewater treatment. The adverse environmental impacts associated with anaerobic treatment or MFC are mainly because of electricity consumption in the various process units and transportation/disposal of biosolids

Theranostic fluorescent silica encapsulated magnetic nanoassemblies for in vitro MRI imaging and hyperthermia

This article reports the synthesis of manganese ferrite nano-assemblies (MNAs) encapsulated with fluorescent silica shell and demonstrates their applicability for magnetic hyperthermia, optical and T-2 contrast MRI imaging with HeLa cancer cells. The MNAs were encapsulated by a double layer of silica shell through a two-step sol-gel process. The inner silica shell contains rhodamine-B isothiocyanate (RITC) dye, whereas the outer silica layer is without RITC-dye, helps to prevent photo-bleaching and increase photo-luminance. MNAs@Dye-SiO2@SiO2 exhibited a high magnetization of 90.43 emu g(-1) with a remarkably high r(2) value of 598 +/- 2 mM(-1) s(-1) (Mn + Fe). The cellular uptake of MNAs@DyeSiO(2)@SiO2 was observed by the presence of fluorescent red granulated spots in the cytoplasm of HeLa cells, confirming its efficacy for optical imaging. High transverse relaxivities r(2) (darkening effect) were observed in HeLa cells incubated with MNAs@Dye-SiO2@SiO2 in comparison to HeLa cells without particles. An 80-85% cell death was achieved on induction of magnetic hyperthermia with HeLa cells at the lowest Hf factor value (3.3 +/- 109 A m(-1) s(-1)). Our results show MNAs@Dye-SiO2@SiO2 as a novel multifunctional theranostic nanoprobe, which can realize its applicability for diagnostic and real time monitoring the efficacy of ongoing cancer therapy