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This study presents LHRH conjugated drug delivery via a magnetite nanoparticle-modified microporous Poly-Di-Methyl-Siloxane (PDMS) system for the targeted suppression of triple-negative breast cancer cells. First, the MNP-modified PDMS devices are fabricated before loading with targeted and untargeted cancer drugs. The release kinetics from the devices are then studied before fitting the results to the Korsmeyer–Peppas model. Cell viability and cytotoxicity assessments are then presented using results from the Alamar blue assay. Apoptosis induction is then elucidated using flow cytometry. The in vitro drug release studies demonstrated a sustained and controlled release of unconjugated drugs (Prodigiosin and paclitaxel) and conjugated drugs [LHRH conjugated paclitaxel (PTX+LHRH) and LHRH-conjugated prodigiosin (PG+LHRH)] from the magnetite nanoparticle modified microporous PDMS devices for 30 days at 37 °C, 41 °C, and 44 °C. At 24, 48, 72, and 96 h, the groups loaded with conjugated drugs (PG+LHRH and PTX+LHRH) had a significantly higher (p < 0.05) percentage cell growth inhibition than the groups loaded with unconjugated drugs (PG and PTX). Additionally, throughout the study, the MNP+PDMS (without drug) group exhibited a steady rise in the percentage of cell growth inhibition. The flow cytometry results revealed a high incidence of early and late-stage apoptosis. The implications of the results are discussed for the development of biomedical devices for the localized and targeted release of cancer drugs that can prevent cancer recurrence following tumor resection. [ABSTRACT FROM AUTHOR]

This article presents silica nanoparticles for the sustained release of AMACR antibody‐conjugated and free doxorubicin (DOX) for the inhibition of prostate cancer cell growth. Inorganic MCM‐41 silica nanoparticles were synthesized, functionalized with phenylboronic acid groups (MCM‐B), and capped with dextran (MCM‐B‐D). The nanoparticles were then characterized using Fourier‐transform infrared spectroscopy, scanning electron microscopy, transmission electron microscopy, zeta potential analysis, nitrogen sorption, X‐ray diffraction, and thermogravimetric analysis, before exploring their potential for drug loading and controlled drug release. This was done using a model prostate cancer drug, DOX, and a targeted prostate cancer drug, α‐Methyl Acyl‐CoA racemase (AMACR) antibody‐conjugated DOX, which attaches specifically to AMACR proteins that are overexpressed on the surfaces of prostate cancer cells. The kinetics of sustained drug release over 30 days was then studied using zeroth order, first order, second order, Higuchi, and the Korsmeyer–Peppas models, while the thermodynamics of drug release was elucidated by determining the entropy and enthalpy changes. The flux of the released DOX was also simulated using the COMSOL Multiphysics software package. Generally, the AMACR antibody‐conjugated DOX drug‐loaded nanoparticles were more effective than the free DOX drug‐loaded formulations in inhibiting the growth of prostate cancer cells in vitro over a 96 h period. The implications of the results are then discussed for the development of drug‐eluting structures for the localized and targeted treatment of prostate cancer. [ABSTRACT FROM AUTHOR]

Low- and middle-income countries have tremendous potential for renewable energy production, including production of renewable carbon from locally prolific crops. In this work, bamboo endemic to West Africa (Bambusa vulgaris) was studied as a feedstock for the production of renewable sugars as the gateway to the local production of biofuels and bio-based chemical products. The effectiveness of delignification and amorphization pretreatments was evaluated, with the observation that quantitative (97 ± 4%) sugar yields could be obtained with a rapid initial hydrolysis rate (82 ± 4 mg g−1 h−1) but only when amorphization was performed following delignification. Experimental measurements and further characterization using 13C solid state nuclear magnetic resonance (NMR) helped establish the importance of amorphization and delignification and explained why the order of these treatments determined their effectiveness. The economics of the bamboo-based process were compared with those projected for corn stover, selected as a well-studied benchmark crop. Because of the higher bamboo growth rate compared with corn stover and the effectiveness of the pretreatment, the projected net present value (NPV) of the bamboo biorefinery was positive ($190 MM, U.S.), whereas the corn biorefinery projected to negative NPV (−$430 MM, U.S.). A socially sustainable framework for deployment of a bamboo biorefinery in a low- or middle-income economy was then proposed, guided by the principle of local ownership and stakeholder buy-in. The findings presented here motivate further investment in development of bamboo cultivation and conversion to sugars as a rapid route to decarbonization of low- and middle-income economies. [ABSTRACT FROM AUTHOR]

This article presents the correlation of creep and viscoelastic properties to the cytoskeletal structure of both tumorigenic and non‐tumorigenic cells. Unique shear assay and strain mapping techniques were used to study the creep and viscoelastic properties of single non‐tumorigenic and tumorigenic cells. At least 20 individual cells, three locations per cell, were studied. From the results, lower densities in the volume of actin, and keratin 18 structures were observed with the progression of cancer and were correlated to the increased creep rates and reduced mechanical properties (Young's moduli and viscosities) of tumorigenic (MDA‐MB‐231) cells. The study reveals significant differences between the creep and viscoelastic properties of non‐tumorigenic breast cells versus tumorigenic cells. The variations in the creep strain rates are shown to be well characterized by lognormal distributions, while the statistical variations in the viscoelastic properties are well‐described by normal distributions. The implications of the results are discussed for the study of discrete cell behaviors, strain and viscoelastic responses of the cell, and the role of cell cytoskeleton in the onset and progression of cancers. [ABSTRACT FROM AUTHOR]

This paper examines the effects of hydroxyapatite (HA) and bone- particle (BP) doping on the removal of fluoride and bacteria by ceramic water filters (CWFs). The CWFs were produced by mixing clay, sieved sawdust, and either HA or BPs in a weight ratio of 30:50:20 and sintered at 850°C or 900°C to produce micro-/ nano-porous structures that remove microbial pathogens (by geometric occlusion) and fluoride (by adsorption) from contaminated water. The HA-doped filters exhibited similar flow characteristics to the BP-doped filters. However, BP-doped CWFs were more effective in removing fluoride and microbial pathogens (such as E. coli) from contaminated water than HA-doped filters. The water flow rates and fluoride removal depended on sintering temperature, with CWFs sintered at 850°C enabling faster flow rates of 2.2Lh−1 and higher fluoride removal of 2.74 mol.cm−2 than the CWFs sintered at 900°C. Fluoride removal by the HA- and BP-doped filters was well characterized by Freundlich isotherms that reveal the occurrence of spontaneous but heterogeneous adsorption. The implications of the results are discussed for the design of point-of-use CWFs for the removal of fluoride and microbial pathogens. [ABSTRACT FROM AUTHOR]

This paper presents in vitro studies of the sustained release of Annona muricata leaf extracts (AME) from hybrid electrospun fibers for breast cancer treatment. Electrospun hybrid scaffolds were fabricated from crude AME extracts, poly(lactic‐co‐glycolic acid)/gelatin (PLGA/Ge) and pluronic F127. The physicochemical properties of the AME extract and scaffolds were studied. The antiproliferative effects of the scaffolds were also assessed on breast cancer (MCF‐7 and MDA‐MB‐231) and non‐tumorigenic breast (MCF10A) cell lines. Scanning electron microscope micrographs revealed a random network of micro‐ and submicron fibers. In vitro drug release profiles, governed by quasi‐Fickian diffusion at pH 7.4 and non‐Fickian super case II at pH 6.7, showed initial burst AME release from the PLGA/Ge‐AME and PLGA/Ge‐F127/AME fibers at pH 7.4, and burst release from PLGA/Ge‐F127/AME (not observed from PLGA/Ge‐AME) at pH 6.7. Then, a slower, sustained release of the remaining AME from the fibers, attributed to the onset of degradation of the PLGA/Ge backbone, was observed for the next 72 hr. The cumulative release of AME was 89.33 ± 0.73% (PLGA/Ge‐AME) and 51.17 ± 7.96% (PLGA/Ge‐F127/AME) at pH 7.4, and 9.27 ± 2.3% and 73.5 ± 4.5%, respectively, at pH 6.7. Pluronic F127 addition increased the drug loading capacity and prolonged the sustained AME release from the fibers. The released AME significantly inhibited the in vitro growth of the breast cancer cells more than the non‐tumorigenic cells, due to the induction of apoptosis, providing evidence for using pluronic F127‐containing electrospun fibers for sustained and localized AME delivery to breast cancer cells. [ABSTRACT FROM AUTHOR]

This article presents the results of cell–surface interactions on polydimethylsiloxane (PDMS)‐based substrates coated with nanoscale gold (Au) thin films. The surfaces of PDMS and PDMS–magnetite (MNP)‐based substrates were treated with UV‐ozone, prior to thermal vapor deposition (sputter‐coated) of thin films of titanium (Ti) onto the substrates to improve the adhesion of Au coatings. The thin layer of Ti was thermally evaporated to improve interfacial adhesion, which was enhanced by a 40‐nm thick film microwrinkled/buckled wavy layer of Au, that was coated to enhance cell–surface interactions and protein absorption. Cell–surface interactions were studied on the hybrid surfaces using a combination of optical and fluorescence microscopy. Consequently, cell proliferation and surface cytotoxicity (of the sputter‐coated PDMS surfaces) were elucidated by characterizing the metabolic activity in the presence of breast cancer and normal breast cells. The photothermal conversion efficiency associated with laser–materials interactions with the PDMS/PDMS–magnetite‐based composites was shown to have an optimum efficiency of ~31.8%. The implications of the results are discussed for potential applications of PDMS nanocomposites in implantable biomedical devices. [ABSTRACT FROM AUTHOR]