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The hydrolysis–condensation reaction of TiO 2 was adapted to the phase inversion temperature (PIT)-nano-emulsion method as a low energy approach to gain control over the size and phase purity of the resulting metal oxide particles. Three different PIT-nano-emulsion syntheses were designed, each one intended to isolate high purity rutile, anatase, and brookite phase particles. Three different emulsion systems were prepared, with a pH of either strongly acidic (H 2 O : HNO 3 , pH ∼0.5), moderately acidic (H 2 O : isopropanol, pH ∼4.5), or alkaline (H 2 O : NaOH, pH ∼12). PIT-nano-emulsion syntheses of the amorphous TiO 2 particles were conducted under these conditions, resulting in average particle diameter distributions of ∼140 d nm (strongly acidic), ∼60 d nm (moderately acidic), and ∼460 d nm (alkaline). Different thermal treatments were performed on the amorphous particles obtained from the PIT-nano-emulsion syntheses. Raman spectroscopy and powder X-ray diffraction (PXRD) were employed to corroborate that the thermally treated particles under H 2 O : HNO 3 (at 850 °C), H 2 O : NaOH (at 400 °C), and H 2 O : isopropanol (at 200 °C) yielded highly-pure rutile, anatase, and brookite phases, respectively. Herein, an experimental approach based on the PIT-nano-emulsion method is demonstrated to synthesize phase-controlled TiO 2 particles with high purity employing fewer toxic compounds, reducing the quantity of starting materials, and with a minimum energy input, particularly for the almost elusive brookite phase. 

Coordination of clinically employed bisphosphonate, risedronate (RISE), to bioactive metals, Ca2+, Mg2+, and Zn2+, allowed the formation of bisphosphonate-based coordination complexes (BPCCs). Three RISE-based BPCCs, RISE-Ca, RISEMg, and RISE-Zn, were produced, and their structures were elucidated by single crystal X-ray difraction. Interestingly, the addition of an auxiliary ligand, etidronic acid (HEDP), resulted in the recrystallized protonated form of the ligand, H-RISE. The pH-dependent structural stability of the RISE-based BPCCs was measured by means of dissolution profles under neutral and acidic simulated physiological conditions (PBS and FaSSGF, respectively). In comparison to RISE (Actonel), the complexes showed a lower equilibrium solubility (∼70−85% in 18−24 h) in PBS, while a higher equilibrium solubility (∼100% in 3 h) in acidic media. The results point to the capacity to release this BP in a pH-dependent manner from the RISE-based BPCCs. Subsequently, the particle size of RISE-Ca was reduced, from 300 μm to ∼350 d.nm, employing the phase inversion temperature (PIT)-nanoemulsion method, resulting in nano-Ca@RISE. Aggregation measurements of nano-Ca@RISE in 1% fetal bovine serum (FBS):H2O was monitored after 24, 48, and 72 h to study the particle size longevity in physiological media, showing that the suspended material has the potential to maintain its particle size over time. Furthermore, binding assays were performed to determine the potential binding of nano-Ca@RISE to the bone, where results show higher binding (~1.7×) for the material to hydroxyapatite (HA, 30%) when compared to RISE (17%) in 1 d. The cytotoxicity efects of nano-Ca@RISE were compared to those of RISE against the human breast cancer MDA-MB-231 and normal osteoblast-like hFOB 1.19 cell lines by dose−response curves and relative cell viability assays in an in vitro setting. The results demonstrate that nano-Ca@RISE signifcantly decreases the viability of MDA-MB-231 with high specifcity, at concentrations ∼2−3× lower than the ones reported employing other third-generation BPs. This is supported by the fact that when normal osteoblast cells (hFOB 1.19), which are part of the tissue microenvironment at metastatic sites, were treated with nano-Ca@RISE no signifcant decrease in viability was observed. This study expands on the therapeutic potential of RISE beyond its antiresorptive activity through the design of BPCCs, specifcally nano-Ca@RISE, that bind to the bone and degrade in a pH-dependent manner under acidic conditions 

Through diversity of composition, sequence, and interfacial structure, hybrid materials greatly expand the palette of materials available to access novel functionality. The NSF Division of Materials Research recently supported a workshop (October 17–18, 2019) aiming to (1) identify fundamental questions and potential solutions common to multiple disciplines within the hybrid materials community; (2) initiate interfield collaborations between hybrid materials researchers; and (3) raise awareness in the wider community about experimental toolsets, simulation capabilities, and shared facilities that can accelerate this research. This article reports on the outcomes of the workshop as a basis for cross-community discussion. The interdisciplinary challenges and opportunities are presented, and followed with a discussion of current areas of progress in subdisciplines including hybrid synthesis, functional surfaces, and functional interfaces. 

Pyrethroid contact insecticides are mainstays of malaria control, but their efficacies are declining due to widespread insecticide resistance inAnophelesmosquito populations, a major public health challenge. Several strategies have been proposed to overcome this challenge, including insecticides with new modes of action. New insecticides, however, can be expensive to implement in low-income countries. Here, we report a simple and inexpensive method to improve the efficacy of deltamethrin, the most active and most commonly used pyrethroid, by more than 10 times againstAnophelesmosquitoes. Upon heating for only a few minutes, the commercially available deltamethrin crystals, form I, melt and crystallize upon cooling into a polymorph, form II, which is much faster acting against fruit flies and mosquitoes. Epidemiological modeling suggests that the use of form II in indoor residual spraying in place of form I would significantly suppress malaria transmission, even in the presence of high levels of resistance. The simple preparation of form II, coupled with its kinetic stability and markedly higher efficacy, argues that form II can provide a powerful, timely, and affordable malaria control solution for low-income countries that are losing protection in the face of worldwide pyrethroid resistance.