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    Finger-operated pumping platform for microfluidic preparation of nanoparticles
    (Springer, 2024) Azmeer, Ahmed; Kanan, Ibraheem; Husseini, Ghaleb; Abdelgawad, Mohammad
    Microfluidic preparation of nanoparticles (NPs) offers many advantages over traditional bench-top preparation techniques, including better control over particle size and higher uniformity. Although many studies have reported the use of low-cost microfluidic chips for nanoparticle synthesis, the technology is still expensive due to the high cost of the pumps needed to generate the required flows inside microchannels. Here, we present a low-cost finger-operated constant-pressure pumping platform capable of generating pressures as high as 120 kPa using finger-operated pumping caps that can be attached to any pop bottle. The platform costs around $208 and enables the generation of flow rate ratios (FRR) of up to 47:1 for the continuous flow synthesis of NPs. The pump has a resolution of 500 Pa per stroke and exhibits stable pressures for up to a few hours. To show the functionality of the proposed pump, we used it to prepare pegylated liposomes and poly lacticco-glycolic acid (PLGA) nanoparticles with sizes ranging from 47 nm to 250 nm with an average polydispersity of 20% using commercially available micromixer chips and in-house made hydrodynamic flow focusing devices. We believe this platform will render microfluidic preparation of NPs accessible to any laboratory with minimal capabilities.
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    Production of Targeted Estrone Liposomes Using a Herringbone Micromixer
    (IEEE, 2024) Agam, Mohamed Abdalla; Paul, Vinod; Abdelgawad, Mohammad; Husseini, Ghaleb
    Liposomes are spherical vesicles formed from bilayer lipid membranes that are extensively used in targeted drug delivery as nanocarriers to deliver therapeutic reagents to specific tissues and organs in the body. Recently, we have reported using estrone as an endogenous ligand on doxorubicin-encapsulating liposomes to target estrogen receptor (ER)-positive breast cancer cells. Estrone liposomes were synthesized using the thin-film hydration method, which is a long, arduous, and multistep process. Here, we report using a herringbone micromixer to synthesize estrone liposomes in a simple and rapid manner. A solvent stream containing the lipids was mixed with a stream of phosphate buffer saline (PBS) inside a microchannel integrated with herringbone-shaped ridges that enhanced the mixing of the two streams. The small scale involved enabled rapid solvent exchange and initiated the self-assembly of the lipids to form the required liposomes. The effect of different parameters on liposome size, such as the ratio between the flow rate of the solvent and the buffer solutions (FRR), total flow rate, lipid concentrations, and solvent type, were investigated. Using this commercially available chip, we obtained liposomes with a radius of 66.1 ± 11.2 nm (mean ± standard deviation) and a polydispersity of 22% in less than 15 minutes compared to a total of ∼ 11 hours using conventional techniques. Calcein was encapsulated inside the prepared liposomes as a model drug and was released by applying ultrasound at different powers. The size of the prepared liposomes was stable over a period of one month. Overall, using microfluidics to synthesize estrone liposomes simplified the procedure considerably and improved the reproducibility of the resulting liposomes.
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    Microwave-Responsive Metal-Organic Frameworks (MOFs) for Enhanced In Vitro Controlled Release of Doxorubicin
    (MDPI, 2024) Fatima, Syeda Fiza; Sabouni, Rana; Husseini, Ghaleb; Paul, Vinod; Gomaa, Hassan
    Metal-organic frameworks (MOFs) are excellent candidates for a range of applications because of their numerous advantages, such as high surface area, porosity, and thermal and chemical stability. In this study, microwave (MW) irradiation is used as a novel stimulus in vitro controlled release of Doxorubicin (DOX) from two MOFs, namely Fe-BTC and MIL-53(Al), to enhance drug delivery in cancer therapy. DOX was encapsulated into Fe-BTC and MIL-53(Al) with drug-loading efficiencies of up to 67% for Fe-BTC and 40% for MIL-53(Al). Several characterization tests, including XRD, FTIR, TGA, BET, FE-SEM, and EDX, confirmed both MOF samples’ drug-loading and -release mechanisms. Fe-BTC exhibited a substantial improvement in drug-release efficiency (54%) when exposed to microwave irradiation at pH 7.4 for 50 min, whereas 11% was achieved without the external modality. A similar result was observed at pH 5.3; however, in both cases, the release efficiencies were substantially higher with microwave exposure (40%) than without (6%). In contrast, MIL-53(Al) exhibited greater sensitivity to pH, displaying a higher release rate (66%) after 38 min at pH 5.3 compared to 55% after 50 min at pH 7.4 when subjected to microwave irradiation. These results highlight the potential of both MOFs as highly heat-responsive to thermal stimuli. The results of the MTT assay demonstrated the cell viability across different concentrations of the MOFs after two days of incubation. This suggests that MOFs hold promise as potential candidates for tumor targeting. Additionally, the fact that the cells maintained their viability at different durations of microwave exposure confirms that the latter is a safe modality for triggering drug release from MOFs.
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    Technological Tools to Learn and Teach Mathematics and Statistics
    (Association for Computer Science and Telecommunications, 2012-02) Mesanovic, Mujo
    The blended learning method of teaching could be applied within the learning of mathematics and statistics. There are many different ways to obtain such learning, however one of the beneficial ways is to use MyLab and Mastering. MyLab and Mastering is blackboard website managed by the Pearson Publication Company which is used to enhance student learning in mathematics and statistics embedded within the current technological world. This paper describes the use of the MyLab and Mastering website from three points of view: instructor, students and administrative. This paper portrays the results of a recent study, where 120 students were enrolled in mathematics and statistics classes and used MyLab to improve their learning outcomes. Result of the case study are reported and analyzed. In addition suggestions are provided how to establish almost cost-free distance learning environments for mathematics and statistics.
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    Recent Advancements in Bone Tissue Engineering: Integrating Smart Scaffold Technologies and Bio-Responsive Systems for Enhanced Regeneration
    (MDPI, 2024) Percival, Kelly M.; Paul, Vinod; Husseini, Ghaleb
    In exploring the challenges of bone repair and regeneration, this review evaluates the potential of bone tissue engineering (BTE) as a viable alternative to traditional methods, such as autografts and allografts. Key developments in biomaterials and scaffold fabrication techniques, such as additive manufacturing and cell and bioactive molecule-laden scaffolds, are discussed, along with the integration of bio-responsive scaffolds, which can respond to physical and chemical stimuli. These advancements collectively aim to mimic the natural microenvironment of bone, thereby enhancing osteogenesis and facilitating the formation of new tissue. Through a comprehensive combination of in vitro and in vivo studies, we scrutinize the biocompatibility, osteoinductivity, and osteoconductivity of these engineered scaffolds, as well as their interactions with critical cellular players in bone healing processes. Findings from scaffold fabrication techniques and bio-responsive scaffolds indicate that incorporating nanostructured materials and bioactive compounds is particularly effective in promoting the recruitment and differentiation of osteoprogenitor cells. The therapeutic potential of these advanced biomaterials in clinical settings is widely recognized and the paper advocates continued research into multi-responsive scaffold systems.

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