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  1. Abstract

    The effective removal of complex pollutants is extremely challenging for environmental and material science, especially pollutants including detergents and pesticides do not decompose or degrade in the aquatic environment which cannot be easily removed. Here, a novel biocompatible superparamagnetic nanocomposite integrating the advantages of porous silicon nanoparticles is developed, the chelation ability of chitosan, and graphene‐oxide‐iron that can simultaneously adsorb complex hydrophobic and hydrophilic pollutants on their internal and external surfaces which have significantly improved pollutant removal efficiency over the current existing methods. A porous silicon nanoparticle (PSi) conjugated magnetite‐chitosan‐reduced graphene oxide (MCRGO) nanoparticles (PSi‐MCRGO) are synthesized for complete removal of detergent, pesticide, and toxic heavy metals cadmium and lead ions from water at a favorable room temperature. The adsorption behavior of the nanocomposites fits well with the Freundlich isotherm and pseudo‐second‐order kinetics model by adsorption mechanism. Moreover, the fresh and recycled nanocomposites are easily separated by an external magnetic field for reusability due to super magnetite response and show high binding capacity for toxic heavy metal ions. Furthermore, the nanocomposites are biocompatible and reusable, and for the fourth time, recycled nanocomposites can completely remove toxic heavy metals. Overall, the novel nanocomposites completely remove complex pollutants which hold great potential for real water treatment.

     
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  2. Effective cancer therapies often demand delivery of combinations of drugs to inhibit multidrug resistance through synergism, and the development of multifunctional nanovehicles with enhanced drug loading and delivery efficiency for combination therapy is currently a major challenge in nanotechnology. However, such combinations are more challenging to administer than single drugs and can require multipronged approaches to delivery. In addition to being stable and biodegradable, vehicles for such therapies must be compatible with both hydrophobic and hydrophilic drugs, and release drugs at sustained therapeutic levels. Here, we report synthesis of porous silicon nanoparticles conjugated with gold nanorods [composite nanoparticles (cNPs)] and encapsulate them within a hybrid polymersome using double-emulsion templates on a microfluidic chip to create a versatile nanovehicle. This nanovehicle has high loading capacities for both hydrophobic and hydrophilic drugs, and improves drug delivery efficiency by accumulating at the tumor after i.v. injection in mice. Importantly, a triple-drug combination suppresses breast tumors by 94% and 87% at total dosages of 5 and 2.5 mg/kg, respectively, through synergy. Moreover, the cNPs retain their photothermal properties, which can be used to significantly inhibit multidrug resistance upon near-infrared laser irradiation. Overall, this work shows that our nanovehicle has great potential as a drug codelivery nanoplatform for effective combination therapy that is adaptable to other cancer types and to molecular targets associated with disease progression.

     
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  3. Abstract

    Nanoparticles with diverse structures and unique properties have attracted increasing attention for their widespread applications. Co‐precipitation under rapid mixing is an effective method to obtained biocompatible nanoparticles and diverse particle carriers are achieved by controlled phase separation via interfacial tensions. In this Minireview, we summarize the underlying mechanism of co‐precipitation and show that rapid mixing is important to ensure co‐precipitation. In the binary polymer system, the particles can form four different morphologies, including occluded particle, core‐shell capsule, dimer particle, and heteroaggregate, and we demonstrate that the final morphology could be controlled by surface tensions through surfactant, polymer composition, molecular weight, and temperature. The applications of occluded particles, core‐shell capsules and dimer particles prepared by co‐precipitation or microfluidics upon the regulation of interfacial tensions are discussed in detail, and show great potential in the areas of functional materials, colloidal surfactants, drug delivery, nanomedicine, bio‐imaging, displays, and cargo encapsulation.

     
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  4. Abstract

    Co‐precipitation is generally refers to the co‐precipitation of two solids and is widely used to prepare active‐loaded nanoparticles. Here, it is demonstrated that liquid and solid can precipitate simultaneously to produce hierarchical core–shell nanocapsules that encapsulate an oil core in a polymer shell. During the co‐precipitation process, the polymer preferentially deposits at the oil/water interface, wetting both the oil and water phases; the behavior is determined by the spreading coefficients and driven by the energy minimization. The technique is applicable to directly encapsulate various oil actives and avoid the use of toxic solvent or surfactant during the preparation process. The obtained core–shell nanocapsules harness the advantage of biocompatibility, precise control over the shell thickness, high loading capacity, high encapsulation efficiency, good dispersity in water, and improved stability against oxidation. The applications of the nanocapsules as delivery vehicles are demonstrated by the excellent performances of natural colorant and anti‐cancer drug‐loaded nanocapsules. The core–shell nanocapsules with a controlled hierarchical structure are, therefore, ideal carriers for practical applications in food, cosmetics, and drug delivery.

     
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