Due to their unique structures and properties, three-dimensional hydrogels and nanostructured particles have been widely studied and shown a very high potential for medical, therapeutic and diagnostic applications. However, hydrogels and nanoparticulate systems have respective disadvantages that limit their widespread applications. Recently, the incorporation of nanostructured fillers into hydrogels has been developed as an innovative means for the creation of novel materials with diverse functionality in order to meet new challenges. In this review, the fundamentals of hydrogels and nanoparticles (NPs) were briefly discussed, and then we comprehensively summarized recent advances in the design, synthesis, functionalization and application of nanocomposite hydrogels with enhanced mechanical, biological and physicochemical properties. Moreover, the current challenges and future opportunities for the use of these promising materials in the biomedical sector, especially the nanocomposite hydrogels produced from hydrogels and polymeric NPs, are discussed.
Multifunctional and multiresponsive hydrogels have presented a promising platform to design and fabricate smart devices for application in a wide variety of fields. However, their preparations often involve multistep preparation of multiresponsive polymer precursors, tedious reactions to introduce functional groups or sophisticated molecular designs. In this work, a multifunctional boronic acid-based cross-linker bis(phenylboronic acid carbamoyl) cystamine (BPBAC) was readily prepared from inexpensive commercially available 3-carboxylphenylboronic acid (CPBA) and cystamine dihydrochloride, which has the ability to cross-link the cis-diols and catechol-containing hydrophilic polymers to form hydrogels. Due to the presence of the reversible and dynamic boronate ester and disulfide bonds, the obtained hydrogels were demonstrated to not only possess pH, glucose, and redox triresponsive features, but also have autonomic self-healing properties under ambient conditions. Moreover, we can modulate the rheological and mechanical properties by simply adjusting the BPBAC amount. The features, such as commercially available starting materials, easy-to-implement approach, and versatility in controlling cross-linking network and mechanical properties, make the strategy described here a promising platform for fabricating multifunctional and smart hydrogels.
A turn-on orange-red fluorescent nanosensor based on rhodamine B derivative-functionalized graphene quantum dots (RBD-GQDs) has been successfully synthesized for Fe(3+) detection with high sensitivity and selectivity. By connecting with GQDs, the water solubility, sensitivity, photostability, and biocompatibility of RBD are drastically improved. The most distinctive feature of the RBD-GQDs, which sets them apart from other previously reported fluorophores or GQDs, is that they with the detection limits as low as 0.02 μM are demonstrated as a Fe(3+) turn-on fluorescent nanosensor in cancer stem cells. Fe(3+) binding to such GQDs (RBD-GQDs-Fe(3+)) with orange-red fluorescence of 43% quantum yield were demonstrated to be the biomarkers for cancer stem cell imaging.
Large
doses of anticancer drugs entering cancer cell nuclei are
found to be effective at killing cancer cells and increasing chemotherapeutic
effectiveness. Here we report red-emissive carbon quantum dots, which
can enter into the nuclei of not only cancer cells but also cancer
stem cells. After doxorubicin was loaded at the concentration of 30
μg/mL on the surfaces
of carbon quantum dots, the average cell viability of HeLa cells was
decreased to only 21%, while it was decreased to 50% for free doxorubicin.
The doxorubicin-loaded carbon quantum dots also exhibited a good therapeutic
effect by eliminating cancer stem cells. This work provides a potential
strategy for developing carbon quantum-dot-based anticancer drug carriers
for effective eradication of cancers.
Organic
contaminants in water have become one of the most serious
environmental problems worldwide. Adsorption is one of the most promising
approaches to remove organic pollutants from water. However, the existing
adsorbents have relatively low removal efficiency, complex preparation
processes, and high cost, which limit their practical applications.
Here, we developed three-dimensional (3D) zirconium metal–organic
frameworks (MOFs) encapsulated in a natural wood membrane (UiO-66/wood
membrane) for highly efficient organic pollutant removal from water.
UiO-66 MOFs were in situ grown in the 3D low-tortuosity wood lumens
by a facile solvothermal strategy. The resulting UiO-66/wood membrane
contains the highly mesoporous UiO-66 MOF structure as well as many
elongated and open lumens along the direction of the wood growth.
Such a unique structural feature improves the mass transfer of organic
pollutants and increases the contact probability of organic contaminants
with UiO-66 MOFs as the water flows through the membrane, thereby
improving the removal efficiency. Furthermore, the integrated multilayer
filter consisting of three pieces of UiO-66/wood membranes exhibits
a high removal efficiency (96.0%) for organic pollutants such as rhodamine
6G, propranolol, and bisphenol A at the flux of 1.0 × 103 L·m–2·h–1.
The adsorbed capacity of UiO-66/wood for Rh6G (based on the content
of UiO-66 MOFs) is calculated to be 690 mg·g–1. We believe that such low-cost and scalable production of the UiO-66/wood
membrane has broad applications for wastewater treatment and other
related pollutant removal.
The design and synthesis of high-performance n-type organic semiconductors are important for the development of future organic optoelectronics. Facile synthetic routes to reach the K-region of pyrene and produce 4,5,9,10-pyrene diimide (PyDI) derivatives are reported. The PyDI derivatives exhibited efficient electron transport properties, with the highest electron mobility of up to 3.08 cm V s . The tert-butyl-substituted compounds (t-PyDI) also showed good one- and two-photon excited fluorescence properties. The PyDI derivatives are a new family of aromatic diimides that may exhibit both high electron mobility and good light-emitting properties, thus making them excellent candidates for future optoelectronics.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.