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Integrating multimodality bioimaging and multiple stimuli-responsive controlled drug release properties into one single nanosystem for therapeutic application is highly desirable but still remains a challenge. Herein, we coated a hollow mesoporous silica shell on to upconversion nanoparticles (UCNPs) and conjugated pillarene-based supramolecular valves on to surface of UCNPs@hm-SiO2 using amine-coumarin phototriggers to obtain the multifunctional nanoparticles, UCNPs@hm-SiO2-Cou-Cys-DOX/WP[5]. Benefiting from the core-shell structured UCNPs, the UCNPs@hm-SiO2-Cou-Cys-DOX/WP[5] can serve as efficient contrast agents for upconversion luminescence and T1-weighted magnetic resonance imaging in vitro/in vivo. More importantly, depending on exquisitely designed supramolecular valves, UCNPs@hm-SiO2-Cou-Cys-DOX/WP[5] can realize zero-premature release under normal physiological conditions (pH 7.4), which produces minimal damage to normal tissue, whereas this nanosystem can respond to several disease-related signals, including acid (most cancers), alkali (metabolic alkalosis), and Zn2+ (Alzheimer's disease), along with two external stimuli, including near-infrared (NIR) light and reductive electrical potential, via altering the spatial structure of pseudorotaxanes, disassembling the molecular stalks, or undergoing photochemical reactions, ultimately resulting in opening of the gatekeepers and release of encapsulated drugs. The multifunctional UCNP-based nanoparticles were endowed with such quintuple stimuli-responsive controlled release characteristics. Specifically, in anticancer application, the rational utilization of the two of them, acid and NIR light, could regulate the release amount and rate of DOX from UCNPs@hm-SiO2-Cou-Cys-DOX/WP[5], accelerate the accumulation of DOX in cell nuclei, and thereby promote the cancer cell apoptosis, indicating that the nanomaterials have promising application in cancer treatment. This study provides a novel design strategy for constructing multifunctional UCNP-based nanoparticles with multiple stimuli-responsive drug release features, which have great potential in diagnosis and therapy of relevant diseases as theranostic nanomedicines.

We constructed triple-stimuli-responsive nanocontainers (T-SRNs), consisting of mesoporous silica nanoparticles for accommodating cargoes and bistable [2]pseudorotaxanes for regulating cargoes and realizing controlled release. T-SRNs eliminate premature leakage of model cargoes under neutral solution conditions by the formation of complexes of water-soluble carboxylate-substituted pillar[5]arenes (WP5) with 1,6-hexanediammonium (HDA) recognition stations to block pore orifices. After exposure to acid, alkali pH or Zn2+ environments, T-SRNs release encapsulated cargoes promptly, which can be attributed to the dethreading of WP5 from HDA sites by different approaches and the lack of stoppers. The unique acid/alkali/Zn2+-responsive controlled release characteristic mean that T-SRNs have potential in some application fields. Herein, MTT assays and in vitro release of doxorubicin from T-SRNs demonstrate that T-SRNs can serve as promising targeted drug delivery vehicles.

In recent years, the unprecedented advances of biomedical nanotechnology have spurred the development of drug delivery systems (DDSs) based on multifarious nanomaterials in disease treatment and diagnostic purposes, which simultaneously boost the therapeutic outcome and circumvent the side effects. Among these, mesoporous silica nanoparticles (MSNs) are acknowledged as one of the most promising candidates for cargo delivery. Their remarkable intrinsic features, including size and porosity tunability, large surface area, high pore volume, versatile surface functionality as well as biocompatibility, have arouse tremendous research of MSNs as multifunctional delivery platforms. In particular, intelligent MSNs-based controlled delivery systems with stimuli-responsive characteristics hold great promise in personalized precision medicine in clinical applications. Notably, benefiting from the tunable pore size and diversified surface chemistry, MSNs-based systems can transport a variety of therapeutic agents such as small-molecule drug, gene, peptide, as well as protein, which have tremendous potential to treat diverse types of diseases, including carcinoma, bacterial infections (infectious diseases), diabetes, bone disorders, Alzheimer’s disease, etc. In this review, a brief overview of MSNs and their features, together with the discussions on engineering of stimuli-responsive MSNs-based systems for on-demand payload delivery is presented. Further, the application of the state-of-the-art MSNs-based delivery systems in multifarious disease therapeutics (not limited to carcinoma) with a particular focus on recent studies is summarized. Finally, the clinical translation issues encountered by these delivery platforms and their possible solutions together with future perspectives of MSN-based systems in clinics are also mentioned.

Motivated by the demand for anticorrosion coating with high performance to improve the reliability and sustainability of metallic materials in corrosive environments, smart nanocontainers that can confer active protection have been highly desirable. The combination of nanocontainer researches and anticorrosion technology bolsters the development of “smart” anticorrosion coatings. Due to the participation of nanocontainers, healing agents undergo stimulus-responsive release to fulfill repairing function. Integrating both passive barrier function and self-healing property, this burgeoning technology is more reliable in proving long-term protection. We summarize the working mechanism of these coatings based on different types of nanocontainer scaffold and the triggers. The characterization methods of nanocontainer-based anticorrosion coatings are also discussed.

We demonstrate for the first time how to assemble mechanized hollow zirconia nanospheres (MHzNs), consisting of hollow mesoporous zirconia nanospheres (HMZNs) as nanoscaffolds and supramolecular switches anchored on the exterior surface of HMZNs. The remarkable advantage of substitution of HMZNs for conventional mesoporous silica nanoscaffolds is that HMZNs can suffer the hot alkaline reaction environment, which provides a novel strategy for functionalization and thus achieve dual pH-mediated controlled release functions by simple and practicable assembly procedure. Under neutral solution, cucurbituril[7] (CB[7]) macrocycles complexed with propanone bis(2-aminoethyl)ketal (PBAEK) to form [2]pseudorotaxanes as supramolecular switches, blocking the pore orifices and preventing the undesirable leakage of cargoes. When solution pH was adjusted to alkaline range, CB[7] macrocycles, acting as caps, disassociated from PBAEK stalks and opened the switches due to the dramatic decrease of ion-dipole interactions. While under acidic conditions, PBAEK stalks were broken on account of the cleavage of ketal groups, resulting in the collapse of supramolecular switches and subsequent release of encapsulated cargoes. MHzNs owning dual pH-mediated controlled release characteristic are expected to apply in many fields. In this work, the feasibility of doxorubicin (DOX)-loaded MHzNs as targeted drug delivery systems was evaluated. In vitro cellular studies demonstrate that DOX-loaded MHzNs can be easily taken up by SMMC-7721 cells, can rapidly release DOX intracellularly, and can enhance cytotoxicity against tumor cells, proving their potential for chemotherapy.

Advanced rechargeable lithium-based batteries have a profound effect on our global society and polymer materials are one of the key components of these batteries. The key roles of polymers applied in battery technology are presented in terms of binders, package coatings, separators, and electrolytes. However, the loathsomely structural changes during repeated charge/discharge processes result in the mechanical fracture problems of polymers inside batteries, which significantly reduce the cycling lifetimes. The use of intrinsic self-healing polymers as substitutes is one of the most favored strategies for reviving lithium-based batteries since self-healing polymers spontaneously eliminate the mechanical cracks or damages and result in greatly enhanced electrochemical performances. In this review, we first introduce the advances and working mechanism of intrinsic self-healing polymers. Then, we discuss the opportunities and challenges in the development of advanced lithium-based batteries with Si, Li-metal, S electrodes, and polymer electrolytes, respectively, and summarize the up-to-date key progress in intrinsic self-healing polymers for solving the above-mentioned challenges. Finally, we propose some designing principles of desired intrinsic self-healing polymers from the perspectives of basic structures, ionic conductivities, mechanical properties, chemical interactions, and the self-healing capabilities.

Novel quadruple stimuli-responsive mechanized silica nanoparticles were constructed by installation of supramolecular nanovalves onto the exterior surface of mesoporous silica nanoparticles. The release of cargo molecules is triggered by acid/Zn2+ /alkali/reduction potential stimuli. This has potential application in the development of drug delivery systems or construction of smart anticorrosion coatings.

Cucurbit[6]uril-based reversible bistable [2]pseudorotaxanes were designed, synthesized and installed on the surface of mesoporous silica nanoparticles as supramolecular nanovalves. The assembled mechanized silica nanoparticles realize the multistage pH-controlled release of benzotriazole and the potential for reutilization.

Luminescent graphene quantum dots (GQDs) have been capped onto the nanopores of mesoporous silica nanoparticles (MSNs) through an acid-cleavable acetal bond. Herein, the GQDs behave as dual-purpose entities that act as capping agents and also exhibit excellent photoluminescence property.