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Aims The cellular functions of bladder urothelial cells in interstitial cystitis/bladder pain syndrome (IC/BPS) have not been well revealed and understood. Thus, the study aims to identify key genes and significant pathways in urothelium corresponding to IC/BPS in a lipopolysaccharide (LPS)-induced cystitis model and provide novel clues related to diagnosis and treatment of IC/BPS. Methods Human urothelial cells (HUCs) were incubated with LPS (50 μg/ml for 24 h). Microarray was applied to analyze the differentially expressed genes (DEGs) between HUCs under LPS treatment and the control group. DEGs in the two groups were identified and then used for enrichment analysis. Subsequently, protein-protein interaction (PPI) network based on DEGs was constructed. Lastly, the top five key genes were identified through the Cytoscape (version 3.7.2) using the "Clustering Coefficient" algorithm. Results One hundred and seventy-one DEGs (96 upregulated genes and 75 downregulated genes) were identified between the LPS treatment and control group. The established PPI network was composed of 169 nodes and 678 edges. Moreover, C19orf33, TRIM31, MUC21, ELF3, and IFI27 were identified as hub genes in the PPI network. Subsequently, a statistically increased expression level of TRIM31 and ELF3 was validated by real-time quantitative-polymerase chain reaction and immunohistochemistry in bladder tissues from 20 patients with IC/BPS. Conclusions TRIM31 and ELF3 may be the two hub genes in urothelium corresponding to IC/BPS. More studies are warranted to further validate the findings. The identified marker genes may be useful targets for further studies to develop diagnostic tools and more effective therapies for a broader group of women with IC/PBS.

A series of azo-containing copolymeric assemblies based on poly(N,N-dimethylaminoethyl methacrylate)-b-poly[(benzyl methacrylate)-co-(4-phenylazophenyl methacrylate)] [PDMA-b-P(BzMA-co-AzoMA)] were prepared by reversible addition–fragmentation chain transfer polymerization-induced self-assembly at high solid contents. Depending on the chain length of P(BzMA-co-AzoMA), spheres, worms, and vesicles were readily prepared. These azo-containing wormlike micelles underwent reversible worm-to-vesicle transformation upon alternative UV/vis light irradiation. By investigating the morphology evolution, a series of intermediates were observed, including coalesced worms as well as “octopus”-like and “jellyfish”-like structures. The morphology transformation was rationalized by the volume change of the P(BzMA-co-AzoMA) block caused by the trans–cis isomerization of the azobenzene groups. It is the first demonstration of light-stimulated reversible worm-to-vesicle transition and would benefit for the understanding of m...

Chemically incorporating Schiff base interactions into silicate frameworks endows the obtained mesoporous organosilica based drug carriers with ultrafast pH-responsive degradability and efficient anti-cancer drug release kinetics, resulting in enhanced cancer therapy.

A one-step synthesis of nanotubes by RAFT dispersion polymerization of cyclodextrin/styrene (CD/St) complexes directly in water is presented. The resulted amphiphilic PEG-b-PS diblock copolymers self-assemble in situ into nanoparticles with various morphologies. Spheres, worms, lamellae, and nanotubes were controllably obtained. Because of the complexation, the swelling degree of polystyrene (PS) blocks by free St is limited, resulting in limited mobility of PS chains. Consequently, kinetically trapped lamellae and nanotubes were obtained instead of spherical vesicles. During the formation of nanotubes, small vesicles first formed at the ends of the tape-like lamellae, then grew and fused into nanotubes with a limited chain rearrangement. The introduction of a host-guest interaction based on CDs enables the aqueous dispersion polymerization of water-immiscible monomers, and produces kinetically trapped nanostructures, which could be a powerful technique for nanomaterials synthesis.

Stimuli responsive polymers have been extensively studied as nanocarriers for drug delivery systems (DDSs), especially those based on supramolecular interactions. Cyclodextrin (CD) is one kind of widely applied host molecule, and the host-guest interactions between CD and different counterparts can respond to different stimuli and thus can be applied as responsive linkers for polymeric DDSs. In this review, the polymeric nanocarriers based on the host-guest interactions between CD and ferrocene, azobenzene, and benzimidazole as DDSs are summarized, with redox, light, and pH sensitivity, respectively. The mechanisms for the stimuli responsive ability of the linkers, the application of them for construction of DDSs with different polymer structures, and the controlled release behaviors have been focused. In addition, the outlook and challenge of these systems are discussed.

A series of polymeric dispersants in three different structural types, namely AB diblock, ABA triblock and comb, were synthesised via reversible addition–fragmentation chain transfer (RAFT) polymerisation. They were systematically designed and optimised with varying molecular weights, compositions, anchoring and stabilising chain lengths, then investigated and compared over the dispersion performance of SiO2 particles in organic media. The comparisons indicated that the optimised AB diblock poly(2-(dimethylamino)ethyl methacrylate)30-b-poly(ethyl methacrylate)40 (PD30-b-PE40) and ABA triblock (PD30-b-PE60-b-PD30) dispersants enabled homogeneous SiO2 particle dispersion, which were more effective in reducing particle size and system viscosity than the comb dispersant poly((2-(dimethylamino)ethyl methacrylate)30-co-(poly(propylene glycol) acrylate)15) (P(D30-co-PPGA15)). In particular, it was found that AB diblock copolymer dispersants are generally at least as effective as or better than their ABA triblock equivalents in particle dispersion and stabilisation. Thus, the dispersion effectiveness of the three structural types can be ordered as: AB ≥ ABA > comb. Furthermore, structure–performance relationships were developed between dispersants' molecular structures and dispersion performances, in order to provide constructive guidance for the structural design and selection of polymeric dispersants for effective particle dispersion and stabilisation in organic media for various applications.

Potential-stimulated Pickering emulsions, using electrochemical responsive microgels as particle stabilizers, are prepared and used for biocatalysis. The microgels are constructed from cyclodextrin functionalized 8-arm poly(ethylene glycol) (8A PEG-CD) and ferrocene modified counterparts (8A PEG-Fc) via CD/Fc host-guest chemistry. Taking advantage of the redox reaction of Fc, the formation and deformation of the microgels and corresponding Pickering emulsions can be reversibly stimulated by external potential, and have been used for the hydrolysis of triacetin and kinetic resolution reaction of (R,S)-1-phenylethanol catalyzed by lipases. Potential stimulated destabilization of the emulsion realizes an effective separation of the products and enzyme recycling.

Electrochemical stimulus is a clean and simple choice of stimulating source in the field of stimuli-responsive materials. Herein, we report an electrochemically-responsive hybrid assembly of magnetic nanoparticles (Fe3O4@SiO2-PGMA-CD) and polyethylene glycol-Fc (PEG-Fc) based on the host–guest interaction between β-cyclodextrin and ferrocene groups. Through electrochemical control, the hydrophilic polymer chains can be reversibly linked to or dropped off from the surface of the magnetic nanoparticles. Thus, the hydrophobic property of the surface together with the protein adsorption ability of the magnetic nanoparticles can be conveniently adjusted by voltages applied. A reversible protein adsorption/release transition from this novel hybrid material has been realized, demonstrated by the bovine serum albumin adsorption experiment. Therefore, an elegant material is introduced to achieve electrochemically-controlled reversible magnetic separation of proteins.

Biological cyclization is highly efficient, and this can be attributed to the conformation of the backbone of the biopolymer. Taking advantage of metal-coordination geometry, we developed a method for conformation-directed polymerization cyclization through rational design of metal carbonyl monomers that could be used to produce cyclic macromolecules, even in bulk. P FpR [P Fp=(PPh2 (CH2 )3 Cp)Fe(CO)2 with the phosphine group tethered on the cyclopentadiene (Cp) ring; R=CH3 or (CH2 )5 CH3 ] was designed and synthesized for migration insertion polymerization to generate P(P FpR) with the polymer backbone containing Cp-Fe bonds. Growth of the backbone led to a cyclic conformation with close end-to-end distances, which facilitated the cyclization. This conformation-directed cyclization was attributed to the piano-stool metal-coordination geometry of the repeating units and the low rotational barrier of the Cp-Fe bonds in the backbone. The produced macrocycles, which contain a metal carbonyl coordination structure in their backbones, are rigid, unlike many organic macrocycles. The macrocycles thus have a large excluded volume. This new type of metal carbonyl macrocycle will be of interest as a building block for supramolecular chemistry and in the exploration of novel materials.

A supramolecular hydrogel was prepared through the host–guest interaction between β-cyclodextrin (β-CD) and ferrocene (Fc) with two polymers as pendant groups. Reversible gel–sol transition was observed with the alternative stimuli of a positive potential (or an oxidant) and a negative potential (or a reductant). The hydrogel not only had good self-healing ability due to the dynamic host–guest interaction, but also was prepared under mild conditions and could respond to moderate electrochemical stimuli. Good biocompatibility endowed the hydrogel with potential practical and real-life applications, especially in tissue engineering and drug release field.

Electrochemical stimuli have attracted much attention in recent years as they are simple, clean and can be widely applied in biological systems and material science. As one type of common guest molecules, ferrocene and its derivatives have been well studied with different host molecules, mainly including cyclodextrins, cucurbiturils, pillararenes and calixarenes. This article generally summarizes the recent work on the host-guest interactions between ferrocene derivatives and their host molecules, as well as various supramolecular systems based on these interactions. In addition, the development and outlook of electrochemical responsive systems are also discussed.

Voltage stimulus is considered as a clean and simple method in the field of stimuli-responsive polymer systems, in which the system based on β-cyclodextrin (β-CD) and ferrocene (Fc) has attracted considerable attention. Herein, we report voltage-responsive micelles based on the assembly of two biocompatible homopolymers, namely, the poly(ethylene glycol) homopolymer modified with β-CD (PEG–β-CD) and the poly(L-lactide) homopolymer modified with Fc (PLLA–Fc). Through host–guest interactions between β-CD and Fc, the two homopolymers connect together, forming a non-covalent supramolecular block copolymer PLLA–Fc/PEG–β-CD. PLLA–Fc/PEG–β-CD can further self-assemble to form stable micelles in aqueous solution. Through electrochemical control, a reversible assembly–disassembly transition of this micellar system was realized. Voltage-controlled drug release based on this system was also conducted successfully.

Summary Different from the chemical structure and self-assembly behavior of traditional block copolymer, a homopolymer self-assembly approach with reversible linkage based on linker chemistry has been developed. The strategy could be used for the preparation of stimuli-responsive polymer networks with reversible linkers. A redox-responsive supramolecular hydrogel was obtained by two hydrophilic copolymers (poly(N, N'-dimethylacrylamide-r-glycidyl methacrylateglycidyl methacrylate) and poly(N, N'-dimethylacrylamide-r-hydroxyethyl methacrylateglycidyl methacrylate)) with β-CD and ferrocene pendent groups, respectively. The hydrogel exhibited gel-sol transition after the addition of an oxidizing agent FeCl3 and returned to its gel state when a reducing agent ascorbic acid was added. SEM observation showed that the hydrogel had a porous network structure. The host-guest interaction between β-CD and ferrocene was a dominant driving force for the formation of the hydrogel.

We present a new, efficient approach to achieve superior dispersibility of single-walled carbon nanotubes (SWNTs) in water by integrating reversible host–guest interaction and π–π stacking. In this approach, β-cyclodextrin (β-CD) was first modified with a pyrene group to be adsorbed onto the wall of pristine SWNTs via π–π stacking, followed by further functionalization with ferrocene (Fc)-terminated water-soluble poly(ethylene glycol) (PEG) through supramolecular host–guest interaction between β-CD and Fc. Upon alternate electrochemical oxidative/reductive stimuli, the reversible host–guest pair enabled the PEG-Fc@Py-CD@SWNTs to exhibit switchable conversion between dispersion and aggregation states. Electric field controllable PEG-Fc@Py-CD@SWNTs with good reversibility and intact nanotube structure may find potential applications in selective screening of SWNTs, biosensors, and targeted drug delivery.

A photoresponsive microgel is designed by the combination of a noncovalent assembly strategy with a covalent cross-linking method. End-functionalized poly(ethylene glycol) with azobenzene [(PEG-(Azo)(2))] was mixed with acrylate-modified β-CD (β-CD-MAA) to form photoresponsive inclusion complex through host-guest interaction. The above photoresponsive complex was cross-linked by thiol-functionalized PEG (PEG-dithiol) via Michael addition click reaction. The photoreversibility of resulted microgel was studied by TEM, UV-Vis spectroscopy, and (1)H NMR measurements. The characterization results indicated that the reversible size changes of the microgel could be achieved by alternative UV-Vis irradiations with good repeatability.

Electrochemical stimuli have attracted much attention in recent years as they are simple, clean and can be widely applied in biological systems and material science. As one type of common guest molecules, ferrocene and its derivatives have been well studied with different host molecules, mainly including cyclodextrins, cucurbiturils, pillararenes and calixarenes. This article generally summarizes the recent work on the host–guest interactions between ferrocene derivatives and their host molecules, as well as various supramolecular systems based on these interactions. In addition, the development and outlook of electrochemical responsive systems are also discussed.

To face the increasing demand of self-healing hydrogels with biocompatibility and high performances, a new class of cellulose-based self-healing hydrogels are constructed through dynamic covalent acylhydrazone linkages. The carboxyethyl cellulose-graft-dithiodipropionate dihydrazide and dibenzaldehyde-terminated poly(ethylene glycol) are synthesized, and then the hydrogels are formed from their mixed solutions under 4-amino-DL-phenylalanine (4a-Phe) catalysis. The chemical structure, as well as microscopic morphologies, gelation times, mechanical and self-healing performances of the hydrogels are investigated with 1H NMR, Fourier transform infrared spectroscopy, atomic force microscopy, rheological and compression measurements. Their gelation times can be controlled by varying the total polymer concentration or 4a-Phe content. The resulted hydrogels exhibit excellent self-healing ability with a high healing efficiency (≈96%) and good mechanical properties. Moreover, the hydrogels display pH/redox dual responsive sol-gel transition behaviors, and are applied successfully to the controlled release of doxorubicin. Importantly, benefitting from the excellent biocompatibility and the reversibly cross-linked networks, the hydrogels can function as suitable 3D culture scaffolds for L929 cells, leading to the encapsulated cells maintaining a high viability and proliferative capacity. Therefore, the cellulose-based self-healing hydrogels show potential applications in drug delivery and 3D cell culture for tissue engineering.