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Alzheimer's disease (AD) is a common neurodegenerative disease that brings about enormous economic pressure to families and society. Inhibiting abnormal aggregation of Aβ and accelerating the dissociation of aggregates is treated as an effective method to prevent and treat AD. Recently, nanomaterials have been applied in AD treatment due to their excellent physicochemical properties and drug activity. As a drug delivery platform or inhibitor, various excellent nanomaterials have exhibited potential in inhibiting Aβ fibrillation, disaggregating, and clearing mature amyloid plaques by enhancing the performance of drugs. This review comprehensively summarizes the advantages and disadvantages of nanomaterials in modulating amyloid aggregation and AD treatment. The design of various functional nanomaterials is discussed, and the strategies for improved properties toward AD treatment are analyzed. Finally, the challenges faced by nanomaterials with different dimensions in AD-related amyloid aggregate modulation are expounded, and the prospects of nanomaterials are proposed.

A rational design of chiroptical active materials from a multi-component co-assembly remains a great challenge due to the spontaneous pathway competition and complexity. In this study, we report a modularized, ternary component co-assembly system constituted by two N-terminated aromatic glutamic amino acids and an imidazole-based binder, which demonstrate mutual binding behaviors via aromatic interactions and complementary H-bonds that allow for flexible manipulation of the chiroptical activities, including circularly polarized light absorbance and luminescence. Through a modular combination, we synthesized up to six self-assembled aggregates with distinct chiroptical activities, showing chirality emergence, transfer, amplification and inversion behaviors. The modular molecular self-assembly protocol provides an alternative route to the noncovalent synthesis of chiroptical active materials with high throughput efficacy.

Efficient access to evodiamine and its analogues is presented via Lewis acid catalysis. In this reaction, three chemical bonds and two heterocyclic-fused rings are constructed in one step. The reaction shows good functional group tolerance and atom economy, and various heteroatom-containing evodiamine analogues are obtained in moderate to excellent yields even on a gram scale. An anti-tumor study in vitro demonstrates compound 2b possesses potent efficacy against hepatoma cell line (IC50 = 5.7 μM).

Here, we present an unprecedented pathway to α-sulfenylated carbonyl compounds from commercially available thiols and universally employed TEMPO and its analogues, which act as C3 synthons through skeletal rearrangement under simple and metal-free conditions. Mechanism studies suggest that this reaction involves a consecutive radical oxidation and cation coupling process. TEMPO analogues and thiols serve as oxidants and reductive reagents, respectively, along the radical process, while in the coupling process, the former ones afford C3 synthons to couple with related sulfur sources.

A novel tert-butyl hydroperoxide (TBHP) promoted CH2-extrusion reaction of α-amino carbonyl compounds has been developed, which is driven by a demethylenation process to give various ring contraction products γ-lactams under radical conditions. The reaction shows good functional group tolerance and excellent chemo/regioselectivity; all the desired products are obtained in moderate to excellent yields.

Retraction of ‘MiR-320d suppresses the progression of breast cancer via lncRNA HNF1A-AS1 regulation and SOX4 inhibition’ by Shuai Shi et al., RSC Adv., 2018, 8, 19196–19207, https://doi.org/10.1039/C8RA01200H.

Total synthesis of the originally proposed chrysamide B (2) is described, which features a convergent assembly of the chiral piperazine core and epoxy-acid. Mismatched spectroscopic data for the synthetic sample compared to that for the isolate led us to propose the revised structure 3 based on biosynthetic considerations. In a further antibacterial assay, chrysamide B and its diastereomer 2 exhibited different activities.

The surface functionalities of nanomaterials provide an invaluable resource to biomaterials science in the form of biomolecular recognition, sensing, self-assembly and drug delivery. This paper presents a one-step procedure for the facile preparation of highly cross-linked raspberry-like nano/microspheres by the dispersion polymerization of polyethylene glycol dimethacrylate and N-vinylimidazole. Ionic liquid-functionalized reactions were then conducted on the surface of the raspberry-like nano/microspheres to investigate the effects of the functional groups on the peptide adsorption in aqueous media. Various characterization methods were employed to characterize the as-prepared nano/microspheres and to track the experiment process. The results reveal that the nano/microspheres were raspberry-like, monodisperse and stable. It was also found that the adsorption of immunostimulating hexapeptide from human (IHH) was correlated with the surface properties of the ionic liquid-functionalized nano/microspheres, which demonstrated their potential use for the immobilization and release of IHH in practical application.

Surface-imprinted microspheres were controllably synthesized using ionic liquid-functionalized microspheres with a highly cross-linked raspberry-like structure as the matrix via surface molecular self-assembly and precipitation polymerization in aqueous media at room temperature. An immunostimulating hexapeptide from human (IHH) with medical properties was chosen as a template molecule in the preparation of different molecularly imprinted microspheres (MIMs). The experiment process was tracked and the as-prepared microspheres were well characterized. Results reveal that the adsorption capacity and selective recognition of MIMs have a direct relationship with the properties of the functional chain of the ionic liquid-functionalized microspheres. Moreover, MIMs that have both high adsorption capacity and good selective recognition were used in competitive rebinding tests and analysis of urine samples, which demonstrated their potential use for IHH enrichment and in real samples.

An approach for synthesizing core–shell imprinting polymers using P(EGDMA-CMS) microspheres prepared via dispersion polymerization as a core and employing a surface imprinting technique and iniferter-induced radical polymerization is described. N,N-Diethyldithiocarbamyl groups were immobilized on the surface of the supporting microspheres to form the surface iniferter and further prepare the imprinting layer. Thymopentin (TP5) was selected as the template molecule, which was known to be an immunomodulating agent that had medical properties. Here, a bifunctional ionic liquid (IL), namely, 1-vinyl-3-carbamoylmethyl-imidazolium chloride ([VACMIM]Cl), was synthesized and employed as a novel functional monomer on the basis of the demands of peptide imprinting and the designability of ILs. Under irradiation by UV light, the surface iniferter decomposed and then polymerization was initiated to form a thin surface imprinting layer with specific recognition cavities for TP5. The surface imprinting layer possessed a uniform thickness of ∼35 nm, which was beneficial for the mass transfer of the template TP5, owing to good control of the thickness of the imprinting layer by controlled/living radical polymerization (CRP). The polymeric microspheres were fully characterized and their adsorption properties were investigated. The surface molecular imprinting microspheres (SMIMs) displayed high binding affinity, good selective specificity, rapid adsorption equilibrium and satisfactory reusability. The Scatchard plots of the SMIMs could be fitted to one straight line, which suggested that there was only one kind of binding site. Furthermore, the method of combining a surface imprinting technique and CRP together can be extended to a wide range of applications for chemical sensors, drug delivery and the separation of biomacromolecules.

In this study, an assumption that a micromolecular monomer could easily permeate into the inside of a protein and alter its conformation, while an inflexible macromolecular monomer may interact with the surface of the protein and thus maintain the integrity of the template protein's structure was proposed for the first time and confirmed by using circular dichroism and synchronous fluorescence spectroscopy. The protein imprinted hydrogels composed of macromolecular monomers or their equivalent micromolecular monomers were characterized and carried out in the competitive adsorption and adsorption isotherm experiments. The adsorption isotherm behaviours described by the Langmuir model revealed that a higher binding affinity was observed between the template protein and imprinted hydrogels made by a macromolecular monomer. The competitive adsorption results also demonstrated the imprinted hydrogels prepared by the macromolecular monomer exhibited much better specific recognition ability to the template protein. Therefore, the strategy of using a macromolecule to imprint could effectively overcome the mutability of protein during the preparation of imprinted polymers, and consequently would promote the development of imprinting technology.

Ionic liquid based molecularly imprinted polymers have attracted considerable attention as biomimetic recognition materials due to their water-compatibility and high binding capacities. However, the selective recognition was unsatisfactory. In order to overcome this defect, we developed a novel dummy template ionic liquid based molecularly imprinted polymer, which used 1-butyl-3-vinylimidazolium α-aminohydrocinnamic acid salt as a functional monomer and the dummy template. Binding experiments showed that the obtained molecularly imprinted polymer possesses a high binding capacity (280.18 μmol g−1), imprinting factor (3.17) and selectivity factor (5.75). Molecular simulation results demonstrated that the high selectivity is attributed to the formation of ion-pairs between imidazolium and L-phenylalanine, which could be located in the imprinted cavities to improve the imprinted material’s efficiency. Subsequently, the dummy template ionic liquid based imprinted polymer was employed as packing in a solid phase extraction cartridge to analyze the L-phenylalanine in the blood of a phenylketonuria patient. The results indicated that the obtained dummy template ionic liquid based imprinted polymer has good analytical performance. Thus, the dummy imprinting combined with the ionic liquid is a useful way to improve the specific recognition of ionic liquid based molecular imprinted polymers, so that this method offers promising new applications in the field of the analysis of biological samples.

Novel water-compatible ionic liquid-functionalized microspheres with molecularly imprinted shell layer were controllably synthesized via precipitation polymerization and surface imprinting technique. Here, a room-temperature ionic liquid was synthesized to prepare these surface-imprinted microspheres with excellent water solubility and multiple binding sites with template molecules. The peptide drug thymopentin (TP5) was chosen as a template molecule, which is known as an immunomodulating agent. The as-prepared microspheres were fully characterized. Results reveal that ionic liquid incorporation significantly improves the adsorption of TP5. Moreover, the adsorption property and recognition capability towards TP5 are closely related to the synergetic effect of electrostatic interaction and hydrogen bonding. Through employing the synergetic effect of directional and non-directional interactions, the surface-imprinted microspheres exhibit high adsorption capacity, good selective recognition, and rapid binding ability for TP5. The surface-imprinted microspheres demonstrate potential usage for TP5 enrichment from other biomolecules, and the proposed method was successfully applied for TP5 determination in thymopentin injection and urine.