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Since it is now possible to make, in a controlled fashion, an almost unlimited variety of nanostructure shapes, it is of increasing interest to understand the forms of biological control that nanoscale shape allows. However, a priori rational investigation of such a vast universe of shapes appears to present intractable fundamental and practical challenges. This has limited the useful systematic investigation of their biological interactions and the development of innovative nanoscale shape-dependent therapies. Here, we introduce a concept of biologically relevant inductive nanoscale shape discovery and evaluation that is ideally suited to, and will ultimately become, a vehicle for machine learning discovery. Combining the reproducibility and tunability of microfluidic flow nanochemistry syntheses, quantitative computational shape analysis, and iterative feedback from biological responses in vitro and in vivo, we show that these challenges can be mastered, allowing shape biology to be explored within accepted scientific and biomedical research paradigms. Early applications identify significant forms of shape-induced biological and adjuvant-like immunological control.

Tunable solid-state fluorescence of a cationic dye acridine orange (AO) aggregates were triggered by introducing an anionic biosurfactant sodium deoxycholate (NaDC) as matrix. The NaDC/AO assembles with morphology of flabellate and dumbbell-shaped fiber bundles were formed via ionic self-assembly (ISA) strategy and both the ratio of NaDC to AO and temperature have influence on the morphology. Composition and driving force analysis of the microfibers have been investigated. The results revealed that the interaction between NaDC and AO was strongly influenced by direct electrostatic forces between the COO groups in NaDC and N+ in AO, respectively. Besides the electrostatic interactions, which proved to be the main driving forces for the formation of the supramolecular aggregates, the π-π stacking and hydrogen bond interactions also makes some contribution. What’s more, the fluorescence have dramatically enhanced upon the formation of complex, and the wavelength and intensity of this solid-state aggregates fluorescence can be further controlled by the molar ratio of NaDC to AO which induced the fluorescence lifetime and fluorescence quantum yield both increase with the increased concentration of NaDC. Thus, it is expected that the facile design of tunable solid-state fluorescence material by the ISA strategy could be used to provide new insight for the development of solid luminescent materials.

Herein, a convenient on-off fluorescent probe was developed to detect iron ion (Fe 3+ ) with sensitivity and selectivity by using highly luminescent ionic liquid-functionalized carbon quantum dots (CQDs) which was prepared by one-step hydrothermal treatment using citric acid and 1-Aminopropyl-3-methylimidazolium. The sensitivity of CQDs for Fe 3+ was examined by measuring the fluorescence (FL) intensity of various concentrations of Fe 3+ in CQDs solution and the selectivity of CQDs for Fe 3+ was examined by adding different metal ions (Na + , Mg 2+ , Al 3+ , K + , Ca 2+ , Mn 2+ , Zn 2+ , Ag + , Cd 2+ , Pb 2+ and Ba 2+ ) into CQDs solution, respectively. The results indicated that the FL intensity of CQDs showed a good linear response to the concentrations of Fe 3+ in the range of 0–300 μmol L −1 (R 2 = 0.99) with a detection limit of 13.68 μmol L −1 . Furthermore, based on the redox mechanism, after the fluorescent of CQDs was quenched by Fe 3+ , different neurotransmitters and amino acids were added and the FL test show that only ascorbic acid (AA) can recover the intensity of the CQDs/Fe 3+ , indicating that CQDs/Fe 3+ can be further used as a on-off fluorescent probe for the detection of AA. It is expected that our strategy may offer a new approach for developing rapid, low cost and sensitive CQDs-based sensors for environmetal and biological sensing applications.

Prototypes of biosystems provide good blueprints for the design and creation of biomimetic systems. However, mimicking both the sophisticated natural structures and their complex biological functions still remains a great challenge. Herein, chloroplast mimics have been fabricated by one-step bioinspired amino acid mineralization and simultaneous integration of catalytically active units. Hierarchically structured crystals were obtained by the metal-ion-directed self-assembly of cystine (the oxidized dimer of the amino acid cysteine), with a porous structure and stacks of nanorods, which show similar architectural principles to chloroplasts. Porphyrins and enzymes can both be encapsulated inside the crystal during mineralization, rendering the crystal photocatalytically and enzymatically active for an efficient and sustainable synthesis of hydrogen and acetaldehyde in a coupled photoenzymatic reaction.

In this article, a sensitive and selective on–off–on fluorescence chemosensor, Tyloxapol (one kind of water soluble oligomer), was developed for the label-free detection of MnO4− ions in aqueous solution. From fluorescence experiments, it is demonstrated that Tyloxapol is a sensitive and selective fluorescence sensor for the detection of MnO4− directly in water over a wide range of anions including Cl−, Br−, I−, NO3−, H2PO4−, HCO3−, OH−, ClO4−, Ac−, SO42−, HPO42−, CO32−, C2O42−, S2−, SO32−, and Cr2O72−. Moreover, the fluorescence intensity of Tyloxapol has shown a linear response to MnO4− in the concentration range of 0 to 120 μmol L−1 with a detection limit of 0.392 μmol L−1 MnO4−. The interaction mechanism demonstrated that our on–off fluorescent oligomer probe for detecting Mn(VII) is based on the inner filter effect (IFE) because the absorption bands of Mn(VII) are fully covered by the excitation bands of Tyloxapol. Next, another turn-on sensing application of the Tyloxapol/MnO4− platform to probe S2− against various other anions and aldehydes against various other organic pollutants were also established. It is expected that our strategy may offer a new approach for developing a simple, cost-effective, rapid and sensitive sensor for the detection of anions and aldehydes in environmental applications.

Three-dimensional (3D) hierarchical nanostructures have generated a large amount of interest because of their unique, unusual properties and potential applications. In this article, copper(II) ions as the inorganic component and various biosurfactants as the organic component were used to successfully form 3D nanoflowers via a facile and effective self-assembly template synthesis strategy. It can be confirmed that the biosurfactant molecules can first form complexes with the copper ions, and these complexes then become nucleation sites for primary crystals of copper phosphate, indicating that the interaction between biosurfactant and copper ions leads to the formation of 3D nanoflowers. Several reaction parameters such as aging time and the concentration of the biosurfactant, which play a critical role in the formation process and morphologies of the nanoflowers, were investigated. Under the optimum synthetic conditions, a spherical flowerlike structure with hundreds of nanopetals was obtained. Moreover, the biosurfactant–Cu3(PO4)2·3H2O nanoflowers also showed high stability and catalytic activity for degradation of cationic dyes. Our results demonstrate that the biosurfactant–inorganic 3D nanoflowers, which combined the advantages of the biosurfactant and inorganic material, have potential applications in industrial biocatalysis, biosensors, and environmental chemistry.

In this work, through the aqueous phase self-assembly of an Eu-containing polyoxometalate (POM), Na9[EuW10O36]·32H2O (EuW10) and different amino acids, we obtained spontaneously formed vesicles that showed luminescence enhancement for EuW10 and arginine (Arg), lysine (Lys), or histidine (His) complexes, but luminescence quenching for EuW10 and glutamic acid (Glu) or aspartic acid (Asp) complexes. The binding mechanisms between them have been explored at the molecular level by using different characterization techniques. It was found that EuW10 acted as polar head groups interact with the positively charged residues for alkaline amino acids, protonated amide groups for acidic amino and nonpolar acid aminos through electrostatic interactions, and the remaining segments of amino acids served as relatively hydrophobic parts aggregated together forming bilayer membrane structures. Moreover, the different influences of amino acids on the fluorescence property of EuW10 revealed that the electrostatic interaction...

In this article, welan gum–graphene oxide (GO) composite hydrogels were prepared by simple self-assembly of these two components in aqueous media and the effects of pH on their properties were systematically studied. The welan gum–GO hybrid hydrogels with different pH have been thoroughly characterized using TEM, FE-SEM, FT-IR spectroscopy, XRD and rheological measurements. It can be observed that the microstructures of welan–gum hydrogels can be tailored by varying the pH value and swelling properties analysis shows that the swelling ratio increases with pH. Moreover, the welan gum–GO hybrid hydrogels exhibited improved adsorption properties for water-soluble dyes under acidic conditions than under basic conditions. At the same time, adsorption isotherms and kinetics were also studied. Thus, it is expected that the GO-based composite hydrogels can act as potential adsorbents and have promising applications in the field of waste water treatment by adjusting pH.

In this article, a sensitive and selective turn-off fluorescence chemosensor, Tyloxapol (one kind of water soluble oligomer), was developed for the label-free detection of Fe(3+) ions in aqueous solution. Fluorescence (FL) experiments demonstrated that Tyloxapol was a sensitive and selective fluorescence sensor for the detection of Fe(3+) directly in water over a wide range of metal cations including Na(+), K(+), Ag(+), Hg(2+), Cd(2+), Co(2+), Cu(2+), Cr(3+), Mn(2+), Ba(2+), Zn(2+), Ni(2+), Mg(2+), Ca(2+), and Pb(2+). Moreover, the fluorescence intensity of Tyloxapol has shown a linear response to Fe(3+) in the concentration range of 0-100 μmol L(-1) with a detection limit of 2.2 μmol L(-1) in aqueous solution. Next, based on a competition mechanism, another turn-on sensing application of the Tyloxapol/Fe(3+) platform to probe dopamine (DA) against various other biological molecules such as other neurotransmitters or amino acids (norepinephrine bitartrate, acetylcholine chloride, alanine, valine, phenylalanine, tyrosine, leucine, glycine, histidine) were also investigated. It is expected that our strategy may offer a new approach for developing simple, cost-effective, rapid and sensitive sensors in biological and environmental applications.