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Under the acidic conditions (pH 4.0), the addition of wheat oligopeptides (WOPs) (25~100 g/L) decreased the thermal stability of purple sweet potato anthocyanins (PSPAs), but enhanced its antioxidant capacity, which increased with the rise of the additive amount. When the addition was 100 g/L, the DPPH, ABTS free radical scavenging capacity and FRAP total antioxidant capacity of PSPAs solution after in vitro simulated digestion were increased by 1.5 times, 34 times and 34%, respectively. After storage at 37 ℃ and 45 ℃ for 7 d, the antioxidant capacity did not change significantly, and it had stronger biological activity and higher stability than those of PSPAs. UV and fluorescence spectra showed that PSPAs can affected the redshift of absorption peak and fluorescence quenching at specific wavelength of WOPs at experimental concentration, which proved the interaction between WOPs and PSPAs. It can be seen from the above that WOPs have the potential to be applied in the development of acidic PSPAs beverages.

In order to improve the gel properties of black rice, mung bean starch, potato starch and corn starch were mixed with black rice flour. The pasting properties and texture properties of compounded system, and the molecular structure characteristics of the complex system were tested, and further analyzed by low-field NMR analyzer, Fourier transform infrared spectroscopy and X-ray diffraction. The results showed that with the increase of starch concentration, the pasting viscosity of the starch-black rice flour complex system increased significantly, while the pasting time and temperature were reduced. Mung bean starch and potato starch significantly enhanced the water holding capacity and swelling capacity of the compound system, while potato starch and corn starch significantly reduced the solubility. All three starches promoted the formation of the gel network structure and improved the texture properties of the gel, including the hardness, elasticity, chewiness and resilience of the gel. In addition, the three starches enhanced the hydrogen bond interaction between the starch chains of the compound system, reduced the water holding capacity of the gel, and enhanced the molecular short-range structure order and relative crystallinity of the system. The above research showed that three kinds of starch improved the quality of black rice gel, and mung bean starch had the best improvement effect.

We herein present an approach of photo‐induced disproportionation for preparation of Type‐I photodynamic agents. As a proof of concept, BODIPY‐based photosensitizers were rationally designed and prepared. The photo‐induced intermolecular electron transfer between homotypic chromophores leads to the disproportionation reaction, resulting in the formation of charged intermediates, cationic and anionic radicals. The cationic radicals efficiently oxidize the cellularimportant coenzyme, tetrahydrobiopterin (BH4), and the anionic radicals transfer electrons to oxygen to produce superoxide radicals (O2−⋅). One of our Type‐I photodynamic agents not only self‐assembles in water but also effectively targets the endoplasmic reticulum. It displayed excellent photocytotoxicity even in highly hypoxic environments (2 % O2), with a half‐maximal inhibitory concentration (IC50) of 0.96 μM, and demonstrated outstanding antitumor efficacy in murine models bearing HeLa tumors. [ABSTRACT FROM AUTHOR]

Chirality, with its intrinsic symmetry‐breaking feature, is frequently utilized in the creation of acentric crystalline functional materials that exhibit intriguing optoelectronic properties. On the other hand, the development of chiral crystals from achiral molecules offers a solution that bypasses the need for enantiopure motifs, presenting a promising alternative and thereby expanding the possibilities of the self‐assembly toolkit. Nevertheless, the rational design of achiral molecules that prefer spontaneous symmetry breaking during crystallization has so far been obscure. In this study, we present a series of six achiral molecules, demonstrating that when these conformationally flexible molecules adopt a cis‐conformation and engage in multiple non‐covalent interactions along a helical path, they collectively self‐assemble into chiral superstructures consisting of single‐handed supramolecular columns. When these homochiral supramolecular columns align in parallel, they form polar crystals that exhibit intense luminescence upon grinding or scraping. We therefore demonstrate our molecular design strategy could significantly increase the likelihood of symmetry breaking in achiral molecular synthons during self‐assembly, offering a facile access to novel chiral crystalline materials with unique optoelectronic properties. [ABSTRACT FROM AUTHOR]

A multifunctional undecapeptide, YYDPLGLADYY, was designed and synthesized for the photowrapping of silica-coated gold nanorods. The obtained nanocapsules, bearing a well-defined core–shell structure, were able to encapsulate a therapeutic drug, respond to an MMP-upregulated tumor microenvironment, and achieve NIR-triggered anticancer chemo-photothermal therapy with favorable efficacy. [ABSTRACT FROM AUTHOR]

We report a multi-stimuli-responsive luminescent material containing rotor moieties. It forms two types of crystals, G and O. The emission of G can be modulated by multiple external stimuli, whereas O does not show such responsiveness. The X-ray structure analysis reveals that the rotors are critical for the polymorphic emission and stimuli response properties. [ABSTRACT FROM AUTHOR]

Without external chiral intervention, it is a challenge to form homochirality from achiral molecules with conformational flexibility. We here report on a rational strategy that uses multivalent noncovalent interactions to clamp the molecular conformations of achiral D‐A molecules. These interactions overcome the otherwise dominant dipole‐dipole interactions and thus disfavor their symmetric antiparallel stacking. It in turn facilitates parallel packing, leading to spontaneous symmetry breaking during crystallization and thus the formation of homochiral conglomerates. When this emergent homochirality is coupled with optical gain characteristics of the molecules, the homochiral crystals are explored as excellent circularly polarized micro‐lasers with low lasing threshold (16.4 μJ cm−2) and high dissymmetry factor glum (0.9). This study therefore provides a facile design strategy for supramolecular chiral materials and active laser ones without the necessity of intrinsic chiral element. [ABSTRACT FROM AUTHOR]

We report J-aggregates of a boron dipyrromethene derivative (BDP-Nit) as an H2S-activatable nano-photosensitizer. The closely packed BDP-Nit in J-aggregates exhibits high selectivity to H2S over biothiols to produce an active photosensitizer. [ABSTRACT FROM AUTHOR]

We report N,O-boron-chelated dipyrromethene derivatives exhibiting circularly polarized luminescence (CPL) in the red/near-infrared region, both in solution and the aggregated state. The CPL is originated from the helical chirality through intramolecular substitution of fluorine by an alkenolic substituent. The self-assembly of the fluorophores significantly enhances the ‖glum‖ values from 10−4 to 10−2. [ABSTRACT FROM AUTHOR]

Developing Type‐I photosensitizers is considered as an efficient approach to overcome the deficiency of traditional photodynamic therapy (PDT) for hypoxic tumors. However, it remains a challenge to design photosensitizers for generating reactive oxygen species by the Type‐I process. Herein, we report a series of α,β‐linked BODIPY dimers and a trimer that exclusively generate superoxide radical (O2−.) by the Type‐I process upon light irradiation. The triplet formation originates from an effective excited‐state relaxation from the initially populated singlet (S1) to triplet (T1) states via an intermediate triplet (T2) state. The low reduction potential and ultralong lifetime of the T1 state facilitate the efficient generation of O2−. by inter‐molecular charge transfer to molecular oxygen. The energy gap of T1‐S0 is smaller than that between 3O2 and 1O2 thereby precluding the generation of singlet oxygen by the Type‐II process. The trimer exhibits superior PDT performance under the hypoxic environment. [ABSTRACT FROM AUTHOR]

An organic crystal of 4,4′‐bis(N‐carbazolyl)‐1,1′‐biphenyl (pCBP) exhibits time‐dependent afterglow color from blue to orange over 1 s. Both experimental and computational data confirm that the color evolution results from well‐separated, long‐persistent thermally activated delayed fluorescence (TADF) and room‐temperature phosphorescence (RTP) with different but comparable decay rates. TADF is enabled by a small S1–T1 energy gap of 0.7 kcal mol−1. The good separation of TADF and RTP is due to a 11.8 kcal mol−1 difference in the S0 energies of the S1 and T1 structures, indicating that apart from the excited‐state properties, tuning the ground state is also important for luminescence properties. This afterglow color evolution of pCBP allows its applications in anticounterfeiting and data encryption with high security levels. [ABSTRACT FROM AUTHOR]

We report a series of difluoroboron β-diketonate fluorophores that manifest temperature-dependent emission wavelength accompanied by a change of fluorescence from green to orange. The distinct emission changes allow convenient and accurate measurements of temperature. [ABSTRACT FROM AUTHOR]

SO2, an important gasotransmitter, plays significant roles in human physiological activities. The reported probes for the detection of SO2 derivatives are mostly based on the quenching or blue-shift of fluorescence, leading to interference from the background signal. Herein, we develop a novel FRET-based nanoprobe that shows turn-on fluorescence at 615 nm in the presence of SO32−/HSO3−. The nanoprobe consists of N,O,B-chelated dipyrromethene (BDP) as the energy donor, and hemicyanine derivatives of HEM-CO-Ph with a responsive site to SO32−/HSO3− as the energy acceptor. Initially, the fluorescence of BDP is quenched by HEM-CO-Ph due to the efficient FRET process. In the presence of sulfites, the nucleophilic addition interrupts the conjugation of HEM-CO-Ph and results in a 200 nm blue-shift of the absorption, leading to the suppression of the FRET process and recovery of the red fluorescence of BDP. The nanoprobe shows fast response to SO32−/HSO3− with high selectivity, great biocompatibility and cellular uptake. It is the first supramolecular nanoprobe for the detection of SO32−/HSO3− by using intermolecular energy transfer, ingeniously turning the nanoprobe from "OFF" state to "ON" state. The nanoprobe is applied to monitor exogenous and endogenous SO2 derivatives in the mitochondria of living cells. [ABSTRACT FROM AUTHOR]

We report an unexpected coupling–reduction tandem reaction as a general and efficient one-pot synthesis of alkenyl-substituted boron dipyrromethene (BODIPY) from chlorinated-BODIPY and alkyne. This unique synthesis combined the Sonogashira coupling reaction and reduction reaction without adding an additional reagent, which shows higher yields, broader substrate scope and faster reaction rate compared with the conventional methods of the Knoevenagel reaction and Heck coupling reaction. [ABSTRACT FROM AUTHOR]

We report a series of organic fluorophores that undergo selective self-sensitized photooxidation upon light irradiation in air accompanied by a change of fluorescence from yellow to blue on the seconds timescale. The distinct emission changes allow the ratiometric quantitation of O2 concentration. [ABSTRACT FROM AUTHOR]

Abstract: The first example of the synthesis of mono‐N,O‐B‐chelated dipyrromethene (BODIPY) derivatives through an unexpected intramolecular nucleophilic displacement of the fluorine by alkenols in the presence of boron trifluoride as Lewis acid is reported. The chlorine in the indacene core allowed for further structural modifications through nucleophilic substitutions or palladium‐catalysed coupling reactions to afford new fluorophores with tuneable photophysical properties. Their expanded conjugation structure resulted in distinct red‐shifted absorption and emission spectra in organic solutions. Furthermore, the twisted steric hindrance of the benzene substitution patterns suppressed aggregation‐induced quenching, leading to an enhanced NIR emission in the aggregate/solid state, which was rarely observed for BODIPY dyes. Nanoparticles of the fluorophores formed by the assembly with the polymeric surfactant F127 were successfully used for bioimaging of living cells and for tumour‐targeted imaging in a tumour‐bearing mouse model. [ABSTRACT FROM AUTHOR]

We report a new molecular design for optically triggered nm-scale translation of a submolecular component relative to another. We used a rotaxane-like molecule terminated at one end with stiff stilbene that served both as a chromophore to trigger the translation of the pillar[5]arene “wheel” and as a stopper to prevent its dethreading. [ABSTRACT FROM AUTHOR]

We report a fluorescent nanoprobe based on the co-assembly of amphiphilic BODIPY and fluorescein for selective detection of GSH. The amphiphilic BODIPY derivative, consisting of hydrophobic BODIPY unit and hydrophilic PEG chains, co-assembled with fluorescein to give non-fluorescent nanoparticles due to the aggregation caused quenching. Upon addition of GSH, the thiol group of GSH reacted with BODIPY through nucleophilic substitution to afford highly polar GSH-substituted BODIPY with high solubility in water, resulting in the disassembly of the nanoparticles. The GSH-induced disassembly of the nanoparticles released the highly fluorescent BODIPY derivative and fluorescein, enabling the dual-emissive detection of GSH. This nanoprobe was applied for the dual-channel fluorescence imaging of GSH in living cells. [ABSTRACT FROM AUTHOR]

Artificial light-harvesting nanoparticles were prepared from supramolecular polymers comprised of pillar[5]arene with anthracene-derived donors and acceptors through host–guest interactions. The resulting water-dispersible nanoparticles displayed efficient energy transfer and excellent light harvesting ability in part because the steric bulk of pillar[5]arene suppressed the self-quenching of the chromophores. [ABSTRACT FROM AUTHOR]