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This review summarizes the works regarding chiral inorganic nanomaterials with bio-functions and bio-applications, which can deep our understanding on chiral inorganic nanomaterials' construction principles and biological functional properties.

Color-changeable indicators for information readouts upon the combination of trivalent bismuth and lanthanides ions.

A near-infrared fluorescent nanoprobe based on semiconducting polymer nanoparticles with lysosome locating capacity for the detection and visualization of senescence-associated β-gal in living cells is developed.

Clinical exome sequencing has yielded extensive disease-related missense single-nucleotide variants (SNVs) of uncertain significance, leading to diagnostic uncertainty. KCNQ4 is one of the most commonly responsible genes for autosomal dominant nonsyndromic hearing loss. According to the gnomAD cohort, approximately one in 100 people harbors missense variants in KCNQ4 (missense variants with minor allele frequency > 0.1% were excluded), but most are of unknown consequence. To prospectively characterize the function of all 4085 possible missense SNVs of human KCNQ4, we recorded the whole-cell currents using the patch-clamp technique and categorized 1068 missense SNVs as loss of function, as well as 728 loss-of-function SNVs located in the transmembrane domains. Further, to mimic the heterozygous condition in Deafness nonsyndromic autosomal dominant 2 (DFNA2) patients caused by KCNQ4 variants, we coexpressed loss-of-function variants with wild-type KCNQ4 and found 516 variants showed impaired or only partially rescued heterogeneous channel function. Overall, our functional classification is highly concordant with the auditory phenotypes in Kcnq4 mutant mice and the assessments of pathogenicity in clinical variant interpretations. Taken together, our results provide strong functional evidence to support the pathogenicity classification of newly discovered KCNQ4 missense variants in clinical genetic testing.

For harmonizing the contradiction of nanotheranostic agents between enhanced tumor accumulation and penetration, efficient cell internalization and fast elimination are key tactics for promoting their clinical applications. Herein, programmed stimuli-responsive poly(

The feasibility of chemical unit co-substitution in developing new NIR persistent phosphors is demonstrated, which can motivate further exploration of luminescent materials with novel properties.

Carbon dots (CDs), as a new member of carbon nanostructures, have been widely applied in extensive fields due to their exceptional physicochemical properties. While, the emissions of most reported CDs are located in the blue to green range under the excitation of ultraviolet or blue light, which severely limits their practical applications, especially in photovoltaic and biological fields. Studies that focused on synthesizing CDs with long-wavelength (red to near-infrared) emission/excitation features (simply named L-w CDs) and exploring their potential applications have been frequently reported in recent years. In this review, we analyzed the key influence factors for the synthesis of CDs with long wavelength and multicolor (containing long wavelength) emissive properties, discussed possible fluorescence mechanism, and summarized their applications in sensing and cancer theranostics. Finally, the existing challenges and potential opportunities of L-w CDs are presented.

Highlights A facile method was developed to achieve visible light (green) and near infrared dual-mode afterglow emissions from carbon dots (CDs)-based materials at ambient conditions for the first time.We proposed a promising method in advanced information security applications through a special manner of readout.The as-developed method was confirmed to be applicable to many kinds of CDs for achieving or enhancing their afterglow performances. Supplementary Information The online version contains supplementary material available at 10.1007/s40820-021-00718-z., Near-infrared (NIR), particularly NIR-containing dual-/multi-mode afterglow, is very attractive in many fields of application, but it is still a great challenge to achieve such property of materials. Herein, we report a facile method to prepare green and NIR dual-mode afterglow of carbon dots (CDs) through in situ embedding o-CDs (being prepared from o-phenylenediamine) into cyanuric acid (CA) matrix (named o-CDs@CA). Further studies reveal that the green and NIR afterglows of o-CDs@CA originate from thermal activated delayed fluorescence (TADF) and room temperature phosphorescence (RTP) of o-CDs, respectively. In addition, the formation of covalent bonds between o-CDs and CA, and the presence of multiple fixation and rigid effects to the triplet states of o-CDs are confirmed to be critical for activating the observed dual-mode afterglow. Due to the shorter lifetime and insensitiveness to human vision of the NIR RTP of o-CDs@CA, it is completely covered by the green TADF during directly observing. The NIR RTP signal, however, can be readily captured if an optical filter (cut-off wavelength of 600 nm) being used. By utilizing these unique features, the applications of o-CDs@CA in anti-counterfeiting and information encryption have been demonstrated with great confidentiality. Finally, the as-developed method was confirmed to be applicable to many other kinds of CDs for achieving or enhancing their afterglow performances. Supplementary Information The online version contains supplementary material available at 10.1007/s40820-021-00718-z.

Poor tumor specificity is one of the key obstacles for clinical applications of nanotheranostic agents, consequently leading to serious side effects and unsatisfactory therapeutic efficacy. Herein, biomolecule-based nanohybrids (named as Hb-PDA-GOx) with multiple stimuli-responsiveness were designed and fabricated to enhance tumor-specific therapy. The nanohybrids embodied two proteins, i.e., hemoglobin (Hb) and glucose oxidase (GOx), which exhibited cascade catalytic activity selectively within the tumor microenvironment (TME). Specifically, GOx catalyzes the overexpressed glucose into gluconic acid and hydrogen peroxide (H

We herein report a facile method to fabricate a multifunctional cancer theranostic nanoplatform via Fe3+-driven assembly of photosensitizer (chlorine e6, Ce6)-decorated red emissive carbon dots (Ce...

Color-tunable ultralong phosphorescence is urgently desired in optoelectronic applications. Herein, we report a new type of full-color-tunable ultralong phosphorescence carbon dots (CDs) without matrix-assistance by a self-doping method under ambient conditions. The phosphorescence color can be rationally tuned from blue to red by changing the excitation wavelength from 310 to 440 nm. The CDs exhibit an ultralong lifetime of up to 1052.23 ms at 484 nm. From the experimental data, we speculate that the excitation-dependent multi-color phosphorescence is attributed to the presence of multiple emitting centers related to carbonyl units. Given the unique color-tunability of CDs, we demonstrate their potential applications in information encryption, light detection ranging from UV to visible light and LED devices. This finding not only takes a step towards the fundamental design of full-color emissive materials, but also provides a broader scope for the applications of phosphorescent materials.

We herein report a facile method to fabricate a multifunctional cancer theranostic nanoplatform via Fe

The trap distribution due to defects in persistent luminescent materials plays a significant role in their scope of applications. However, it is a big challenge to manipulate or modulate this trap distribution. In this work, the trap distribution of green emitting persistent phosphor Li2ZnGeO4:Mn2+ is modulated upon a facile microwave-assisted solid-state reaction. A series of systematic temperature dependent trapping, de-trapping and re-trapping measurements are designed to shed light on trap information. An appealing feature of the present synthesis approach is that the trap distribution is modulated towards shallow traps, which offers great promise in low-temperature glow-in-the-dark applications. More importantly, trap re-shuffling can be achieved towards two directions, both lower energy level (shallow traps) and higher energy levels (deep traps) upon light stimulation. These findings indicate there are optically active trapping defects with photo-stimulated re-trapping behavior in this persistent phosphor. This work not only provides a fundamental advance in revealing re-trapping behavior, but also offers a guidance for the modulation of trap distribution in persistent phosphors upon a facile approach.

A method is developed to fabricate tumor microenvironment (TME) stimuli-responsive nanoplatform for fluorescence (FL) imaging and synergistic cancer therapy via assembling photosensitizer (chlorine e6, Ce6) modified carbon dots (CDs-Ce6) and Cu2+ . The as-obtained nanoassemblies (named Cu/CC nanoparticles, NPs) exhibit quenched FL and photosensitization due to the aggregation of CDs-Ce6. Their FL imaging and photodynamic therapy (PDT) functions are recovered efficiently once they entering tumor sites by the stimulation of TME. Introducing of Cu2+ not only provides extra chemodynamic therapy (CDT) function through reaction with hydrogen peroxide (H2 O2 ), but also depletes GSH in tumors by a redox reaction, thus amplifying the intracellular oxidative stress and enhancing the efficacy of reactive oxygen species (ROS) based therapy. Cu/CC NPs can act as a FL imaging guided trimodal synergistic cancer treatment agent by photothermal therapy (PTT), PDT, and thermally amplified CDT.

As a newly emerged carbon-based luminescent nanomaterial, carbon dots (CDs) have attracted considerable attention due to their outstanding features. Their photoluminescence (PL) properties and relevant applications have been extensively studied and reviewed in recent years. However, although their afterglow feature had also been discovered and had seen some important advances, no review article was published to systematically summarize such advances. Considering the scientific importance and promising applications of afterglow materials, herein, we aim to summarize the recent remarkable advances of the afterglow phenomena of CDs, particularly focusing on their room temperature phosphorescence (RTP) and thermally activated delayed fluorescence (TADF). This review will firstly simply introduce the classification of CDs, and then provide comprehensive discussions regarding the relationships between their structure and afterglow properties. Furthermore, their potential applications in anti-counterfeiting, information protection, sensing, etc., are summarized. Finally, challenges and opportunities in the future of this newly emerged carbon-based afterglow material are proposed.

Although some colorimetric sensor arrays have been developed for the identification of Chinese liquors, they usually require the confirmation of volatile markers in the liquors by chromatography and mass spectrometry firstly. Herein, we present a simple colorimetric sensor array to identify various Chinese liquors in the liquid phase without the aid of other analytical techniques. The colorimetric sensor array consists of six commercially available and inexpensive solvatochromic dyes, and the sensing mechanism of this array is based on the response of solvatochromic dyes to their local polarity. On the basis of the colour changes of the sensor array, different Chinese liquors are discerned readily using pattern recognition methods, and the statistical analysis results (i.e., hierarchical clustering analysis and principal component analysis) reveal that the as-fabricated sensor array can distinguish the subtle differences between different liquors from the same winery and the same flavor type. Moreover, the developed sensor array can even distinguish diverse diluted liquors from the pristine ones.

Herein, we report a turn-on fluorimetric nanoprobe for intracellular glutathione (GSH) imaging. The principle of this probe is designed on the basis of the selective reduction between GSH and disulfide bond-based self-crosslinked red emissive carbon dots (abbreviated as SCCDs). The nanoprobe (i.e., SCCDs) was facilely fabricated from thiol-modified carbon dots (CDs) through oxidation in the presence of H2O2, and its fluorescence was greatly reduced due to the effect of aggregation induced quenching (AIQ). However, in the presence of GSH, the SCCDs were separated into many single CDs. As a result, the fluorescence of the nanoprobe was recovered in a GSH concentration-dependent manner, which is the basis for the quantitative analysis of GSH. The nanoprobe shows excellent specificity and a linear range from 0 to 0.15 mM towards GSH with a limit of detection (LOD) of 5.7 μM. Finally, the nanoprobe was demonstrated to have extremely low cytotoxicity, and was successfully applied for monitoring the GSH level in living cells. This work would provide a promising probe for the research of GSH in cytobiology.

The first carbon dot (CD)-based organic long persistent luminescence (OLPL) system exhibiting more than 1 h of duration was developed. In contrast to the established OLPL systems, herein, the reported CDs-based system (named m-CDs@CA) can be facilely and effectively fabricated using a household microwave oven, and more impressively, its LPL can be observed under ambient conditions and even in aqueous media. XRD and TEM characterizations, afterglow decay, time-resolved spectroscopy, and ESR analysis were performed, showing the successful composition of CDs and CA, the formation of exciplexes and long-lived charged-separated states. Further studies suggest that the production of covalent bonds between CA and CDs plays pivotal roles in activating LPL and preventing its quenching from oxygen and water. To the best of our knowledge, this is a very rare example of an OLPL system that exhibits hour-level afterglow under ambient conditions. Finally, applications of m-CDs@CA in glow-in-the-dark paints for emergency signs and multicolored luminous pearls were preliminarily demonstrated. This work may provide new insights for the development of rare-earth-free and robust OLPL materials.

Room-temperature phosphorescent carbon dots (RTP-CDs) may be used in anti-counterfeiting, information encryption, and optoelectronic devices, but modulating their triplet-state energy is still challenging. Here, a type of RTP-CDs was developed via hydrothermal polymerization-carbonization of azamacrocycle and poly(acrylic acid). The introduction of nitrogen heterocycle promotes the intersystem crossing from the singlet state to the triplet state, and the functional groups of CDs can form interdot hydrogen bonds to protect the triplet state. In addition, the uncarbonized heterocycle groups in the CDs provide coordination sites for metal ions. In this case, the excited triplet-state energy of CDs is quenched by paramagnetic ions (Co2+ and Cu2+) or transfers to luminescent ions (Tb3+ and Eu3+). Furthermore, the modulation of the triplet state by metal ion binding was demonstrated in information encryption and anti-counterfeiting applications.

The COVID-19 (coronavirus disease 2019) pandemic is caused by SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2). SARS-CoV-2 produces a small hydrophobic envelope (E) protein which shares high homology with SARS-CoV E protein. By patch-clamp recording, the E protein is demonstrated to be a cation-selective ion channel. Furthermore, the SARS-CoV-2 E protein can be blocked by a SARS-CoV E protein inhibitor hexamethylene amiloride. Using structural model and virtual screening, another E protein inhibitor AZD5153 is discovered. AZD5153 is a bromodomain protein 4 inhibitor against hematologic malignancies in clinical trial. The E protein amino acids Phe23 and Val29 are key determinants for AZD5153 sensitivity. This study provides two promising lead compounds and a functional assay of SARS-CoV-2 E protein for the future drug candidate discovery.

In this work, a bioprobe for the detection of dopamine was designed and fabricated through covalently linking fluorescent carbon dots (CDs) and tyrosinase (TYR). The bioprobe (named CDs-TYR) can catalyze oxidation of dopamine and produce dopaquinone, and consequently the fluorescence of the CDs was quenched due to an efficient electron transfer mechanism from excited CDs to dopaquinone. The fluorescence intensity of CDs decreased in a dopamine-concentration-dependent manner, which built the foundation of dopamine quantification. The bioprobe provided a wide linear range from 0.1 to 6.0 μM for dopamine sensing. Additionally, excellent selectivity of the bioprobe to dopamine was achieved because of the specific catalytic character of the conjugated TYR. Furthermore, the bioprobe was successfully employed for the detection of dopamine in spiked human serum. To the best of our knowledge, this is the first example of the construction of a bioprobe through conjugating CDs and an enzyme. This work would open new opportunities to develop CD-based photoinduced electron transfer bioprobes for other analytes via linking typical enzymes onto CDs.

Carbon dots (CDs) with a room temperature phosphorescent (RTP) feature have attracted considerable interest in recent years due to their fundamental importance and promising applications. However, the reported matrix-free RTP CDs only show short-wavelength (green to yellow) emissions and have to be triggered by ultraviolet (UV) light (below 400 nm), limiting their applications in certain fields. Herein, visible-light-excited matrix-free RTP CDs (named AA-CDs) with a long-wavelength (orange) emission are reported for the first time. The AA-CDs can be facilely prepared via a microwave heating treatment of L-aspartic acid (AA) in the presence of ammonia and they emit unique orange RTP in the solid state with visible light (420 nm) excitation just being switched off. Through the studies of the carbonization process, the C=O and C=N containing moieties in the AA-CDs are confirmed to be responsible for the observed RTP emission. Finally, the applications of AA-CDs in information encryption and anti-counterfeiting were preliminarily demonstrated.

Pesticides play a critical role in improving crop yield in modern agriculture, but their residues significantly harm the environment and human health. Herein, a novel and simple colorimetric sensor array built on sulfuric acid assisted KMnO4 fading strategy has been developed for pesticides detection and discrimination. This sensor array is facilely fabricated by KMnO4 and sulfuric acid through simply adjusting their concentrations and ratios. Hierarchical clustering analysis (HCA) demonstrates that the as-fabricated colorimetric sensor array has a high dimensionality, and shows excellent capability to recognize common kinds of pesticides from potential interferants. Semi-quantitative detection was achieved through combining HCA and corresponding fitting curves. Moreover, the proposed sensor array was successfully applied to detect pesticide residues (e.g. carbaryl) in real samples. The strategy described herein will not only “maximally” simplify the design and fabrication approach, but expand the application fields of colorimetric sensor array methodology towards weak-reactive analytes.

Long-lifetime room-temperature phosphorescence (RTP) materials are important for many applications, but they are highly challenging materials owing to the spin-forbidden nature of triplet exciton transitions. Herein, a facile, quick and gram-scale method for the preparation of ultralong RTP (URTP) carbon dots (CDs) was developed via microwave-assisted heating of ethanolamine and phosphoric acid aqueous solution. The CDs exhibit the longest RTP lifetime, 1.46 s (more than 10 s to naked eye) for CDs-based materials to date. The doping of N and P elements is critical for the URTP which is considered to be favored by a n→π* transition facilitating intersystem crossing (ISC) for effectively populating triplet excitons. In addition, possibilities of formation of hydrogen bonds in the interior of the CDs may also play a significant role in producing RTP. Potential applications of the URTP CDs in the fields of anti-counterfeiting and information protection are proposed and demonstrated.

Photoacoustic imaging (PAI) has emerged as a promising clinical technology, thanks to its high-resolution in deep tissues. However, the lack of specificity towards analytes limits further application of the PA probe in molecular imaging. To this end, we herein report a PA and fluorescence (FL) dual-modal probe for the selective detection of ascorbic acid (AA). To realize this design, cobalt oxyhydroxide (CoOOH) was adopted as a multifunctional platform (PA contrast agent, FL quencher and specific oxidant to AA) and hybridized with red-emissive carbon dots (RCDs). In the presence of AA, CoOOH is reduced to Co2+ and meanwhile releases RCDs, resulting in the decrease of PA and recovery of FL signals. We demonstrated the AA detection capabilities of the probe in complicated biological fluids (human serum and urine), living cells, and dual-modal FL/PA imaging in vivo. This work revealed the PAI capacity of CoOOH for the first time, which may inspire researchers to design other CoOOH-based PA probes and further employ RCDs in biology and the clinic.

Near-infrared persistent luminescent materials have great potential for in vivo bioimaging and night-vision surveillance due to their long-lasting autofluorescence-free emission through deep tissues and multicycle photostimulated luminescence by releasing energy from captured traps using high-intensity 808 or 980 nm lasers. However, phosphors combining both near-infrared persistent luminescence and photostimulated luminescence are found mostly in chromium doped gallates hosts, other emitters are rarely reported. Herein, a new material system with near-infrared persistent luminescence is achieved in tetravalent manganese doped double-perovskite alkali-earth metal tungstates via the aliovalent substitution of calcium ions with lanthanum ions. Persistent luminescence can be generated via X-ray irradiation, providing great promise in long-term deep-tissue ultrasensitive imaging, information storage, and X-ray detection. Photostimulated detrapping is successfully demonstrated using a common 420 nm light emitting diode instead of a high-intensity 808 or 980 nm laser. The traps distribution is proved to be reshuffled upon this laser-free visible light stimulation. Reshuffling of trap distributions upon visible light stimulation may be promising for optical information storage applications. This work is expected to broaden the range of near-infrared persistent material systems and provides new insights into manipulating photostimulated traps via laser-free light stimulation.

A facile and high-efficient approach for the preparation of graphene quantum dots (GQDs) is reported. With the assistance of KO2 in the hydrothermal cutting graphene oxide (GO), a conversion rate of ∼35 wt% from GO to GQDs is achieved. The as-prepared GQDs display rarely observed yellow emissive photoluminescence with a respectable quantum yield of 8.9% in H2O. Moreover, the GQDs are further demonstrated to perform as a potential pH probe and bioimaging agent.

The authors describe a fluorometric nanoprobe for hypochlorite ion. It was prepared by covalently linking o-phenylenediamine to graphene quantum dots (GQDs). The probe displays green fluorescence with excitation/emission peaks at 440/534 nm. In the presence of chlorite, oPD is oxidized to form a quinone-iminium compound which induces a reduction in fluorescence intensity. The nanoprobe enables chlorite to be determined with a 69 nM limit of detection. The probe is highly selective, well water soluble and biocompatible. It was successfully employed in the determination of chlorite in spiked tap water and living cells. The method is believed to represent a promising tool for the determination of chlorite in environmental, biological and clinical samples.