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Hydrogen peroxide (H2O2) is an important product generated in the body and related to many pathophysiological processes and glucose metabolism disorder can cause many fatal diseases in living bodies. Therefore, the sensing of H2O2 and glucose is of great significance in disease diagnostics and treatment. Fluorescent carbon dots (CDs) are one new class of nanoprobes for H2O2 and glucose. Nevertheless, the CD-based sensor is always based on its fluorescence response, which is influenced by the auto-fluorescent interference. Herein, efficient fluorescent CDs were synthesized by one-pot solvothermal method, and the CDs exhibit bright and persistent deep-red (DR) chemiluminescence (CL) in bis(2,4,6-trichlorophenyl) oxalate and H2O2 solution with a CL quantum yield of (8.22 ± 0.30) × 10−3, which is amongst the highest values in ever reported nanomaterials for chemical analysis. Employing the CDs as CL nanoprobes, sensitive sensing for H2O2 has been achieved with a detection limit of 11.7 μM, and further for glucose detection with a detection limit of 12.6 μM. The DR CL CDs is promising to be applied in blood glucose analysis or in vivo biosensor.

Carbon nanogels (CNGs) with dual ability of reactive oxygen species (ROS) imaging and photodynamic therapy have been designed with self‐assembled chemiluminescent carbonized polymer dots (CPDs). With efficient deep‐red/near‐infrared chemiluminescence (CL) emission and distinctive photodynamic capacity, the H2O2‐driven chemiluminescent CNGs are further designed by assembling the polymeric conjugate and CL donors, enabling an in vitro and in vivo ROS bioimaging capability in animal inflammation models and a high‐performance therapy for xenograft tumors. Mechanistically, ROS generated in inflammatory sites or tumor microenvironment can trigger the chemically initiated electron exchange luminescence in the chemical reaction of peroxalate and H2O2, enabling in vivo CL imaging. Meanwhile, part of the excited‐state electrons will transfer to the ambient H2O or dissolved oxygen and in turn lead to the type I and type II photochemical ROS production of hydroxyl radicals or singlet oxygen, endowing the apoptosis of tumor cells and thus enabling cancer therapy. These results open up a new avenue for the design of multifunctional nanomaterials for bioimaging and antienoplastic agents. [ABSTRACT FROM AUTHOR]

Reactive oxygen species (ROS) are generated in the body and related to many pathophysiological processes. Hence, detection of ROS is indispensable in understanding, diagnosis, and treatment of many diseases. Here, near‐infrared (NIR) chemiluminescent (CL) carbon nanodots (CDs) are fabricated for the first time and their CL quantum yield can reach 9.98 × 10−3 einstein mol−1, which is the highest value ever reported for CDs until now. Nanointegration of NIR CDs and peroxalate (P‐CDs) through the bridging effect of amphiphilic triblock copolymer can serve as turn‐on probes for the detection and imaging of hydrogen peroxide (H2O2). Considering high efficiency and large penetration depth of NIR photons, the P‐CDs are employed in bioimaging H2O2 in vitro and in vivo, and the detection limit can reach 5 × 10−9m, among the best reported of CDs‐based sensors. Moreover, imaging of inflammatory H2O2 in a mouse model of peritonitis is achieved by employing the P‐CDs as sensors. The results may provide a clue for the diagnosis and treatment of inflammation or cancers employing CL CDs as sensors. [ABSTRACT FROM AUTHOR]

• Chemiluminescent properties and synthetic route of carbon dots are discussed. • Possible mechanism and recent advance in related applications of chemiluminescent carbon dots are identified. • Challenge and prospect in the future development of chemiluminescent CDs are considered. As one of important approaches of light emission, chemiluminescence (CL) induced by chemical reactions has evoked considerable interest for its potential applications in chemical detection, bioanalysis, and cold light source. Carbon dots (CDs) are one kind of emerging carbon nanomaterials for promising CL due to their unique luminescent properties, such as high fluorescence quantum yield, tunable emission wavelength, high photostability, etc. With the special physicochemical property, CDs can take part in the CL reaction as oxidants, emitting species, energy acceptors of chemical reaction energy or even catalysis involving in different CL systems. With these novel influences in CL reaction, these CD-related CL systems have been applied in a broad range of areas. For the reason, CL CDs and their applications such as CL emitting species, catalyst, sensor, information encryption, photodynamic therapy and in-vitro and in-vivo bioimaging/biosensor are reviewed and discussed in this paper. Meanwhile, the challenges and future prospects of the CL CDs have been discussed and proposed. [ABSTRACT FROM AUTHOR]

The various luminescent properties of carbon nanodots (CDs) reveal fascinating applications in several areas. Here, bright and multicolor chemiluminescence (CL) is realized from CDs, whose CL quantum yield can be optimized by adjusting the energy level alignment between the CDs and 1,2‐dioxetanedione intermediate generated from the reaction of peroxalate and hydrogen peroxide. A CL quantum yield of 9.32 × 10−3 Einsteins mol−1, maximal luminance of 3.28 cd m−2, and lifetime of 186.4 s are achieved in red CDs, all of which are the best values ever reported for CDs. As a proof‐of‐concept prototype, a high‐quality information encryption strategy is established via CD based CL imaging techniques by virtue of the high brightness and multicolor CL. [ABSTRACT FROM AUTHOR]

[Display omitted] • CL quenching is observed due to water-induced aggregation and energy transfer. • Surface chemical engineering is first attempted to improve CL performance of CDs. • CDs modified by n-butylamine exhibit a CL performance outperforming the commercial dyes. Carbon nanodots (CDs) are emerging as low toxic chemiluminescent (CL) materials for new-generation cold lighting and bioimaging technology due to their tunable and efficient emissions. Nevertheless, continuous progress and efforts are still needed to improve the luminance and lifetime of the CL CDs. Here, CL quenching is observed in the CD-peroxyoxalate-hydrogen peroxide system, resulting from the water-induced aggregation and blocking effect of the electron exchange between the CDs and energetic intermediate produced in the CL reaction. A surface chemical regulation strategy is first introduced to improve the CL performance of CDs. Optimized the capped ligand species and chain length, the CDs modified by n-butylamine exhibit a CL quantum yield of 1.15 × 10–2 einsteins mol−1 and maximal luminance of 5.11 cd m−2, which is about 5- and 13-fold higher than the initial CDs and comparable with commercially available Rhodamine B. The enhanced performance can be explained by the decreased electron capture from water molecules generated due to the decomposition of hydrogen peroxide in the CL process. [ABSTRACT FROM AUTHOR]

Quadruple-mode emitting carbon nanodots (QM-CDs) have been designed via an ionic crystal confining strategy. The results reveal that the high-density ionic bonds can inactivate the nonradiative defect centers, stabilize triplet excitons, increase the cross-sectional absorption and boost the chemiluminescence resonance energy transfer of the QM-CDs, endowing their efficient fluorescence, upconversion photoluminescence, phosphorescence, and chemiluminescence simultaneously. And the confining aggregation of CDs in the NaOH matrix contribute to the tunable light emission wavelength. With the QM-CDs, one kind of all-photonic multiple-inputs logic gates with programmable emitting modes have been established to achieve information processing and security. [Display omitted] • The QM-CDs with tunable multiple-mode light emitting are prepared. • The high-density ionic bonds endow the multiple-mode light emitting of QM-CDs. • The confining aggregation endow the tunable light emission wavelengths of QM-CDs. • The programmable multiple-inputs logic gates are established with the QM-CDs. Multiple-mode light emitting in one material system is tremendous desirable for various applications. Herein, we have developed an ionic crystal confining strategy to prepare the carbon nanodots (CDs) with quadruple-mode light emitting and demonstrated their promising application in information anti-counterfeiting via optical logic gates. In detail, the quadruple-mode light emitting of CDs (QM-CDs) are prepared with the citric acid and urea with NaOH matrix via microwave-assisted polymerization. Mechanically, the high-density ionic bonds stemmed from the NaOH ionic-crystal can effectively inactivate nonradiative defect centers, stabilize triplet excitons, increase absorption cross-section and boost resonance energy transfer, evoking the outstanding solid-state fluorescence, upconversion photoluminescence (UCPL), phosphorescence, and chemiluminescence simultaneously. Meanwhile, the isolated NaOH matrix can promote the confining aggregation of CDs, leading to the redshifted emission wavelength and endowing the light emitting with tunable wavelength. With the excitability of logic functions between the light emitting and controlled excitation, the programmable multiple-inputs logic gates are established with the QM-CDs, enabling the application in high-throughput logical operations and information anti-counterfeiting. This research provides a new insight into the synthesize of multiple-mode luminescent CDs, and thus promote the applications of nanomaterials in intelligent encryption and anti-counterfeiting. [ABSTRACT FROM AUTHOR]

Chemiluminescence (CL) induced by peroxalate fuel and hydrogen peroxide has been widely applied in chemical detection and bioimaging. Nevertheless, the chemiluminescent emitters in the CL are focused on organic small-molecular dyes, most of which encounter serious obstacles in practical application due to their potential biotoxicity and low photostability. Here, bright blue CL is observed when biocompatible zinc oxide nanoparticles (ZnO NPs) with yellow photoluminescence (PL) are added into peroxalate and hydrogen peroxide solution, which is originated from the interaction between the zinc interstitial of ZnO NPs and the energy-rich intermediate produced in the CL process. With the modification of silane coupler, the CL quantum yield of ZnO NPs presents two orders of magnitude increase from 6.2× 10−6 to record 3.7 × 10−4 E⋅mol−1 for inorganic NPs owing to the protective effect from silicon oxide shell layer. By virtual of excellent CL ability, ZnO NPs have been firstly used as CL probes in bioimaging, which opens the way to a new design freedom for biosensor or bioimaging in the future. • Chemiluminiscence quantum yield of ZnO NPs with silane shell presents two orders of magnitude increase. • ZnO NPs with silane shell show the highest chemiluminiscence quantum yield value for the inorganic NPs. • ZnO NPs have been served as CL probes in bioimaging for the first time. • The chemiluminiscence of ZnO NPs has been clarified through the chemically initiated electron exchange. • The excitation electron of ZnO can transit from the zinc interstitial atom energy level to valence band and emit blue light. [ABSTRACT FROM AUTHOR]