Enhancement of periodate-hydrogen peroxide chemiluminescence by nitrogen doped carbon dots and its application for the determination of pyrogallol and gallic acid

Hydrogen peroxide enhanced glow-type chemiluminescence of hydrazine hydrate modified carbon quantum dots-potassium persulfate system

Most known chemiluminescence (CL) systems are flash-type that generate weak luminescence and decline quickly after dozens of seconds, while the glow-type CL systems have stable emission for an extended period to achieve accurate quantitation. In this work, a long-term CL system based on hydrazine-hydrate (N2H4·H2O) modified carbon quantum dots (N-CQDs) as a luminescent probe, with K2S2O8 and H2O2 as co-reactants, was proposed. The CL emission enhanced by H2O2 increased 18-fold more than that of N-CQDs and K2S2O8 direct reaction, and decayed by 5% of the maximum intensity over 700 s. In the reaction system, K2S2O8 and H2O2 co-reactants can promote each other to continuously generate corresponding radicals (•OH, O2•-, 1O2), which in turn trigger the CL emission of N-CQDs. This phenomenon was identified as the primary cause for the production of persistent CL. In addition, a stable and selective CL sensor based on the N-CQDs-K2S2O8-H2O2 CL enhancing system was developed for ascorbic acid quantitation in the linear range from 0.1 to 10.0 mM with a detection limit of 0.036 mM. The method has been applied to the analysis of tablet samples and holds potential in pharmaceutical analysis field.

Finely-Tuning Chemiluminescent Color of CdTe Nanocrystals and Its Application for Near-Infrared Semi-Automatic Immunoassay

Chemiluminescence (CL), especially commercialized CL immunoassay (CLIA), is normally performed within the eye-visible region of the spectrum by exploiting the electronic-transition-related emission of the molecule luminophore. Herein, dual-stabilizers-capped CdTe nanocrystals (NCs) is employed as a model of nanoparticulated luminophore to finely tune the CL color with superior color purity. Initialized by oxidizing the CdTe NCs with potassium periodate (KIO4), intermediates of the reactive oxygen species (ROS) tend to charge CdTe NCs in both series-connection and parallel-connection routes and dominate the charge-transfer CL of CdTe NCs. The CdTe NCs/KIO4 system can exhibit color-tunable CL with the maximum emission wavelength shifted from 694 nm to 801 nm, and the red-shift span is over 100 nm. Both PL and CL of each of the CdTe NCs are bandgap-engineered; the change in the NCs surface state via CL reaction enables CL of each of the CdTe NCs to be red-shifted for ∼20 nm to PL, while the change in the NCs surface state via labeling CdTe NCs to secondary-antibody (Ab2) enables CL of the CdTe NCs-Ab2 conjugates to be red-shifted for another ∼20 nm to bare CdTe NCs. The CL of CdTe753-Ab2/KIO4 is ∼791 nm, which can perform near-infrared CL immunoassay and semi-automatically determined procalcitonin (PCT) on commercialized in vitro diagnosis (IVD) instruments.

A Screen-Printed Voltammetric Sensor Modified with Electropolymerized Molecularly Imprinted Polymer (eMIP) to Determine Gallic Acid in Non-Alcoholic and Alcoholic Beverages

This paper presents a low-cost disposable sensor for gallic acid (GA) detection in non-alcoholic and alcoholic beverages using a screen-printed cell (SPC) whose working electrode (in graphite) is modified with electrosynthesized molecularly imprinted polypyrrole (eMIP). Our preliminary characterization of the electrochemical process shows that gallic acid (GA) undergoes irreversible oxidation at potentials of about +0.3 V. The peak potential is not affected by the presence of the eMIP film and alcohol percentages (ethanol) up to 20%. The GA determination is based on a differential pulse voltammetry (DPV) analysis leveraging its oxidation peak. The calibration data and the figures of merit of the analytical method (LOD, LOQ, and linear range) are calculated. To validate the feasibility of the sensor's application for the dosing of GA in real matrices, some non-alcoholic and alcoholic beverages are analyzed. The results are then compared with those reported in the literature and with the total polyphenol content determined by the Folin-Ciocalteu method. In all cases, the concentrations of GA align with those previously found in the literature for the beverages examined. Notably, the values are consistently lower than the total polyphenol content, demonstrating the sensor's selectivity in discriminating the target molecule from other polyphenols present.

Alginate based films integrated with nitrogen-functionalized carbon dots and layered clay for active food packaging applications

The applications of alginate derived from seaweed polysaccharide in food packaging are restricted due to their inherent deficient antibacterial, antioxidant and UV barrier properties. In this study, nitrogen-functionalized carbon dots (NCDs) with active functions (0.5-3 %) and layered clay (1 %) with barrier property were introduced to construct alginate based active films via solution casting method. The results showed that the synthesized spherical NCDs had a particle size of 2-3 nm, and the internal structure of NCDs was similar to graphene, with a large number of active groups (-NH2, -OH, etc.) on the surface. Infrared analysis revealed that NCDs could form strong hydrogen bonds with alginate matrix, which slowed down the deterioration of mechanical properties and reduced the surface wettability. With the addition of NCDs, active functions and surface hydrophobicity of the active films were enhanced significantly (P < 0.05). When the amount of NCDs reached 3 %, UV barrier, antioxidant and antibacterial properties of the active films were increased by 50.0 %, 61.1 % and 70.1 %, respectively. The addition of NCDs could enhance the anti-browning ability of alginate based coatings and extend the shelf life of banana significantly. Therefore, a suitable amount of NCDs (1-2 %) and layered clay (1 %) can synergistically improve comprehensive performance of alginate based films and promote their food packaging application used as active films/inner coatings.

N,N-dicarboxymethyl Perylene-diimide-modified CdV2O6 Nanorods for Colorimetric Sensing of H2O2 and Pyrogallol

The peroxidase-like activity of CdV₂O₆ nanorods has been considerably improved by modification with N, N-dicarboxymethyl perylene-diimide (PDI) as a photosensitizer. The peroxidase-like behaviors are evaluated by virtue of the colorless chromogenic substrate 3,3',5,5'-tetramethylbenzidine (TMB), which is fast changed into blue oxTMB in the presence of H₂O₂ in only 90 s. PDI-CdV₂O₆ exhibits high stability at elevated temperatures and PDI-CdV₂O₆ retains more than 70% of its catalytic activity over a wide range of 15 to 60 °C. The catalytic mechanism of PDI-CdV₂O₆ is ascribed to the synergistic interaction between PDI and CdV₂O₆ and the generation of •O₂^- radicals. Based on the enhanced peroxidase-like activity of PDI-CdV₂O₆, a selective colorimetric sensor has been constructed for H₂O₂ and pyrogallol (PG) with detection limits of 36.5 μM and 0.179 μM, respectively. The feasibility of the proposed sensing platform has been validated by detecting H₂O₂ in milk and pyrogallol in tap water.

A low-cost carbon-based electrochemical platform for determining 2,3-dihydroxyphenol: applications in natural water and biodiesel samples

2,3-Dihydroxyphenol (DHP) is a phenolic compound that has been used as an additive in biodiesel to avoid the auto-oxidation of biofuels and also in the production of cosmetic products. However, this substance can be released into the environment during its manufacture, transport, disposal and industrial use and can be harmful to health due to its toxicity, and hence, monitoring its presence in different samples is very important. Therefore, this work describes an electroanalytical study of DHP using different carbon-based pastes prepared to evaluate which one would be more promising to be used as an electrochemical platform for DHP quantification. The materials studied (graphite, carbon black and carbon nanotubes) in this work were characterized by Fourier transform infrared (FTIR) spectroscopy, Raman spectroscopy and the Boehm method. Voltammetric studies showed that pure carbon black presented a higher current density for detecting DHP than the other materials tested (graphite, carbon black + graphite, carbon nanotubes, carbon nanotubes + graphite). In studying the medium's pH, the highest currents occurred in acid media and acetate buffer solutions. After optimizing the experimental parameters, it was possible to obtain a wide range of linear responses from 0.1 to 10 000 μmol L^-1 for DHP and a good limit of detection (LOD) of 0.03 μmol L^-1. The selectivity of the electrode was tested for different species that may be present in samples containing DHP. Finally, the electrode was applied to determine DHP in natural water and biodiesel samples, showing recovery values between 98 and 102%, indicating good accuracy.

Preparation of Sulfur-doped Carbon for Supercapacitor Applications: A Review

Electrochemical capacitors, also known as supercapacitors (SCs), have lately played an important role in energy storage and conversion systems due to their specific characteristics such as high strength, durability, and environmental friendliness. A wide range of materials is used as electrodes for SC applications because the electrochemical efficiency is primarily determined by the electrode materials used. Carbonaceous materials with unique surface, chemical, electrochemical, and electronic characteristics have become attractive for energy storage research, but they cannot meet the rising need for high specific energy and specific power. Besides, heteroatom-doped carbon materials have shown pseudocapacitance characteristics and improved specific energy, specific power, and conductivity. This makes them more adaptable in SC application. Among different heteroatom doping of carbon, S-doped carbon has gained considerable attention in SC applications due to its unpaired electrons and easily polarizable nature. S-doped carbon materials-based SCs have demonstrated enhanced surface wettability, improved conductivity, and induced pseudocapacitance effect, thereby delivering improved specific energy and specific power. Many reports on S-doped carbon for SC applications have been published, but there is no specific Review on the preparation of S-doped carbon for SC applications. This Review focuses on recent developments in the field of SC electrodes made from S-doped carbon materials. Herein, the preparation methods and applications of S-doped carbon for SCs were summarized following a brief discussion of different electrochemical characterization techniques of SCs. Finally, the challenges of S-doped carbon materials and their potential prospects were discussed to give crucial insights into the favorable factors for future innovations of SC electrodes. This Review aims to provide insight for further research on the preparation of S-doped carbon for electrochemical energy storage applications.

Determination of thiourea by terbium (III)/ prulifloxacin sensitized potassium permanganate-sulfite chemiluminescence with quenching method

Based on the thiourea quenching of the chemiluminescence of Tb³⁺/ prulifloxacin (PUFX) sensitized KMnO₄-Na₂SO₃ system, a convenient and rapid chemiluminescence method for the determination of thiourea was proposed. The reaction between KMnO₄ and Na₂SO₃ brought only weak chemiluminescence, but the chemiluminescence increased sharply in the presence of sensitizer Tb³⁺/ PUFX. Addition of thiourea can prevent the reaction between KMnO₄ and Na₂SO₃, thus the chemiluminescence intensity was significantly decreased. Under the optimum conditions, the calibration graphs for thiourea were linear in the range of 1.0 × 10^-7 to 4.0 × 10^-5 mol•L^-1. The limit of detection was 6.4 × 10^-8 mol•L^-1. The method was applied satisfactorily to the determination of thiourea in tap water, lake water and rice noodles and the spiked recoveries were between 104.7 ~ 113.4%. The possible mechanism of sensitization and quenching was also proposed.

Facile synthesis of silver modified zinc oxide nanocomposite: An efficient visible light active nanomaterial for bacterial inhibition and dye degradation

The present study reports the synthesis of silver (Ag) decorated zinc oxide (ZnO) nanocomposite via green synthesis method by using Acacia arabica plant leaves extract as both reducing and capping agent. The results clearly indicate a uniform distribution of Ag nanoparticles (NPs) over ZnO surface. Various analytical and spectroscopic techniques were used for investigating the formation and morphology of as-synthesized Ag/ZnO nanocomposites. Emergence of SPR at 424 and 378 nm confirmed the synthesis of AgNPs and ZnO respectively. The confirmation of elemental composition and crystal structure of prepared nanomaterials (NMs) was carried out via EDX and XRD analysis. Results obtained from HRTEM and SEM analysis indicated small sized spherically shaped NMs. The as-synthesized was checked for its photocatalytic activity towards degradation of MB in the presence as well as absence of light irradiation. Results of degradation study revealed that Ag/ZnO exhibits remarkable photocatalytic activity in the presence of light whereby removing 90% of MB within 80 min. Moreover, the antibacterial activity of synthesized nanocomposite was examined in both visible light and dark conditions. The experiment showed that nanomaterial depicts enhanced antibacterial activity in light in comparison to dark. The results showed that the inhibition diameter of Ag/ZnO nanocomposite in light was found to be 18 (±0.2), 22 (±0.3) against E. coli and S. aureus respectively. The inhibition zone of the said nanomaterial against E. coli and S. aureus in dark was 11 (±0.3), 14 (±0.5) respectively. These results conclude that activity is delivered both in the presence of visible light and dark but efficiency of antibacterial activity is found to be more in visible light in comparison.

A facile green and one-pot synthesis of grape seed-derived carbon quantum dots as a fluorescence probe for Cu(ii) and ascorbic acid

In this study, an on–off–on fluorescence probe for the detection of trace Cu(ii) and ascorbic acid (AA) based on biomass-derived sulfur and nitrogen double heteroatom-doped carbon dots (N,S-CDs) was designed. For the first time, the probe (N,S-CDs) was prepared from grape seeds and thiourea as the precursor. Cu(ii) was added to the carbon point solution, the fluorescence intensity (FL) of N,S-CDs was strongly quenched (switch OFF) and the fluorescence probe turned to “ON” (switch ON) with the addition of AA. Under the optimal conditions, the as-synthesized N,S-CDs had a good detection performance for Cu(ii) and AA assay with the linearity ranges from 150–500 μg mL⁻¹ and 0.1–400 μg mL⁻¹, and the LODs were 0.048 mg L⁻¹ and 0.036 mg L⁻¹, respectively. The as-prepared N,S-CDs exhibited a low cytotoxicity and a good biocompatibility, which show their potential for application in the biological imaging of living cells.

In this study, an on–off–on fluorescence probe for the detection of trace Cu(ii) and ascorbic acid (AA) based on biomass-derived sulfur and nitrogen double heteroatom-doped carbon dots (N,S-CDs) was designed.

A chemiluminescence probe enhanced by cobalt and nitrogen-doped carbon dots for the determination of a nitrosative stress biomarker

A chemiluminometric method is introduced for the determination of the stress biomarker, 3-nitrotyrosine (3-NT) based on the H₂O₂-NaIO₄ reaction enhanced by cobalt and nitrogen-doped carbon dots (Co,N-CDs). In this chemiluminescence (CL) system, the emission proved to be originated from the excited-state Co,N-CDs (λ_max = 504 nm). Comparing the effect of Co,N-CDs with that of some other metal ion-doped CDs and undoped CDs indicated the high efficiency of Co,N-CDs in the CL amplification (about 1980-fold). This was attributed to the fact that Co,N-CDs, in addition to other functions, could act as catalytic center, to accelerate the decomposition of H₂O₂ and to increase the number of hydroxyl radicals. It was found that 3-NT inhibits the action of Co,N-CDs by an electron transfer process, leading to a decline in the CL intensity of the system. Therefore, a new CL sensing platform was introduced for the assay of 3-NT in the range 5.0 to 300 nM with a detection limit of 1.5 nM. The probe was utilized for the analysis of biological samples.

Natural source of carbon dots from part of a plant and its applications: a review

Carbon dots (CDs) are carbon nanoparticles with a size of less than 10 nm, and are synthesized from various sources; they have been of great interest to scientists worldwide due to their unique optical, electrical, and chemical properties. Sources of carbon are inexpensive and can be classified as a renewable natural resources. Many researchers use CDs because of their low toxicity, better water solubility, high biocompatibility, and stable photoluminescence. The simple methods for producing CDs are hydrothermal and use inexpensive equipment, have low energy consumption, simple manipulation, and one-step preparation. Since the discovery of CDs, researchers have used them in various applications such as sensing, bioimaging, drug delivery, and catalysis. In this review, CDs synthesized from natural resources such as samples from herbs, roots, leaves, flowers, and fruit and some applications are described. This review provides a summary of carbon dots that is expected to provide further information for development of new CDs.

A nitrogen doped carbon dots-enhanced peroxynitrous acid chemiluminescence method for 2-naphthol detection

A weak CL emission was initiated by peroxynitrous acid (PA) produced by the interaction of nitrite with hydrogen peroxide in sulphuric acid solution. In the presence of nitrogen doped carbon dots (NCDs), the CL intensity was enhanced significantly. The CL mechanism of the NCDs-PA system was studied using the CL spectrum, FL spectrum and the effect of radical scavengers. The NCDs-PA CL system was developed for the determination of 2-naphthol (2-NAP) based on its inhibition effect. The reduced CL intensity was proportional to the concentration of 2-NAP in the range from 0.3 to 20.0 μM and the detection limit was 48.0 nM. This method had been successfully applied to determine 2-NAP in environmental water samples with recoveries of 99.5-102.8%.

Nanomaterial-enhanced chemiluminescence reactions and their applications

Chemiluminescence (CL) analysis is a trace analytical method that possesses advantages including high sensitivity, wide linear range, easy operation, and simple instruments. With the development of nanotechnology, many nanomaterial (NM)-enhanced CL systems have been established in recent years and applied for the CL detection of metal ions, anions, small molecules, tumor markers, sequence-specific DNA, and RNA. This review summarizes the research progress of the nanomaterial-enhanced CL systems the past five years. These CL reactions include luminol, peroxyoxalate, lucigenin, ultraweak CL reactions, and so on. The CL mechanisms of the nanomaterial-enhanced CL systems are discussed in the first section. Nanomaterials take part in the CL reactions as the catalyst, CL emitter, energy acceptor, and reductant. Their applications are summarized in the second section. Finally, the challenges and opportunities are discussed.

Analysis of methylparaben in cosmetics based on a chemiluminescence H2 O2 -NaIO4 -CNQDs system

In this article, a simple, effective chemiluminescence (CL) method for the detection of methylparaben (MP) in cosmetic samples was developed based on an IO₄ ^- -H₂ O₂ -carbon nitrogen quantum dots (CNQDs) system without a separation process. The results indicated that the redox reaction between periodate and hydrogen peroxide released hydroxide radicals and superoxide radical anions in the presence of bicarbonate. These two radicals were responsible for the formation of excited luminophor CNQD* with a maximum wavelength at 480 nm. Due to the competitive reaction with hydroxide radicals, CL intensity was markedly diminished in the presence of MP. The relative standard deviation in the intraday assay was below 5.5% (n = 9), and the detection limit was as low as 0.50 μmol/L. The proposed method allowed for the successful, selective determination of MP in cosmetics.

Periodate activation with manganese oxides for sulfanilamide degradation

This study presents a novel periodate oxidation system mediated by manganese oxides for the rapid removal of aqueous contaminants. The catalytic activation of periodate on manganese oxides was demonstrated as an efficient advanced oxidation system for degradation of sulfanilamide. The reactivity of manganese oxides with different Mn valence followed the order of MnO₂>Mn₃O₄>Mn₂O₃, all of which showed extraordinary reusability during repeated activation of periodate. Sulfanilamide was rapidly degraded along with stoichiometric transformation of IO₄^- to IO₃^-, and both processes exhibited good linear correlations with the dosage of manganese oxides. While the degradation of sulfanilamide in the MnO₂/IO₄^- system was accelerated at lower solution pH, it was only slightly affected by ionic strength, water anions and humic acid. In contrast to the homogeneous system of Mn²⁺/IO₄^-, sulfanilamide degradation was not influenced in oxic and anoxic environment. It was evidenced by quenching studies and EPR tests that both singlet oxygen (¹O₂) and iodate radicals (IO₃^•) were generated when the metastable Mn(IV)-O-IO₃ interacted with sulfanilamide. The XPS spectra of Mn 2p and O 1s before and after reactions indicated that the catalytic activation of periodate on MnO₂ was not in company with the redox cycling of Mn(IV) species.

Sulfur and nitrogen co-doped graphene quantum dot-assisted chemiluminescence for sensitive detection of tryptophan and mercury (II)

A simple one-step thermal treatment to prepare strong fluorescent sulfur and nitrogen co-doped graphene quantum dots (SN-GQD) using citric acid and l-cysteine as precursors was developed. The ultra-weak chemiluminescence (CL) from the reaction of hydrogen peroxide (H₂ O₂ ) and periodate (IO₄ ^- ) was significantly enhanced by SN-GQD in acidic medium. The enhanced CL was induced by excited-state SN-GQD (SN-GQD*), which was produced from the transfer energy of (O₂ )₂ * and ¹ O₂ to SN-GQD and recombination of oxidant-injected holes and electrons in SN-GQD. In the presence of tryptophan (Trp), the CL intensity of the SN-GQD-H₂ O₂ -KIO₄ system was greatly diminished. This finding was used to design a novel method for determination of Trp in the linear range 0.6-20.0 μM, with a limit of detection (LOD) of 58.0 nM. Furthermore, Hg²⁺ was detectable in the range 0.1-9.0 μM with a LOD of 64.0 nM, based on its marked enhancement of the SN-GQD-H₂ O₂ -KIO₄ CL system. The proposed method was successfully applied to detect Trp in milk and human plasma samples and Hg²⁺ in drinking water samples, with recoveries in the range 95.7-107.0%.

One-pot synthesis of luminol–gallium nanoassemblies and their peroxidase-mimetic activity for colorimetric detection of pyrophosphate

Luminol–Ga nanoassemblies exhibit peroxidase-mimetic activity. Colorimetric detection of PPi is developed owing to the formation of a complex between PPi and Ga³⁺.

Radical-Triggered Chemiluminescence of Phenanthroline Derivatives: An Insight into Radical-Aromatic Interaction

The hitherto unknown influence of 1,10-phenonthroline (1,10-phen) and its derivatives on the weak chemiluminescence (CL) of periodate-peroxide has been investigated, and a novel method for CL catalysis is described. Herein, we have deconvoluted the variation in CL intensity arising from the addition of various derivatives of 1,10-phen. Interestingly, similar derivatives of 1,10-phen show interesting differences in their reactivity toward CL. Electron-withdrawing substituents on 1,10-phen boosted the CL signals, indicating a negative charge buildup on 1,10-phen in the rate-determining step. The 1,10-phen derivatives having substitution at the C⁵=C⁶ position resulted in no CL signals due to the blockage of the reactive site. Mechanistic investigations are interpreted in terms of free radical (H₂O₂ reaction), followed by the oxygen atom transfer via an electrophilic attack of IO₄ ^- (IO₄ ^- reaction) on 1,10-phen resulting in dioxetane with enhanced CL emission. Additionally, the relationship between electronic structures and photophysical properties was investigated using density functional theory. Our results are expected to open up promising application of 1,10-phen as a molecular catalyst, providing a new strategy for metal-free catalytic CL enhancement reaction. We believe that this would foster in gleaning more detailed information on the nature of these reactions, thereby leading to a deeper understanding of the CL mechanism.

N-doped carbon dots/H2O2 chemiluminescence system for selective detection of Fe2+ ion in environmental samples

The nitrogen doped carbon dots (N-CDs) produces strong chemiluminescence (CL)-emission due to hydroxyl radical (^•OH) induced electron-hole transition in N-CDs. The Fe²⁺ has the ability to generate ^•OH from available hydrogen peroxide (H₂O₂). Therefore, a pre-mixed N-CDs/H₂O₂ solution was utilized for selective quantification of Fe²⁺ in solution via CL-emission. A linear increase in the CL-emission intensity was observed within increase in Fe²⁺ concentration. The N-CDs/H₂O₂ system enabled the detection of Fe²⁺ up to lower concentration of 0.2 × 10^-9 M with a linear dynamic range of 1.0 × 10^-9-1.0 × 10^-6 M. Significantly, no CL-emission was observed when other divalent cations, Al³⁺, Fe³⁺, or Cr³⁺ were injected to this system. Moreover, no interference was observed when a mixed solution of Fe²⁺ and other cations were introduced to N-CDs/H₂O₂. The practical evaluation of N-CDs/H₂O₂ system was demonstrated for detection of Fe²⁺ in tap, lotus pond, and canal water samples. The easy detection, high sensitivity, and selectivity make this method a significant tool for analysis of Fe²⁺ in solution.

Redox cycling of iron by carbon dot enhanced chemiluminescence: mechanism of electron-hole induction in carbon dot

The chemiluminescence (CL) of the Fenton system with nitrogen doped carbon dots (N-CDs) was significantly enhanced. The introduction of N-CDs improved the utilization of H₂O₂ and drastically enhanced the generation of ˙OH, which resulted in enhanced CL emission of the Fenton system through energy and electron transfer processes. The oxidation of N-CDs by ˙OH led to rapid incorporation of oxygen into N-CDs. The mechanism relied on the production of ^•OH radicals through the Fenton reaction and clearly indicated the important role of peroxide-induced redox cycling of Fe²⁺ ⇔ Fe³⁺ in the presence of N-CDs. The CL intensity of the system containing Fe²⁺ was higher than that containing Fe³⁺ because the rate of the Fe³⁺ reaction was much slower than that of the Fe²⁺ reaction. The CL signal remained constant after some time due to redox cycling, which established equilibrium, irrespective of the form of iron. This study provides a feasible approach to greatly enhance the weak CL of the Fenton system with the introduction of environmentally friendly N-CDs, and initiates an inspiring research in the domain of catalysis, CL and the mechanism of the Fenton system, which will be helpful in various applied research areas.

A chemiluminescence resonance energy transfer for the determination of indolyl acetic acid using luminescent nitrogen-doped carbon dots as acceptors

A CRET method was fabricated for the determination of IAA using Ce(iv)–Na₂SO₃ as the donor and N-CDs as the acceptor.

A label-free, versatile and low-background chemiluminescence aptasensing strategy based on gold nanocluster catalysis combined with the separation of magnetic beads

A label-free, versatile and low-background chemiluminescence sensing strategy based on gold nanocluster catalysis combined with magnetic separation was developed.

Novel imidazole fluorescent poly(ionic liquid) nanoparticles for selective and sensitive determination of pyrogallol

This paper reports novel imidazole fluorescent poly(ionic liquid) nanoparticles (FPILNs) of poly(1-[(4-methyphenyl)methyl]-3-vinyl-imidazolium bromide (poly([MVI]Br) for selective and sensitive determination of pyrogallol. An imidazole ionic liquid of 1-[(4-methyphenyl)methyl]-3-vinyl-imidazolium bromide ([MVI]Br) was synthesized and used as the only monomer to obtain poly([MVI]Br) possessing phenyl fluorophores using a radical polymerization technique. The obtained poly([MVI]Br) can form nanoparticles in water. Scanning electron microscopy and dynamic light scattering results revealed majority of poly([MVI]Br) FPILNs with diameters ranging from 40 to 400nm. Although [MVI]Br showed weak fluorescence intensity, poly([MVI]Br) FPILNs exhibited strong fluorescence intensity with a quantum yield of 0.192, which is attributed to the presence of significant number of phenyl fluorophores and rigid construction. The selective and sensitive determination of pyrogallol was achieved through fluorescence quenching of poly([MVI]Br) FPILNs, and the quenching was attributed to the oxidation of poly([MVI]Br) FPILNs by O₂˙¯ produced by pyrogallol autoxidation. The poly([MVI]Br) FPILNs-based sensor demonstrated a good linear relationship between the extent of fluorescence quenching and the concentration of pyrogallol in a range of 0.05 - 10.0μM, achieving a detection limit of 0.01μM. Furthermore, the poly([MVI]Br) FPILNs-based assay detected pyrogallol in environmental water samples, suggesting its potential to be applied for practical purposes.

Recent advances in chemiluminescence based on carbonaceous dots

Herein, a broad overview concerning the most recent progress of carbon dots (CDs) in chemiluminescence (CL) as well as the mechanisms and applications are presented. CDs have excellent optical and electronic properties and are very important advancement in the fast growing domain of nanotechnology. CDs enhance the ultraweak CL of different systems. The mechanisms and applications of these enhanced CL reactions are discussed. It is worthy to note that CDs participate in CL reactions as catalysts, energy acceptors or are directly involved in redox reactions with radicals in CL systems. Sometimes, these processes taking place simultaneously to enhance CL intensity. In this report, recent advances in CD based CL are comprehensively summarized and their applications in detection of various reagents and biological molecules are reviewed. The challenges and future prospects of this field are also discussed.