Ultrasensitive near-infrared electrochemiluminescence biosensor derived from Eu-MOF with antenna effect and high efficiency catalysis of specific CoS2 hollow triple shelled nanoboxes for procalcitonin

Facile synthesis of sulfur quantum dots with red light emission: Implications for electrochemiluminescence analysis application

Sulfur quantum dots (SQDs) have been reported as a potential candidate due to their low toxicity and high luminescent performance. Here, SQDs with red light fluorescence (FL) emission were synthesized by a one-step hydrothermal method using Na2CO3 as an etching agent, using sublimed sulfur powder as a sulfur source, and using bovine serum albumin (BSA) as a stabilizer. The choice of etching agent (NaOH or Na2CO3) realized the tuning of SQDs' FL emission with blue and red light. The synthesized SQDs showed good FL stability and high FL efficiency, with a quantum yield of 1.03 % in an aqueous solution at 575 nm. In addition, stable and efficient electrochemiluminescence (ECL) emission was achieved by employing SQDs as ECL emitters with K2S2O8 as the co-reactant. The resorcinol (RS) can enhance the ECL intensity of the SQDs-K2S2O8 system, and the ECL intensity had a good linear relationship with the concentration of RS in a range from 2.5 nM to 25 nM with a detection limit of 0.61 nM. This work provides an emerging red-light luminescent SQDs, which would open up a way for the development of new types of luminophor in FL or ECL analysis. It also provides convenience for bio-labeling of live cells, in vivo imaging and provide new materials for photoelectric devices.

Dual-ligand Eu-MOF/CuS@Au Heterostructure Array-based ECL Sensor for MiRNA-128 Detection in Glioblastoma Tissues

In this work, the dual-ligand lanthanide metal-organic framework (MOF)-based electrochemiluminescence (ECL) sensor was constructed for the detection of miRNA-128 in glioblastoma (GBM) diagnosis. The luminescent Eu-MOF (EuBBN) was synthesized with terephthalic acid (BDC) and 2-amino terephthalic acid (BDC-NH2) as dual-ligand. Due to the antenna effect, EuBBN with conjugated-π structure exhibited strong luminescent signal and high quantum efficiency, which can be employed as ECL nanoprobe. Furthermore, the novel plasmonic CuS@Au heterostructure array has been prepared. The localized surface plasmon resonance coupling effect of the CuS@Au heterostructure array can amplify the ECL signal of EuBBN significantly. The EuBBN/CuS@Au heterostructure array-based sensing system has been prepared for the detection of miRNA-128 with a wide linear range from 1 fM to 1 nM and a detection limit of 0.24 fM. Finally, miRNA-128 in the clinic GBM tissue sample has been analysis for the distinguish of tumor grade successfully. The results demonstrated that the dual-ligand MOF/CuS@Au heterostructure array-based ECL sensor can provide important support for the development of GBM diagnosis.

Photoelectrochemical signal polarity transition mediated by quercetin for the detection of neuron-specific enolase

A photoelectrochemical (PEC) biosensor with a wide linear detection range was developed for the sensitive detection of neuron-specific enolase (NSE), which was achieved by applying a photocurrent polarity transition strategy mediated by quercetin. The coupling reaction between Cr(VI) and quercetin drives the signal polarity from anodic to cathodic. When only quercetin is present in the test solution, photogenerated electrons are transferred to the electrode to generate anodic photocurrent. However, in the presence of the target, the signal probe released Cr(VI), which interacted with quercetin, and the electron transfer direction was changed to achieve signal polarity conversion. Meanwhile, protoporphyrin-sensitized Bi:SrTiO3 nanocubes were used as matrix photoactive materials to provide basic photocurrent. The doping of Bi element would adjust the bandgap of SrTiO3, and the organic-inorganic composite material exhibits good photostability and chemical stability that can maintain stable photoelectric properties over a long period of time. Such a novel signal polarity transition strategy greatly broadened the sensor detection to the range of 0.00007-170 ng mL-1 and obtained a relatively low detection limit (25 fg mL-1), which greatly improved the detection sensitivity and accuracy of the biosensor.

A magnetic plasma Fe3O4@Cu@Cu2O photoelectrochemical sensor for the detection of fumonisin B1

Fumonisin B1 (FB1) is a mycotoxin, a water-soluble metabolite produced by Fusarium cepacia, which mainly contaminates grain and its products and is acutely toxic and potentially carcinogenic to certain domestic animals. In this work, plasma nanocomposites of Fe3O4@Cu@Cu2O with magnetic and optoelectronic properties were synthesized as a sensing platform. On one hand, the surface plasmon resonance (SPR) of metallic Cu accelerates the electron transfer rate. On the other hand, plasma-induced resonance energy transfer of metals and semiconductors can improve the utilization efficiency of light energy. A split photoelectrochemical (PEC) sensor based on Fe3O4@Cu@Cu2O was proposed for the detection of FB1. The sensor has a wide linear range of 1.0-10 000 pg mL-1 and a low detection limit of 0.28 pg mL-1 (LOD, S/N = 3), which can realize the specific detection of FB1 in real samples.

Portable, intelligent MIECL sensing platform for ciprofloxacin detection using a fast convolutional neural networks-assisted Tb@Lu2O3 nanoemitter

Environmental pollution caused by ciprofloxacin is a major problem of global public health. A machine learning-assisted portable smartphone-based visualized molecularly imprinted electrochemiluminescence (MIECL) sensor was developed for the highly selective and sensitive detection of ciprofloxacin (CFX) in food. To boost the efficiency of electrochemiluminescence (ECL), oxygen vacancies (OVs) enrichment was introduced into the flower-like Tb@Lu2O3 nanoemitter. With the specific recognition reaction between MIP as capture probes and CFX as detection target, the ECL signal significantly decreased. According to, CFX analysis was determined by traditional ECL analyzer detector in the concentration range from 5 × 10-4 to 5 × 102 μmol L-1 with the detection limit (LOD) of 0.095 nmol L-1 (S/N = 3). Analysis of luminescence images using fast electrochemiluminescence judgment network (FEJ-Net) models, achieving portable and intelligent quick analysis of CFX. The proposed MIECL sensor was used for CFX analysis in real meat samples and satisfactory results, as well as efficient selectivity and good stability.

Double-enhanced sandwich electrochemiluminescence aptasensor based on g-C3N4-Au-luminol nanocomposites and ZnCuS nanosheets for highly sensitive detection of mucin 1

The traditional luminol electrochemiluminescence (ECL) sensing suffers from low signal response and instability issues. Here, an Au/ZnCuS double-enhanced g-C3N4-supported luminol ECL aptasensor is constructed for the sensitive detection of human mucin 1 (MUC1). In this platform, g-C3N4 of a large specific surface area is beneficial to load more luminol illuminants. Au nanoparticles promote the decomposition of H2O2 coreactants to generate more reactive oxygen (•OH and O2•-) intermediates, while ZnCuS can immobilize the aptamer and simultaneously catalyze H2O2 decomposition, realizing the double-wing signal amplification. Under optimal conditions, this sensor shows a good detection capability within 1.0 × 10-4-1.0 × 103 ng mL-1 and a low detection limit of 5.0 × 10-5 ng mL-1, as well as ideal stability, selectivity, and reproducibility. This double-enhanced aptasensor highlights a new signal-enhancement approach for early biomarker detection.

Dendritic quinary PtRhMoCoFe high-entropy alloy as a robust immunosensing nanoplatform for ultrasensitive detection of biomarker

Recently, high-entropy alloys have superior physicochemical properties as compared to conventional alloys for their glamorous "cocktail effect". Nevertheless, they are scarcely applied to electrochemical immunoassays until now. Herein, uniform PtRhMoCoFe high-entropy alloyed nanodendrites (HEANDs) were synthesized by a wet-chemical co-reduction method, where glucose and oleylamine behaved as the co-reducing agents. Then, a series of characterizations were conducted to illustrate the synergistic effect among multiple metals and fascinating structural characteristics of PtRhMoCoFe HEANDs. The obtained high-entropy alloy was adopted to build a electrochemical label-free biosensor for ultrasensitive bioassay of biomarker cTnI. In the optimized analytical system, the resultant sensor exhibited a dynamic linear range of 0.0001-200 ng mL-1 and a low detection limit of 0.0095 pg mL-1 (S/N = 3). Eventually, this sensing platform was further explored in serum samples with satisfied recovery (102.0 %). This research renders some constructive insights for synthesis of high-entropy alloys and their expanded applications in bioassays and bio-devices.

Near-infrared electrochemiluminescence biosensors facilitated by thermally activated delayed fluorescence (TADF) emitters for ctDNA analysis

The near-infrared electrochemiluminescence technique (NIR ECL) has gained significant attention as a powerful analytical tool in biomedicine and clinical diagnosis due to its inherent advantages. In this work, we successfully synthesized a novel NIR ECL emitter of TPA-DCPP nanoparticles (NPs) with a D-π-A-π-D configuration. By utilizing the thermally activated delayed fluorescence (TADF) property, we achieved enhanced electrochemiluminescence (ECL) emission through complete exciton harvesting for radiative decay. Specifically, when BDEA was used as a co-reactant, the TPA-DCPP NPs exhibited strong bandgap ECL emission. Additionally, they demonstrated an exceptionally higher ECL efficiency compared to conventional near-infrared fluorescence organic nanomaterials (BSeT-BT NPs). By integrating the efficient anodic ECL performance of TPA-DCPP NPs with Exo III-assisted polymerase enzyme reaction cascade amplification, a highly efficient ECL resonance energy transfer (ECL-RET) platform was developed for ultrasensitive detection of circulating tumor DNA (ctDNA). The established biosensor demonstrated an exceptional linear dynamic range and achieved attomolar-level detection limit. This study highlights the immense potential of TADF emitters in enhancing ECL efficiency and extends the emission wavelength of organic nanomaterials to the NIR region, thereby expanding their applications in biological analysis.

A Co-Reactive Immunosensor Based on Ti3C2Tx MXene@TiO2-MoS2 Hybrids Promoting luminol@Au@Ni-Co NCs Electrochemiluminescence for CYFRA 21-1 Detection

The construction of assays is capable of accurately detecting cytokeratin-19 (CYFRA 21-1), which is critical for the rapid diagnosis of nonsmall cell lung cancer. In this work, a novel electrochemiluminescence (ECL) immunosensor based on the co-reaction promotion of luminol@Au@Ni-Co nanocages (NCs) as ECL probe by Ti3C2Tx MXene@TiO2-MoS2 hybrids as co-reaction accelerator was proposed to detect CYFRA 21-1. Ni-Co NCs, as a derivative of Prussian blue analogs, can be loaded with large quantities of Au NPs, luminol, and CYFRA 21-1 secondary antibodies due to their high specific surface area. To further improve the sensitivity of the developed ECL immunosensor, Ti3C2Tx MXene@TiO2-MoS2 hybrids were prepared by in situ growth of TiO2 nanosheets on highly conductive Ti3C2Tx MXene, and MoS2 was homogeneously grown on Ti3C2Tx MXene@TiO2 surfaces by the hydrothermal method. Ti3C2Tx MXene@TiO2-MoS2 hybrids possess excellent catalytic performance on the electro-redox of H2O2 generating more O2·- and obtaining optimal ECL intensity of the luminol/H2O2 system. Under the appropriate experimental conditions, the quantitative detection range of CYFRA 21-1 was from 0.1 pg mL-1 to 100 ng mL-1, and the limit of detection (LOD) was 0.046 pg mL-1. The present sensor has a lower LOD with a wider linear range, which provides a new analytical assay for the early diagnosis of small-cell-type lung cancer labels.

Sensitive electrochemiluminescence immunosensor based on a novel luminescent europium metal-organic framework and antenna effect for detecting pro-gastrin-releasing peptide

Sensitive detection of pro-gastrin-releasing peptide (Pro-GRP) is crucial because it is a highly sensitive and specific tumor marker for small cell lung cancer. Herein, we synthesized an efficient luminescent europium metal-organic framework and developed a sandwich ECL immunosensor for the sensitive detection of Pro-GRP, which used Eu3+ as the central ion and 2,4,6-tri (4-carboxyphenyl)-1,3,5-triazine (H3TATB) as the organic ligand. H3TATB acted as a strong absorbing reagent and transferred its energy to Eu3+ via the antenna effect to enhance the ECL response signal of Eu3+. As per calculations, the ECL efficiency of Eu-TATB, which was a promising ECL luminophore, was up to 130 %. The Cu2O cube worked as a substrate to assist the electron transfer and was used as a co-reaction accelerator to catalyze S2O82- to produce more SO4•- and then enhance the ECL intensity of Eu-TATB. Under optimal experimental conditions, the ECL immunosensor had a linear range of 5 fg mL-1-50 ng mL-1 for detecting Pro-GRP with a detection limit of 1.6 fg mL-1; moreover, it demonstrated excellent stability and specificity and has been successfully applied for detecting Pro-GRP in the human serum.

A dual-mode biosensor based on silica inverse opal photonic crystals modulated electrochemiluminescence and dye displacement colorimetry for the sensitive detection of synthetic cathinone in water environment

To address the challenges posed by signal capacity limitations and the reliance of sensing methods on single analytical information, this study developed an electrochemiluminescence (ECL) and colorimetric dual-mode sensing platform for the precise detection of 4-chloroethcathinone (4-CEC) in water environments. Firstly, the accurate alignment of the reflection wavelength of appropriately sized silica inverse opal photonic crystals (SIOPCs) with the ECL emission wavelength of luminescent metal-organic frameworks (PCN-224) has been achieved via diameter modulation. This innovative design, which cleverly utilized the band-edge effect, improved the luminous intensity of the ECL sensor, leading to a significant boost in analytical performance. Secondly, the establishment of a colorimetric detection method for confirming the presence of 4-CEC in samples through visual observation of color changes was achieved by employing an aptamer-based dye displacement reaction, utilizing differential binding affinities between the aptamer and both the sulforhodamine B (SRB) and 4-CEC. Under the optimal experimental conditions, the dual-mode sensor demonstrated ECL detection of limits (LOD) of 2.6 × 10-13 g/L and colorimetric LOD of 6.5 ng/L for 4-CEC. These findings highlighted the tremendous potential of developing streamlined and efficient dual-signal readout platforms using ECL aptamer sensors for the precise determination of other Synthetic cathinones (SCs) in water environments.

Facile synthesis of dual-ligand europium-metal organic gels for ratiometric electrochemiluminescence detecting I27L gene

Metal organic gels (MOGs) are a new kind of intelligent soft materials with excellent luminescence properties. However, MOGs with dual electrochemiluminescence (ECL) properties have not been reported. In this study, using Eu3+ as metal node, 4'-(4-carboxyphenyl)-2,2':6',2″-terpyridine (Hcptpy) and Luminol as organic ligands, a novel dual-ligand Europium-organic gels (Eu-L-H MOGs) were prepared by simple mixing at room temperature. On the one hand, Eu-L-H MOGs could exhibit strong and stable anodic ECL signals in the phosphate buffered saline (PBS) without the addition of co-reactants, which came from the blue emission of Luminol. On the other hand, using K2S2O8 as a cathodic co-reactant, Eu-L-H MOGs produced cathodic signals, which were derived from the red emission of Eu sensitized by Hcptpy through the antenna effect. Based on the independent dual ECL signals of Eu-L-H MOGs, we selected Alexa Flour 430 as the receptor and anodic ECL emission of Eu-L-H MOGs as the donor to construct the ECL resonance energy transfer (ECL-RET) ratio biosensor, which utilized exonuclease III assisted DNA cycle amplification to achieve ultrasensitive detection of the I27L gene. The detection linearity of I27L ranged from 1 fM to 10 nM, with a detection limit as low as 284 aM. This study developed a straightforward technique for obtaining a single luminescent material with dual signals, and further broadened the analytical application of MOGs in the realm of ECL.

Nanobiosensors for procalcitonin (PCT) analysis

BACKGROUND

Procalcitonin (PCT) is a critical biomarker that is released in response to bacterial infections and can be used to differentiate the pathogenesis of the infectious process.

OBJECTIVE

In this article, we provide an overview of recent advances in PCT biosensors, highlighting different approaches for biosensor construction, different immobilization methods, advantages and roles of different matrices used, analytical performance, and PCT biosensor construction. Also, we will explain PCT biosensors sensible limits of detection (LOD), linearity, and other analytical characteristics. Future prospects for the development of better PCT biosensor systems are also discussed.

METHODS

Traditional methods such as capillary electrophoresis, high-performance liquid chromatography, and mass spectrometry are effective in analyzing PCT in the medical field, but they are complicated, time-consuming sample preparation, and require expensive equipment and skilled personnel.

RESULTS

In the past decades, PCT biosensors have emerged as simple, fast, and sensitive tools for PCT analysis in various fields, especially medical fields.

CONCLUSION

These biosensors have the potential to accompany or replace traditional analytical methods by simplifying or reducing sample preparation and making field testing easier and faster, while significantly reducing the cost per analysis.

Double-Amplified Electrochemiluminescence Immunoassay Sensor for Highly Sensitive Detection of CA19-9 Using a Ternary Semiconductor CdSSe

In this paper, an electrochemiluminescence (ECL) immunosensor for ultrasensitive detection of CA19-9 was constructed using ternary compound CdSSe nanoparticles as ECL emitter. The immunosensor employs Cu2S and gold-doped diindium trioxide (Au-In2O3) nanocubes as coreaction accelerators to achieve a double-amplification strategy. In general, a hexagonal maple leaf-shaped Cu2S with a large surface area was selected as the template, and the in situ growth of CdSSe on its surface was achieved using a hydrothermal method. The presence of Cu2S not only inhibited the aggregation of CdSSe nanoparticles to reduce their surface energy but also acted as an ECL cathode coreaction promoter, facilitating the generation of SO4•-. Consequently, the ECL intensity of CdSSe was significantly enhanced, and the reduction potential was significantly lower. In addition, the template method was employed to synthesize Au-In2O3 nanocubes, which offers the advantage of directly connecting materials with antibodies, resulting in a more stable construction of the immunosensor. Furthermore, In2O3 serves as a coreaction promoter, enabling the amplification strategy for ECL intensity of CdSSe, thus contributing to the enhanced sensitivity and performance of the immunosensor. The constructed immunosensor exhibited a wide linear range (100 μU mL-1 to 100 U mL-1) and a low detection limit of 80 μU mL-1, demonstrating its high potential and practical value for sensitive detection of CA19-9.

Functionalized nanomaterials-based electrochemiluminescent biosensors and their application in cancer biomarkers detection

To detect a range of trace biomarkers associated with human diseases, researchers have been focusing on developing biosensors that possess high sensitivity and specificity. Electrochemiluminescence (ECL) biosensors have emerged as a prominent research tool in recent years, owing to their potential superiority in low background signal, high sensitivity, straightforward instrumentation, and ease of operation. Functional nanomaterials (FNMs) exhibit distinct advantages in optimizing electrical conductivity, increasing reaction rate, and expanding specific surface area due to their small size effect, quantum size effect, and surface and interface effects, which can significantly improve the stability, reproducibility, and sensitivity of the biosensors. Thereby, various nanomaterials (NMs) with excellent properties have been developed to construct efficient ECL biosensors. This review provides a detailed summary and discussion of FNMs-based ECL biosensors and their applications in cancer biomarkers detection.

An electrochemiluminescence sensor based on the CNTs and CdSe@ZnSe for determination of melamine in milk samples

In this work, a novel electrochemiluminescence (ECL) sensor based on the CdSe@ZnSe and CNTs was constructed for the detection of melamine. CdSe@ZnSe acted as the co-reaction promoter for the enhancement of Ru(bpy)32+/tri-n-propylamine (TPrA) system and CNTs acted as carriers to immobilize more CdSe@ZnSe. The initial ECL signal significantly amplified due to the synergistic effect of CNTs and CdSe@ZnSe. The ECL signal decreased with the addition of melamine, and the change value of ECL intensity (ΔI) was linearly related to the logarithm of melamine concentration. The constructed ECL sensor was able to detect melamine in the range of 1.0 × 10-11 - 1.0 × 10-7 M, and the detection limit was 3.3 × 10-12 M (S/N = 3). It can be used to detect melamine in milk samples.

Porphyrin-based metal-organic frameworks enhanced electrochemiluminescence (ECL) by overcoming aggregation-caused quenching: A new ECL emitter for the detection of trenbolone

The development of new electrochemiluminescence (ECL) luminophores has become a hot research topic in the field of ECL. Metal-organic frameworks (MOFs) are widely used in ECL sensors due to their excellent ECL performance, high porosity, and abundant surface functional groups. In the work, we developed a cerium-based organic backbone as an ECL luminophor using 5,10,15,20-tetrakis(4-carboxyphenyl)-porphyrin (TCPP) as organic ligand for the detection of trenbolone (TRE). Importantly, the Ce-MOFs can effectively prevent the self-aggregation and self-quenching of TCPP, so that the ECL signal is amplified. To further improve the conductivity and antigen loading capacity of the Ce-MOFs, platinum nanosheets (Pt NPs) were modified at its surface (Pt NPs@MOFs). The Au-ZnO with good biocompatibility is used as the substrate material to load that antibody through the Au-NH2. Based on the above strategy, we constructed a competitive immunosensor to achieve a highly sensitive detection of TRE. Under suitable circumstances, it was discovered that the ECL sensor had a linear relationship with the logarithm of the TRE concentration, with a limit of detection (LOD) of 3.61 fg/mL (S/N = 3). This work provides direction for the application of organic luminescent porphyrins and their derivatives in ECL sensors.

Antenna effect of perylene-sensitized up-conversion luminescent material amplifies the signal of electrochemiluminescence biosensor platform for the ultra-sensitive detection of enrofloxacin

Recently, up-conversion luminescent (UCL) materials have caught extensive sight on account of their excellent biocompatibility and weak automatic fluorescence background, but the low optical signal makes researchers shy away. Organic dye-sensitized UCL materials can improve the low optical signal drawback of UCL and rejuvenate it with adjustable optical properties and unique antenna effects. In this work, an efficient, simple and selective electrochemiluminescence (ECL) sensing platform was developed for determination of enrofloxacin (ENR). 3,4,9,10-perylene tetracarboxylic acid (PTCA) was successfully used as an "antenna" to improve the ECL performance of the UCL nanoparticles (PEI-NaYF4: Yb, Er) due to its appropriate excitation spectrum position and superior electron transfer rate. The specific recognition function of the aptamer enabled the sensor to eliminate the interference from conspecific impurity. In the presence of ENR, the specific combination of ENR with aptamer made the aptamer fall from surface of the electrode, thus we could see a considerable enhancement of signal. Under the most favourable conditions, the aptasensor based on antenna effect displayed a wide detection range (1.0 × 10-14∼1.0 × 10-6 M), low limit of detection (LOD = 3.0 × 10-15 M) and receivable recoveries (96.0%-102.4%) during water samples analysis. At this point, antenna effect provides a powerful strategy to expand the application of UCL in the field of ECL biosensing.

A novel micron europium cluster coordination polymer as a strong electrochemiluminescent emitter for accurate and sensitive detection of tetracycline

In this work, a self-luminescent micron europium cluster coordination polymer (Eu-CCP) cathode electrochemiluminescence (ECL) emitter is first reported. The mass percentage of Eu in Eu-CCP is 50.1%, indicating that Eu-CCP has a high-nucleation luminescence center. In addition, our Eu-CCP possesses a stable and efficient ECL red emission performance, and the intensity is approximately 6.5-fold higher than that of the traditional tris(2,2'-bipyridyl)ruthenium(II) dichloride. The enhancement of Eu-CCP luminescence in our system is due to the following reasons: (1) the mixed ligand and high nuclear europium luminescent center can cooperate to improve the quenching effect induced by water or hydroxyl groups; and (2) external coreaction accelerator and coreactant enhancement. We also investigate the application of Eu-CCP in ECL sensors by sensitive detection of tetracycline (TC). The low detection limit (73.5 fmol·L^-1), high selectivity, good stability and satisfactory recoveries indicate that our ECL strategy can be used to detect TC accurately and sensitively.

Atomically Fe-anchored MOF-on-MOF nanozyme with differential signal amplification for ultrasensitive cathodic electrochemiluminescence immunoassay

The successful application of electrochemiluminescence (ECL) in immunoassays for clinical diagnosis requires stable electrodes and high-efficient ECL signal amplification strategies. Herein, the authors discovered a new class of atomically dispersed peroxidase-like nanozymes with multiple active sites (CoNi-MOF@PCN-224/Fe), which significantly improved the catalytic performance and uncovered the underlying mechanism. Experimental studies and theoretical calculation results revealed that the nanozyme introduced a Fenton-like reaction into the catalytic system and the crucial synergistic effects of definite active moieties endow CoNi-MOF@PCN-224/Fe strong electron-withdrawing effect and low thermodynamic activation energy toward H2O2. Benefiting from the high peroxidase-like activity of the hybrid system, the resultant ECL electrode exhibited superior catalytic activity in the luminol-H2O2 system and resulted in an ≈17-fold increase in the ECL intensity. In addition, plasmonic Ag/Au core-satellite nanocubes (Ag/AuNCs) were designed as high-efficient co-reactant quenchers to improve the performance of the ECL immunoassay. On the basis of the differential signal amplification strategy (DSAS) proposed, the immunoassay displayed superior detection ability, with a low limit of detection (LOD) of 0.13 pg mL-1 for prostate-specific antigen (PSA). The designed atomically anchored MOF-on-MOF nanozyme and DSAS strategy provides more possibilities for the ultrasensitive detection of disease markers in clinical diagnosis.

Electrochemiluminescence Immunosensors Based on ECL-RET Triggering between Mn SANE/PEI-Luminol and PtCu/h-MPF for Ultrasensitive Detection of CEA

In this paper, a novel donor-acceptor pair was creatively proposed based on the principle of electrochemiluminescence resonance energy transfer (ECL-RET): luminol immobilized on polyethyleneimine (PEI)-functionalized manganese-based single-atom nanozymes (Mn SANE/PEI-luminol, donor) and a PtCu-grafted hollow metal polydopamine framework (PtCu/h-MPF, acceptor). A quenched ECL immunosensor was constructed for the ultrasensitive analysis of carcinoembryonic antigen (CEA). Mn SANE, as an efficient novel coreaction accelerator with the outstanding performance of significantly activating H₂O₂ to produce large amounts of ROS, was further modified by the coreactant PEI, which efficiently immobilized luminol to form a self-enhanced emitter. As a result, the electron transport distance was effectively shortened, the energy loss was reduced, and luminol achieved a high ECL efficiency. More importantly, PtCu-grafted h-MPF (PtCu/h-MPF) was proposed as a novel quencher. The UV-vis spectra of PtCu/h-MPF partially overlap with the ECL spectra of Mn SANE/PEI-luminol, which can effectively trigger the ECL-RET behavior between the donor and the acceptor. The multiple quenching effect on Mn SANE/PEI-luminol was achieved, which significantly improved the sensitivity of the immunosensor. The prepared immunosensor exhibited good linearity in the concentration range of 10^-5 to 80 ng/mL. The results indicate that this work provides a new method for the early detection of CEA in clinical diagnosis.

Ultrasensitive Photoelectrochemical Immunoassay Strategy Based on Bi2S3/Ag2S for the Detection of the Inflammation Marker Procalcitonin

As an inflammatory marker, procalcitonin (PCT) is more representative than other traditional inflammatory markers. In this work, a highly efficient photoelectrochemical (PEC) immunosensor was constructed based on the photoactive material Bi₂S₃/Ag₂S to realize the sensitive detection of PCT. Bi₂S₃ was prepared by a hydrothermal method, and Ag₂S quantum dots were deposited on the ITO/Bi₂S₃ surface via in situ reduction. Bi₂S₃ is a kind of admirable photoelectric semiconductor nanomaterial on account of its moderate bandgap width and low binding rate of photogenerated electron holes, which can effectively convert light energy into electrical energy. Therefore, based on the energy level matching principle of Bi₂S₃ and Ag₂S, a labeled Bi₂S₃/Ag₂S PEC immunosensor was constructed, and the sensitive detection of PCT was successfully established. The linear detection range of the PEC immunosensor was 0.50 pg∙mL^-1 to 50 ng∙mL^-1, and the minimum detection limit was 0.18 pg∙mL^-1. Compared with the traditional PEC strategy, the proposed PEC immunosensor is simple, convenient, and has good anti-interference, sensitivity, and specificity, which could provide a meaningful theoretical basis and reference value for the clinical detection of PCT.

Detection Enhancement of One Multifunctional Cd-Metal-Organic Framework toward Tetracycline Antibiotics by Simply Mixing Eu3+ in Suspension

It is necessary to find more simple methods to improve the detection selectivity and sensitivity of antibiotics. Herein, we constructed a novel three-dimensional (3D) Cd-MOF LCU-117 assembled from p-terphenyl-4,2″,5″,4'-tetracarboxylic acid, which showed a special 3D helical structure with carboxylic acid ligands and nitrogen-containing ligands crossing each other vertically. Luminescence measurements indicated that LCU-117 has high selectivity and sensitivity toward Eu³⁺ through the ratiometric effect. Meanwhile, this complex itself could detect antibiotics oxytetracycline (OTC) through the turn-off mechanism. When Eu³⁺ was added in suspensions of LCU-117 (noted as Eu³⁺@LCU-117), the detection toward OTC was enhanced significantly and visually. The sensing mechanism was investigated in detail by various measurements and theoretical calculations. LCU-117 has a good effect on the logic gate, potential fingerprint detection, and mixed-matrix membranes (MMMs). The practical application for monitoring OTC in water samples also provided a satisfactory result.

Electrochemiluminescence nanoemitters for immunoassay of protein biomarkers

The family of electrochemiluminescent luminophores has witnessed quick development since the electrochemiluminescence (ECL) phenomenon of silicon nanoparticles was first reported in 2002. Moreover, these developed ECL nanoemitters have extensively been applied in sensitive detection of protein biomarker by combining with immunological recognition. This review firstly summarized the origin and development of various ECL nanoemitters including inorganic and organic nanomaterials, with an emphasis on metal-organic frameworks (MOFs)-based ECL nanoemitters. Several effective strategies to amplify the ECL response of nanoemitters and improve the sensitivity of immunosensing were discussed. The application of ECL nanoemitters in immunoassay of protein biomarkers for diagnosis of cancers and other diseases, especially lung cancer and heart diseases, was comprehensively presented. The recent development of ECL imaging with the nanoemitters as ECL tags for detection of multiplex protein biomarkers on single cell membrane also attracted attention. Finally, the future opportunities and challenges in the ECL biosensing field were highlighted.

Ultrasensitive Electrochemiluminescence Biosensor with Silver Nanoclusters as a Novel Signal Probe and α-Fe2O3-Pt as an Efficient Co-reaction Accelerator for Procalcitonin Immunoassay

Herein, a high-efficiency biosensor based on ternary electrochemiluminescence (ECL) system was constructed for procalcitonin (PCT) detection. Specifically, silver nanoclusters (Ag NCs) with stable luminescence properties were prepared with small-molecule lipoic acid (LA) as the ligand, and its ECL emission in persulfate (S₂O₈^2-) was first reported. Meanwhile, the prepared Ag NCs possessed ligand-to-metal charge-transfer characteristics, thus transferring energy from LA to Ag⁺ for luminescence. Based on the small particle size, good biocompatibility, and molecular binding ability, Ag NCs-LA was used as an ideal luminescent probe. In addition, α-Fe₂O₃-Pt was introduced to facilitate the activation of S₂O₈^2-, thereby generating more sulfate radicals to react with the free radicals of Ag NCs to enhance ECL emission. The synergistic effect of the variable valence state of transition metals and high catalytic activity of noble metals endows α-Fe₂O₃-Pt with excellent catalytic ability for S₂O₈^2-. Importantly, the sensing mechanism was systematically demonstrated by UV-vis, fluorescence, and ECL analysis, as well as density functional theory calculations. At last, NKFRGKYKC was designed for specific immobilization of antibodies, thus releasing the antigen binding sites to improve the antigen recognition efficiency. Based on this, the developed biosensor showed high sensitivity for PCT detection, with a wide linear range (10 fg/mL-100 ng/mL) and a low detection limit (3.56 fg/mL), which could be extended to clinical detection of multiple biomarkers.

Recent trends and advancements in electrochemiluminescence biosensors for human virus detection

Researchers are constantly looking to find new techniques of virus detection that are sensitive, cost-effective, and accurate. Additionally, they can be used as a point-of-care (POC) tool due to the fact that the populace is growing at a quick tempo, and epidemics are materializing greater often than ever. Electrochemiluminescence-based (ECL) biosensors for the detection of viruses have become one of the most quickly developing sensors in this field. Thus, we here focus on recent trends and developments of these sensors with regard to virus detection. Also, quantitative analysis of various viruses (e.g., Influenza virus, SARS-CoV-2, HIV, HPV, Hepatitis virus, and Zika virus) with a specific interest in Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) was introduced from the perspective of the biomarker and the biological receptor immobilized on the ECL-based sensors, such as nucleic acids-based, immunosensors, and other affinity ECL biosensors.

Research progress on near-infrared long persistent phosphor materials in biomedical applications

After excitation is stopped, long persistent phosphor materials (LPPs) can emit light for a long time. The most important feature is that it allows the separation of excitation and emission in time. Therefore, it plays a vital role in various fields such as data storage, information technology, and biomedicine. Owing to the unique mechanism of storage and luminescence, LPPs can avoid the interference of sample autofluorescence, as well as show strong tissue penetration ability, good afterglow performance, and rich spectral information in the near-infrared (NIR) region, which provides a broad prospect for the application of NIR LPPs in the field of biomedicine. In recent years, the development and applications in biomedical fields have been advanced significantly, such as biological imaging, sensing detection, and surgical guidance. In this review, we focus on the synthesis methods and luminescence mechanisms of different types of NIR LPPs, as well as their applications in bioimaging, biosensing detection, and cancer treatment in the field of biomedicine. Finally, future prospects and challenges of NIR LPPs in biomedical applications are also discussed.

Construction of efficient electrochemiluminescence resonance energy transfer sensor based on SnO2/SnS2QDs-Ru@IRMOF-3 composite for sensitive detection of procalcitonin

An efficient electrochemiluminescence resonance energy transfer (ECL-RET) method is proposed which combines the luminescent materials of tris(4,4'-dicarboxylicacid-2,2'-bipyridyl) ruthenium(II) (energy donor) and tin dioxide and tin disulfide quantum dots (SnO₂/SnS₂QDs) (energy acceptor) into the isoreticular metal - organic framework-3 (IRMOF-3) material to form a composite. In this mode, the distance between the energy donor and the acceptor was greatly shortened, reducing the energy loss, and thereby effectively improving RET efficiency and further significantly improving the ECL signal. The obtained composite (SnO₂/SnS₂QDs-Ru@IRMOF-3) was combined with sandwich immunoreaction to construct an ECL immunosensor for the sensitive detection of procalcitonin (PCT). Under the optimized experimental conditions with a working potential of - 1.48 V (vs Ag/AgCl), the proposed PCT biosensor exhibited a linear concentration range of 1 × 10^-4-200 ng mL^-1, with a detection limit of 0.029 pg mL^-1 (S/N = 3). The biosensor was used to detect PCT in actual samples. The biosensor has broad application prospects in biological analysis and clinical diagnosis due to its high sensitivity, good selectivity, and good stability.

Zinc-Based Metal-Organic Framework with MLCT Properties as an Efficient Electrochemiluminescence Probe for Trace Detection of Trenbolone

In this work, we utilized polycyclic aromatic hydrocarbon (PAH) derivatives as ligands to develop a zinc-based metal-organic framework (Zn-MOF) as an effective detection probe to construct an electrochemiluminescence (ECL) sensor for trenbolone detection. As traditional ECL emitters, PAHs and their derivatives have limited luminescence efficiency because of the aggregation-induced quenching (ACQ) effect. Therefore, Zn-PTC was designed by the coordination of 3,4,9,10-perylenetetracarboxylic (PTC) in the MOF to eliminate the ACQ effect. Meanwhile, Zn-PTC formed based on an aromatic ligand possessed the metal-to-ligand charge-transfer (MLCT) effect, which could transfer the energy of Zn²⁺ to the aromatic ligand for strong luminescence. The ECL efficiency of Zn-PTC was calculated to be approximately 2.2 times that of the ligand (K₄PTC). Second, the Ag@Fe core-shell bimetallic nanocrystal was prepared for efficient activation of persulfate (S₂O₈^2-), thereby generating more sulfate radicals (SO₄^•-) to further promote ECL emission. According to ECL characterizations, UV-vis and fluorescence spectra, and density functional theory calculations, the luminescence and signal amplification mechanisms were investigated. In addition, NKFRGKYKC (NKF) was introduced as an affinity ligand to directionally immobilize the target antibodies, thus releasing specific sites in their Fab fragment to enhance binding activity. Based on the above strategies, the constructed biosensor exhibited high sensitivity, realizing trace detection of TBE with a wide detection range (10 fg/mL-100 ng/mL) and a low detection limit (3.28 fg/mL). This study provided an important reference for sensitive monitoring of steroid pollutants in the environment.

A Portable Microfluidic-Based Electrochemiluminescence Sensor for Trace Detection of Trenbolone in Natural Water

In this study, a portable electrochemiluminescence sensor chip was designed for trenbolone (TBE) trace detection in environmental water. First, a stable ECL signal was obtained with low-toxicity 3,4,9,10-perylenetetracarboxylic acid (PTCA) as a luminophore and persulfate (S₂O₈^2-) as a coreactant. Second, hollow-structured Cu₂MoS₄ was introduced as a coreaction accelerator to catalyze S₂O₈^2- reduction. The reversible conversion of the mixed-valence transition metal ions in Cu₂MoS₄ (Cu⁺/Cu²⁺ and Mo⁴⁺/Mo⁶⁺) greatly promoted the generation of the sulfate radical (SO₄^•-). Meanwhile, the special porous structure of Cu₂MoS₄ possessed a large specific surface area, thus enhancing its catalytic performance. Based on these enhancement mechanisms, a strong ECL signal was acquired, which improved the detection sensitivity of the constructed sensor. Importantly, a microfluidic chip was introduced for sensing detection, thereby improving the practicality of the sensor. The developed sensor chip was miniature and portable, exhibiting high sensitivity for TBE detection with a wide linear range (10 fg/mL-100 ng/mL) and lower detection limit (3.32 fg/mL). This was of great significance for timely and rapid analysis of steroid pollutants in natural water.

Highly Efficient PTCA/Co3O4/CuO/S2O82- Ternary Electrochemiluminescence System Combined with a Portable Chip for Bioanalysis

Herein, we reported an efficient electrochemiluminescence (ECL) biosensor chip for sensitive detection of neuron-specific enolase (NSE). First, 3,4,9,10-perylenetetracarboxylic acid with good luminescence characteristics was used as a luminophore to obtain a stable ECL signal. Subsequently, hollow porous Co₃O₄/CuO concave polyhedron nanocages (CPNCs) were designed as co-reaction promoters to amplify the luminescence signals for highly sensitive trace detection of NSE. In brief, the rapid cyclic conversion of Co³⁺/Co²⁺ and Cu²⁺/Cu⁺ redox pairs could continuously catalyze the reduction of persulfate (S₂O₈^2-), thus providing a large number of essential active intermediates (SO₄^•-) for ECL emission. Meanwhile, the unique structure of Co₃O₄/CuO CPNCs possessed a large specific surface area, which greatly improved its catalytic efficiency. Third, NKFRGKYKC was developed as an affinity ligand for specific antibody fixation, which improved incubation efficiency and protected bioactivity of antibodies. Finally, we independently designed a microchip and applied it for ECL detection to improve the practical application ability of the sensor. The developed biosensor exhibited good sensitivity with a wide linear range (10 fg/mL to 100 ng/mL) and a low detection limit (3.42 fg/mL), which played an active role in the clinical application of sensing analysis.

Progress and Prospects of Electrochemiluminescence Biosensors Based on Porous Nanomaterials

Porous nanomaterials have attracted much attention in the field of electrochemiluminescence (ECL) analysis research because of their large specific surface area, high porosity, possession of multiple functional groups, and ease of modification. Porous nanomaterials can not only serve as good carriers for loading ECL luminophores to prepare nanomaterials with excellent luminescence properties, but they also have a good electrical conductivity to facilitate charge transfer and substance exchange between electrode surfaces and solutions. In particular, some porous nanomaterials with special functional groups or centered on metals even possess excellent catalytic properties that can enhance the ECL response of the system. ECL composites prepared based on porous nanomaterials have a wide range of applications in the field of ECL biosensors due to their extraordinary ECL response. In this paper, we reviewed recent research advances in various porous nanomaterials commonly used to fabricate ECL biosensors, such as ordered mesoporous silica (OMS), metal-organic frameworks (MOFs), covalent organic frameworks (COFs) and metal-polydopamine frameworks (MPFs). Their applications in the detection of heavy metal ions, small molecules, proteins and nucleic acids are also summarized. The challenges and prospects of constructing ECL biosensors based on porous nanomaterials are further discussed. We hope that this review will provide the reader with a comprehensive understanding of the development of porous nanomaterial-based ECL systems in analytical biosensors and materials science.

Efficient ABEI-Dissolved O2-Ce(III, IV)-MOF Ternary Electrochemiluminescent System Combined with Self-Assembled Microfluidic Chips for Bioanalysis

A signal-amplified electrochemiluminescent (ECL) sensor chip was developed for sensitive analysis of procalcitonin (PCT). Herein, we first prepared a self-enhanced luminophore, which enhanced ECL responses through intramolecular reactions. Second, Au-Pd bimetallic nanocrystals and mixed-valence Ce-based metal-organic frameworks (MOFs) were introduced as co-reaction promoters to facilitate the reduction of dissolved O₂. Based on the synergistic catalysis of Au and Pd, the spontaneous cyclic reaction of Ce(III)/Ce(IV), and the high electrochemical active surface area of Ce(III, IV) MOF, a large number of superoxide anion radicals (O₂^•-) and hydroxyl radicals (OH^•) were produced. Therefore, the luminescence efficiency of N-(aminobutyl)-N-(ethylisoluminol)-dissolved O₂ (ABEI-O₂) systems were greatly improved, providing a new prospect for the application of dissolved O₂ in ECL analysis. In addition, the affinity peptide ligands were used for the directional connection of antibodies to provide protection for the bioactivity of the proposed sensor. Finally, the microfluidic technology was applied to ECL analysis to integrate the three-electrode detection system into the self-assembled microfluidic chip, which realized the automation and portability of the detection process. The developed sensor showed high sensitivity for PCT detection with a detection limit of 3.46 fg/mL, which possessed positive significance for the clinical diagnosis of sepsis.

Biocatalysis-mediated MOF-to-prussian blue transformation enabling sensitive detection of NSCLC-associated miRNAs with dual-readout signals

Sensitive and accurate miRNAs assay is critical for early diagnosis of non-small-cell lung carcinomas (NSCLC). Herein, we demonstrate a photothermal and electrochemical dual-readout assay method for miRNA detection based on a novel biocatalysis-mediated MOF-to-prussian blue (PB) transformation (BMMPT) strategy and the catalytic hairpin assembly (CHA) amplification strategy. It is found that the Fe²⁺-based MOF (MOF-Fe²⁺) can act as the Fe²⁺ source to react with K₃[Fe(CN)₆], leading to the in-situ formation of prussian blue (PB) on MOF-Fe²⁺. Due the inherent near-infrared (NIR) photothermal conversion ability and electrochemical signal of PB, the resulting PB@MOF-Fe²⁺ is employed to arouse temperature readout or electrochemical signal. The presence of target miRNA-21 triggers the CHA reaction on magnetic beads (MBs), resulting the capture of numerous glucose oxidase (GOx) tags on MBs. The GOx tags then catalyze the generation of H₂O₂ using glucose as substrate. The H₂O₂ is used to inhibit the MOF-to-PB transformation process by oxidizing Fe²⁺ into Fe³⁺, leading to the decrease in temperature and electrochemical readout aroused by PB@MOF-Fe²⁺. By this means, a signal-off assay mode with dual readout is established for miRNA-21. Under the optimal conditions, using temperature readout or electrochemical readout, miRNA-21 can be detected at concentrations as low as 0.3 fM and 0.32 fM, respectively. Moreover, the developed method is successfully applied to evaluate the expression level of miRNA-21 in serum of NSCLC patients. This work not only provides a practical tool for NSCLC diagnosis but also presents the new features of MOF materials as signal transduction tags.

Rapid FRET-based homogeneous immunoassay of procalcitonin using matched carbon dots labels

A novel method for the detection of procalcitonin in a homogeneous system by matched carbon dots (CDs) labeled immunoprobes was proposed based on the principle of FRET and double antibody sandwich method. Blue-emitting carbon dots with a strong fluorescence emission range of 400-550 nm and red-emitting carbon dots with the best excitation range of 410-550 nm were prepared before they reacted with procalcitonin protoclone antibody pairs to form immunoprobes. According to the principles of FRET, blue-emitting carbon dots were selected as the energy donor and red-emitting carbon dots as the energy receptor. The external light source excitation (310 nm) could only cause weak luminescence of CDs. However, once procalcitonin was added, procalcitonin and antibodies would be combined with each other quickly (≤20 min). Here, blue-emitting carbon dots acquired energy could be transferred to red-emitting carbon dots efficiently, causing the emitted fluorescence enhancement of red-emitting carbon dots. The fluorescence detection results in PBS buffer solution and diluted rabbit blood serum showed that the fluorescence intensity variation was linear with the concentration of procalcitonin. There was a good linear relationship betweenF/F0 and procalcitonin concentrations in PBS buffer solution that ranged from 0 to 100 ng ml^-1, and the linear equation wasF/F0 = 0.004 *C_pct + 0.98359. Detection in the diluted rabbit serum led to the results that were linear in two concentration ranges, including 0-40 ng ml^-1and 40-100 ng ml^-1, and the detection limit based on 3σK^-1was 0.52 ng ml^-1. It is likely that this matched CDs labeled immunoprobes system can provide a new mode for rapid homogeneous detection of disease markers.

Copper-Doped Terbium Luminescent Metal Organic Framework as an Emitter and a Co-reaction Promoter for Amplified Electrochemiluminescence Immunoassay

This work designed a signal amplification strategy for construction of a highly sensitive electrochemiluminescence (ECL) biosensor by doping Cu²⁺ in a terbium luminescent metal organic framework (Cu:Tb-MOF) to act as a co-reaction promoter, which enhanced the generation of SO₄^•- radical during the cathodic process in the presence of K₂S₂O₈ as a co-reactant. The porous and hollow morphology and the size of Cu:Tb-MOF could be efficiently tuned via changing the molar ratio of Cu²⁺ and Tb³⁺ and the reaction time, which were related to the specific surface area, pore diameter, and the ECL intensity of the MOF structure. To further improve the sensitivity of the ECL biosensor, H₂O₂ was introduced into the ECL system to act as another co-reaction promoter, leading to a new ECL mechanism involving dual co-reaction promoters. In view of the low electron transfer resistance of Cu:Tb-MOF, a label-free ECL immunosensor was conveniently constructed by co-immobilizing Cu:Tb-MOF and the capture antibody on the electrode surface. Using pro-gastrin-releasing peptide (ProGRP, a biomarker of small-cell lung cancer) as the model target, the proposed immunosensor exhibited excellent performance with a detection range of 1.0 pg·mL^-1 to 50 ng·mL^-1 and a limit of detection down to 0.68 pg·mL^-1 (3σ). This work demonstrated a strategy to use the MOF structures as both an emitter and a co-reaction promoter for amplified ECL emission and proposed an innovative route to extend the application of lanthanide MOFs.

Peptide-Based Electrochemiluminescence Biosensors Using Silver Nanoclusters as Signal Probes and Pd-Cu2O Hybrid Nanoconcaves as Coreactant Promoters for Immunoassays

Metal nanoclusters (NCs) possess high light stability and biocompatibility because of their unique quantum size effect, which has gradually become a new type of electrochemiluminescence (ECL) nanomaterial for immunoassays. However, the luminescence efficiency of metal NCs is too low to meet the needs of trace analysis, which limits its application. Herein, Ag NCs served as signal probes and Pd-Cu₂O hybrid nanoconcaves served as coreaction promoters, developing a highly efficient peptide-based biosensor for neuron-specific enolase (NSE) detection. Utilizing the reversible cycle of Cu⁺/Cu²⁺ and the reduction characteristics of Pd NPs, Pd-Cu₂O greatly accelerates the reduction of S₂O₈^2-. Meanwhile, Pd-Cu₂O has good hydrogen evolution activity, which promotes the generation of oxygen by improving the redox efficiency of the overall reaction, thus increasing the yield of active intermediates (OH^•) to promote the reduction of S₂O₈^2-. Specially, this is an effective attempt to use the hydrogen evolution reaction (HER) to accelerate the ECL emission of the S₂O₈^2- system. In addition, a short peptide ligand (NARKFYKGC, NFC) was developed to implement the targeted immobilization of antibodies, which can specifically bind to the Fc fragment of antibodies, thereby avoiding the occupation of the antigen binding site (Fab fragment). The introduction of NFC not only improves the binding efficiency of antibodies but also protects its bioactivity, thus significantly improving the sensitivity of the biosensor. Based on these strategies, the proposed biosensor provides a new perspective for the applications of metal NCs in ECL systems.

Label-free immunosensor for cardiac troponin I detection based on aggregation-induced electrochemiluminescence of a distyrylarylene derivative

Herein, the aggregation-induced electrochemiluminescence (AIECL) of a distyrylarylene derivative, 4,4'-bis(2,2-diphenylvinyl)-1,1'-biphenyl (DPVBi), was investigated for the first time. This luminophore exhibits significantly enhanced photoluminescence (PL) and electrochemiluminescence (ECL) emission with the increases of water content in organic/water mixtures. This high luminescence efficiency of DPVBi in aggregate state is due to the fact that the aggregates can reduce the energy loss by restricting the intramolecular motions. The ECL behavior of DPVBi in acetonitrile was investigated by ECL transients and so-called "half-scan" technology, where singlet-singlet annihilation ECL was generated under continuous potential switching. The DPVBi nanobulks (DPVBi NBs) were prepared to improve its application in aqueous media, which could be conveniently cast on electrode surface for developing sensing platform due to its good film-forming nature. The constructed heterogeneous AIECL platform can produce reductive-oxidative and oxidative-reductive ECL by using trimethylamine (TEA) and potassium peroxodisulfate (K₂S₂O₈) as coreactant. On the basis of the higher ECL efficiency of DPVBi NBs/TEA system, a label free immunosensor for cardiac troponin I (cTnI) was developed with the assistance of electrodeposited gold nanoparticles, and it showed a wide linear range of 20 ng/mL~100 fg/mL and low detection limit of 43 fg/mL. Moreover, the constructed immunosensor also exhibited good specificity, stability and satisfied performance in practical sample analysis.