Peptide Sequence Modulating the Analytical Performance of Electrogenerated Chemiluminescence Peptide-Based Biosensors for Matrix Metalloproteinase 2.

Electrogenerated chemiluminescence (ECL) methods have been widely used in clinical diagnosis. Although ECL peptide-based biosensors continue to grow with good sensitivity and signal flexibility, little emphasis has been placed on the effect of the peptide sequence on ECL sensitivity. We herein studied the nuanced effects of different peptide sequences on the analytical performance of ECL peptide-based biosensors for matrix metalloproteinase 2 (MMP-2) assay, in which [(pbz)Ir(DMSO)Cl] (pbz = 3-(2-pyridyl)benzoic acid) was used as the ECL emitter while a specific peptide was used as the molecular recognition element.

Nonemissive Iridium(III) Solvent Complex as a Self-Reporting Photosensitizer for Monitoring Phototherapeutic Efficacy in a "Signal on" Mode.

Photodynamic therapy (PDT) has long been receiving increasing attention for the minimally invasive treatment of cancer. The performance of PDT depends on the photophysical and biological properties of photosensitizers (PSs). The always-on fluorescence signal of conventional PSs makes it difficult to real-time monitor phototherapeutic efficacy in the PDT process.

Coordination-Based Site-Specific Labeling Strategy for Electrogenerated Chemiluminescence Biosensing of Matrix Metalloproteinase 2.

Matrix metalloproteinase 2 (MMP-2) is an important biomarker for some diseases. Herein, one first-case coordination-based site-specific labeling strategy is proposed for electrogenerated chemiluminescence (ECL) biosensing of MMP-2 by employing an iridium(III) solvent complex as a signal reagent and a histidine (His)-containing peptide as a molecular recognition substrate. One ECL probe was prepared via coordination labeling of the His-containing peptide with one iridium(III) solvent complex ([(3-(2-pyridyl)benzoic acid)Ir(DMSO)Cl], Ir1-DMSO).

Iridium(III) solvent complex-based electrogenerated chemiluminescence method for the detection of 3-methylhistidine in urine.

3-Methylhistidine (3-MeHis) is increasingly used as an indicator of muscle protein breakdown. The development of a sensitive, simple, and non-invasive method for 3-MeHis assay is important in clinical practice. Herein, a sensitive, simple, and non-invasive electrogenerated chemiluminescence (ECL) method was proposed for the quantitation of 3-MeHis in urine by using an iridium(III) solvent complex ([Ir(dfppy)(DMSO)Cl], dfppy = 2-(2,4-difluorophenyl)pyridine, Ir-DMSO) as a signal reagent.

Electrogenerated Chemiluminescence Biosensor for Quantization of Matrix Metalloproteinase-3 in Serum via Target-Induced Cleavage of Oligopeptide.

A highly sensitive and selective electrogenerated chemiluminescence (ECL) biosensor was developed for the determination of matrix metalloproteinase 3 (MMP-3) in serum via the target-induced cleavage of an oligopeptide. One ECL probe (named as Ir-peptide) was synthesized by covalently linking a new cyclometalated iridium(III) complex ([(3-pba)Ir(bpy-COOH)](PF)) (3-pba = 3-(2-pyridyl) benzaldehyde, bpy-COOH = 4'-methyl-2,2'-bipyridine-4-carboxylic acid) with an oligopeptide (CGVPLSLTMGKGGK). An ECL biosensor was fabricated by firstly casting Nafion and gold nanoparticles (AuNPs) on a glassy carbon electrode and then self-assembling both of the ECL probes, 6-mercapto-1-hexanol and zwitterionic peptide, on the electrode surface, from which the AuNPs could be used to amplify the ECL signal and Ir-peptide could serve as an ECL probe to detect the MMP-3.

Photoluminescence-Electrochemiluminescence Dual-Mode Sensor Arrays for Histidine and Its Metabolite Discrimination and Disease Identification.

Histidine (His) and its metabolite analysis is significant due to their vital roles in the diagnosis of diseases. In practical applications, simple and effective detection and discrimination of these metabolic species are still a great challenge due to their highly similar structures. Herein, photoluminescence (PL)-electrochemiluminescence (ECL) dual-mode sensor arrays consisting of a series of sensing elements were proposed for simultaneous quantitation and accurate discrimination of His and its four key metabolites (including histamine, imidazole-4-acetic acid, -acetylhistamine, and imidazole propionate).

Electrochemiluminescence bioassay with anti-fouling ability for determination of matrix metalloproteinase 9 secreted from living cells under external stimulation.

An electrochemiluminescence (ECL) bioassay with high sensitivity and anti-fouling ability was developed for determination of matrix metalloproteinase 9 (MMP-9) secreted from living cells under external stimulation. A peptide with sequence of CLGRMGLPGK and a new cyclometalated iridium(III) complex bearing carboxyl group, (pq)Ir(dcbpy) (pq = 2-phenylquinoline, dcbpy = 2,2'-bipyridyl-4,4'-dicarboxyli acid, abbreviated as Ir) were employed as molecular recognition substrate and ECL emitter, respectively. The peptide was labelled with the Ir to form Ir-peptide as ECL probe.

A sensitive and noninvasive cyclic peptide-based electrogenerated chemiluminescence biosensing method for the determination of sweat glucose.

A sensitive and noninvasive cyclic peptide-based electrogenerated chemiluminescence biosensing method for the determination of sweat glucose was developed. Glucose can be quantified in sweat samples with a recovery of 93%-113% one-step recognition, which is promising for the determination of sweat glucose.

Label-Free Electrogenerated Chemiluminescence Aptasensing Method for Highly Sensitive Determination of Dopamine via Target-Induced DNA Conformational Change.

A label-free electrogenerated chemiluminescence (ECL) aptasensing method for highly sensitive determination of dopamine (DA) was developed based on target-induced DNA conformational change. After anti-DA specific aptamer, as molecular recognition element, was hybridized with a capture ss-DNA (complementary with the aptamer), the formed double-strand DNA (ds-DNA) was self-assembled onto the surface of a gold electrode, and then Ru(phen), as ECL reagent, was intercalated into ds-DNA to form an ECL biosensing platform. In the presence of DA, DA bound with its aptamer and target-induced DNA conformational change occurred, resulting in the dissociation of ds-DNA, the release of intercalated Ru(phen) from the electrode surface, and the decrease of ECL intensity.

Rationally Designed Matrix-Free Carbon Dots with Wavelength-Tunable Room-Temperature Phosphorescence.

We report the rational design of the matrix-free carbon dots (C-dots) with long wavelength and wavelength-tunable room-temperature phosphorescence (RTP). Taking advantage of microwave-assisted heating treatment, three RTP C-dots in boric acid (BA) composites are synthesized by using diethylenetriaminepentakis (methylphosphonic acid) as a multiple-sites crosslink agent, a moderately acid catalyst and P source; phenylenediamines (either o-PD, m-PD, or p-PD, respectively) as building block while BA as a carbonization-retardant matrix. After the water-soluble BA matrix is removed by dialysis, three matrix-free C-dots are obtained with RTP emission at 540, 550 and 570 nm under an excitation wavelength of 365 nm.

Iridium(III) solvent complex-based electrogenerated chemiluminescence and photoluminescence sensor array for the discrimination of bases in oligonucleotides.

Development of rapid and sensitive method for the discrimination of bases in oligonucleotides is of great importance in clinical diagnosis. Here, we demonstrate the first case of single iridium(III) solvent complex-based electrogenerated chemiluminescence (ECL) and photoluminescence (PL) sensor array for the discrimination of bases in oligonucleotides. One iridium (III) solvent complex ([Ir(ppy)(DMSO)Cl], ppy = 2-phenylpyridine, probe 1) was designed as both ECL and PL probe while five bases (guanine, adenine, cytosine, thymine and uracil) were chosen as analytes.

Mechano-chromic and mechano-enhanced electrogenerated chemiluminescence of tetra[4-(4-cyanophenyl)phenyl]ethene.

Mechano-chromic and mechano-enhanced electrogenerated chemiluminescence (ECL) from tetra[4-(4-cyanophenyl)phenyl]ethene (TCPPE) is reported for the first time. TCPPE displays intense mechano-enhanced ECL ( = 12.1%, = 75.

Highly Efficient Aggregation-Induced Enhanced Electrochemiluminescence of Cyanophenyl-Functionalized Tetraphenylethene and Its Application in Biothiols Analysis.

Exploring new electrochemiluminescence (ECL) luminophores with high ECL efficiency and good stability in aqueous solution is in great demand for biological sensing. In this work, highly efficient aggregation-induced enhanced ECL of cyanophenyl-functionalized tetraphenylethene (tetra[4-(4-cyanophenyl)phenyl]ethene, TCPPE) and its application in biothiols analysis were reported. TCPPE contains four 4-cyanophenyl groups covalently attached to the tetraphenylethene (TPE) core, generating a nonplanar three-dimensional twisted conformation structure.

Multifunctional zeolitic imidazolate framework-8 for real-time monitoring ATP fluctuation in mitochondria during photodynamic therapy.

Zeolitic imidazolate framework-8 (ZIF-8) is emerging as a promising vector in encapsulation and delivery of imaging agents or drugs. Adenosine triphosphate (ATP) is the primary energy source in cells and plays a key role in many cellular processes. Although numerous probes have been developed for ATP detection, only a few of them were used to real-time monitor ATP fluctuation in mitochondria during photodynamic therapy (PDT).

Synthesis of multiple-color emissive carbon dots towards white-light emission.

Multiple-color emissive carbon dots (C-dots) are gaining increasing attention in various fields. Herein, we report a facile solvothermal method for the synthesis of multiple-color emissive C-dots with the aim of white-light emission. Under single ultraviolet-light excitation, three C-dots emit a easily controlled fluorescent emission wavelength at 440 nm, 500 nm and 610 nm by using different three amines (either ammonium hydroxide, ethylenediamine or p-phenylenediamine, respectively) and pyromellitic dianhydride as molecular precursors while another three C-dots emit a controllable fluorescent emission wavelength at 500 nm, 550 nm and 585 nm by using same three amines and naphthalene-1,4,5,8-tetracarboxylic dianhydride as molecular precursors.

Matrix-Free and Highly Efficient Room-Temperature Phosphorescence Carbon Dots towards Information Encryption and Decryption.

Designing efficient room-temperature phosphorescence (RTP) carbon dots (C-dots) without the need of an additional matrix is important for various applications. Herein, matrix-free and highly efficient C-dots with yellow-green RTP emission have been successfully synthesized towards information encryption and decryption. Phytic acid (PA) and triethylenetetramine are used as molecular precursors, and a facile microwave-assisted heating method is selected as synthesis method.

Cyclometalated Iridium Complex as Off-On-Off Reversible Photoluminescence Probe for Redox Cycle /HO in Living Cells.

The development of new methods for the detection of redox cycle is important for biological and clinical diagnoses. Here, a new cyclometalated iridium complex, (4-(2-pyridyl) benzaldehyde)Ir (5-chloro-1,10-phenanthroline) ([(4-pba)Ir(5-Cl-phen)]PF, probe ), has been synthesized and applied to rapid, sensitive, and reversible detection and imaging of redox cycle /HO in living cells. The probe is synthesized by using 4-(2-pyridyl) benzaldehyde as main ligand and 5-chloro-1,10-phenanthroline as ancillary ligand.

A "switch-on" photoluminescent and electrochemiluminescent multisignal probe for hypochlorite via a cyclometalated iridium complex.

A new cyclometalated iridium complex, [(bt)Ir(bpy-Fc)]PF (bt = 2-phenylbenzothiazole, bpy-Fc = 4-ferrocenecarbonyl hydrazinocarbonyl-4'-methyl- 2,2'-bipyridine) (probe 1) was designed and synthesized for rapid photoluminescent (PL) and electrochemiluminescent (ECL) sensing of hypochlorite (ClO). Probe 1 exhibits weak PL and ECL emissions attributed to its electron transfer process. In the presence of ClO, the cleavage of the hydrazine-linked Fc moiety in probe 1 led to the enhancement of both PL and ECL.