Peroxyoxalate Chemiluminescence System Research Articles

Catalytic and anti-cancer properties of platinum, gold, silver, and bimetallic Au-Ag nanoparticles synthesized by Bacillus sp. bacteria

Metallic nanoparticles play a significant role in the catalysis of chemical processes, besides, bimetallic nanoparticles with abundant active sites can reduce metallic nanoparticles toxicity in addition to increasing their catalytic performances. In this work, the platinum, gold, and silver nanoparticles are bio-synthesized using a native bacterium (GFCr-4). Also, the Au-Ag and Au@Ag bimetallic nanoparticles with alloy and core-shell structures, respectively, are biologically synthesized. To improve the synthesis, the effects of various factors like pH, temperature, electron donor, and ionic liquids were investigated. The as-synthesized nanoparticles were characterized with different techniques. The microscope images and dynamic light scattering (DLS) analysis confirm the uniform distribution of as-synthesized nanoparticles with average sizes of 25, 30, 47, 77, and 86 nm obtained for Ag, Au, Pt, Au-Ag alloy, and Au@Ag core-shell, respectively. The catalytic performances of as-synthesized nanoparticles were investigated. The Au-Ag alloy nanoparticles exhibit better catalytic performance than the as-synthesized metallic Au nanoparticles, according to the Gewald reaction. According to the photocatalytic study, the yield can be increased by up to 92% by using PtNPs in the presence of a green LED. Additionally, for the first time, PtNPs were utilized as an effective catalyst in a peroxyoxalate chemiluminescence (POCL) system in the presence of nuclear fast red (NFR) as a novel fluorophore. In addition, the results of the MTT (3-[4,5-dimethylthiazol-2-yl]−2,5 diphenyl tetrazolium bromide) assay revealed that the synthesized eco-friendly nanoparticles have a low effect on the lethality of 3T3 normal cells whereas MCF-7 cancer cells were inhibited up to 77.3% after treatment by PtNPs nanoparticles.

Pyridine-2-yl Quinoxaline (2-CPQ) Derivative As a Novel Pink Fluorophore: Synthesis, and Chemiluminescence Characteristics.

Quinoxaline derivatives are well-known N-heterocycles with pharmacological and fluorescence activities. Almost all quinoxaline derivatives with extensive π-conjugation have been introduced as fluorophores which emit blue and green light. For the first time, we designed and synthesized 6-chloro-2,3 di(Pyridine-2yl) quinoxaline (2-CPQ) as a pink fluorophore in acetonitrile medium by simple route at room temperature whitin 30min. The synthesized quinoxaline was identified using 1H, 13C NMR, MS, and FT-IR spectroscopy. Our results showed that the iodine-catalyzed method for both oxidation and cyclization during the synthesis of quinoxaline from pyridine 2-carbaldehyde was straightforward, efficient, and clean. All of the mentioned characterization devices confirmed the synthesis of 2-CPQ.Moreover, we studied the photophysical properties of the synthesized fluorophore in which The UV-Vis absorption spectrum of 2-CPQ in DMF were three peaks at 451, 518 and 556nm. Based on photophysical properties investigation, 2-CPQ shows good fluorescence with maximum peaks 607 and 653nm in DMF as solvent (фF = 0.21). Hence, the fluorophore was applied in the peroxyoxalate chemiluminescence system. The reaction of imidazole, H2O2, and bis (2,4,6-trichlorophenyl) oxalate (TCPO) can transfer energy to a 6-chloro-2,3 di(pyridine-2yl) quinoxaline. In this process, dioxetane was synthesized, which chemically initiated the electron exchange luminescence (CIEEL) mechanism and led to pink light emission. We anticipate our synthesized fluorophores 2-CPQ will have great potential applications in imaging and medical markers.

A robust gold nanocluster-peroxyoxalate chemiluminescence system for highly sensitive detection of cyanide in environmental water

Detection of cyanide (CN-) ion is of essential importance due to its high toxicity to human life. Herein, we developed a gold nanoclusters (AuNCs)-peroxyoxalate chemiluminescence (CL) system for ultrasensitive detection of CN- in environmental water samples. Bis (2,4,5-trichloro-6-carbopentoxyphenyl) oxalate (CPPO)-hydrogen peroxide (H2O2) CL reaction was utilized to produce high energy intermediates, namely energy donors, and AuNCs served as the acceptors to harvest the energy via CL resonance energy transfer (CRET) process. Besides, it was demonstrated that AuNCs also could act as a catalyst to enhance the generation of the high energy intermediate; and the AuNCs also had an aggregation induced emission (AIE) effect in the organic solvent that was used in CPPO-based CL system. In the presence of CN-, AuNCs can be etched by CN- due to the Elsner complexation reaction between CN- and AuNCs, and thus both of the quantum yield and catalytic activity decreased remarkably. As a result, significant quenching of CPPO-AuNCs CL was observed. The CL intensity decreased linearly in the concentration range of 2.5–125 μg/L CN-, and the detection limit was calculated to be 0.55 μg/L, 10-fold lower than that obtained by the fluorescent sensing of AuNCs. The relative standard deviation was 4.3% for seven parallel measurements of 100 μg/L CN-. It also exhibited high selectivity and favorable anti-interference capability. The sensing system was used for detection of CN- in five standard water samples, and the analytical results were in good agreement with the certified values. Overall, the simple and sensitive CL sensing platform offers a promising tool for convenient detection of CN- in environmental water samples.

Two Pyrene-Based Metal-Organic Frameworks for Chemiluminescence.

Fluorescent agents play an important role in the peroxyoxalate chemiluminescence system. However, the effect of different frameworks on chemiluminescence (CL) has not been explored. Herein two pyrene-based metal-organic frameworks (MOFs), [Pb2L]n·2nDMA·2nH2O (1) and [(Ca2L)·(DMF)3]n·2.5nDMF·6nH2O (2) (H4L = 5,5'-(-pyrene-1,6-diyl)-diisophthalic acid; DMA = N,N'-dimethylacetamide; DMF = N,N'-dimethylformamide), have been successfully synthesized and are applied to CL. They both exhibit strong and lasting emission that is visible to the naked eye and is significantly stronger than that of the ligand. More importantly, compared with 2, 1 has notably better CL performance. We infer that the reason may be that 1 has higher stability and larger open channels, which can avoid the aggregation of organic ligands as well as provide an effective pathway for the active substance to diffuse into the channels.

A proposed image-based detection of methamidophos pesticide using peroxyoxalate chemiluminescence system

AbstractPesticides pose a serious public health risk due to their toxicity, such as in the case of the widely distributed organophosphorus pesticide methamidophos. There is a strong need to develop a simple, rapid, and cost-effective method of detecting methamidophos residues; thus, this study proposes the TCPO-Rubrene-H2O2 chemiluminescence (CL) system as a means of pesticide detection via quenching effect. The results show that the methamidophos concentration is inversely proportional to the CL system's light output as confirmed through fluorescence spectroscopy and Batch Measure Macro (BMM) analysis. The light intensity differences were correlated with the methamidophos concentration with both methods showing linear trends. Both the digital camera and the smartphone camera BMM analyses displayed good sensitivity, with respective detection limits of 1.6 μg/mL and 1.0 μg/mL and respective quantitation limits of 5.0 μg/mL and 3.0 μg/mL. Both also showed good linearity within the 100-10000 μg/mL range, suggesting viability as alternatives to the fluorescence spectrometer; however, the light intensity difference values per pesticide concentration of both camera systems were significantly different from one another owing to differences in camera features.

Fabrication of a new peroxyoxalate chemiluminescence system containing the Cy3 fluorophore and its application to carvedilol detection

Cy3 is a dye that has been widely applied in fluorescence microscopy and single molecule detection due to its low hydrophobicity and intense fluorescence emission. As a new application, this study proposes using Cy3 as the fluorophore of a peroxyoxalate chemiluminescence system. The system relies on the oxidative reaction of bis-(2,4,6-trichlorophenyl) oxalate (TCPO) with H2O2 in the presence of imidazole, as the catalyst, to produce dioxetane via a chemically initiated electron exchange luminescence (CIEEL) process, excite Cy3 by the excess energy of the dioxetane and permit Cy3 to emit yellow light. The chemiluminescence behavior of the system is investigated using different concentrations of TCPO, imidazole, the oxidant and Cy3 and by considering non-linear least squares curve fitting of the obtained intensity–time profiles into the pooled intermediate model. The evaluated kinetic parameters include experimental and theoretical maximum intensity, the rise and fall rate constants of the chemiluminescence process, experimental and theoretical time required to reach the maximum intensity and total emission yield. Finally, the developed system is adopted to detect a drug, i.e., carvedilol, in different pharmaceuticals. Under the optimal conditions, the system can provide a linear response for determination of 3 × 10− 7 to 3 × 10− 5 M carvedilol (r > 0.9869, n = 6) and a detection limit of 1.21 × 10− 7 M. The relative standard deviation of the detection results for six repetitive determinations is below 3.47% and the obtained recoveries are 99.6% and 101.9%.

A new cyano-substituted fluorescamine superior to its original form as a fluorescent probe for amino acid detection

Synthesis and spectral study of two new cyano-substituted fluorescamine as the fluorescent probes for amino acid detection have been carried out comparing with the original fluorescamine. Of the three compounds, the derivative with a cyano group at the meta-position on the 4-phenyl group was found to be superior to the original one in the reactivity toward some amino acids as well as the fluorescence intensity of the adducts. The fluorescent amino acid adducts were also applied to the peroxyoxalate chemiluminescence system as the fluorophores, in which the derivative described above was found to be more effective also in chemiluminescence than the original one.

Fluorescence and chemiluminescence behavior of distyrylbenzene bearing two arms of dipicolylaminomethyl groups: Interactions with zinc ion and ATP

The absorption and fluorescence spectral study of the distyrylbenzene bearing two arms of the dipicolylaminomethyl groups, the effective ligands for Zn2+, was studied in the presence of Zn2+ and ATP. Upon complexation of the distyrylbenzene with zinc ions in acetonitrile, enhancement of the fluorescence intensity was observed due to inhibition of intramolecular PET (photo-induced electron transfer) quenching, but no effect was found in aqueous media because the equilibrium laid to the free form of the ligands. In contrast, the addition of ATP disodium salt was effective to enhance the fluorescence intensity of the combination of the distyrylbenzne and Zn2+ in aqueous media. This assembly was applied to the peroxyoxalate chemiluminescence system and a significant increase in the intensity was observed, which provides a potential detection for ATP by chemiluminescence.

Chemiluminescence recognition of berberine triggered by biomimetically synthesized silver nanoparticles

A simple, rapid and sensitive method was developed using silver nanoparticles (Ag-NPs) amplified flow-based peroxyoxalate chemiluminescence system to detect berberine, an anticancer agent. Berberine could dramatically sensitize the emission from oxidation reaction of bis (2,4,6-tricholorophenyl) oxalate (TCPO) with H2O2 catalyzed by silver nanoparticles(Ag-NPs). Under optimized experimental conditions, CL intensity was found to be proportional to the concentration of berberine in the range from 5×10−9 to 5×10−7molL−1 (r>0.9843, n=8) was obtained with a detection limit of 8.7×10−10molL−1. Potential interference by common excipients was also studied. The relative standard deviation for 8 repetitive determinations was less than 3.4% and recoveries of 97.7% and 101.6% were obtained. The Ag nanoparticles were synthesized using Oxalis corniculata plant as green route and characterized using field emission scanning electron microscopy, particle size analyzer and UV–vis Spectroscopy. The method was successfully applied to detect berberine in pharmaceutical formulations.

Determination of reactive oxygen generated from natural medicines and their antibacterial activity

Extracts of 16 natural medicine powders (Galla chinensis, Malloti cortex, Cassiae semen, Sophorae radix, Myricae cortex, Crataegi fructus, Gambir, Mume fructus, Geranii herba, Phellodendri cortex, Coptidis rhizoma, Swertiae herba, and Cinnamomi cortex) were assayed for reactive oxygen concentrations using the peroxyoxalate chemiluminescent detection system. High luminescence intensity was observed in Galla chinensis, Geranii herba, Malloti cortex, Myricae cortex, and Cinnamomi cortex. Additional experiments identified the reactive oxygen species as hydrogen peroxide.Galla chinensis generated 2.4×10−4mol/L hydrogen peroxide from a 1mg/mL solution. In bacterial growth tests, Galla chinensis extract had antibacterial activity against Escherichia coli, Staphylococcus aureus, Bacteroides thetaiotaomicron, Campylobacter sputorum biovar sputorum, Streptococcus salivarius thermophilus, Lactobacillus casei, and Bifidobacterium longum infantis. This antibacterial activity was decreased by the addition of catalase. It revealed that hydrogen peroxide which Galla chinensis produced participated in antibacterial activity.

Sensitive determination of 4-nitrophenol based on its enhancement of a peroxyoxalate chemiluminescence system containing graphene oxide quantum dots and fluorescein

Graphene oxide quantum dots (GOQD) are capable of enhancing the green chemiluminescence (CL) of the system composed of bis (2,4,6-trichlorophenyl) oxalate, hydrogen peroxide and fluorescein (TCPO/H2O2/fluorescein). It was found that 4-nitrophenol (4-NP) causes a further enhancement of the system, and this was exploited to develop a CL detection scheme for 4-NP. The optimum reaction concentrations were established, and under these conditions the calibration plot is linear in the 1.0 to 300 pmol L−1 concentration range, with a 0.3 pmol L−1 detection limit (at 3σ).We assume that CL enhancement is due to energy transfer from GOQD to fluorescein which is promoted by the interaction of 4-NP with the GOQD. The method was applied to the determination of 4-NP in spiked tap water and river water and gave recoveries between 93.4 and 107.9 %, with relative standard deviations of <4.0 %.

Silver nanoparticles enhanced a novel TCPO–H2O2–safranin O chemiluminescence system for determination of 6-mercaptopurine

The present study deals with first attempt to introduce safranin O as the fluorophore for peroxyoxalate chemiluminescence system. The reaction of bis-(2,4,6-trichlorophenyl) oxalate (TCPO) with H2O2 catalyzed by silver nanoparticles can transfer energy to safranin O via the formation of dioxetanedione intermediate and emits orange-red light. The relationship between CL intensity and the concentration of TCPO, fluorophore, hydrogen peroxide and nanocatalyst was investigated. The Ag nanoparticles were synthesized by chemical reduction method and characterized using scanning electron microscopy, particle size analyzer and UV-spectroscopy. Moreover, the system was applied successfully to detect a drug, 6-mercaptopurine (6-MP) in pharmaceuticals. Under optimum conditions, a linear working range for 6-MP concentrations from 5.5×10−7 to 5.5×10−5molL−1 (r>0.9831, n=6) was obtained with a detection limit of 1.6×10−7molL−1. The relative standard deviation for 6 repetitive determinations was less than 3.8% and recoveries of 98% and 103% were obtained.

Optical tomography of fluorophores in dense scattering media based on ultrasound-enhanced chemiluminescence

This letter proposes and demonstrates ultrasound-combined optical imaging in dense scattering media. A peroxyoxalate chemiluminescence system that includes fluorophores to chemically excite the pigment is stimulated by ultrasound irradiation with power of less than 0.14 W/cm2. Using focused ultrasound, the chemiluminescence is selectively spatially enhanced, which leads to imaging of the pigment when embedded in a light-scattering medium via scanning of the focal point. The ultrasonically enhanced intensity of the chemiluminescence depends on the base intensity of the chemiluminescence without the applied ultrasound irradiation, which thereby enables quantitative determination of the fluorophore concentration. The authors demonstrate the potential of this method to resolve chemiluminescent targets in a dense scattering medium that is comparable to biological tissue. An image was acquired of a chemiluminescent target that included indocyanine green as the fluorophore embedded at a depth of 20 mm in an Intralipid-10% 200 ml/l solution scattering medium (the reduced scattering coefficient was estimated to be approximately 1.3 mm−1), indicating the potential for expansion of this technique for use in biological applications.

A lab-on-a-chip device for analysis of amlodipine in biological fluids using peroxyoxalate chemiluminescence system.

A highly sensitive, rapid and economical method for the determination of amlodipine (AM) in biological fluids was developed using a peroxyoxalate chemiluminescence (CL) system in a lab-on-a-chip device. Peroxyoxalate-CL is an indirect type of CL that allows the detection of native fluorophores or compounds derivatized with fluorescent labels. Here, fluorescamine was reacted with AM, and the derivatization product was used in a bis-(2,4,6-trichlorophenyl)oxalate-CL system. Fluorescamine reacts selectively with aliphatic primary amine at neutral or basic pH. As most of the calcium channel blocker and many cardiovascular drugs do not contain primary amine, the developed method is highly selective. The parameters that influenced the CL signal intensity were studied carefully. These included the chip geometry, pH, concentration of reagents used and flow rates. Moreover, we confirmed our previous observation about the effects of imidazole, which is commonly used in the bis-(2,4,6-trichlorophenyl)oxalate-CL system as a catalyst, and found that the signal was significantly improved when imidazole was absent. Under optimized conditions, a calibration curve was obtained with a linear range (10-100 µg/L). The limit of detection was 3 µg/L, while the limit of quantification was 10 µg/L. Finally the method was applied for the determination of AM in biological fluids successfully.

Response surface optimized peroxyoxalate chemiluminescence of octahydro-Schiff base derivative as new luminophor and study of the quenching effect of some cations, amino acids and cholesterol.

We report the first detailed study of the characteristics of an octahydro-Schiff base derivative as a new luminophor in the peroxyoxalate chemiluminescence (POCL) system. The effect of reagents on this new POCL system was investigated. In addition, the response surface methodology was used for evaluating the relative significance of variables in this POCL system, establishing models and determining optimal conditions. The quenching effect of some cations and compounds such as Cu(2+), Fe(3+), Hg(2+), imidazole, histidine and cholesterol on an optimized POCL reaction were studied. The dynamic ranges were up to approximaterly 100 and 175 × 10(-6) M for Cu(2+) and cholesterol respectively. The detection limits were 3.3 × 10(-6) m and 2.58 × 10(-6) m for Cu(2+) and histidine, respectively. In all cases the relative standard deviations were 4-5% (n = 4).

Determination of Hydrogen Peroxide in Abas abad River Water Based on Catalytice effect of TiO2 Nano Particle on Peroxy Oxalate Chemiluminescenc of Triaznyl Dye Derivative

This work is first report showed that supported TiO2 NPs on alumina could act catalytic activity on&#x0D; peroxyoxalate chemiluminescence system. In this work the catalytic effect of supported Titanium&#x0D; dioxide nanoparticles (TiO2 NPs) on the trichloroperoxy oxalate – hydrogen peroxide (PO-CL)&#x0D; reaction is investigated. Supported TiO2 nanoparticles exhibited the better CL catalysis activity than&#x0D; SnO and Carbon nanotubes. Supported TiO2 nanoparticles catalyze the chemiluminescence&#x0D; reaction between TCPO (bis-(2,4,6-trichlorophenyl) oxalate) and H2O2 and produce a strong CL&#x0D; signal in the presence of triazinyl dye derivative as fluorophore. The CL signal intensity was linear&#x0D; with the hydrogen peroxide concentration in the range of 5 to 1000 nmol ml-1 with a detection limit of&#x0D; 1.2 nmol ml-1 and regression coefficient was 0.992 (n=4). The relative standard deviations for&#x0D; measurement of 300 and 500 nmol ml-1 hydrogen peroxide were 2.2 and 3.4%, respectively(n=4).&#x0D; Hydrogen peroxide concentration in river water was 8.7 nmol ml-1 with RSD=5.4%(n=3).

A lab on a chip device for the determination of tranexamic acid using a peroxyoxalate chemiluminescence system

A highly sensitive, rapid and economical method for the determination of tranexamic acid (TA) in pharmaceutical formulations was developed using a peroxyoxalate chemiluminescence system in a lab-on-a-chip device. Peroxyoxalate chemiluminescence (PO-CL) is an indirect type of CL that allows the detection of native fluorophores or compounds derivatised with fluorescent labels. Here, fluorescamine (FA) was reacted with TA and the derivatisation product (FA-TA) was used in a bis-(2,4,6-trichlorophenyl)oxalate (TCPO)-CL system. The parameters that influenced the CL signal intensity were carefully optimised. These included the pH, the concentration of reagents used, the flow rates and the instrumental setup. Additionally, the effects of imidazole, which is commonly used in the TCPO-CL system as a catalyst, and of various surfactants on the CL signal intensity were also investigated. Under optimised conditions, a calibration curve was obtained with a wide linear range (5–900 ng mL−1). The limit of detection (LOD) was 1 ng mL−1, while the limit of quantification (LOQ) was 3 ng mL−1. The method was rapid; approximately 120 runs could be performed per hour, consuming only 0.3 μg of FA and 2.5 μg of TCPO per run. Finally, the method was applied for the determination of TA in pharmaceutical products and was found to be free of interference from other ingredients that are usually present in these preparations.

CAPILLARY ELECTROPHORESIS WITH A CHEMILUMINESCENCE DETECTOR USING THE TWO REACTIONS OF LUMINOL AND PEROXYOXALATE

We investigated capillary electrophoresis (CE) with a chemiluminescence (CL) detector using both CL systems of luminol and peroxyoxalate. Flow- and batch-type CL detection cells were used to analyze model samples, such as isoluminol isothiocyanate (ILITC), fluorescein isothiocyanate (FITC), and proteins labeled with these reagents. CE with the flow-type cell allowed analysis of hemoglobin, FITC, and FITC-labeled hemoglobin. Hemoglobin and FITC were detected with the luminol CL system and peroxyoxalate CL system, respectively, in the CE apparatus. On the other hand, FITC-labeled hemoglobin showed elevated CL with both luminol and peroxyoxalate CL systems. The detection limit of FITC-labeled hemoglobin was ca. 0.6 µM. The CE apparatus with batch-type cell was used to analyze ILITC, FITC, and ILITC-, FITC-, and ILITC/FITC-labeled human serum albumin (HSA). ILITC and ILITC-labeled HSA as well as FITC and FITC-labeled HSA were detected with the luminol CL system and with the peroxyoxalate system, respectively. ILITC/FITC-labeled HSA showed elevated CL with both CL systems.

Dye Doped Eosin Yellowish Silica Nanoparticles as Novel Fluorophore for a Peroxyoxalate Chemiluminescence System

In this work, we report the preparation and characterization of novel dye doped fluorophore Eosin yellowish silica nanoparticles (ESNPs). We synthesized ESNPs by the Stöber method via encapsulation of Eosin Yellowish in silica particles by the condensation of tetraethyl orthosilicate under alkaline condition at room temperature. The resulted ESNPs were characterized by transmission electron microscopy, atomic force microscopy; UV-Visible, fluorescence and Fourier transform infrared spectroscopy. The sizes of the nanoparticles have been found to be 300.0 (±1.0), 400.0 (±1.1) and 500.0 (±5.2) nm depending the reaction conditions under which they were synthesized. Furthermore, because of intense light emission, the ESNPs were used as fluorophore in a peroxyoxalate chemiluminescence system. The effect of solvent and concentrations of necessary reagents, bis(2,4,6-trichlorophenyl)oxalate, sodium salicylate, hydrogen peroxide and the effects of size of the ESNP and temperature on the luminescence efficiency of the system were examined. The activation kinetic parameters of the system were also evaluated from the temperature investigation.

Hypericin from St. John’s Wort (hypericum perforatum) as a novel natural fluorophore for chemiluminescence reaction of bis (2,4,6-trichlorophenyl) oxalate–H2O2–imidazole and quenching effect of some natural lipophilic hydrogen peroxide scavengers

Hypericin (HYP) molecule is a natural photoactive pigment, which plays a role as an effective photoreceptor in some plants of the Hypericum species (the most common of which is Saint John’s Wort) and some insect species. The present work deals with the first attempt to the study of peroxyoxalate chemiluminescence (POCL) system in the presense of HYP as a natural fluorophore. Reaction of bis (2,4,6-trichlorophenyl) oxalate(TCPO)–H2O2–imidazole can transfer energy to a HYP via formation of dioxetane through the chemically initiated electron exchange luminescence (CIEEL) mechanism and can emits a very intense red light. The effects of HYP, hydrogen peroxide, TCPO and imidazole concentrations on kinetic chemiluminescence parameters were also studied. These parameters including rise and fall rate constant for the chemiluminescence burst, theoretical and experimental maximum intensity, theoretical and experimental time to reach maximum intensity and total light yield emission were evaluated by using a pooled intermediate model for a non-linear least-squares curve fitting program, KINFIT. Moreover, quenching effect of two lipophilic natural antioxidant, Quercetin and β-carotene on it system was also investigated. The measurable concentration range of 7×10−6M to 7.5×10−5M of antioxidants were evaluated from the proper Stern–Volmer plots with satisfactory RSD% and corresponding detection limits of 2.2×10−6 and 3.7×10−6 for β-carotene and quercetin respectively.