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Here, sulfonated polyaniline (SPAN) was decorated on the surface of copper-based metal organic frame (HKUST-1) and the composite was functionalized by luminol to construct a chemiluminescence (CL) hybrids (SPAN/HKUST-1@Luminol). The as-prepared SPAN/HKUST-1@Luminol demonstrated a great dispersion and stability performance in aqueous solution. Moreover, the resultant SPAN/HKUST-1@Luminol hybrids exhibited extremely strong CL properties, and the CL quantum yield was 136 times higher than that of luminol. In particular, it exhibited outstanding CL activity not only under alkaline conditions, but also under neutral conditions. The sensitive response of the hybrid to hydrogen peroxide was used to construct CL methods for the detection of hydrogen peroxide at a wide range of pH, with the detection limit of 60 nM at a neutral condition and 25 pM at alkaline condition. Due to strong and stable signal of the SPAN/HKUST-1@Luminol, the CL method provides a viable tool for determination of H 2 O 2 in biological systems and enabled the monitoring of stimulated production of H 2 O 2 released by living cells., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)

A novel [Co(L)(H 2 O) 2 ] (1) was obtained by hydrothermal method and it exhibited a 1D chain with exposed carboxyl groups, the unique coordination mode made it have unusual physical and chemical stability. Meanwhile, 1 showed peroxidase-like and weak oxidase-like activity. 1 as a peroxidase mimic enzyme had an excellent affinity for the substrates luminol and H 2 O 2 . Compared with HRP, 1 had catalytic activity in a wide pH range and showed the best catalytic activity at pH 7.4. Meanwhile, the catalysis process of 1 was reversible and recyclable, and the catalytic activity remained stable after different pH and temperatures and long-time storage. Based on the inhibition of glutathione on luminol-H 2 O 2 -MOF 1 chemiluminescence signal, a chemiluminescence method for the determination of glutathione has been proposed with high sensitivity and selectivity and had been applied for detecting glutathione in cell lysate with satisfactory results., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Luminol-nitrogen doped graphene quantum dot (luminol-NGQDs) nanocomposite was synthesized and a novel electrochemiluminescence resonance energy transfer (ECL-RET) process occurred between luminol as the donor and NGQDs as the acceptor in the composite. This ECL-RET effect helped luminol-NGQDs composite produced an anodic ECL signal without coreactants. The ECL-RET mechanism was also studied based on the fluorescence spectra, the ultraviolet-visible absorption spectra and the electrochemiluminescence (ECL) spectra. Based on the significant sensitization effect of hydrogen peroxide on luminol-NGQDs ECL signal, an ECL method for the sensitive determination of hydrogen peroxide was established and then applied to the detection of hydrogen peroxide in water samples., (Copyright © 2018 Elsevier B.V. All rights reserved.)

A strong post chemiluminescence (PCL) phenomenon was observed when ammonium was injected into the reaction mixture after the finish of CL reaction of N-bromosuccinimide (NBS) and dichlorofluorescein. Based on this, a sensitive flow injection PCL method was established for the determination of ammonium. The possible CL mechanism of the reaction was proposed based on a series of experiments. The PCL intensity responded linearly to the concentration of ammonium in the range 3.0 × 10(-11) -1.0 × 10(-7) g mL(-1) with a detection limit of 1 × 10(-11) g mL(-1). The relative standard deviation (R.S.D.) was 1.4% for 1.0 × 10(-9) g mL(-1) ammonium (n=11). This method had been applied to the determination of ammonium in samples of mineral water, tap water and river water., (Copyright © 2011 Elsevier B.V. All rights reserved.)

LYG-202 is a newly synthesized flavonoid with a piperazine substitution. We investigated the antitumor effect of LYG-202 in vivo and in vitro. We show that, LYG-202 significantly decreases tumor growth in mice inoculated with S180 sarcoma cells, compared with the control group. Meanwhile, the viabilities of various kinds of tumor cells were inhibited by LYG-202 with IC(50) values in the range of 4.80 to 27.70 microM. Then apoptosis induced by LYG-202 in HepG2 cells was characterized by DAPI staining and Annexin V/PI double staining and degradation of PARP was observed. Activation of the caspase cascade for both the extrinsic and intrinsic pathways was demonstrated, including caspase-8, -9, and -3. The results also showed that the expression of Bcl-2 protein decreased whereas that of Bax protein increased, leading to an increase of the Bax/Bcl-2 ratio. Our results demonstrated that LYG-202 exhibited strong antitumor effect in vivo and in vitro, involving with apoptosis induction.

A post-chemiluminescence (PCL) phenomenon was observed when pentoxyverine citrate solution was injected into the reaction mixture after the finish of chemiluminescence (CL) reaction of N-chlorosuccinimide (NCS) and alkaline dichlorofluorescein. The possible reaction mechanism was proposed based on the studies of the CL kinetic characteristics, the CL spectra and the fluorescence spectra of some related substances. Based on the PCL reaction, a rapid and sensitive method for the determination of pentoxyverine citrate was established. The linear response range of this method was from 6.0x10(-9) to 1.0x10(-6)gmL(-1) with a linear correlation coefficient of 0.9998. The relative standard deviation for 2.0x10(-8)gmL(-1) pentoxyverine citrate was 2.1% (n=11). The detection limit was 9x10(-10)gmL(-1). This method has been applied to the determination of pentoxyverine citrate in human plasma and pharmaceutical samples with the satisfactory results.

We recently established that asparanin A, a steroidal saponin extracted from Asparagus officinalis L., is an active cytotoxic component. The molecular mechanisms by which asparanin A exerts its cytotoxic activity are currently unknown. In this study, we show that asparanin A induces G(2)/M phase arrest and apoptosis in human hepatocellular carcinoma HepG2 cells. Following treatment of HepG2 cells with asparanin A, cell cycle-related proteins such as cyclin A, Cdk1 and Cdk4 were down-regulated, while p21(WAF1/Cip1) and p-Cdk1 (Thr14/Tyr15) were up-regulated. Additionally, we observed poly (ADP-ribose) polymerase (PARP) cleavage and activation of caspase-3, caspase-8 and caspase-9. The expression ratio of Bax/Bcl-2 was increased in the treated cells, where Bax was also up-regulated. We also found that the expression of p53, a modulator of p21(WAF1/Cip1) and Bax, was not affected in asparanin A-treated cells. Collectively, our findings demonstrate that asparanin A induces cell cycle arrest and triggers apoptosis via a p53-independent manner in HepG2 cells. These data indicate that asparanin A shows promise as a preventive and/or therapeutic agent against human hepatoma.

Oroxylin A is a flavonoid that is found in the roots of Scutellaria baicalensis Georgi. Here, we investigated the antitumor effect of oroxylin A in human cervical cancer HeLa cell line in vitro and in vivo. We found that after inoculated with the HeLa cells the mice treated with oroxylin A showed a significant decrease of tumor volumes and tumor weight compared with the control. Meanwhile, the growth inhibition of oroxylin A on HeLa cells were observed by MTT assay and the value of IC(50) was 19.4+/-0.7 microM after treatment for 48h. Upon our previous research, the inhibition by oroxylin A might be through apoptosis. Then apoptosis induced by oroxylin A in HeLa cells was characterized by DAPI staining and Annexin V/PI double staining, and degradation of PARP (poly-ADP-ribose polymerase) was both found in HeLa cells and tumor tissue. Next, activation of the caspase cascade for both the extrinsic and intrinsic pathways were demonstrated in vivo and in vitro, including caspase-8, -9 and -3. We also found that the expression of Bcl-2 protein decreased, which leading to an increase of the Bax/Bcl-2 ratio. Our results showed that oroxylin A exhibited strong antitumor effect in HeLa cell line and apoptosis induction involved in it.

A simple, sensitive and selective chemiluminescence (CL) method was developed for the direct determination of aluminum (Al). This method is based on that the weak CL of cerium (IV)-calcein can be greatly enhanced by Al(III). The calibration curve was linear over the range 2.0 x 10(-10) to 4.0 x 10(-8)g mL(-1) with a detection limit of 8 x 10(-11)g mL(-1) (3sigma). The R.S.D. was 2.5% by 11 replicated determinations of 1.0 x 10(-9)g mL(-1) Al(III). The proposed method has been used to determine the concentration of Al(III) in real water samples with satisfactory results. The mechanism of the CL reaction was also discussed.

Calcein was found to be able to use as chemiluminescence reagent and post-chemiluminescence was observed when fenfluramine was injected into the mixture after the CL reaction of calcein-potassium permanganate. Based on this phenomenon, a flow injection CL method was established for the determination of fenfluramine. The possible CL mechanism was proposed. The CL intensity was correlated linearly with the concentration of fenfluramine over the range of 1.0 x 10(-7) to 6.0 x 10(-6) g mL(-1) and the detection limit was 6 x 10(-8) g mL(-1). The relative standard deviation was 2.2% for 5.0 x 10(-7) g mL(-1) fenfluramine (n=11). This method was applied to the determination of fenfluramine in weight-reducing tonic successfully.

A soluble Mn (IV)-formaldehyde-indomethacin chemiluminescence system was found. Using a synthesized indomethacin MIP as recognition material and soluble Mn (IV)-formaldehyde-indomethacin as detection system, a new molecule imprinted-chemiluminesence method of determination of indomethacin was established. The response range of this method was between 1.0x10(-7) and 1.0x10(-5)g/mL with a linear correlation coefficient of 0.994. The detection limit was 4x10(-8)g/mL. The relative standard deviation for 5.0x10(-7)g/mL of indomethacin solution was 3.1% (n=7).