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121.
ABSTRACT The interaction between phenformin hydrochloride and bovine serum albumin (BSA) was investigated by the methods of chemiluminescence combined with equilibrium dialysis technique. A novel N-bromosuccinimide (NBS)–eosin Y (EY) chemiluminescence (CL) method was established for the determination of phenformin. The mechanism of this chemiluminescence system was proposed. Optimization studies were performed to determine the phenformin. Under the optimal conditions, the CL intensity was linear for a phenformin concentration over the range of 4.6 × 10?8 to 5.0 × 10?5 g/mL. The detection limit was 1.5 × 10?8 g/mL. The data obtained by the present equilibrium dialysis–CL system were analyzed using the Klotz plot and the Scatchard analysis. The results showed that the Klotz plot and the Scatchard plot are linear with good correlation coefficient, indicating that the phenformin has only one type of binding site on BSA. The binding parameters were the number of the binding sites n (1.02) and the estimated association constant K (2.66 × 104 L/mol). The chemiluminescence system combined with equilibrium dialysis developed in this work demonstrated its use for determination of interaction between drug and protein by using relatively simple instrument. 相似文献
122.
Shuangqi Pi Quansong Li Ling Yue Prof. Dr. Ya-Jun Liu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(18):5712-5720
A first-generation pair of chemiluminescent formaldehyde (FA) probes (CFAP540 and CFAP700) was reported recently. CFAP540 and CFAP700, with high selectivity and sensitivity to FA, are, respectively, suitable in cell and in vivo. Experimentalists have confirmed that both probes utilize a general 2-aza-Cope FA-reactive trigger and a chemiluminogenic phenoxydioxetane scaffold. The mechanism and detailed process of CFAP chemiluminescence (CL) remain largely unknown. In the present paper, (time-dependent) density functional theory calculations are performed on the entire reaction process of CFAP540 with FA to produce CL. The calculations elucidated the CL-producing process: FA initiates the decomposition of CFAP540 by dehydration condensation, and a phenoxy 1,2-dioxetane is formed through a series of reactions of aza-Cope rearrangement, hydrolysis of imine, and β-elimination of alkoxyl group. Afterwards, the produced phenoxy 1,2-dioxetane decomposes to produce the m-oxybenzoate derivative in the first singlet state (S1) via two crossings between potential energy surfaces of the ground state (S0) and S1 state. This m-oxybenzoate derivative was assigned as the light emitter of the CFAP540 CL. The CL-producing process and assignment of the light emitter of CFAP700 CL are similar with the corresponding ones of CFAP540. By analyzing the D-π-A architecture of the light emitters of CFAP540 and CFAP700, a series of CFAPs is theoretically designed and a scheme to modulate their CL from visible to near-infrared region is proposed by adjusting the length and structure of the π-bridge. 相似文献
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D. V. Kazakov A. I. Voloshin N. N. Kabal'nova V. V. Shereshovets V. P. Kazakov 《Russian Chemical Bulletin》1996,45(10):2452-2453
Chemiluminescence (CL) was found upon the isomerization of dimethyldioxirane in the gas phase under argon atmosphere. The intensity of CL increases as temperature increases and decreases with time at constant temperature. If Silipor is placed in a cell containing the dimethyldioxirane vapor in argon, the intensity of CL sharply increases (more than 10 times) and then decreases following the exponential law. In all cases tripletly excited methyl acetate is the emitter of chemiluminescence.[/ p]Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 2582–2583, October 1996. 相似文献
128.
碱性条件下,对乙酰氨基酚对鲁米诺-过氧化氢-纳米银化学发光体系有较强的抑制作用,基于此,结合流动注射技术,建立了测定对乙酰氨基酚的新方法。 研究了影响化学发光强度的各种因素,并初步探讨了可能的发光机理。 在最佳实验条件下,对乙酰氨基酚浓度在2.0×10-8~1.0×10-4 mol/L范围内与相对发光强度呈线性关系,检出限(3σ)为4.0×10-9 mol/L。 对1.0×10-7 mol/L的对乙酰氨基酚平行测定9次,相对标准偏差为2.6%。 该法用于片剂中扑热息痛含量的测定,结果令人满意。 相似文献
129.
A new electrogenerated chemiluminescence biosensor was fabricated by immobilizing ECL reagent Ru(bpy)32+ and alcohol dehydrogenase in sol-gel/chitosan/poly(sodium 4-styrene sulfonate) (PSS) organically modified composite material. The component PSS was used to immobilize ECL reagent Ru(bpy)32+ by ion-exchange, while the addition of chitosan was to prevent the cracking of conventional sol-gel-derived glasses and provide biocompatible microenvironment for alcohol dehydrogenase. Such biosensor combined enzymatic selectivity with the sensitivity of ECL detection for quantification of enzyme substrate and it was much simpler than previous double-layer design. The detection limit was 9.3 × 10−6 M for alcohol (S/N = 3) with a linear range from 2.79 × 10−5 to 5.78 × 10−2 M. With ECL detection, the biosensor exhibited wide linear range, high sensitivity and good stability. 相似文献
130.
实验发现盐酸倍他司汀对鲁米诺-高碘酸钾发光体系具有后化学发光作用,并对其作用机理进行了探讨。结合流动注射技术,优化了反应条件,并建立了测定盐酸倍他司汀的新方法。该方法简便、快速、准确,线性范围为2.0×10^-7-4.0×10^-4mol/L(r=0.9975),检出限为1.0×10^-7mol/L;对4.0×10^-5mol/L的盐酸倍他司汀进行了11次平行测定,相对标准偏差为2.9%。方法成功地用于盐酸倍他司汀片中盐酸倍他司汀的测定。 相似文献