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排序方式: 共有325条查询结果,搜索用时 31 毫秒
1.
Veenu Bala Yashpal S. Chhonker Richard L. Sleightholm Ayrianne J. Crawford Michael A. Hollingsworth Daryl J. Murry 《Biomedical chromatography : BMC》2020,34(8):e4859
A rapid, selective, and sensitive liquid chromatography coupled with tandem mass spectrometry (MS/MS) method was developed and validated for the quantitation of the novel CDK5 inhibitor ‘20–223' in mouse plasma. Separation of analytes was achieved by a reverse-phase ACE Excel C18 column (1.7 μm, 100 × 2.1 mm) with gradient elution using 0.1% formic acid (FA) in methanol and 0.1% FA as the mobile phase. Analytes were monitored by MS/MS with an electrospray ionization source in the positive multiple reaction monitoring mode. The MS/MS response was linear over the concentration range 0.2–500 ng/mL for 20–223. The within- and between-batch precision were within the acceptable limits as per Food and Drug Administration guidelines. The validated method was successfully applied to plasma protein binding and in vitro metabolism studies. Compound 20–223 was highly bound to mouse plasma proteins (>98% bound). Utilizing mouse S9 fractions, in vitro intrinsic clearance (CLint) was 24.68 ± 0.99 μL/min/mg protein. A total of 12 phase I and II metabolites were identified with hydroxylation found to be the major metabolic pathway. The validate method required a low sample volume, was linear from 0.2 to 500 ng/mL, and had acceptable accuracy and precision. 相似文献
2.
Bishnu P. Biswal Sreeramulu Valligatla Mingchao Wang Tanmay Banerjee Nabil A. Saad Bala Murali Krishna Mariserla Naisa Chandrasekhar Daniel Becker Matthew Addicoat Irena Senkovska Reinhard Berger D. Narayana Rao Stefan Kaskel Xinliang Feng 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(21):6970-6974
Covalent organic frameworks (COFs) have garnered immense scientific interest among porous materials because of their structural tunability and diverse properties. However, the response of such materials toward laser‐induced nonlinear optical (NLO) applications is hardly understood and demands prompt attention. Three novel regioregular porphyrin (Por)‐based porous COFs—Por‐COF‐HH and its dual metalated congeners Por‐COF‐ZnCu and Por‐COF‐ZnNi—have been prepared and present excellent NLO properties. Notably, intensity‐dependent NLO switching behavior was observed for these Por‐COFs, which is highly desirable for optical switching and optical limiting devices. Moreover, the efficient π‐conjugation and charge‐transfer transition in ZnCu‐Por‐COF enabled a high nonlinear absorption coefficient (β=4470 cm/GW) and figure of merit (FOM=σ1/σo, 3565) value compared to other state‐of‐the‐art materials, including molecular porphyrins (β≈100–400 cm/GW), metal–organic frameworks (MOFs; β≈0.3–0.5 cm/GW), and graphene (β=900 cm/GW). 相似文献
3.
Surbhi Grewal Pravesh Kumar Dr. Saonli Roy Dr. Indu Bala Dr. Chitranjan Sah Dr. Santanu Kumar Pal Dr. Sugumar Venkataramani 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(19):e202104602
Two tripodal C3-symmetric photoswitchable molecular systems T1 and T2 are reported that have extended conjugation at external and internal positions using an acryl group. The influence of the extended π-bonds in their absorption properties, thermal relaxation of the photoisomers and their propensities in forming supramolecular self-assemblies have been explored through spectroscopy, and microscopic studies. In particular, the investigations on the self-assembly have been carried out using scanning electron microscopy (SEM), transmission electron microscopy (TEM), polarized optical microscopy (POM), X-ray diffraction studies (XRD) and atomic force microscopy (AFM). Remarkably, the position of the acryl group influences the behaviour of the two target molecules in supramolecular assembly, and also in the formation of photoresponsive organic hydrogels or microcrystals. 相似文献
4.
Chetan Bhadaliya Bala Krishna Panigrahy Dipanjan Goswami Sovan Maiti Sanjay Jagannath Gurule Arshad H. Khuroo 《Biomedical chromatography : BMC》2022,36(4):e5337
A selective, highly sensitive, precise, and novel bioanalytical method has been developed and validated to quantify sinococuline, an active constituent present in the phytopharmaceutical drug product containing Cocculus hirsutus plant extract, in vivo. Chromatographic separation was achieved on a Luna Omega Polar-C18 bonded analytical column maintained at 45°C. The isocratic mobile phase consisted of methanol and ammonium formate buffer (60:40, v/v) at acidic pH with a low flow rate of 0.250 mL/min. Detection was performed on an API 4000 mass spectrometer using electrospray ionization in positive polarity and multiple reaction monitoring mode to achieve a lower limit of quantification of 1.50 ng/mL. Excellent accuracy and precision were obtained after extracting the analyte from plasma samples using a chemical analogue as an internal standard in the absence of an isotope-labeled compound. The extraction efficacy was evidenced from recovery study, and the analyte was found to be stable in plasma. Validation study demonstrated linearity with coefficient of correlation, r ≥ 0.99, and minimal matrix effect. This bioanalytical method was successfully applied to evaluate pharmacokinetic parameters of sinococuline from a phase I clinical trial of an aqueous extract of C. hirsutus in healthy human volunteers. 相似文献
5.
Sharoni Gupta Chetna Ameta Pinki Bala Punjabi 《Journal of heterocyclic chemistry》2020,57(6):2410-2427
In the present paper, a novel and benign protocol for microwave enhanced one pot syntheses of 2,3-dihydro-1,5 benzodiazepine derivatives from substituted acetophenones, aryl-aldehydes and o-phenylene diamine using heterogeneous calcium ferrite/graphene oxide (CF/GO) nanocomposite has been reported. The catalyst was prepared by ultrasonication method and characterized by spectral and analytical techniques. The CF/GO nanocomposite was employed for environmentally benign synthesis of 2,3-dihydro-1,5 benzodiazepines. The synthesized benzodiazepine derivatives were screened for their antimicrobial activities against various bacteria and fungi. The present synthetic strategy offered several advantages such as excellent yields in short span of time, simple modus operandi, ease of isolation and purification of products, simple recovery and reusability of the catalyst. A tentative mechanism for synthesis of 2,3-dihydro-1,5 benzodiazepine using CF/GO nanocatalyst has also been proposed. 相似文献
6.
Bala Ritu Das Debabrata Karanveer Naskar Nabanita Lahiri Susanta 《Journal of Radioanalytical and Nuclear Chemistry》2022,331(6):2561-2572
Journal of Radioanalytical and Nuclear Chemistry - Natural radionuclide levels are studied in alluvial sediments upto the depth of 900 cm. Eighteen profiles are selected from agricultural... 相似文献
7.
Eleven constituents were characterised by gas chromatography–mass spectrometry analysis, and five molecules were isolated using column chromatography. The in vitro study of the extract and isolated molecules against KB and SiHa cell lines revealed oleanolic acid (1) and oleic acid (2) as potent cytotoxic molecules with potential anticancer activity. The IC50 values of n-hexane extract (CPHF), oleanolic acid (1) and oleic acid (2) were >300, 56.08 and 70.7 μg/mL (μM), respectively, against KB cell lines and >300, 47.24 and 80.2 μg/mL (μM), respectively, against SiHa cell lines. 相似文献
8.
Janovszky Dora Sveda Maria Sycheva Anna Kristaly Ferenc Zámborszky Ferenc Koziel Tomasz Bala Piotr Czel Gyorgy Kaptay George 《Journal of Thermal Analysis and Calorimetry》2022,147(13):7141-7157
Journal of Thermal Analysis and Calorimetry - A remarkable number of scientific papers are available in the literature about the bulk amorphous alloys and metallic glasses. Today, DSC is an... 相似文献
9.
Akkaraboyina Lakshmi Lavanya K. Gowri Bala Kumari K. R. S. Prasad Pradeep Kumar Brahman 《Electroanalysis》2021,33(4):1096-1106
The development and fabrication of a simple, portable, and sensitive detection tool to precisely monitor nitrite level is of growing importance in electrochemistry research, given the strong interest in the protection of drinking water quality, treatment of wastewater, food production, and control of remediation processes. This work describes the fabrication of a simple, cost-effective, pen-type electrochemical sensor based on bimetallic gold and tungsten nanoparticles electrochemically decorated on graphene-chitosan modified pencil graphite electrode (PGE) for the trace detection of nitrite in real samples. The prepared nanocomposite was characterized using XRD, SEM, and EDS. The electrochemical behavior of the sensor was evaluated by cyclic voltammetry (CV) and impedance electrochemical spectroscopy (EIS). Results revealed that the proposed sensor displayed excellent electrocatalytic activity towards electro-oxidation of nitrite with an irreversible redox reaction. The AuNPs-WNPs@Gr-Chi/PGE sensor exhibited excellent analytical performance with a wide linear range from 10 to 250 μM towards nitrite. The LOD and LOQ were calculated to be 0.12 μM and 0.44 μM, respectively. The designed electrochemical sensor was successfully applied for the detection of nitrite in water, milk, and natural fruit juice samples. 相似文献
10.
Akkaraboyina Lakshmi Lavanya K. Gowri Bala Kumari K. R. S. Prasad Pradeep Kumar Brahman 《Electroanalysis》2021,33(3):591-600
In this work, an economically viable, very low cost, indigenous, ubiquitously available electrochemical sensor based on bimetallic nickel and tungsten nanoparticles modified pencil graphite electrode (NiNP-WNP@PGE) was fabricated for the sensitive and selective detection of bisphenol A (BPA). The NiNP-WNP@PGE sensor was prepared by a facile electrochemical one step co-deposition method. The prepared nanocomposite was morphologically characterized by scanning electron microscopy (SEM), energy dispersive X-ray (EDX), X-ray diffraction (XRD), electrochemically by cyclic voltammetry (CV), and electrochemical impedance spectroscopy (EIS). The proposed sensor displayed high electrocatalytic activity towards electro-oxidation of BPA with one irreversible peak. The fabricated sensor displayed a wide detection window between 0.025 μM and 250 μM with a limit of detection of 0.012 μM. PGE sensor was successfully engaged for the detection of BPA in bottled water, biological, and baby glass samples. 相似文献