Standardization and validation of phytometabolites by UHPLC and high-performance thin layer chromatography for rapid quality assessment of ancient ayurvedic medicine,Mahayograj Guggul

Mahayograj Guggul is an ancient ayurvedic medicine, prescribed for various joint disorders like arthritis, gout, and rheumatism. The present research was envisaged to develop a simple, sensitive, and comprehensive analytical method for standardization of Mahayograj Guggul. The analysis was conducted for gallic acid, protocatechuic acid, vanillic acid, cinnamic acid, piperine, guggulsterone-E, and guggulsterone-Z by high-performance thin-layer chromatography, and additionally ferulic acid, ellagic acid, and picroside I by ultra high-performance liquid chromatography. These developed methods were validated as per international guidelines, and were found linear (r² > 0.99), sensitive, precise (relative standard deviation < 5%), and accurate with recovery values (85–105%). The limit of detection and quantification were in the range of 0.11–23.6 and 0.33–71.51 μg/g. Gas chromatography tandem mass spectrometry was used to develop Mahayograj Guggul fingerprinting profile and to identify mid-polar or nonpolar compounds. Proximate analysis was used to ascertain the functional groups present in Mahayograj Guggul. Ultra high-performance liquid chromatography and gas chromatography tandem mass spectrometry were further employed to authenticate quality reproducibility in the active ingredients of Mahayograj Guggul in six commercial batches. Taken together, these analytical methods provide a scientific basis and reference for quality control evaluation of Mahayograj Guggul and similar traditional broad-spectrum formulations.     

Synthesis of multifunctional copolymers of poly(methylphenylsilane) with (R)-N-(1-phenylethyl)methacrylamide,disperse red 1 methacrylate and their optical and photoluminescence properties

Abstract

We report the synthesis and characterization of multifunctional polysilane copolymers containing chiral and azobenzene chromophore as a pendant group. Multifunctional polymers of poly(methylphenylsilane) (PMPS) with (R)-N-(1-phenylethyl)methacrylamide (R-NPEMAM) and disperse red 1 methacrylate (DR1MA) were synthesized in a quartz tube using UV-technique. The molecular weights of such synthesized copolymers were found to be in the order of 10³. The appearance of two glass transition temperatures in DSC indicated that the synthesized copolymers are block copolymers. The electronic absorbance of synthesized polymers was observed at 272?nm (π-π* transition of aromatic ring), 330?nm (σ-σ* transition of Si-Si chain of PMPS) and 475?nm (n-π* with π-π* transition due to azobenzene chromophore of DR1MA unit). The chirality of the synthesized polymer was confirmed through circular dichroism observed at 261?nm. Induced chirality appeared at 330?nm and 470?nm due to the association of the Si-Si chain of PMPS and the presence of azobenzene chromophore of the DR1MA unit respectively. The photoluminescence (PL) properties of the synthesized copolymers (SCDRDM-1B, SCDRDM-2B, and SCDRDM-3B) were observed at 307?nm and 415?nm when excited at 275?nm. The λem was also observed at 415?nm when excited by 325?nm. The multi-emission spectra appeared at 500?nm, 550 and 590?nm are presumed to be due to exciton coupling between azobenzene chromophore of DR1MA, and Si-Si σ-conjugation in association with the aromatic ring of PMPS and chiral unit R-NPEMAM block.     

Oxidation of alcohols using a manganese (II) complex based on a pentakis benzimidazole amide ligand

A pentakis benzimidazole based penta-amide ligand diethylenetriamine—N,N,N′,N′,N″-pentakis(2-methyl benzimidazolyl)penta-amide [GBDTPA] has been synthesized and utilized to prepare Mn (II) complexes of general composition [Mn₂(GBDTPA)X₄], where X is an exogenous anionic ligand (X = Cl⁻, NO₃⁻ and Br⁻). The oxidation of alcohols has been investigated using [Mn₂(GBDTPA)Cl₄] as the catalyst and TBHP as an alternate source of oxygen. The respective aldehydic products have been isolated and characterized by ¹H NMR.     

Ultrafast strain engineering in complex oxide heterostructures

We report on ultrafast optical experiments in which femtosecond midinfrared radiation is used to excite the lattice of complex oxide heterostructures. By tuning the excitation energy to a vibrational mode of the substrate, a long-lived five-order-of-magnitude increase of the electrical conductivity of NdNiO(3) epitaxial thin films is observed as a structural distortion propagates across the interface. Vibrational excitation, extended here to a wide class of heterostructures and interfaces, may be conducive to new strategies for electronic phase control at THz repetition rates.     

Studies on Intermolecular Interactions in Liquid Mixtures of Alkoxyalkanols and Branched Alcohols by Volumetric and Acoustic Measurements at Different Temperatures

Densities and speeds of sound for binary mixtures of diethylene glycol monomethyl ether and triethylene glycol monomethyl ether with 3-methyl-1-butanol and 2-methyl-2-butanol were measured at 288.15, 298.15 and 308.15 K, over the entire range of compositions at atmospheric pressure, using an Anton Paar DSA 5000 density meter. The experimental densities and speeds of sound have been used to calculate excess molar volumes and excess molar isentropic compressibilities. The speed of sound data are compared with theoretical speeds of sound calculated using several approaches.     

Polyfluorophenylamino Germanes and Their Titanium (IV) Chloride Adducts

Disproportionation reactions between (CF ₃ CH ₂ O) ₃ GeNHC ₆ H _{5 ? n} F _n and TiCl ₄ in petroleum ether (40?60°C) at 0° to ?10°C give (CF ₃ CH ₂ O) ₂ Ge(NHC ₆ H _{5 ? n} F _n ) ₂ ^.2TiCl ₄ and (CF ₃ CH ₂ O)Ge(NHC ₆ H _{5 ? n} F _n ) ₃ ^. 2TiCl ₄ adducts. However, complete disproportionation of (CF ₃ CH ₂ O) ₃ Ge(NHC ₆ H _{5 ? n} F _n ) (n = 1,2) occurs at ?55 to ?60°C to give Ge(NHC ₆ H _{5 ? n} F _n ) ₄ ^.3TiCl ₄ . These complexes give double adducts on reactions with CH ₃ NO ₂ and CH ₃ CN. All the products are characterized by elemental analyses and IR, ¹ H, and ¹⁹ F NMR spectroscopy. A comparative disproportionation of the germanamines and analogous silanamines is discussed.     

Copper(II) complexes of new biomimetic polydentate amide ligands: a spectroscopic study

Complexes of Cu(II) with N,N'-bis(3-carboxy-1-oxopropanyl)-1,2-ethylenediamine(C(10)H(16)N(2)O(6),L(1)), N,N'-bis(3-carboxy-1-oxopropanyl)-1,2-phenylenediamine(C(14)H(16)N(2)O(6),L(2)), N,N'-bis(2-carboxy-1-oxophenelenyl)-1,2-phenylenediamine(C(22)H(16)N(2)O(6),L(3)) and N,N'-bis(3-carboxy-1-oxoprop-2-enyl)-1,2-phenylenediamine(C(14)H(12)N(2)O(6),L(4)) have been prepared and characterised by elemental analyses, vibrational spectra, magnetic susceptibility measurements, ligand field spectra, EPR spectra, thermal studies and X-ray diffraction spectra. Vibrational spectra indicate coordination of amide and carboxylate oxygens of the ligands giving a MO(4) square planar chromophore. Ligand field and EPR spectra support square planar geometry around Cu(II). [Cu(L(1))] complex has the maximum activation energy and [Cu(L(3))] complex has the minimum activation energy.     

Metformin and Biguanide Complexes of Isothiocyanatosilane

Abstract

The preparation of neutral and ionic silicon–nitrogen complexes has been achieved by a single-step room temperature reaction by using isothiocyanatosilanes and metformin/biguanide ligands. These bidentate ligands coordinate to the silicon atom in a neutral as well as a deprotonated form to yield two different types of complexes. The resulting complexes have been characterized by the physical and spectroscopic techniques.     

Band gap narrowing and fluorescence properties of nickel doped SnO2 nanoparticles

Nickel-doped tin oxide nanoparticles (sub-5 nm size) with intense fluorescence emission behavior have been synthesized by sol-gel route. The structural and compositional analysis has been carried out by using XRD, TEM, FESEM and EDAX. The optical absorbance spectra indicate a band gap narrowing effect and it was found to increase with the increase in nickel concentration. The band gap narrowing at low dopant concentration (<5%) can be assigned to SnO₂−SnO_2−x alloying effect and for higher doping it may be due to the formation of defect sub-bands below the conduction band.