Salt additives as activity boosters: a simple strategy to access heterometallic cooperativity in lactide polymerisation

The rational design of conformationally controlled foldable modules can lead to a deeper insight into the conformational space of complex biological molecules where non-covalent interactions such as hydrogen bonding and π-stacking are known to play a pivotal role. Squaramides are known to have excellent hydrogen bonding capabilities and hence, are ideal molecules for designing foldable modules that can mimic the secondary structures of bio-molecules. The π-stacking induced folding of bis-squaraines tethered using aliphatic primary and secondary-diamine linkers of varying length is explored with a simple strategy of invoking small perturbations involving the length linkers and degree of substitution. Solution phase NMR investigations in combination with molecular dynamics simulations suggest that bis-squaraines predominantly exist as extended conformations. Structures elucidated by X-ray crystallography confirmed a variety of folded and extended secondary conformations including hairpin turns and 𝛽-sheets which are determined by the hierarchy of π-stacking relative to N–H···O hydrogen bonds.

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Hierarchy of π-Stacking Determines the Conformational Preference of Bis-Squaraines

10.26434/chemrxiv.13041830 ◽

2020 ◽

Author(s):

Abhishek Singh ◽

Reman K. Singh ◽

G Naresh Patwari

Keyword(s):

Hydrogen Bonding ◽

Rational Design ◽

Biological Molecules ◽

Conformational Space ◽

X Ray Crystallography ◽

Simple Strategy ◽

Induced Folding ◽

Π Stacking ◽

Varying Length ◽

Dynamics Simulations

The rational design of conformationally controlled foldable modules can lead to a deeper insight into the conformational space of complex biological molecules where non-covalent interactions such as hydrogen bonding and π-stacking are known to play a pivotal role. Squaramides are known to have excellent hydrogen bonding capabilities and hence, are ideal molecules for designing foldable modules that can mimic the secondary structures of bio-molecules. The π-stacking induced folding of bis-squaraines tethered using aliphatic primary and secondary-diamine linkers of varying length is explored with a simple strategy of invoking small perturbations involving the length linkers and degree of substitution. Solution phase NMR investigations in combination with molecular dynamics simulations suggest that bis-squaraines predominantly exist as extended conformations. Structures elucidated by X-ray crystallography confirmed a variety of folded and extended secondary conformations including hairpin turns and 𝛽-sheets which are determined by the hierarchy of π-stacking relative to N–H···O hydrogen bonds.

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Synthesis of Functionalized Magnetite Titanium Dioxide Nanocomposite for Removal of Acid Fuchsine Dye

Combinatorial Chemistry & High Throughput Screening ◽

10.2174/1386207321666181019111211 ◽

2018 ◽

Vol 21 (8) ◽

pp. 583-593 ◽

Cited By ~ 1

Author(s):

Sara Rahnama ◽

Shahab Shariati ◽

Faten Divsar

Keyword(s):

Titanium Dioxide ◽

Removal Efficiency ◽

Magnetic Core ◽

Fractional Factorial ◽

Order Kinetic ◽

Sorption Data ◽

Salt Addition ◽

Order Kinetic Model ◽

Pseudo Second Order ◽

Ft Ir

Objective: In this research, a novel magnetite titanium dioxide nanocomposite functionalized by amine groups (Fe3O4@SiO2@TiO2-NH2) was synthesized and its ability for efficient removal of Acid Fuchsine as an anionic dye from aqueous solutions was investigated. Method: The core-shell structure of Fe3O4@SiO2@TiO2 was prepared using Fe3O4 as magnetic core, tetra ethyl orthosilicate as silica and tetra butyl titanate as titanium source for shell. The synthesized nanocomposites (particle size lower than 44 nm) were characterized by FT-IR, XRD, DRS, SEM and TGA instruments. The various experimental parameters affecting dye removal efficiency were investigated and optimized using Taguchi fractional factorial design. Results: The synthesized adsorbent showed the highest removal efficiency of Acid Fuchsine (99 %) at pH= 3.5, without salt addition and during stirring at contact times less than 10 minutes. The study of kinetic models at two concentration levels showed the fast dye sorption on the surface of proposed nanocomposites with pseudo second order kinetic model (R2=1). Also, the fitting of Acid Fuchsine sorption data to Freundlich, Langmuir and Temkin isotherms suggested that Freundlich model gave a better fitting than other models (R2=0.9936, n=2). Conclusion: Good chemical stability, excellent magnetic properties, very fast adsorption kinetics and high removal efficiency make the synthesized nanocomposite as a proper recoverable sorbent for removal of Acid Fuchsine dye from wastewaters.

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Revealing changes in curcumin bioavailability using vitamin C as an enhancer by HPLC-MS/MS

Current Pharmaceutical Analysis ◽

10.2174/1573412916666191220150039 ◽

2019 ◽

Vol 16 ◽

Author(s):

Xufen Dai ◽

Jiaxue Hao ◽

Ying Feng ◽

Jing Wang ◽

Qiannan Li ◽

...

Keyword(s):

Vitamin C ◽

High Performance ◽

Internal Standard ◽

Fold Increase ◽

Rat Plasma ◽

Pharmacokinetic Parameters ◽

Solution Ph ◽

Esi Ms ◽

Simple Strategy ◽

Isolated Compound

Background: Curcumin (CUR), a natural isolated compound from turmeric, has been the promising star in fighting many diseases but the broad application of curcumin has been limited ascribed to low bioavailability. Objective: The aim of this study is to pursue the enhancement of curcumin bioavailability through co-administration of vitamin C. Methods: Such purpose was achieved through the analysis of curcumin pharmacokinetics by high performance liquid chromatography coupled with electrospray ionization - tandem mass spectrometry (HPLC - ESI - MS/MS). The plasma was separated on a C18 reverse phase column using acetonitrile and ammonium formate solution (pH 6.5; 2.0 mM) at 0.8 mL/min. MS/MS detection was carried out in negative mode using mass patterns of m/z 367.0 > 216.7 for curcumin and m/z 265.2 > 223.9 for internal standard (honokiol). Results: Successful application of the proposed method in the pharmacokinetic study presented clear changes in key pharmacokinetic parameters including the growth of AUC (0-t) up to 2.4 times, 2.2-fold increase of Cmax, 2.2-fold loss of CL, and 1.5-fold diminishment of t1/2. Conclusion: We developed an HPLC-ESI-MS/MS method for determination of curcumin in rat plasma and validated the improvement of bioavailability of curcumin through co-administration of vitamin C. We reasoned these changes to the inhibition of lipid peroxidation induced by the use of vitamin C. Such a simple strategy is possible to become an alternative for enhancing curcumin efficiency in practice.

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A simple strategy increases mothers’ knowledge of breastfeeding and improves the breastfeeding rates

Jornal de Pediatria ◽

10.2223/jped.457 ◽

1998 ◽

Vol 74 (5) ◽

pp. 368-76 ◽

Cited By ~ 2

Author(s):

Lulie R.O. Susin ◽

Elsa R. J. Giugliani ◽

Suzane C. Kummer ◽

Marileide Maciel ◽

Ana C. W. Benjamin ◽

...

Keyword(s):

Simple Strategy ◽

Breastfeeding Rates

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A simple strategy based on photobiotin irradiation for the photoelectrochemical immobilization of proteins on electrode surfaces

Materials Science and Engineering C ◽

10.1016/j.msec.2005.10.076 ◽

2006 ◽

Vol 26 (2-3) ◽

pp. 436-441 ◽

Cited By ~ 5

Author(s):

Serge Cosnier ◽

Carmen Molins ◽

Christine Mousty ◽

Bruno Galland ◽

Arielle Lepellec

Keyword(s):

Electrode Surfaces ◽

Simple Strategy

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A Novel Quinoxaline-Rhodamine Conjugate for a Simple and Efficient Detection of Hydrogen Sulphate Ion

Compounds ◽

10.3390/compounds1010004 ◽

2021 ◽

Vol 1 (1) ◽

pp. 29-40

Author(s):

Sutapa Sahu ◽

Yeasin Sikdar ◽

Riya Bag ◽

Dilip K. Maiti ◽

José P. Cerón-Carrasco ◽

...

Keyword(s):

Solid Phase ◽

Detection Limits ◽

Hydrogen Sulfate ◽

Absorption And Emission ◽

Conjugate System ◽

Colorimetric Chemosensor ◽

Simple Strategy ◽

Efficient Detection ◽

Hydrogen Sulphate

This work presents the development of a quinoxaline and rhodamine conjugate system that acts as a colorimetric chemosensor for hydrogen sulfate (HSO4−) ions in methanol media. This sensor has been characterized both theoretically and experimentally. The detection limits for HSO4− are small as 0.71 µM and 3.8 µM for the absorption and emission experiments, respectively. The effectiveness of the probe in recognizing HSO4− both in gel and solid phase is evaluated as well. Thus, this works presents a simple strategy to detect the environmental HSO4− pollutant event at tiny concentrations.

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Cyclometalated iridium–BODIPY ratiometric O2 sensors

Chemical Science ◽

10.1039/c9sc00696f ◽

2019 ◽

Vol 10 (19) ◽

pp. 5124-5132 ◽

Cited By ~ 11

Author(s):

Ku Sun Choung ◽

Karen Marroquin ◽

Thomas S. Teets

Keyword(s):

Molecular Oxygen ◽

Simple Strategy ◽

Ratiometric Sensors

Cyclometalated iridium–BODIPY conjugates are prepared by a simple strategy and are effective ratiometric sensors for molecular oxygen.

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-ADIC -FUNCTIONS FOR ORDINARY FAMILIES ON SYMPLECTIC GROUPS

Journal of the Institute of Mathematics of Jussieu ◽

10.1017/s1474748018000415 ◽

2019 ◽

Vol 19 (4) ◽

pp. 1287-1347 ◽

Cited By ~ 2

Author(s):

Zheng Liu

Keyword(s):

Eisenstein Series ◽

Symplectic Group ◽

Symplectic Groups ◽

Simple Strategy ◽

Doubling Method

We construct the $p$-adic standard $L$-functions for ordinary families of Hecke eigensystems of the symplectic group $\operatorname{Sp}(2n)_{/\mathbb{Q}}$ using the doubling method. We explain a clear and simple strategy of choosing the local sections for the Siegel Eisenstein series on the doubling group $\operatorname{Sp}(4n)_{/\mathbb{Q}}$, which guarantees the nonvanishing of local zeta integrals and allows us to $p$-adically interpolate the restrictions of the Siegel Eisenstein series to $\operatorname{Sp}(2n)_{/\mathbb{Q}}\times \operatorname{Sp}(2n)_{/\mathbb{Q}}$.

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