Hexaphenylbenzene-based fluorescent aggregates for detection of zinc and pyrophosphate ions in aqueous media: tunable self-assembly behaviour and construction of a logic device

2017 ◽  
Vol 41 (12) ◽  
pp. 4806-4813 ◽  
Author(s):  
Subhamay Pramanik ◽  
Vandana Bhalla ◽  
Manoj Kumar
Keyword(s):  
Self Assembly ◽  
Aqueous Media ◽  
Logic Device

The aggregates of HPB derivative 7 exhibited “on–on” response towards Zn2+ ions and this in situ prepared 7-Zn2+ ensemble was utilized as a “not quenched” probe for detection of PPi ions in aqueous media.

Preparation of L-Tryptophan Imprinted Polymer Microspheres in Aqueous Media by In Situ Grafting on Surface

2011 ◽  
Vol 306-307 ◽  
pp. 1658-1662
Author(s):  
Jie Ding ◽  
Shuang Shuang Chen ◽  
Xiao Li ◽  
Xiao Guang Ying ◽  
Shang Feng Jiang ◽  
...  
Keyword(s):  
Self Assembly ◽  
Aqueous Media ◽  
Polymer Microspheres ◽  
Imprinted Polymer ◽  
Adsorption Models ◽  
Functional Monomers ◽  
Isotherm Equation ◽  
Porous Microspheres ◽  
Langmuir Isotherm Equation

In situ grafting on surface was developed to modify porous microspheres. Functional monomers were grafted onto the porous microspheres. The grafting yield was up to 54.6%. The self-assembly of functional monomer and L-tryptophan molecules was verified by UV spectrometry. The surface imprinted polymer microspheres (SMIPs) were synthesized based on the in situ grafting on surface. The competitive binding experiments were carried out to assess the recognition. The results showed good selectivity of the SMIPs towards target molecule. Langmuir and Freundlich adsorption models were applied to description of the experimental adsorption isotherm. The analysis suggested that the adsorbing behavior of SMIPs was in agreement with Langmuir isotherm equation.

Bioinspired Catalysis: Self-Assembly of a Protein and DNA as a Catalyst for the Aldol Reaction in Aqueous Media

Synlett ◽  
2017 ◽  
Vol 29 (05) ◽  
pp. 560-565 ◽  
Author(s):  
Guangxun Li ◽  
Zhuo Tang ◽  
Hongxin Liu ◽  
Ying-wei Wang ◽  
Shiqi Zhang
Keyword(s):  
Catalytic System ◽  
Electrostatic Interaction ◽  
Self Assembly ◽  
Aldol Reaction ◽  
Aqueous Media ◽  
Aldol Reactions ◽  
Mild Conditions ◽  
Self Assembling ◽  
High Yields

An interesting bioinspired catalyst formed from readily available DNA and a protein through electrostatic interaction in situ proved to be efficient in catalyzing aldol reactions under mild conditions in water. By using a self-assembling catalytic system formed from protamine and DNA, aldol adducts were obtained with high yields and moderate enantioselectivities. Preliminary experiments demonstrated that the chirality of the DNA could be effectively transferred to the reaction product through the bound molecules or proteins.

In vitro and in vivo polysaccharides assembly: ultrastructural and cytochemical study of growing plant cell wall components.

1978 ◽  
Vol 36 (2) ◽  
pp. 434-435
Author(s):  
D. Reis ◽  
B. Vian ◽  
J. C. Roland
Keyword(s):  
Cell Wall ◽  
Self Assembly ◽  
Plant Cell Wall ◽  
Higher Plants ◽  
Three Dimensional ◽  
Cytochemical Study ◽  
Wall Components

Wall morphogenesis in higher plants is a problem still open to controversy. Until now the possibility of a transmembrane control and the involvement of microtubules were mostly envisaged. Self-assembly processes have been observed in the case of walls of Chlamydomonas and bacteria. Spontaneous gelling interactions between xanthan and galactomannan from Ceratonia have been analyzed very recently. The present work provides indications that some processes of spontaneous aggregation could occur in higher plants during the formation and expansion of cell wall.Observations were performed on hypocotyl of mung bean (Phaseolus aureus) for which growth characteristics and wall composition have been previously defined.In situ, the walls of actively growing cells (primary walls) show an ordered three-dimensional organization (fig. 1). The wall is typically polylamellate with multifibrillar layers alternately transverse and longitudinal. Between these layers intermediate strata exist in which the orientation of microfibrils progressively rotates. Thus a progressive change in the morphogenetic activity occurs.

Probing the Dynamic Self-Assembly Behaviour of Photoswitchable Wormlike Micelles in Real Time

2018 ◽  
Author(s):  
Elaine A. Kelly ◽  
Judith E. Houston ◽  
Rachel Evans
Keyword(s):  
Real Time ◽  
Absorption Spectroscopy ◽  
Self Assembly ◽  
Uv Light ◽  
Wormlike Micelles ◽  
Tetraethylene Glycol ◽  
Light Illumination ◽  
First Time ◽  
Dependent Processes

Understanding the dynamic self-assembly behaviour of azobenzene photosurfactants (AzoPS) is crucial to advance their use in controlled release applications such as<i></i>drug delivery and micellar catalysis. Currently, their behaviour in the equilibrium <i>cis-</i>and <i>trans</i>-photostationary states is more widely understood than during the photoisomerisation process itself. Here, we investigate the time-dependent self-assembly of the different photoisomers of a model neutral AzoPS, <a>tetraethylene glycol mono(4′,4-octyloxy,octyl-azobenzene) </a>(C<sub>8</sub>AzoOC<sub>8</sub>E<sub>4</sub>) using small-angle neutron scattering (SANS). We show that the incorporation of <i>in-situ</i>UV-Vis absorption spectroscopy with SANS allows the scattering profile, and hence micelle shape, to be correlated with the extent of photoisomerisation in real-time. It was observed that C<sub>8</sub>AzoOC<sub>8</sub>E<sub>4</sub>could switch between wormlike micelles (<i>trans</i>native state) and fractal aggregates (under UV light), with changes in the self-assembled structure arising concurrently with changes in the absorption spectrum. Wormlike micelles could be recovered within 60 seconds of blue light illumination. To the best of our knowledge, this is the first time the degree of AzoPS photoisomerisation has been tracked <i>in</i><i>-situ</i>through combined UV-Vis absorption spectroscopy-SANS measurements. This technique could be widely used to gain mechanistic and kinetic insights into light-dependent processes that are reliant on self-assembly.

In situ Time-Resolved Small-Angle X-ray Scattering Reveals the Formation Kinetics of Polyelectrolyte Complex Micelles

2019 ◽  
Author(s):  
Hao Wu ◽  
Jeffrey Ting ◽  
Siqi Meng ◽  
Matthew Tirrell
Keyword(s):  
Small Angle ◽  
Self Assembly ◽  
Electrostatic Interactions ◽  
Polyelectrolyte Complex ◽  
Time Resolved ◽  
X Ray ◽  
X Ray Scattering ◽  
Kinetics Of ◽  
Ray Scattering

We have directly observed the <i>in situ</i> self-assembly kinetics of polyelectrolyte complex (PEC) micelles by synchrotron time-resolved small-angle X-ray scattering, equipped with a stopped-flow device that provides millisecond temporal resolution. This work has elucidated one general kinetic pathway for the process of PEC micelle formation, which provides useful physical insights for increasing our fundamental understanding of complexation and self-assembly dynamics driven by electrostatic interactions that occur on ultrafast timescales.

scholarly journals Development of In Situ Self-Assembly Nanoparticles to Encapsulate Lopinavir and Ritonavir for Long-Acting Subcutaneous Injection

Pharmaceutics ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 904
Author(s):  
Irin Tanaudommongkon ◽  
Asama Tanaudommongkon ◽  
Xiaowei Dong
Keyword(s):  
Sustained Release ◽  
Trough Concentration ◽  
Self Assembly ◽  
Subcutaneous Injection ◽  
Drug Loading ◽  
Entrapment Efficiency ◽  
Long Acting

Most antiretroviral medications for human immunodeficiency virus treatment and prevention require high levels of patient adherence, such that medications need to be administered daily without missing doses. Here, a long-acting subcutaneous injection of lopinavir (LPV) in combination with ritonavir (RTV) using in situ self-assembly nanoparticles (ISNPs) was developed to potentially overcome adherence barriers. The ISNP approach can improve the pharmacokinetic profiles of the drugs. The ISNPs were characterized in terms of particle size, drug entrapment efficiency, drug loading, in vitro release study, and in vivo pharmacokinetic study. LPV/RTV ISNPs were 167.8 nm in size, with a polydispersity index of less than 0.35. The entrapment efficiency was over 98% for both LPV and RTV, with drug loadings of 25% LPV and 6.3% RTV. A slow release rate of LPV was observed at about 20% on day 5, followed by a sustained release beyond 14 days. RTV released faster than LPV in the first 5 days and slower than LPV thereafter. LPV trough concentration remained above 160 ng/mL and RTV trough concentration was above 50 ng/mL after 6 days with one subcutaneous injection. Overall, the ISNP-based LPV/RTV injection showed sustained release profiles in both in vitro and in vivo studies.

Plasmonics tunable Ag-coated gold nanorods arrays as reusable SERS substrates for multiplexed antibiotics detection

2021 ◽  
Author(s):  
Xiaoya Peng ◽  
Dan Li ◽  
Yuanting Li ◽  
Haibo Xing ◽  
Wei Deng
Keyword(s):  
Gold Nanorods ◽  
Self Assembly ◽  
Aqueous Media ◽  
Antibiotic Residues ◽  
Sers Substrates ◽  
Antibiotics Detection ◽  
Robust Strategies

Antibiotic contaminants in aqueous media pose serious threat to human and ecological environments. Therefore, it is necessary to develop robust strategies to detect antibiotic residues. For this purpose, a self-assembly...

Sign in / Sign up

Export Citation Format

Share Document