A multifunctional amphiphilic polymer as a platform for surface-functionalizing metallic and other inorganic nanostructures

2014 ◽  
Vol 175 ◽  
pp. 137-151 ◽  
Author(s):  
Wentao Wang ◽  
Fadi Aldeek ◽  
Xin Ji ◽  
Birong Zeng ◽  
Hedi Mattoussi
Keyword(s):  
Colloidal Stability ◽  
Addition Reaction ◽  
Biologically Active ◽  
Metal Nanostructures ◽  
Organic Media ◽  
Metal Oxide Surfaces ◽  
Nucleophilic Addition Reaction ◽  
One Step ◽  
Potential Use ◽  
Polymer Ligand

We designed a new set of polymer ligands that combine multiple metal-coordinating groups and short polyethylene glycol (PEG) moieties in the same structure. The ligand design relies on the controlled grafting of a large number of amine-terminated histamines and PEG short chains onto a poly(isobutylene-alt-maleic anhydride) backbone,viaa one-step nucleophilic addition reaction. This addition reaction is highly efficient, can be carried out in organic media and does not require additional reagents. We show that when imidazole groups are used the resulting polymer ligand can strongly ligate onto metal nanostructures such as nanoparticles (NPs) and nanorods (NRs) made of gold cores. The resulting polymer-coated NPs and NRs exhibit good colloidal stability to pH changes and added electrolytes. This constitutes a departure from the use of thiol-based ligands to coordinate on Au surfaces. The present chemical approach also opens up additional opportunities for designing hydrophilic and reactive platforms where the polymer coating can be adjusted to various metal and metal oxide surfaces by simply modifying or combining the addition reaction with other metal coordinating groups. These could include iron oxide NPs and semiconductor QDs. These polymer-capped NPs and NRs can be used to develop biologically-active platforms with potential use for drug delivery and sensing.

A multi-coordinating polymer ligand optimized for the functionalization of metallic nanocrystals and nanorods

2016 ◽  
Vol 191 ◽  
pp. 481-494 ◽  
Author(s):  
Wentao Wang ◽  
Xin Ji ◽  
Hunter Burns ◽  
Hedi Mattoussi
Keyword(s):  
Gold Nanoparticles ◽  
Colloidal Stability ◽  
Protein Corona ◽  
Growth Media ◽  
Nucleophilic Addition Reaction ◽  
One Step ◽  
Nonspecific Interactions ◽  
Anchoring Groups ◽  
Polymer Ligand

We report the design and use of a multi-coordinating polymer ligand that is ideally suited for functionalizing gold nanoparticles and nanorods, and promoting their steric stabilization in buffer media. The ligand is prepared via a one-step nucleophilic addition reaction between poly(isobutylene-alt-maleic anhydride) and amine-modified anchoring groups and hydrophilic moieties. Surface functionalization of gold nanoparticles and nanorods with this polymer yields nanocrystals that exhibit excellent long-term colloidal stability over a broad range of conditions, including pH changes and in growth media, as verified using dynamic light scattering measurements combined with agarose gel electrophoresis. This polymer coating can also prevent the formation of protein corona. These features bode well for use in biological applications where small size, reduced nonspecific interactions and colloidal stability are highly desired. Furthermore, this design can be easily expanded to functionalize a variety of other inorganic nanocrystals.

Surface-Functionalizing Metal, Metal Oxide and Semiconductor Nanocrystals with a Multi-coordinating Polymer Platform

MRS Advances ◽  
2016 ◽  
Vol 1 (56) ◽  
pp. 3741-3747 ◽  
Author(s):  
Wentao Wang ◽  
Xin Ji ◽  
Anshika Kapur ◽  
Hedi Mattoussi
Keyword(s):  
Self Assembly ◽  
Addition Reaction ◽  
Semiconductor Nanocrystals ◽  
Long Term Stability ◽  
Sensing Platforms ◽  
Metal Metal ◽  
Nucleophilic Addition Reaction ◽  
One Step ◽  
Anchoring Groups

ABSTRACTWe introduce a new set of multifunctional metal-coordinating polymers as ligands for the surface functionalization of three different inorganic nanocrystals: luminescent quantum dots (QDs), magnetic iron oxide nanocrystals and metal gold nanoparticles. The ligand design relies on the introduction of a large but controllable number of anchoring groups, hydrophilic moieties and reactive functionalities all in the same polymer chain, via a one-step nucleophilic addition reaction. Nanocrystals capped with these polymer ligands exhibit long-term stability over a broad range of biological conditions. Furthermore, when zwitterion groups are introduced as hydrophilic blocks, this yields a compact ligand coating that allows conjugation of biomolecules to the nanocrystals via metal-histidine self-assembly. The resulting hydrophilic nanocrystals have been used to develop a few specific sensing platforms targeting soluble iron ions and cysteine.

Controlled in situ reaction for the assembly of Cu(ii) mixed-ligand coordination polymers: synthesis, structure, mechanistic insights, magnetism and catalysis

2015 ◽  
Vol 44 (24) ◽  
pp. 11013-11020 ◽  
Author(s):  
Xing-Po Wang ◽  
Ya-Qin Zhao ◽  
Zvonko Jagličić ◽  
Su-Na Wang ◽  
Shu-Jie Lin ◽  
...  
Keyword(s):  
Coordination Polymers ◽  
Nucleophilic Addition ◽  
Addition Reaction ◽  
Mixed Ligand ◽  
In Situ Reaction ◽  
Nucleophilic Addition Reaction ◽  
Ligand Coordination ◽  
One Step ◽  
The One

Controlled in situ nucleophilic addition reaction results in two Cu(ii) mixed-ligand coordination polymers, and the one-step nucleophilic addition for in situ reaction is proposed.

Instant 99mTc Compounds

1971 ◽  
Vol 10 (03) ◽  
pp. 245-251 ◽  
Author(s):  
P. Richards ◽  
W. C. Eckelman
Keyword(s):  
Physical Properties ◽  
High Purity ◽  
Analytical Techniques ◽  
Full Potential ◽  
Labeled Compounds ◽  
Ph Adjustment ◽  
One Step ◽  
Stannous Ion ◽  
99Mtc Radiopharmaceuticals ◽  
Potential Use

SummaryThe full potential use of technetium has not been achieved despite its ideal physical properties, dosimetry and availability because of the complex preparations required for 99mTc radiopharmaceuticals. One of the goals of our work is to develop techniques for the preparation of high-purity 99mTc compounds which can be easily prepared, ideally by adding pertechnetate to a prepared solution.The use of stannous ion as reducing agent for technetium makes it possible to obtain such one-step, high-purity products. All non-radioactive components can be premixed in a single vial before addition of the radioactive pertechnetate. No final pH adjustment, further chemical manipulation or purification is required.Procedures for two instantly labeled compounds have been developed to date: 99mTc DTPA and 99mTc HSA. The 99mTc DTPA is prepared by adding pertechnetate to a previously prepared solution of stannous ion and CaNa3 DTPA which has been stored at pH 4. The 99mTc HSA is prepared by adding pertechnetate to a solution of stannous ion and HSA. The parametric variations and analytical techniques involved in formulating these procedures are described. It appears that development of kits for other biologically interesting compounds may be possible using similar procedures.

Layer by layer assembled functionalized graphene oxide-based polymer brushes for superlubricity on steel-steel tribocontact

Soft Matter ◽  
2021 ◽  
Author(s):  
Suprakash Samanta ◽  
Rashmi Ranjan Sahoo
Keyword(s):  
Graphene Oxide ◽  
Nucleophilic Addition ◽  
Polymer Brushes ◽  
Addition Reaction ◽  
Layer By Layer ◽  
Functionalized Graphene ◽  
Covalent Functionalization ◽  
Functionalized Graphene Oxide ◽  
Nucleophilic Addition Reaction ◽  
Branched Polyethylenimine

Present study demonstrates a simple and multistep approach for the preparation of covalent functionalization of chemically prepared graphene oxide (GO) by branched polyethylenimine (PEI) through nucleophilic addition reaction to prepare...

High-level production and one-step purification of biologically active human growth hormone in Escherichia coli

Gene ◽  
1995 ◽  
Vol 165 (2) ◽  
pp. 303-306 ◽  
Author(s):  
Reema Mukhija ◽  
Prithy Rupa ◽  
Devika Pillai ◽  
Lalit C. Garg
Keyword(s):  
Escherichia Coli ◽  
Growth Hormone ◽  
Human Growth Hormone ◽  
Human Growth ◽  
Biologically Active ◽  
One Step ◽  
High Level ◽  
Level Production

Novel Ceric Ammonium Nitrate-Stabilized Maghemite Nanoparticles (CAN-γ-Fe2O3) for Ultrasound Assisted Synthesis of β-Amino Derivatives

2021 ◽  
Author(s):  
Anurag Kumar ◽  
Yifat Harel ◽  
Jean-paul Lellouche ◽  
Suman L. Jain
Keyword(s):  
Carbonyl Compounds ◽  
Addition Reaction ◽  
Ceric Ammonium Nitrate ◽  
Reusable Catalyst ◽  
Maghemite Nanoparticles ◽  
Reaction Conditions ◽  
Recyclable Catalysts ◽  
Nucleophilic Addition Reaction ◽  
Amino Derivatives ◽  
Positively Charged

Abstract Owing to their inherent features like smaller size and higher surface area exposed to reactants, nanoparticles have gained enormous interest and are extensively used as magnetically recyclable catalysts for various organic reactions. Herein, we report highly hydrophilic, non-aggregated, and strongly positively charged (ζ potential: +45.7 mV) ultra-small cerium cations/complexes- stabilized maghemite nanoparticles in water as an efficient and reusable nanoscaled magnetically active catalyst for the nucleophilic addition reaction of various amines with α,β-unsaturated carbonyl compounds to give corresponding β-amino derivatives under ultrasonic irradiation. The developed protocol provides several merits such as high product yields, mild reaction conditions, reusable catalyst and easy workup.

Synthesis of biologically active heterocyclic compounds from allenic and acetylenic nitriles and related compounds

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Marthe Carine Djuidje Fotsing ◽  
Dieudonné Njamen ◽  
Zacharias Tanee Fomum ◽  
Derek Tantoh Ndinteh
Keyword(s):  
Michael Addition ◽  
Heterocyclic Compounds ◽  
Biological Activities ◽  
Biologically Active ◽  
Polycyclic Compounds ◽  
One Step ◽  
Pharmaceutical Properties ◽  
Related Compounds ◽  
Acetylenic Acids ◽  
The Michael Addition

Abstract Cyclic and polycyclic compounds containing moieties such as imidazole, pyrazole, isoxazole, thiazoline, oxazine, indole, benzothiazole and benzoxazole benzimidazole are prized molecules because of the various pharmaceutical properties that they display. This led Prof. Landor and co-workers to engage in the synthesis of several of them such as alkylimidazolenes, oxazolines, thiazolines, pyrimidopyrimidines, pyridylpyrazoles, benzoxazines, quinolines, pyrimidobenzimidazoles and pyrimidobenzothiazolones. This review covers the synthesis of biologically active heterocyclic compounds by the Michael addition and the double Michael addition of various amines and diamines on allenic nitriles, acetylenic nitriles, hydroxyacetylenic nitriles, acetylenic acids and acetylenic aldehydes. The heterocycles were obtained in one step reaction and in most cases, did not give side products. A brief discussion on the biological activities of some heterocycles is also provided.

scholarly journals Catalytic Enantioselective Synthesis of 4-Amino-1,2,3,4-tetrahydropyridine Derivatives from Intramolecular Nucleophilic Addition Reaction of Tertiary Enamides

Synlett ◽  
2018 ◽  
Vol 30 (04) ◽  
pp. 483-487 ◽  
Author(s):  
Shuo Tong ◽  
Mei-Xiang Wang
Keyword(s):  
Phosphoric Acid ◽  
Asymmetric Catalysis ◽  
Nucleophilic Addition ◽  
Addition Reaction ◽  
Enantioselective Synthesis ◽  
Chiral Phosphoric Acid ◽  
Substrate Engineering ◽  
Nucleophilic Addition Reaction ◽  
Engineering Strategy ◽  
Acid Catalyzed

A general and efficient method for the synthesis of highly enantiopure 4-amino-1,2,3,4-tetradydropyridine derivatives based on chiral phosphoric acid catalyzed intramolecular nucleophilic addition of tertiary enamides to imines has been developed. We have also demonstrated a substrate engineering strategy to significantly improve the enantioselectivity of asymmetric catalysis

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