Single-Step Self-Assembly and Physical Crosslinking of PEGylated Chitosan Nanoparticles by Tannic Acid

Chitosan-based nanoparticles are promising materials for potential biomedical applications. We used Flash NanoPrecipitation as a rapid, scalable, single-step method to achieve self-assembly of crosslinked chitosan nanoparticles. Self-assembly was driven by electrostatic interactions, hydrogen bonding, and hydrophobic interactions; tannic acid served to precipitate chitosan to seed nanoparticle formation and crosslink the chitosan to stabilize the resulting particles. The size of the nanoparticles can be tuned by varying formulation parameters including the total solids concentration and block copolymer to core mass ratio. We demonstrated that hydrophobic moieties can be incorporated into the nanoparticle using a lipophilic fluorescent dye as a model system.

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Controlling the Self-Assembly of Biomolecules into Functional Nanomaterials through Internal Interactions and External Stimulations: A Review

Nanomaterials ◽

10.3390/nano9020285 ◽

2019 ◽

Vol 9 (2) ◽

pp. 285 ◽

Cited By ~ 30

Author(s):

Li Wang ◽

Coucong Gong ◽

Xinzhu Yuan ◽

Gang Wei

Keyword(s):

Self Assembly ◽

Electrostatic Interactions ◽

Materials Science ◽

Hydrophobic Interactions ◽

The Self ◽

Functional Nanomaterials ◽

Light Stimulation ◽

Dna Base ◽

Wide Range ◽

Structure And Functions

Biomolecular self-assembly provides a facile way to synthesize functional nanomaterials. Due to the unique structure and functions of biomolecules, the created biological nanomaterials via biomolecular self-assembly have a wide range of applications, from materials science to biomedical engineering, tissue engineering, nanotechnology, and analytical science. In this review, we present recent advances in the synthesis of biological nanomaterials by controlling the biomolecular self-assembly from adjusting internal interactions and external stimulations. The self-assembly mechanisms of biomolecules (DNA, protein, peptide, virus, enzyme, metabolites, lipid, cholesterol, and others) related to various internal interactions, including hydrogen bonds, electrostatic interactions, hydrophobic interactions, π–π stacking, DNA base pairing, and ligand–receptor binding, are discussed by analyzing some recent studies. In addition, some strategies for promoting biomolecular self-assembly via external stimulations, such as adjusting the solution conditions (pH, temperature, ionic strength), adding organics, nanoparticles, or enzymes, and applying external light stimulation to the self-assembly systems, are demonstrated. We hope that this overview will be helpful for readers to understand the self-assembly mechanisms and strategies of biomolecules and to design and develop new biological nanostructures or nanomaterials for desired applications.

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Self-Assembly of Diphenylalanine-Based Nanostructures in Water and Electrolyte Solutions

Journal of Nanomaterials ◽

10.1155/2018/8140954 ◽

2018 ◽

Vol 2018 ◽

pp. 1-7 ◽

Cited By ~ 10

Author(s):

Sergio M. Acuña ◽

María C. Veloso ◽

Pedro G. Toledo

Keyword(s):

Electron Microscopy ◽

Self Assembly ◽

Electrostatic Interactions ◽

Hydrophobic Interactions ◽

Electrolyte Solutions ◽

Salt Solutions ◽

Shape Information ◽

Transmission Electron ◽

Structure Breaking ◽

Scanning Electron

Diphenylalanine (FF) is a peptide that can form different nanostructures; this makes it particularly attractive for both biological and technological applications. However, any application using this type of nanostructures requires controlling their size and shape. Information is provided about the various structures formed through the peptide FF self-assembly in different salt solutions (NaCl, CaCl2, and AlCl3), concentrations (50 mM, 100 mM, and 200 mM), and pH (3 to 10). Transmission electron microscopy (TEM), scanning electron microscopy (SEM), and Fourier-transform infrared (FTIR) spectroscopy were used to characterize the nanotubes. Results show that FF nanotube formation through self-assembly is a delicate balance between electrostatic, hydrogen bonding, and hydrophobic interactions; any imbalance in these can impede nanotube formation. Our results demonstrate that salts, such as NaCl and CaCl2, along with the studied concentrations promote the formation of very long nanotube agglomerates. This would be due to a combined screening effect and the fact that cations are structure-forming and promote hydrophobic interactions; therefore, nanotube agglomeration occurs and also benefits electrostatic interactions, hydrogen bonds, and longer nanotubes. The presence of AlCl3 produces an imbalance in the abovementioned interactions because of excess Cl-, a structure-breaking anion that impedes the nanostructure formation.

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MATERIALS SELECTION FOR PRODUCTION OF MICROSPHERES PROTECTING LACTOFERRIN UNDER ACID CONDITIONS

Science Evolution ◽

10.21603/2500-1418-2016-1-1-92-102 ◽

2016 ◽

pp. 92-102 ◽

Cited By ~ 2

Author(s):

Marina Novoselova ◽

Alexander Prosekov ◽

Alexander Prosekov

Keyword(s):

Tannic Acid ◽

Electrostatic Interactions ◽

Hydrophobic Interactions ◽

Inflammatory Diseases ◽

Adsorbed Layer ◽

Multifunctional Protein ◽

Acidic Conditions ◽

Selection For ◽

The Stability ◽

Subsequent Layer

Lactoferrin is a multifunctional protein of the transferrin family, which can be found in the human and other mammals milk. On the basis of many biological functions of lactoferrin, researchers have considered various possibilities of its application in health care, in the prevention and treatment of infectious and inflammatory diseases. However, lactoferrin is exposed to pepsin degradation in the gastrointestinal tract, decreasing its bioactivity after oral administration. In this regard, appropriate delivery system of lactoferrin, which ensures its delivery intact to the receptors in the small intestine requires. In this study, the different compositions of the capsules in combination with tannic acid, formed mainly by hydrogen and hydrophobic interactions were showed. Its stability toward acidic conditions (0.1 M HCl) was investigated. Complexes with polyelectrolytes (and its pairs): PSS/PAH, Parg as the first adsorbed layer on CaCO3 particles formed by electrostatic interactions were presented. As the results, the adsorption of these polyelectrolytes led to greater stability of the obtained capsules. Bovine serum albumin and tannic acid, in particular with the use of poly-L-arginine as the first layer, increasing the stability of the obtained microspheres were selected as the most promising materials for the microcapsules synthesis. The changes in the morphology of [BSA/TA] and Parg [BSA/TA] capsules depending on the various number of bilayers (from 3 to 6) were analyzes. The thickness of capsule was increased on 1-2 nm by applying each subsequent layer. It was noted BSA/TA capsules looked thinner than Parg [BSA/TA] capsules with the same number of bilayers.

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Rapid, Single-Step Protein Encapsulation via Flash NanoPrecipitation

Polymers ◽

10.3390/polym11091406 ◽

2019 ◽

Vol 11 (9) ◽

pp. 1406 ◽

Cited By ~ 3

Author(s):

Shani L. Levit ◽

Rebecca C. Walker ◽

Christina Tang

Keyword(s):

Self Assembly ◽

Electrostatic Interactions ◽

Cationic Polyelectrolyte ◽

Single Step ◽

Protein Encapsulation ◽

Flash Nanoprecipitation ◽

Hydrophobic Materials ◽

Model Protein ◽

Processing Steps ◽

Multiple Processing

Flash NanoPrecipitation (FNP) is a rapid method for encapsulating hydrophobic materials in polymer nanoparticles with high loading capacity. Encapsulating biologics such as proteins remains a challenge due to their low hydrophobicity (logP < 6) and current methods require multiple processing steps. In this work, we report rapid, single-step protein encapsulation via FNP using bovine serum albumin (BSA) as a model protein. Nanoparticle formation involves complexation and precipitation of protein with tannic acid and stabilization with a cationic polyelectrolyte. Nanoparticle self-assembly is driven by hydrogen bonding and electrostatic interactions. Using this approach, high encapsulation efficiency (up to ~80%) of protein can be achieved. The resulting nanoparticles are stable at physiological pH and ionic strength. Overall, FNP is a rapid, efficient platform for encapsulating proteins for various applications.

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Purification of Urokinase from Complex Mixtures Using Immobilized Monoclonal Antibody Against Urokinase Light Chain

Thrombosis and Haemostasis ◽

10.1055/s-0038-1657308 ◽

1983 ◽

Vol 49 (01) ◽

pp. 024-027 ◽

Cited By ~ 20

Author(s):

David Vetterlein ◽

Gary J Calton

Keyword(s):

Monoclonal Antibody ◽

Light Chain ◽

Culture Media ◽

Biological Fluids ◽

Single Step ◽

High Yield ◽

Step Method ◽

Commercial Preparation ◽

E Coli ◽

Tissue Culture Media

SummaryThe preparation of a monoclonal antibody (MAB) against high molecular weight (HMW) urokinase light chain (20,000 Mr) is described. This MAB was immobilized and the resulting immunosorbent was used to isolate urokinase starting with an impure commercial preparation, fresh urine, spent tissue culture media, or E. coli broth without preliminary dialysis or concentration steps. Monospecific antibodies appear to provide a rapid single step method of purifying urokinase, in high yield, from a variety of biological fluids.

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

10.26434/chemrxiv.9876395.v1 ◽

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.

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Self-Crosslinked Ellipsoidal Poly(Tannic Acid) Particles for Bio-Medical Applications

Molecules ◽

10.3390/molecules26092429 ◽

2021 ◽

Vol 26 (9) ◽

pp. 2429

Author(s):

Nurettin Sahiner

Keyword(s):

Tannic Acid ◽

Hydrolytic Degradation ◽

Single Step ◽

Trolox Equivalent Antioxidant Capacity ◽

Total Phenol Content ◽

Frap Assay ◽

E Coli ◽

Gram Positive Bacteria ◽

Trolox Equivalent ◽

Free Media

Self-crosslinking of Tannic acid (TA) was accomplished to obtain poly(tannic acid) (p(TA)) particles in single step, surfactant free media using sodium periodate (NaIO4) as an oxidizing agent. Almost monodisperse p(TA) particles with 981 ± 76 nm sizes and −22 ± 4 mV zeta potential value with ellipsoidal shape was obtained. Only slight degradation of p(TA) particles with 6.8 ± 0.2% was observed at pH 7.4 in PBS up to 15 days because of the irreversible covalent formation between TA units, suggesting that hydrolytic degradation is independent from the used amounts of oxidation agents. p(TA) particles were found to be non-hemolytic up to 0.5 mg/mL concentration and found not to affect blood clotting mechanism up to 2 mg/mL concentration. Antioxidant activity of p(TA) particles was investigated by total phenol content (TPC), ferric reducing antioxidant potential (FRAP), trolox equivalent antioxidant capacity (TEAC), total flavanoid content (TFC), and Fe (II) chelating activity. p(TA) particles showed strong antioxidant capability in comparison to TA molecules, except FRAP assay. The antibacterial activity of p(TA) particles was investigated by micro-dilution technique on E. coli as Gram‑negative and S. aureus as Gram-positive bacteria and found that p(TA) particles are more effective on S. aureus with over 50% inhibition at 20 mg/mL concentration attained.

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High-resolution limited-angle phase tomography of dense layered objects using deep neural networks

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1821378116 ◽

2019 ◽

Vol 116 (40) ◽

pp. 19848-19856 ◽

Cited By ~ 12

Author(s):

Alexandre Goy ◽

Girish Rughoobur ◽

Shuai Li ◽

Kwabena Arthur ◽

Akintunde I. Akinwande ◽

...

Keyword(s):

Integrated Circuit ◽

Deep Neural Networks ◽

Tomographic Reconstruction ◽

Synthetic Data ◽

Single Step ◽

Training Set ◽

Step Method ◽

3 Dimensional ◽

Dimensional Reconstruction ◽

Optical Domain

We present a machine learning-based method for tomographic reconstruction of dense layered objects, with range of projection angles limited to ±10○. Whereas previous approaches to phase tomography generally require 2 steps, first to retrieve phase projections from intensity projections and then to perform tomographic reconstruction on the retrieved phase projections, in our work a physics-informed preprocessor followed by a deep neural network (DNN) conduct the 3-dimensional reconstruction directly from the intensity projections. We demonstrate this single-step method experimentally in the visible optical domain on a scaled-up integrated circuit phantom. We show that even under conditions of highly attenuated photon fluxes a DNN trained only on synthetic data can be used to successfully reconstruct physical samples disjoint from the synthetic training set. Thus, the need for producing a large number of physical examples for training is ameliorated. The method is generally applicable to tomography with electromagnetic or other types of radiation at all bands.

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