Supramolecular gel formation regulated by water content in organic solvents: self-assembly mechanism and biomedical applications

Lieqiang Liao; Xinjian Jia; Haoxiang Lou; Jinlian Zhong; Huijin Liu; Shunming Ding; Chao Chen; Sanguo Hong; Xuzhong Luo

doi:10.1039/d1ra00647a

Norbornene-Functionalised Chitosan Hydrogels and Microgels via an Unprecedented Photo-Initiated Self-Assembly for Potential Biomedical Applications

10.26434/chemrxiv.12340484 ◽

2020 ◽

Author(s):

Sarah michel ◽

Alice Kilner ◽

Jean-Charles Eloi ◽

Sarah E rogers ◽

Wuge H. Briscoe ◽

...

Keyword(s):

Drug Delivery ◽

Self Assembly ◽

Biomedical Applications ◽

Hydrophobic Interactions ◽

Gelation Mechanism ◽

Swelling Behaviour ◽

Assembly Mechanism ◽

Significant Toxicity ◽

Chitosan Hydrogels

Access to biocompatible self-assembled gels and microgels is of great interests for a variety of biological applications from tissue engineering to drug delivery. Here, the facile synthesis of supramolecular hydrogels of norbornene (nb)-functionalised chitosan (CS-nb) via UV-triggered self-assembly in the presence of Irgacure 2959 (IRG) is reported. The in vitro stable hydrogels are injectable and showed pH-responsive swelling behaviour, while their structure and mechanical properties could be tuned by tailoring the stereochemistry of the norbornene derivative (e.g. endo- or -exo). Interestingly, unlike other nb-type hydrogels, the gels possess nanopores within their structure, which might lead to potential drug delivery applications. A gelation mechanism was proposed based on hydrophobic interactions following the combination of IRG on norbornene, as supported by 1H NMR. This self-assembly mechanism was used to access microgels of size 100-150 nm which could be further functionalised and showed no significant toxicity to human dermofibroblast cells.

Download Full-text

Norbornene-Functionalised Chitosan Hydrogels and Microgels via an Unprecedented Photo-Initiated Self-Assembly for Potential Biomedical Applications

10.26434/chemrxiv.12340484.v1 ◽

2020 ◽

Author(s):

Sarah michel ◽

Alice Kilner ◽

Jean-Charles Eloi ◽

Sarah E rogers ◽

Wuge H. Briscoe ◽

...

Keyword(s):

Drug Delivery ◽

Self Assembly ◽

Biomedical Applications ◽

Hydrophobic Interactions ◽

Gelation Mechanism ◽

Swelling Behaviour ◽

Assembly Mechanism ◽

Significant Toxicity ◽

Chitosan Hydrogels

Access to biocompatible self-assembled gels and microgels is of great interests for a variety of biological applications from tissue engineering to drug delivery. Here, the facile synthesis of supramolecular hydrogels of norbornene (nb)-functionalised chitosan (CS-nb) via UV-triggered self-assembly in the presence of Irgacure 2959 (IRG) is reported. The in vitro stable hydrogels are injectable and showed pH-responsive swelling behaviour, while their structure and mechanical properties could be tuned by tailoring the stereochemistry of the norbornene derivative (e.g. endo- or -exo). Interestingly, unlike other nb-type hydrogels, the gels possess nanopores within their structure, which might lead to potential drug delivery applications. A gelation mechanism was proposed based on hydrophobic interactions following the combination of IRG on norbornene, as supported by 1H NMR. This self-assembly mechanism was used to access microgels of size 100-150 nm which could be further functionalised and showed no significant toxicity to human dermofibroblast cells.

Download Full-text

A supramolecular gel based on a glycosylated amino acid derivative with the properties of gel to crystal transition

Soft Matter ◽

10.1039/c5sm02111a ◽

2016 ◽

Vol 12 (1) ◽

pp. 141-148 ◽

Cited By ~ 24

Author(s):

Jie Liu ◽

Fengyang Xu ◽

Ziling Sun ◽

Yue Pan ◽

Jian Tian ◽

...

Keyword(s):

Amino Acid ◽

Acid Derivative ◽

Self Assembly ◽

Amino Acid Derivative ◽

Supramolecular Gel ◽

Crystal Transition

A novel gelator from a glycoamino acid derivative was discovered to perform supramolecular self-assembly and gel–crystal transition upon ageing.

Download Full-text

Stimuli-controlled peptide self-assembly with secondary structure transitions and its application in drug release

Materials Chemistry Frontiers ◽

10.1039/d1qm00430a ◽

2021 ◽

Author(s):

Liu Yang ◽

Shenglong Gan ◽

Qiang Guo ◽

Huatang Zhang ◽

Qingxin Chen ◽

...

Keyword(s):

Secondary Structure ◽

Drug Release ◽

Self Assembly ◽

Biomedical Applications ◽

Short Peptides ◽

Supramolecular Materials

Short peptides can self-assemble into supramolecular materials and be used for promising biomedical applications.

Download Full-text

Fine-Tuning of Molecular Structures to Generate Carbohydrate Based Super Gelators and Their Applications for Drug Delivery and Dye Absorption

Gels ◽

10.3390/gels7030134 ◽

2021 ◽

Vol 7 (3) ◽

pp. 134

Author(s):

Jonathan Bietsch ◽

Mary Olson ◽

Guijun Wang

Keyword(s):

Drug Delivery ◽

Aqueous Solutions ◽

Organic Solvents ◽

Self Assembly ◽

Variable Temperature ◽

Molecular Structures ◽

Fine Tuning ◽

Assembly Mechanism ◽

Amide Derivatives ◽

Structural Connection

Carbohydrate-based low molecular weight gelators (LMWGs) exhibit many desirable properties making them useful in various fields including applications as drug delivery carriers. In order to further understand the structural connection to gelation properties, especially the influence of halide substitutions, we have designed and synthesized a series of para-chlorobenzylidene acetal protected D-glucosamine amide derivatives. Fifteen different amides were synthesized, and their self-assembling properties were assessed in multiple organic solvents, as well as mixtures of organic solvents with water. All derivatives were found to be gelators for at least one solvent and majority formed gels in multiple solvents at concentrations lower than 2 wt%. A few derivatives rendered remarkably stable gels in aqueous solutions at concentrations below 0.1 wt%. The benzamide 13 formed gels in water and in EtOH/H2O (v/v 1:2) at 0.36 mg/mL. The gels were characterized using optical microscopy and atomic force microscopy, and the self-assembly mechanism was probed using variable temperature 1H-NMR spectroscopy. Gel extrusion studies using H2O/DMSO gels successfully printed lines of gels on glass slides, which retained viscoelasticity based on rheology. Gels formed by the benzamide 13 were used for encapsulation and the controlled release of chloramphenicol and naproxen, as well as for dye removal for toluidine blue aqueous solutions.

Download Full-text

Cationic amphiphilic drugs self-assemble to the core–shell interface of PEGylated phospholipid micelles and stabilize micellar structure

Philosophical Transactions of The Royal Society A Mathematical Physical and Engineering Sciences ◽

10.1098/rsta.2012.0309 ◽

2013 ◽

Vol 371 (2000) ◽

pp. 20120309 ◽

Cited By ~ 28

Author(s):

Jing Wang ◽

Xueqing Xing ◽

Xiaocui Fang ◽

Chang Zhou ◽

Feng Huang ◽

...

Keyword(s):

Drug Release ◽

Self Assembly ◽

Polymeric Micelles ◽

Preparation Method ◽

Assembly Method ◽

Phospholipid Micelles ◽

Cationic Amphiphilic Drugs ◽

Assembly Mechanism ◽

Amphiphilic Drugs ◽

Series Of Experiments

Since polymeric micelles are promising and have potential in drug delivery systems, people have become more interested in studying the compatibility of polymeric carriers and drugs, which might help them to simplify the preparation method and increase the micellar stability. In this article, we report that cationic amphiphilic drugs can be easily encapsulated into PEGylated phospholipid (PEG–PE) micelles by self-assembly method and that they show high encapsulation efficiency, controllable drug release and better micellar stability than empty micelles. The representative drugs are doxorubicin and vinorelbine. However, gemcitabine and topotecan are not suitable for PEG–PE micelles due to lack of positive charge or hydrophobicity. Using a series of experiments and molecular modelling, we figured out the assembly mechanism, structure and stability of drug-loaded micelles, and the location of drugs in micelles. Integrating the above information, we explain the effect of the predominant force between drugs and polymers on the assembly mechanism and drug release behaviour. Furthermore, we discuss the importance of p K a and to evaluate the compatibility of drugs with PEG–PE in self-assembly preparation method. In summary, this work provides a scientific understanding for the reasonable designing of PEG–PE micelle-based drug encapsulation and might enlighten the future study on drug–polymer compatibility for other polymeric micelles.

Download Full-text

Cooperative Self-Assembly of Pyridine-2,6-Diimine-Linked Macrocycles into Mechanically Robust Nanotubes

10.26434/chemrxiv.8080043 ◽

2019 ◽

Author(s):

Michael J. Strauss ◽

Darya Asheghali ◽

Austin Evans ◽

Rebecca Li ◽

Anton Chavez ◽

...

Keyword(s):

Aspect Ratio ◽

High Aspect Ratio ◽

Self Assembly ◽

Gel Permeation Chromatography ◽

Synthetic Polymers ◽

Young’S Moduli ◽

Structural Rigidity ◽

Assembly Mechanism ◽

Low Dimensionality ◽

Harsh Conditions

Nanotubes assembled from macrocyclic precursors offer a unique combination of low dimensionality, structural rigidity, and distinct interior and exterior microenvironments. Usually the weak stacking energies of macrocycles limit the length or strength of the resultant nanotubes. Imine-linked macrocycles were recently found to assemble into high-aspect ratio (>103), lyotropic nanotubes in the presence of excess acid. Yet these harsh conditions are incompatible with many functional groups and processing methods, and lower acid loadings instead catalyze macrocycle degradation. Here we report pyridine-2,6-diimine-linked macrocycles that assemble into high-aspect ratio nanotubes in the presence of less than 1 equiv of CF3CO2H per macrocycle. Analysis by gel permeation chromatography and fluorescence spectroscopy revealed a cooperative self-assembly mechanism. Nanofibers obtained by touch-spinning the pyridinium-based nanotubes exhibit Young’s moduli of 1.48 GPa, which exceeds that of many synthetic polymers and biological filaments. These findings will enable the design of structurally diverse nanotubes from synthetically accessible macrocycles.

Download Full-text

The effects of cononsolvents on the synthesis of responsive particles via polymerisation-induced thermal self-assembly

Polymer Chemistry ◽

10.1039/d1py00396h ◽

2021 ◽

Author(s):

Marissa Morales-Moctezuma ◽

Sebastian G Spain

Keyword(s):

Drug Delivery ◽

Tissue Engineering ◽

Self Assembly ◽

Biomedical Applications

Nanogels have emerged as innovative platforms for numerous biomedical applications including gene and drug delivery, biosensors, imaging, and tissue engineering. Polymerisation-induced thermal self-assembly (PITSA) has been shown to be suitable...

Download Full-text