Self-assembled Hydrogels Research Articles

How Chromophore Labels Shape the Structure and Dynamics of a Peptide Hydrogel.

Biocompatible and functionalizable hydrogels have a wide range of (potential) medicinal applications. The hydrogelation process, particularly for systems with very low polymer weight percentages (<1 wt %), remains poorly understood, making it challenging to predict the self-assembly of a given molecular building block into a hydrogel. This severely hinders the rational design of self-assembled hydrogels. In this study, we demonstrate the impact of an N-terminal group on the self-assembly and rheology of the peptide hydrogel hFF03 (hydrogelating, fibril forming peptide 03) using molecular dynamics simulations, oscillatory shear rheology, and circular dichroism spectroscopy. We find that the chromophore and even its specific regioisomers have a significant influence on the microscopic structure and dynamics of the self-assembled fibril, and on the macroscopic mechanical properties. This is because the chromophore influences the possible salt bridges, which form and stabilize the fibril formation. Furthermore, we find that the solvation shell fibrils by itself cannot explain the viscoelasticity of hFF03 hydrogels. Our atomistic model of the hFF03 fibril formation enables a more rational design of these hydrogels. In particular, altering the N-terminal chromophore emerges as a design strategy to tune the mechanic properties of these self-assembled peptide hydrogels.

Ovalbumin amyloid-like fibrils/resveratrol self-assembling hydrogel: Preparation, characterization and formation mechanism

Food protein amyloid-like fibrils can significantly increase solution viscosity and promote the formation of entangled gel network due to its high stiffness and extreme aspect ratios. In this study, the ability of hydrophobic resveratrol (RES) deposited on the surface of the ovalbumin (OVA) amyloid-like fibrils (OVAF) to form a new self-assembling hydrogel was explored. The results showed that the simple mixing of RES and OVAF at pH 6.5 can successfully drive the formation of hybrid hydrogels through molecular self-assembly. The interactions between OVAF and RES were confirmed by the results of transmission electron microscope and fluorescence spectra. Non-covalent interactions including hydrophobic interactions and hydrogen bonds played an important role in the formation of the OVAF/RES self-assembling hydrogels. Furthermore, the OVAF/RES hydrogel showed a dense structure, high water holding capacity and remarkable rheological properties. The viscosity and storage modulus of the hybrid hydrogels increased with the increase of the RES and OVAF concentrations. After gastrointestinal digestion, some fibrous structures in the OVAF/RES hydrogels remained, which allowed for continuous release of RES. In summary, the OVAF/RES hybrid hydrogels with tunable structures, encapsulation ability and self-assembly characteristics are expected to be candidates for the delivery of hydrophobic active polyphenols in the food industry.

A Nucleic Acid-Based LYTAC Plus Platform to Simultaneously Mediate Disease-Driven Protein Downregulation.

Protein degradation techniques, such as proteolysis-targeting chimeras (PROTACs) and lysosome-targeting chimeras (LYTACs), have emerged as promising therapeutic strategies for the treatment of diseases. However, the efficacy of current protein degradation methods still needs to be improved to address the complex mechanisms underlying diseases. Herein, a LYTAC Plus hydrogel engineered is proposed by nucleic acid self-assembly, which integrates a gene silencing motif into a LYTAC construct to enhance its therapeutic potential. As a proof-of-concept study, vascular endothelial growth factor receptor (VEGFR)-binding peptides and mannose-6 phosphate (M6P) moieties into a self-assembled nucleic acid hydrogel are introduced, enabling its LYTAC capability. Small interference RNAs (siRNAs) is then employed that target the angiopoietin-2 (ANG-2) gene as cross-linkers for hydrogel formation, giving the final LYTAC Plus hydrogel gene silencing ability. With dual functionalities, the LYTAC Plus hydrogel demonstrated effectiveness in simultaneously reducing the levels of VEGFR-2 and ANG-2 both in vitro and in vivo, as well as in improving therapeutic outcomes in treating neovascular age-related macular degenerationin a mouse model. As a general material platform, the LYTAC Plus hydrogel may possess great potential for the treatment of various diseases and warrant further investigation.

A Drop-By-Drop Self-Assembled All-Natural Hydrogel as a Desensitizer for Rapid and Enduring Management of Dentin Hypersensitivity.

Dentin hypersensitivity (DH) is a prevalent dental condition arising from the exposure of dentin tubules (DTs), leading to discomfort upon external stimuli. However, achieving swift and profound occlusion of these exposed DTs for immediate and enduring relief remains challenging due to the intricate dentin structure and oral environment. Herein, a pioneering and facile drop-by-drop strategy involving an in situ generated natural supramolecular hydrogel formed by self-assembling silk fibroin (SF) and tannic acid (TA) within the narrow DT space is proposed. When SF and TA aqueous solutions are applied successively to exposed dentin, they penetrate deeply within DTs and coassemble into compact gels, robustly adhering to DT walls. This yields a rapid and compact occlusion effect with an unprecedented depth exceeding 250µm, maintaining stable occlusion efficacy even under rigorous in vitro and in vivo erosion and friction conditions for no less than 21 days. Furthermore, the biocompatibility and effective occlusion properties are verified through cell studies in simulated oral settings and an in vivo rabbit model. This study, for the first time, demonstrates the translational potential of hydrogel-based desensitizers in treating DH with prompt action, superior occlusion depth and enduring treatment benefits, holding promise as clinical-friendly restorative solutions for delicate-structured biosystems.

Lysine-based non-cytotoxic ultrashort self-assembling peptides with antimicrobial activity.

Peptide-based molecules and their hydrogels are useful materials for biomedical applications due to the reversible nature of their self-assembly as well as the diversity of nanostructures that can be created starting from low-molecular weight compounds. In this study, we have focused on comprehending the characteristics of fibrillar networks of l-lysine-based self-assembled dipeptide hydrogels with a focus on their antibacterial properties. For that purpose, l-lysine has been complemented with hydrophobic aromatic moieties coming from l-phenylalanine and benzyloxyxarbonyl N-capping. In addition, the peptide C-terminus is blocked with alkylamides of different chain lengths which introduces additional dispersive interactions and hydrophobicity. These materials were well characterized by transmission electron microscopy, scanning electron microscopy, wide-angle powder X-ray diffraction and oscillatory rheology. Finally, biocompatibility and antimicrobial tests were performed showing that these hydrogels are compatible with HEK 293 cells and present a remarkable antibacterial activity against both Gram positive (S. aureus) and Gram negative (E. coli) bacteria.

A self-assembling bioactive oligopeptide hydrogel for the treatment of edema following prepuce surgery.

Edema of the prepuce is a common clinical complication following circumcision in urology. Nevertheless, the principal method of gauze wrapping in clinical practice has not yet been demonstrated to be an effective solution to the problem of postoperative edema. It is therefore evident that the development of functional dressings for the treatment of post-circumcision edema has considerable potential for both clinical application and translational significance. The objective of this study was to develop a single-component bioactive oligopeptide hydrogel dressing with favorable anti-inflammatory, pro-angiogenesis properties and biosafety for the treatment of edema following prepuce surgery. A hexapeptide (Ac-FFFGHK-OH) hydrogelator was designed and synthesized through the N-terminal modification of a human-derived glycine-histidine-lysine tripeptide (GHK) with an N-acetylated phenylalanine tripeptide (Ac-FFF). The bioactive Ac-FFFGHK-OH hydrogel can be prepared through a facile self-assembly method. Furthermore, a novel experimental animal model of post-circumcision edema in Sprague-Dawley rats was constructed and the in vivo anti-edema effect of the Ac-FFFGHK-OH hydrogel was confirmed. The mechanism of action in relieving edema was also investigated by in vitro cell experiments. This work may inspire alternative thinking for the development of mono-component bioactive oligopeptide hydrogels for the treatment of edema in various diseases.

Accelerated self-assembly of filipin proteins and formation of hydrogels

This study delineates the novel revelation that traditional Chinese medicine polysaccharides facilitate and expedite the intramolecular conformational alterations within filipin proteins, culminating in amplified β-fold content and self-assembly proclivity to generate hydrogels. Augmentation of assembly kinetics was achieved by pH or ethanol supplementation. The resultant self-assembled hydrogels exhibited homogenous pore size distribution, registering porosities consistently surpassing 95 ± 2.3%, effectively accommodating pharmaceutical payloads. Noteworthy characteristics included low water loss rates spanning between 15% and 25%, exceptional swelling behavior, a storage modulus (G') ranging from 68 to 283 Pa, and discernible mechanical robustness. Insights into the self-assembly mechanism were preliminarily explained via Fourier infrared, Raman spectroscopy and X-ray diffraction spectroscopy analyses. In-depth examinations, encompassing in-vitro release, degradation and biocompatibility, corroborated the hydrogel’s capacity for smooth drug release, sustained stability, absence of cytotoxicity and favorable biocompatibility. In conclusion, the self-assembled filipin protein hydrogels preserved polysaccharide activity to a heightened extent and enhanced drug adaptability by reducing the overall formulation volume. This innovation, we suggest, holds significant promise for applications in sustained drug release and in the realm of tissue engineering materials.

A self-assembling peptide nanofiber hydrogel for biomaterials with rapid stimulation response to naturally positively charged group substances

Peptides as unique supramolecular nanofibrous materials are favored choices to fabricate hydrogel for artificial extracellular matrices. Herein, we devised an amphiphilic polypeptide that could be motivated by multiple substances with positively charged group at physiological temperature and pH to assemble supramolecular nanofiber hydrogels since the electrostatic repulsion between monomers was attenuated. The hydrogelation phenomenon and spectroscopy were compatible with molecular dynamics simulations (MDs) results for revealing the assembly mechanism of this peptide, confirming that the behavior of assembling and the typical secondary structure of the assemblies was β-sheet. The impact of peptide concentration on the mechanical properties of hydrogels were described using rheology. We found that the peptide formed elastic gels from 0.3 wt% onwards in practical use and that these recovered by themselves after shear thinning that indicated they were injectable hydrogels. The successful establishment of cell spheres with high cell viability during 15 days culture in 3D space demonstrated the nanofiber hydrogels had potential in cell model construction and microtissue culture. Overall, the superior biologically friendly gel-forming conditions and excellent biological properties of this supramolecular assembly peptide material have invigorated the progress of biomedical fields such as tissue regeneration based on in vitro 3D culture.

A novel bola-molecular self-assembling hydrogel for enhancing diabetic wound healing

HypothesisChronic wounds, particularly those caused by diabetes, pose a significant challenge for clinical treatment due to their prolonged healing process and associated complications, which can lead to increased morbidity. A biocompatible hydrogel with strong antibacterial properties and the ability to promote angiogenesis can be directly absorbed in the wound site for healing. ExperimentsA series of self-healing, antibacterial bolaamphiphilic supramolecular self-assembling hydrogels (HLQMes/Cu) were developed based on metal–ligand coordination between various concentrations of Cu2+ solution and the head group of l-histidine methyl ester in HLQMes. This is the first report on the application of bola-molecular supramolecular hydrogels for the treatment of chronic wounds. FindingsThe bola-molecular hydrogels reduced the toxicity of copper ions by coordination, and the HLQMes/Cu hydrogel, with 1.3 mg/mL Cu2+ (HLQMes/Cu1.3), demonstrated good biocompatibility and antibacterial properties and effectively enhanced wound healing in a diabetic wound model with full-thickness injuries. Immunohistochemical analysis revealed that the HLQMes/Cu1.3 hydrogel enhanced epithelial formation and collagen deposition in wounds. Immunofluorescence studies confirmed that the HLQMes/Cu1.3 hydrogel attenuated the expression of proinflammatory factor (IL-6) and promoted angiogenesis by upregulating α-SMA and CD31. These findings demonstrate the potential of this bolaamphiphilic supramolecular self-assembling hydrogel as a promising candidate for diabetic wound treatment.

Sustained delivery of chemically modified mRNA encoding amelogenin from self-assembling hydrogels for periodontal regeneration

Periodontitis is a growing clinical problem worldwide. Despite various approaches that have been devoted to repairing periodontal defects, the clinical outcomes are still limited due to the decline in tissue regenerative potential after periodontitis. Fortunately, chemically modified mRNA (modRNA)-based therapeutics have emerged as a promising strategy to combat incurable diseases. However, the use of modRNA for treating periodontitis is rare and challenging. Herein, a novel therapeutic mRNA platform that allows for sustained delivery and targeted osteogenesis and cementogenesis was developed for periodontal regeneration by combining a self-assembling PLA-PEG-PLA hydrogel and newly synthesized modRNA encoding amelogenin (AMELX) via in vitro transcription. The thermosensitive PLA-PEG-PLA hydrogel significantly prevented modRNA degradation and prolonged the release of encapsulated modRNA by forming an in situ hydrogel depot at 37 °C, resulting in sustained and strong expression of AMELX in human periodontal ligament stem cells (PDLSCs). Moreover, the AMELX modRNA exhibited a great capacity for promoting osteogenesis and cementogenesis of PDLSCs, as evidenced by elevated alkaline phosphatase (ALP) activity, calcium nodule formation, and osteogenesis- and cementogenesis-related gene expression (e.g., ALP, BMP2, CAP, BSP, COL1A1). As a result, after a single local injection, the PLA-PEG-PLA hydrogel enabled AMELX modRNA to persist and release at the defect site, thus successfully regenerating bone and periodontal ligament tissues in periodontal defects of rats. These findings provide a new approach for treating periodontal defects using self-assembling hydrogels to enable safe and effective delivery of AMELX modRNA, thereby offering various possibilities for functional tissue reconstruction with mRNA therapeutics.

A novel octa-arginine-modified injectable self-assembling peptide hydrogel for multidrug-resistant cancer therapy

Surgery combined with systemic chemotherapy is currently the main modality of cancer treatment. However, the development of cancer multidrug resistance and inevitable surgical residual lesions lead to high rates of cancer recurrence and mortality. Meanwhile, systemic drug toxic side effects and surgical bleeding complications seriously reduce the quality of life of patients. To avoid cancer multidrug resistance and comprehensively optimize cancer treatment, this work provides a novel injectable cell penetrating peptide octa-arginine (R8)-modified RADA16 (RR) self-assembling peptide nanofiber hydrogel as an anticancer drug carrier for multidrug-resistant cancer therapy. In RR hydrogel, highly compatible RADA16 functions as the β-sheet-based self-assembling backbone which tightly adheres to cancer tissue, prevents postoperative bleeding, and sustainedly releases anticancer drugs for long-term effects. The introduced R8 motifs endow RR hydrogel with the capacity to selectively kill cancer cells and reverse cancer multidrug resistance, which minimally impact normal tissue cells. Specifically, R8 motifs on the hydrogel scaffold selectively interfere with cancer cell membranes, increase drug uptake and penetration into cancer cells and tissues by enhancing multiple internalization pathways, and reduce drug efflux by inhibiting P-gp and BCRP multidrug-resistant transporters. Therefore, this study provides a multifunctional hydrogel material with strong potential for multidrug-resistant cancer clinical translation.

Injectable CNPs/DMP1-loaded self-assembly hydrogel regulating inflammation of dental pulp stem cells for dentin regeneration

Vital pulp preservation, which is a clinical challenge of aseptic or iatrogenic accidental exposure of the pulp, in cases direct pulp capping is the main technology. Human dental pulp stem cells (hDPSCs) play a critical role in pulp tissue repair, but their differentiative ability could be inhibited by the potential infection and inflammatory response of the exposed pulp. Therefore, inflammatory regulation and differentiated promotion of hDPSCs are both essential for preserving living pulp teeth. In this study, we constructed a functional dental pulp-capping hydrogel by loading cerium oxide nanoparticles (CNPs) and dentin matrix protein-1 (DMP1) into an injectable Fmoc–triphenylalanine hydrogel (Fmoc-phe3 hydrogel) as CNPs/DMP1/Hydrogel for in situ drugs delivery. With a view to long-term storage and release of CNPs (anti-inflammatory and antioxidant) to regulate the local inflammatory environment and DMP1 to promote the regeneration of dentin. Results of CCK-8, LDH release, hemolysis, and Live/Dead assessment of cells demonstrated the good biocompatibility of CNPs/DMP1/Hydrogel. The levels of alkaline phosphatase activity, quantification of the mineralized nodules, expressions of osteogenic genes and proteins demonstrated CNPs/DMP1/Hydrogel could protect the activity of hDPSCs’ osteogenic/dentinogenic differentiation by reducing the inflammation response via releasing CNPs. The therapy effects were further confirmed in rat models, CNPs/DMP1/Hydrogel reduced the necrosis rate of damaged pulp and promoted injured pulp repair and reparative dentin formation with preserved vital pulps. In summary, the CNPs/DMP1/Hydrogel composite is an up-and-coming pulp-capping material candidate to induce reparative dentin formation, as well as provide a theoretical and experimental basis for developing pulp-capping materials.

Self-assembled silk fibroin injectable hydrogels based on layered double hydroxides for spinal cord injury repair

Self-assembled silk fibroin injectable hydrogels based on layered double hydroxides for spinal cord injury repair

Biosynthesis of Peptide Hydrogel-Titania Nanoparticle Composites with Antibacterial Properties.

The photoantibacterial properties of titania nanoparticles (TiO2NPs) are attracting much interest, but the separation of their suspension limits their application. In this study, the encapsulation of commercial TiO2NPs within self-assembling tripeptide hydrogels to form hgel-TiO2NP composites with significant photoantibacterial properties is reported. The Fmoc-Phe3 hydrogelator was synthesized via an enzymatic method. The resulting composite was characterized with DLS, ζ-potential, SAXS, FESEM-EDS and rheological measurements. Two different concentrations of TiO2NPs were used. The results showed that, by increasing the TiO2NP quantity from 5 to 10 mg, the value of the elastic modulus doubled, while the swelling ratio decreased from 63.6 to 45.5%. The antimicrobial efficacy of hgel-TiO2NPs was tested against a laboratory Staphylococcus aureus (S. aureus) strain and two methicillin-resistant S. aureus (MRSA) clinical isolates. Results highlighted a concentration-dependent superior antibacterial activity of hgel-TiO2NPs over TiO2NPs in the dark and after UV photoactivation. Notably, UV light exposure substantially increased the biocidal action of hgel-TiO2NPs compared to TiO2NPs. Surprisingly, in the absence of UV light, both composites significantly increased S. aureus growth relative to control groups. These findings support the role of hgel-TiO2NPs as promising biocidal agents in clinical and sanitation contexts. However, they also signal concerns about TiO2NP exposure influencing S. aureus virulence.

Development and evaluation of RADA-PDGF2 self-assembling peptide hydrogel for enhanced skin wound healing

Background: Wound healing complications affect numerous patients each year, creating significant economic and medical challenges. Currently, available methods are not fully effective in the treatment of chronic or complicated wounds; thus, new methods are constantly sought. Our previous studies showed that a peptide designated as PDGF2 derived from PDGF-BB could be a promising drug candidate for wound treatment and that RADA16-I can serve as a release system for bioactive peptides in wound healing. Based on that, in this work, we designed a new self-assembling hydrogel RADA-PDGF2, connecting both peptides by a sequence specific for neutrophil elastase, and evaluated its activity in wound healing.Methods: The physicochemical properties of the designed scaffold were analyzed using transmission electron microscopy, atomic force microscopy, cryoSEM microscopies, and circular dichroism spectroscopy. The enzymatic cleavage was performed using human neutrophil elastase and monitored using high-performance liquid chromatography and MS spectroscopic techniques. The aforementioned techniques (HPLC and MS) were also used to assess the stability of the peptide in water and human plasma. The biological activity was analyzed on human skin cells using a colorimetric XTT test, collagen synthesis evaluation, and a migration assay. The biocompatibility was analyzed with LDH cytotoxicity assay and flow cytometric analysis of activation of immune cells. Finally, RADA-PDGF2 activity in wound healing was checked in a mouse dorsal skin injury model.Results: The analysis showed that RADA-PDGF2 can self-assemble, form a hydrogel, and release a bioactive sequence when incubated with human elastase. It shows pro-proliferative and pro-migratory properties and accelerates wound closure in the mouse model compared to RADA16-I. In addition, it is not cytotoxic to human cells and does not show immunogenicity. RADA-PDGF2 seems to be a promising drug candidate for wound management.

A self-assembled hydrogel dressing as multi-target therapeutics to promote wound healing

Wound healing is one of the major challenges in biomedicine owing to the absence of ideal wound dressings which can integrate easy absorption, satisfied injectability, rapid self-healing property, and multiple therapeutic effects into one system. Here, we explore a self-assembled supramolecular hydrogel composed of herbal cinnamaldehyde (CA) and folic acid (FA). This enables the Schiff base and the Ionic crosslinking as a dynamic double cross-linked network. This nano-scale hydrogel (C-FA-gel) maintains good adhesion and is apt to get peeled off from tissues without any residuals. Further experiments show a percutaneous absorption within 12 h after the hydrogel dressing perfectly fills the irregular wound by injection on pig skin. For muti-target therapeutics, the drug sustained-release of C-FA-gel exhibits broad-spectrum antibacterial activities without evident cytotoxicity. Besides, the topical dressing on rat skin promotes wound healing via multifunctional effects including inflammatory reduction, facilitation of the angiogenesis improvement, and regeneration promotion of skin appendages. Moreover, the C-FA-gel induces anti-inflammatory macrophages from pro-inflammatory macrophages. Therefore, we successfully present a self-assembled hydrogel using the ‘one system’ strategy. This study offers a green and efficient design for the potential to be applied to complicated wound treatment.

Cartilage-inspired self-assembly glycopeptide hydrogels for cartilage regeneration via ROS scavenging

Cartilage injury represents a frequent dilemma in clinical practice owing to its inherently limited self-renewal capacity. Biomimetic strategy-based engineered biomaterial, capable of coordinated regulation for cellular and microenvironmental crosstalk, provides an adequate avenue to boost cartilage regeneration. The level of oxidative stress in microenvironments is verified to be vital for tissue regeneration, yet it is often overlooked in engineered biomaterials for cartilage regeneration. Herein, inspired by natural cartilage architecture, a fibril-network glycopeptide hydrogel (Nap-FFGRGD@FU), composed of marine-derived polysaccharide fucoidan (FU) and naphthalenephenylalanine-phenylalanine-glycine-arginine-glycine-aspartic peptide (Nap-FFGRGD), was presented through a simple supramolecular self-assembly approach. The Nap-FFGRGD@FU hydrogels exhibit a native cartilage-like architecture, characterized by interwoven collagen fibers and attached proteoglycans. Beyond structural simulation, fucoidan-exerted robust biological effects and Arg-Gly-Asp (RGD) sequence-provided cell attachment sites realized functional reinforcement, synergistically promoted extracellular matrix (ECM) production and reactive oxygen species (ROS) elimination, thus contributing to chondrocytes-ECM harmony. In vitro co-culture with glycopeptide hydrogels not only facilitated cartilage ECM anabolic metabolism but also scavenged ROS accumulation in chondrocytes. Mechanistically, the chondro-protective effects induced by glycopeptide hydrogels rely on the activation of endogenous antioxidant pathways associated with nuclear factor erythroid 2-related factor 2 (NRF2). In vivo implantation of glycopeptide hydrogels successfully improved the de novo cartilage generation by 1.65-fold, concomitant with coordinately restructured subchondral bone structure. Collectively, our ingeniously crafted bionic glycopeptide hydrogels simultaneously rewired chondrocytes’ function by augmenting anabolic metabolism and rebuilt ECM microenvironment via preserving redox equilibrium, holding great potential for cartilage tissue engineering.

Self-gelation techniques for amoxicillin: formulation and characterization

Self-assembled hydrogels without structural alterations have been a topic of considerable interest. Here, a novel self-assembled amoxicillin hydrogel devoid of any gelling substances or structural modifications was formulated with high stability. The minimum gelator concentration (MGC) was 7.14 wt.% and the gel dissociation temperature (Tgel) was found to be 43.1 °C. The formulated gel was further characterized using FE-SEM, 1H NMR, FT-IR, XRD, rheology, and contact angle measurements, which provided strong evidence in favor of the formation of hydrogel. Furthermore, computational study of gel network formation and kinetic study of amoxicillin release found that the gel exhibited an excellent release rate.

Thermo-reversible self-assembled novel gellan gum hydrogels containing amino acid biogelators with antibacterial activity

In recent years, hydrogels derived from natural polymers have gained considerable attention. However, lack of mechanical strength and poor stability has become major lacuna of such systems. Scientists have attempted to resolve this problem by introducing chemical cross-linkers or synthetic modifications of natural polymers. In contrast, biological cross-linkers may be more beneficial due to their cytocompatibility and non-immunogenicity. As a biogelator, amino acids (AA) may be lucrative, yet they remain untapped till date. Present study, for the first time, reports exploitation of ʟ-Lysine, ʟ-Arginine, ʟ-Aspartic acid, and ʟ-Glutamic acid as biogelator to fabricate novel gellan gum (GG) hydrogels through green chemistry. Furthermore, as a first instance, molecular docking was applied to gain insight into the interaction between GG and AA. As predicted through docking, physical cross-linking of these hydrogels accounted for their thermo-reversibility. Moreover, to assess the suitability of prepared hydrogel for its intended use, systematic characterization studies were performed via FTIR, Raman spectroscopy, XRD, FE-SEM, and TGA. Additionally, rheological behavior of hydrogels was investigated using variety of parameters. Interestingly, GG-AA hydrogels exhibited around 99 % antibacterial activity against multidrug-resistant bacteria. According to the findings of this study, these novel hydrogels may have immense potential in the food and biomedical sectors.

Dipeptide-polysaccharides hydrogels through co-assembly.

Self-assembling dipeptide hydrogels are attracting attention in food, materials, and biomedicine. However, there are still limitations such as weak hydrogel properties. Herein, we introduced two types of polysaccharides (Arabic gum and citrus pectin) into an alkyl-chain modified dipeptide (C13-tryptophan-tyrosine (C13-WY)) to generate co-assembled C13-WY-arabic gum and C13-WY-pectin hydrogels. The co-assembled hydrogels exhibited enhanced mechanical properties and stability. The G' value of C13-WY-arabic gum and C13-WY-pectin hydrogels was 3 and 10 times larger than that of C13-WY hydrogel, respectively. The addition of Arabic gum and citrus pectin led to the co-assembly and molecular rearrangement. Moreover, co-assembled hydrogels showed more β-sheet structure and hydrogen bonds. Importantly, the self-/co-assembled hydrogels showed low cytotoxicity. We utilized these hydrogels for the encapsulation of docetaxel and they showed a high embedding rate and slow-release. Our findings provide a novel strategy for the development of stable supramolecular peptide hydrogels with good biocompatibility through simple co-assembly.