Periodontitis is a globally prevalent chronic inflammatory disease that leads to periodontal pocket formation and eventually destroys tooth-supporting structures. Hence, the drastic increase in dental implants for periodontitis has become a severe clinical issue. Injectable hydrogel based on extracellular matrix (ECM) is highly biocompatible and tissue-regenerative with tailor-made mechanical properties and high payload capacity for in situ delivery of bioactive molecules to treat periodontitis. This therapeutic tool not only enhances the drug release efficiency and treatment efficacy but also reduces operation time. Nevertheless, it remains challenging to optimize the mechanical properties and intelligent control drug release rate of injectable hydrogels to achieve the highest therapeutic outcome. Literature precedent has shown the modulation of polymer backbones (synthetic polymers, natural polysaccharides, and proteins), crosslinking strategies, other bioactive constituents, and potentially the incorporation of nanomaterials that overall improve the desirable physiochemical and biological performances as well as biodegradability. In this review, we summarize the recent advances in the development, design, and material characterizations of common injectable hydrogels. Furthermore, we highlight cutting-edge representative examples of polysaccharide-, protein- and nanocomposite-based hydrogels that mediate regenerative factors and anti-inflammatory drugs for periodontal regeneration. Finally, we express our perspectives on potential challenges and future development of multifunctional injectable hydrogels for periodontitis.
- Publication type
- Journal Article MeSH
- Review MeSH
PURPOSE OF STUDY: Total joint replacements (TJR) have become the cornerstone of modern orthopedic surgery. A great majority of TJR employs ultrahigh molecular weight polyethylene (UHMWPE) liners. TJR manufacturers use many different types of UHMWPE, which are modified by various combinations of crosslinking, thermal treatment, sterilization and/or addition of biocompatible stabilizers. The UHMWPE modifications are expected to improve the polymer's resistance to oxidative degradation and wear (release of microparticles from the polymer surface). This manuscript provides an objective, non-commercial comparison of current UHMWPE formulations currently employed in total knee replacements. MATERIALS AND METHODS: UHMWPE liners from 21 total knee replacements (TKR) were collected which represent the most implanted liners in the Czech Republic in the period 2020-2021. The UHMWPEs were characterized using several methods: infrared microspectroscopy (IR), non-instrumented and instrumented microindentation hardness testing (MH and MHI), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and solubility measurements. The above-listed methods yielded quite complete information about the structure and properties of each UHMWPE type, including its potential long-term oxidation resistance. RESULTS: For each UHMWPE liner, IR yielded information about immediate oxidative degradation (in the form of oxidation index, OI), level of crosslinking (trans-vinylene index, VI) and crystallinity (CI). The MH and MHI testing gave information about the impact of structure changes on mechanical properties. The remaining methods (DSC, TGA, and solubility measurements) provided additional information regarding the structure changes and resistance to long-term oxidative degradation. Statistical evaluation showed significant differences among the samples as well as interesting correlations among the UHMWPE modifications, structural changes, and mechanical performance. DISCUSSION: Surprisingly enough, UHMWPE materials from different manufacturers showed quite different properties, including the resistance against the long-term oxidative degradation, which is regarded as one of the main reasons of TJR failures. The most promising UHMWPE types were crosslinked materials with biocompatible stabilizers. CONCLUSIONS: Current UHMWPE liners from different manufactures used in total knee replacements exhibit significantly different structure and properties. From the point of view of clinical practice, the traditional UHMWPE types, which contained residual radicals from irradiation and/or gamma sterilization, showed inferior resistance to oxidative degradation and should be avoided. The best properties were observed in modern UHMWPE types, which combined crosslinking, biocompatible stabilizers, and sterilization by ethylenoxide or gas plasma. KEY WORDS: UHMWPE; knee replacements; oxidative degradation; infrared spectroscopy; microhardness.
- MeSH
- Biocompatible Materials chemistry MeSH
- Calorimetry, Differential Scanning MeSH
- Humans MeSH
- Polyethylenes * chemistry MeSH
- Prosthesis Design MeSH
- Knee Prosthesis * MeSH
- Thermogravimetry MeSH
- Materials Testing * methods MeSH
- Arthroplasty, Replacement, Knee * instrumentation methods MeSH
- Check Tag
- Humans MeSH
- Publication type
- English Abstract MeSH
- Journal Article MeSH
- Comparative Study MeSH
Restoring the structures and functions of tissues along with organs in human bodies is a topic gathering attention nowadays. These issues are widely discussed in the context of regenerative medicine. Excipients/delivery systems play a key role in this topic, guaranteeing a positive impact on the effectiveness of the drugs or therapeutic substances supplied. Advances in materials engineering, particularly in the development of hydrogel biomaterials, have influenced the idea of creating an innovative material that could serve as a carrier for active substances while ensuring biocompatibility and meeting all the stringent requirements imposed on medical materials. This work presents the preparation of a natural polymeric material based on pullulan modified with silymarin, which belongs to the group of flavonoids and derives from a plant called Silybum marianum. Under UV light, matrices with a previously prepared composition were crosslinked. Before proceeding to the next stage of the research, the purity of the composition of the matrices was checked using Fourier-transform infrared (FT-IR) spectroscopy. Incubation tests lasting 19 days were carried out using incubation fluids such as simulated body fluid (SBF), Ringer's solution, and artificial saliva. Changes in pH, electrolytic conductivity, and weight were observed and then used to determine the sorption capacity. During incubation, SBF proved to be the most stable fluid, with a pH level of 7.6-7.8. Sorption tests showed a high sorption capacity of samples incubated in both Ringer's solution and artificial saliva (approximately 350%) and SBF (approximately 300%). After incubation, the surface morphology was analyzed using an optical microscope for samples demonstrating the greatest changes over time. The active substance, silymarin, was released using a water bath, and then the antioxidant capacity was determined using the Folin-Ciocâlteu test. The tests carried out proved that the material produced is active and harmless, which was shown by the incubation analysis. The continuous release of the active ingredient increases the biological value of the biomaterial. The material requires further research, including a more detailed assessment of its balance; however, it demonstrates promising potential for further experiments.
- MeSH
- Glucans * chemistry MeSH
- Hydrogen-Ion Concentration MeSH
- Drug Delivery Systems methods MeSH
- Humans MeSH
- Drug Carriers * chemistry MeSH
- Polyethylene Glycols * chemistry MeSH
- Silymarin * chemistry MeSH
- Spectroscopy, Fourier Transform Infrared MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
This article presents a method for producing hydrogel dressings using high methylated pectin from apples or citrus, doped with the antiseptic agent, octenidine dihydrochloride. Octenidine was incorporated in-situ during the polymer crosslinking. The pectins were characterized by their varying molecular weight characteristics, monosaccharide composition, and degree of esterification (DE). The study assessed the feasibility of producing biologically active hydrogels with pectin and delved into how the polymer's characteristics affect the properties of the resulting dressings. The structure evaluation of hydrogel materials showed interactions between individual components of the system and their dependence on the type of used pectin. Both the antimicrobial properties and cytotoxicity of the dressings were evaluated. The results suggest that the primary determinants of the functional attributes of the hydrogels are the molecular weight characteristics and the DE of the pectin. As these values rise, there is an increase in polymer-polymer interactions, overshadowing polymer-additive interactions. This intensification strengthens the mechanical and thermal stability of the hydrogels and enhances the release of active components into the surrounding environment. Biological evaluations demonstrated the ability of octenidine to be released from the dressings and effectively inhibit the growth of microbial pathogens.
- MeSH
- Anti-Infective Agents, Local * chemistry pharmacology MeSH
- Citrus chemistry MeSH
- Hydrogels * chemistry pharmacology MeSH
- Imines * chemistry MeSH
- Humans MeSH
- Malus chemistry MeSH
- Microbial Sensitivity Tests MeSH
- Molecular Weight MeSH
- Bandages * MeSH
- Pectins * chemistry pharmacology MeSH
- Pyridines * chemistry pharmacology MeSH
- Staphylococcus aureus drug effects MeSH
- Animals MeSH
- Check Tag
- Humans MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
Polysaccharides like hyaluronan (HA) and chondroitin sulfate (CS) are native of the brain's extracellular matrix crucial for myelination and brain maturation. Despite extensive research on HA and CS as drug delivery systems (DDS), their high water solubility limits their application as drug carriers. This study introduces an injectable DDS using aldehyde-modified hyaluronic acid (HAOX) hydrogel containing polyelectrolyte complexes (PEC) formed with calcium, gelatin, and either CS or aldehyde-modified CS (CSOX) to deliver minocycline for Multiple Sclerosis therapy. PECs with CSOX enable covalent crosslinking to HAOX, creating immobilized PECs (HAOX_PECOX), while those with CS remain unbound (HAOX_PECS). The in situ forming DDS can be administered via a 20 G needle, with rapid gelation preventing premature leakage. The system integrates into an implanted device for minocycline release through either Fickian or anomalous diffusion, depending on PEC immobilization. HAOX_PECOX reduced burst release by 88 %, with a duration of 127 h for 50 % release. The DDS exhibited an elastic modulus of 3800 Pa and a low swelling ratio (0-1 %), enabling precise control of minocycline release kinetics. Released minocycline reduced IL-6 secretion in the Whole Blood Monocytes Activation Test, suggesting that DDS formation may not alter the biological activity of the loaded drug.
- MeSH
- Aldehydes chemistry MeSH
- Chondroitin Sulfates * chemistry MeSH
- Hydrogels * chemistry pharmacology MeSH
- Interleukin-6 metabolism MeSH
- Hyaluronic Acid * chemistry MeSH
- Drug Delivery Systems methods MeSH
- Humans MeSH
- Minocycline * chemistry pharmacology administration & dosage MeSH
- Drug Carriers * chemistry MeSH
- Polyelectrolytes * chemistry MeSH
- Drug Liberation MeSH
- Gelatin * chemistry MeSH
- Animals MeSH
- Check Tag
- Humans MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
Tento příspěvek shrnuje současný stav znalostí o vinylpyrrolidonu, jeho homopolymerech i kopolymerech a zesíťovaných strukturách na jeho bázi, a přináší bohatý přehled různých aplikací se zvláštním zaměřením na biomedicinu. Uvedena je rovněž stručná historie tohoto materiálu. Jsou popsány metody přípravy a technické parametry jak monomerního N-vinylpyrrolidonu, tak jeho různých polymerů. Důležité údaje jsou uvedeny v tabulkách.
This contribution summarizes the present-state of knowledge on vinylpyrrolidone, its (co)polymers, crosslinked structures based on it, and offers a rich survey of various applications, with a special focus on (bio)medicine. A brief history of this material is also given. Methods of preparation and technical parameters of both vinylpyrrolidone monomer and its various polymers are described. Important data are presented in tables.
- MeSH
- Hydrogels administration & dosage chemistry therapeutic use MeSH
- Povidone-Iodine administration & dosage therapeutic use MeSH
- Drug Delivery Systems MeSH
- Humans MeSH
- Polymerization MeSH
- Polymers chemical synthesis MeSH
- Povidone * administration & dosage chemistry MeSH
- Vinyl Compounds chemistry MeSH
- Check Tag
- Humans MeSH
It is believed that 3D bioprinting will greatly help the field of tissue engineering and regenerative medicine, as live patient cells are incorporated into the material, which directly creates a 3D structure. Thus, this method has potential in many types of human body tissues. Collagen provides an advantage, as it is the most common extracellular matrix present in all kinds of tissues and is, therefore, very natural for cells and the organism. Hydrogels with highly concentrated collagen make it possible to create 3D structures without additional additives to crosslink the polymer, which could negatively affect cell proliferation and viability. This study established a new method for preparing highly concentrated collagen bioinks, which does not negatively affect cell proliferation and viability. The method is based on two successive neutralizations of the prepared hydrogel using the bicarbonate buffering mechanisms of the 2× enhanced culture medium and pH adjustment by adding NaOH. Collagen hydrogel was used in concentrations of 20 and 30 mg/mL dissolved in acetic acid with a concentration of 0.05 and 0.1 wt.%. The bioink preparation process is automated, including colorimetric pH detection and adjustment. The new method was validated using bioprinting and subsequent cultivation of collagen hydrogels with incorporated stromal cells. After 96 h of cultivation, cell proliferation and viability were not statistically significantly reduced.
- Publication type
- Journal Article MeSH
Introduction: The objective of current project was to formulate a system for controlled delivery of Tramadol HCl (TRD), an opioid analgesic used in the treatment of moderate to severe pain. Methods: For this purpose, a pH responsive AvT-co-poly hydrogel network was formulated through free radical polymerization by incorporating natural polymers i.e., aloe vera gel and tamarind gum, monomer and crosslinker. Formulated hydrogels were loaded with Tramadol HCl (TRD) and evaluated for percent drug loading, sol-gel fraction, dynamic and equilibrium swelling, morphological characteristics, structural features and in-vitro release of Tramadol HCl. Results and Discussions: Hydrogels were proved to be pH sensitive as remarkable dynamic swelling response ranging within 2.94g/g-10.81g/g was noticed at pH 7.4 as compared to pH 1.2. Percent drug loading was in the range of 70.28%-90.64% for all formulations. Thermal stability and compatibility of hydrogel components were validated by DSC analysis and FTIR spectroscopy. Controlled release pattern of Tramadol HCl from the polymeric network was confirmed as maximum release of 92.22% was observed for over a period of 24 hours at pH 7.4. Moreover, oral toxicity studies were also conducted in rabbits to investigate the safety of hydrogels. No evidence of any toxicity, lesions and degeneration was reported, confirming the biocompatibility and safety of grafted system.
- Publication type
- Journal Article MeSH
Inflammatory bowel disease (IBD) is a relapsing and remitting inflammatory disease affecting millions of people worldwide. The active phase of IBD is characterized by excessive formation of reactive oxygen species (ROS) in the intestinal mucosa, which further accelerates the inflammatory process. A feasible strategy for the IBD treatment is thus breaking the oxidation-inflammation vicious circle by scavenging excessive ROS with the use of a suitable antioxidant. Herein, we have developed a novel hydrogel system for oral administration utilizing sterically hindered amine-based redox polymer (SHARP) incorporating covalently bound antioxidant SHA groups. SHARP was prepared via free-radical polymerization by covalent crosslinking of 2-hydroxyethyl methacrylate (HEMA), poly(ethylene oxide) methyl ether methacrylate (PEGMA) and a SHA-based monomer, N-(2,2,6,6-tetramethyl-piperidin-4-yl)-methacrylamide. The SHARP hydrogel was resistant to hydrolysis and swelled considerably (∼90% water content) under the simulated gastrointestinal tract (GIT) conditions, and exhibited concentration-dependent antioxidant properties in vitro against different ROS. Further, the SHARP hydrogel was found to be non-genotoxic, non-cytotoxic, non-irritating, and non-absorbable from the gastrointestinal tract. Most importantly, SHARP hydrogel exhibited a statistically significant, dose-dependent therapeutic effect in the mice model of dextran sodium sulfate (DSS)-induced acute colitis. Altogether, the obtained results suggest that the SHARP hydrogel strategy holds a great promise with respect to IBD treatment.
- MeSH
- Amines MeSH
- Hydrogels MeSH
- Inflammatory Bowel Diseases * drug therapy MeSH
- Colitis * chemically induced drug therapy MeSH
- Mice MeSH
- Oxidation-Reduction MeSH
- Polymers MeSH
- Animals MeSH
- Check Tag
- Mice MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
A little is known about the link between the macromolecular architecture of dialdehyde polysaccharides (DAPs), their crosslinking capabilities, and the properties of resulting hydrogels. Here, DAPs based on cellulose, dextrin, dextran, and hyaluronate were compared as crosslinkers for poly(vinyl alcohol), PVA. The swelling, network parameters, viscoelastic properties, porosity, and cytotoxicity of PVA/DAP hydrogels were investigated concerning the crosslinker structure, molecular weight, aldehyde group density per macromolecule, and the size of spontaneously formed crosslinker nano-assemblies. Generally, crosslinkers based on linear polysaccharides (cellulose, hyaluronate) performed more reliably, while the presence of branching could be both beneficial (dextran) but also detrimental (dextrin) at lower crosslinker concentrations. For example, the hydrogel swelling differed by up to one-third (600 vs. 400%) and storage modulus even by up to one half (~7000 vs. ~3500 Pa) depending on crosslinker structure and properties. These differences were rationalized by variances in crosslinking modes derived based on obtained data.
- MeSH
- NIH 3T3 Cells MeSH
- Hydrogels chemistry pharmacology MeSH
- Mice MeSH
- Polysaccharides chemistry pharmacology MeSH
- Polyvinyl Alcohol chemistry pharmacology MeSH
- Cross-Linking Reagents chemistry pharmacology MeSH
- Cell Survival drug effects MeSH
- Animals MeSH
- Check Tag
- Mice MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
- Comparative Study MeSH
