Trivalent ion cross-linked pH sensitive alginate-methyl cellulose blend hydrogel beads from aqueous template

Vitamin K (Menadione)-incorporated chitosan/alginate hydrogel as a novel product for periorbital hyperpigmentation

The possibility of controlling periorbital hyperpigmentation disorders is one of the most important research goals in cosmetic preparations. In the current investigation, 1% vitamin K (Vit K) was incorporated into a Chitosan/alginate hydrogel which aimed to increase the dermal delivery and anti-pigmentation effect. The Vit K-hydrogel was evaluated using several different tests, including volume expansion/contraction analysis, differential scanning calorimetry (DSC), scanning electron microscopy (SEM), ultraviolet (UV) absorbance spectroscopy, and attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy. Vit K hydrogel's drug release profile showed a steady increase over time. Furthermore, the modified Vit K hydrogel formulations showed no harmful effects in an in vitro cytotoxicity study. The Vit K hydrogel was tested for dermal irritation on Wistar rats, and the hydrogel was found to be non-irritating. Furthermore, Vit K-hydrogel inhibited melanin formation (31.76 ± 1.14%) and was remarkably higher than free Vit K. In addition, Vit K-hydrogel inhibited L-dopa auto-oxidation to a greater extent (94.80 ± 2.41%) in comparison with Vit K solution (73.95 ± 1.62%). Vit K-hydrogel enhanced percutaneous transport of Vit K, according to in vitro percutaneous absorption findings, suggesting that this innovative formulation may provide new therapeutic options for periorbital hyperpigmentation.

Enhancing the Properties of Self-Healing Gelatin Alginate Hydrogels by Hofmeister Mediated Electrostatic Effect

The cross-linker-free hydrogels have gained attention due to their lack of need for chemically modified polymers, resulting in better biocompatibility. The hydrogel properties can be enhanced by altering physical forces such as electrostatics and H-bonds. Tuning the physical interactions between polymers, salts, and plasticisers can unlock new horizons in material properties. This article examines four different salts and mixtures to determine their impact on gelatin-alginate biomaterial design. Drug release, swelling, and rheological properties are represented using a 3-D plot, and optimum samples are identified. It is concluded that kosmotropes yield better release and swelling results than chaotropes. The physical interactions of these salts with polymers are explained using DLS and FTIR/ATR studies, and these findings are corroborated with release, swelling, and rheological analyses. Another aspect of the biomaterial, self-healing property, is also considered. A 3-D plot is prepared using release kinetics, gel strength, and recovery percentage (three important factors for self-healing hydrogels). Chaotropes are identified as better candidates for self-healing behaviour. However, when considering gel strength, release, and self-healing, kosmotropes are favourable. Hence, different salts can be selected based on the desired application for hydrogels. It is also concluded that electrostatic forces hinder the formation of H-bonds between polymer chains.

Conception of Cellulose/Alginate/Mesalazine microspheres by solvent evaporation technique for drug release: Experimental and theoretical investigations

Preparation of microspheres containing Mesalazine referred to as 5-aminosalicylic acid (5-ASA) for colon targeting drug was carried out using the emulsion solvent evaporation technique. The formulation was based on 5-ASA as the active agent, sodium Alginate (SA) andEthylcellulose (EC) as encapsulating agents, with polyvinyl alcohol (PVA) as emulsifier. The effects ofthe following processing parameters, 5-ASA %, EC:SA ratio and stirring rate on the properties of the resulting products in the form microspheres were considered. The samples were characterized using Optical microscopy, SEM, PXRD, FTIR, TGA, and DTG. In vitro release of 5-ASA from the different batches of microspheres was tested in biologically simulated fluids, (gastric; SGF, pH 1.2 for 2 h), then (intestinal fluid SIF, pH 7.4for 12 h) at 37 °C. The release kinetic results have been treated mathematically relaying on Higuchi's and Korsmeyer-Peppas' models for drug liberation. DOE study was performed to evaluate the interactive effects of variables on the drug entrapment and microparticle sizes. Molecular chemical interactions in structures were optimized using DFT analysis.

Smart stimuli-responsive hydrogels for drug delivery in periodontitis treatment

Periodontitis is a chronic inflammatory disease initiated by pathogenic biofilms and host immunity that damages tooth-supporting tissues, including the gingiva, periodontal ligament and alveolar bone. The physiological functions of the oral cavity, such as saliva secretion and chewing, greatly reduce the residence of therapeutic drugs in the area of a periodontal lesion. In addition, complex and diverse pathogenic mechanisms make effectively treating periodontitis difficult. Therefore, designing advanced local drug delivery systems and rational therapeutic strategies are the basis for successful periodontitis treatment. Hydrogels have attracted considerable interest in the field of periodontitis treatment due to their biocompatibility, biodegradability and convenient administration to the periodontal pocket. In recent years, the focus of hydrogel research has shifted to smart stimuli-responsive hydrogels, which can undergo flexible sol-gel transitions in situ and control drug release in response to stimulation by temperature, light, pH, ROS, glucose, or enzymes. In this review, we systematically introduce the development and rational design of emerging smart stimuli-responsive hydrogels for periodontitis treatment. We also discuss the state-of-the-art therapeutic strategies of smart hydrogels based on the pathogenesis of periodontitis. Additionally, the challenges and future research directions of smart hydrogels for periodontitis treatment are discussed from the perspective of developing efficient hydrogel delivery systems and potential clinical applications.

Development of soy protein isolate/sodium carboxymethyl cellulose synbiotic microgels by double crosslinking with transglutaminase and aluminum chloride for delivery system of Lactobacillus acidophilus

This study was carried out to develop soy protein isolate (SPI)/sodium carboxymethyl cellulose (NaCMC) synbiotic microgels by applying a double-crosslinking technique using transglutaminase and different concentrations of AlCl₃ (0, 6, 7, 8 %) and also by adding Lactobacillus acidophilus (L. acidophilus) and pectic oligosaccharide. Synbiotic microgels crosslinked using 8 % AlCl₃ (SPI/NaCMC-Al³⁺₈ microgels) showed the highest encapsulation efficiency (92 %). The double-crosslinked microgels exhibited a smooth surface as proved by SEM. FT-IR, XRD, and DSC analyses showed the possible interaction within matrices and demonstrated the higher thermal stability of synbiotic microgels prepared using a higher concentration of AlCl₃. All in all, after exposure to simulated digestion fluid, heat treatment (72 °C, 15 s), and refrigerated storage, more cells in double-crosslinked microgels survived compared to single-crosslinked microgels. In particular, probiotic viability was highest in SPI/NaCMC-Al³⁺₈ microgels. These results indicate that the SPI/NaCMC-Al³⁺₈ microgels developed in this study can effectively protect L. acidophilus against the external environment.

An Eco-Friendly Antheraea Pernyi Silk Gland Protein/Sodium Alginate Multiple Network Hydrogel as Potential Drug Release Systems

To improve the versatility of the sodium alginate-loaded bio-hydrogels, Antheraea pernyi silk gland protein/sodium alginate drug-loaded hydrogels were prepared by using an eco-friendly multiple network cross-link technology. Fourier transform infrared (FT-IR) spectroscopy and UV-Vis spectrophotometer were used separately to evaluate the chemical structure and drug release behavior of drug-loaded hydrogels. The antibacterial drug carrier gels were evaluated by using inhibition zone test against the S. aureus and E. coli. The CCK-8 assay was used to assess the biocompatibility of drug loaded hydrogels. The FT-IR results showed that there was a strong interaction within the drug loaded hydrogels, and the ASGP was beneficial to enhance the interaction within the drug loaded hydrogels. UV-Vis spectrophotometer results indicated the cumulative release reached 80% within 400 min. Antibacterial bio-hydrogels had a good antibacterial property, especially the antibacterial bio-hydrogels with bacitracin exhibits superior to other antibacterial agents. The drug-loaded bio-hydrogels exhibited the adhesion and proliferation of RSC96 cells and perfected biocompatibility. This provides a new idea for further research and development of tissue-friendly drug-loaded biomaterials.

Green preparation, characterization, evaluation of anti-melanogenesis effect and in vitro/in vivo safety profile of kojic acid hydrogel as skin lightener formulation

The local treatment of kojic acid (KA) as a tyrosinase inhibitor results in inadequate skin absorption and a number of side effects. The current study aims to maximize KA skin delivery. To produce KA-hydrogel, 1% KA was injected into a Chitosan/alginate hydrogel. The impacts of biopolymer proportion on the KA-hydrogel preparations were investigated. Swelling analysis, weight loss analysis, differential scanning calorimetry (DSC), scanning electron microscopy (SEM), UV absorption spectroscopy, attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy were used to evaluate the KA-hydrogel. The swelling percentages of KA-hydrogel increased significantly after 4 h. After two weeks, up to 60% of the primary mass of the KA- hydrogel has been removed. By alternation in biopolymer proportion, the drug release profile of KA-hydrogel demonstrated a sustained pattern. According to the skin absorption experiment, KA-hydrogel had higher skin deposition (25.630 ± 3.350%) than KA-plain gel (5.170 ± 0.340%). Moreover, an in vitro cytotoxicity analysis for the modified KA-hydrogel preparations revealed no cytotoxic effects on HFF cell line (90%). Moreover, KA hydrogel had inhibitory effect on melanin synthesis and are comparable with KA. Furthermore, KA-hydrogel had higher inhibitory effect on L-dopa auto oxidation (94.84 ± 2.41%) in comparison KA solution (73.95 ± 3.28%). Also, the dermal irritation study on Wistar rat revealed that the hydrogel constituent used did not irritate the skin. These results revealed that the KA-hydrogel might be employed as KA local administration, thus opening up new prospects for the therapies of hyperpigmentation problems.

Eco-Friendly Bio-Hydrogels Based on Antheraea Pernyi Silk Gland Protein for Cell and Drug Delivery

The Antheraea Pernyi silk gland protein originates from natural organisms and synthesized by tussah silk glands and has widely potential biomaterial applications due to the superior biocompatibility. This study investigates the Antheraea Pernyi silk gland protein-based drug-loaded bio-hydrogels for bioengineered tissue fabricated by using an eco-friendly method without the harsh extracting process and the usage of toxic chemicals. The drug-loaded bio-hydrogels exhibited a porous structure and interconnected pore walls. The swelling ratio and water absorption of drug-loaded bio-hydrogels were, respectively, above 95% and 1.5 × 10³%. The cumulative release of drug loaded hydrogels all reached more than 90% within 4 h, and this indicates the potential of drug-loaded hydrogels as future drug-carrying biomaterials. RSC96 Schwann cells cultured on drug-loaded hydrogels for 72 h under cell culture medium show no toxic effects and more pro-proliferative effects. The results suggest the suitability of drug-loaded bio-hydrogels as natural biopolymer for the potential in vitro RSC96 cell culture platform and other biomaterial applications.

Development and Evaluation of Thermosensitive Hydrogels with Binary Mixture of Scutellariae baicalensis radix Extract and Chitosan for Periodontal Diseases Treatment

Scutellaria baicalensis root displays anti-inflammatory and antibacterial properties due to the presence of flavonoids, particularly baicalin, baicalein, and wogonin. Our work aimed at developing thermosensitive hydrogels containing a binary mixture of S. baicalensis radix lyophilized extract and chitosan as a novel approach for periodontal diseases treatment. Two types of chitosan were employed in preliminary studies on binary mixtures with S. baicalensis radix lyophilized extract standardized for baicalin, baicalein, and wogonin. Thermosensitive hydrogels were prepared of poloxamer 407, alginate sodium, and cellulose derivatives and evaluated in terms of rheological and mucoadhesive behavior. The presence of chitosan altered the release profile of active compounds but did not affect their in vitro permeation behavior in PAMPA assay. The synergistic effects of S. baicalensis radix lyophilized extract and chitosan toward ferrous ion-chelating activity, inhibition of hyaluronidase, and pathogen growth were observed. The thermosensitive gelling system showed shear-thinning properties, gelation temperature between 25 and 27 °C, and favorable mucoadhesiveness in contact with porcine buccal mucosa, which was enhanced in the presence of binary mixture of S. baicalensis radix extract and chitosan. The release tests showed that baicalin and baicalein were liberated in a prolonged manner with a fast onset from hydrogel formulations.

Shellac Gum/Carrageenan Alginate-Based Core-Shell Systems Containing Peppermint Essential Oil Formulated by Mixture Design Approach

Peppermint essential oil is encapsulated by inverse ionotropic gelation in core–shell systems, composed of alginate (ALG) alone or alginate with shellac gum (SHL) and/or carrageenan (CRG). A mixture design approach is used to evaluate the correlation between the formulation composition and some properties of the final products. Immediately after the preparation, capsules appear rounded with a smooth and homogeneous surface, having a similar particle size ranging from 3.8 mm to 4.5 mm. The drying process, carried out at 40 °C in an oven for 3 h, reduces capsules’ diameters by at least 50% and has a negative impact on the shape of the systems because they lose their regular shape and their external membrane partially collapses. The peppermint essential oil content of dried capsules is between 14.84% and 33.75%. The swelling behaviour of the systems is affected by the composition of their outer shell. When the external membrane is composed of alginate and shellac gum, the capsule ability to swell is lower than that of the systems containing alginate alone. The swelling ratio reaches 31% for alginate capsules but does not exceed 21% if shellac is present. Differently, when the second polymer of the shell is carrageenan, the swelling ability increases as a function of polymer concentration and the swelling ratio reaches 360%. In the case of systems whose outer membrane is a polymeric ternary mixture, the swelling capacity increases or decreases according to the concentrations of the individual polymers. The obtained results suggest that carrageenan could be a useful excipient to increase the swelling behaviour of the systems, while shellac gum makes the system shell more hydrophobic. The use of a mixture design (i.e., the use of ternary diagrams and related calculations), in which each single component is chosen to provide specific properties to the final mixture, could be the right approach to develop improved formulations with a tailored essential oil release profile.

Colorimetric ammonia (NH3) sensor based on an alginate-methylcellulose blend hydrogel and the potential opportunity for the development of a minced pork spoilage indicator

Hydrogels based on alginate and methylcellulose were developed as a colorimetric indicator for monitoring minced pork spoilage. The hydrogel was fabricated by an external gelation method using Ca²⁺ as the crosslinking agent. The pH-sensitive dye bromothymol blue was incorporated into the hydrogel to act as an indicator. The hydrogel's swelling index increased with an increasing ratio of methylcellulose, suggesting that the water uptake capacity is tunable by the polymer composition. The hydrogel's compression strength is directly proportional to the alginate content. The hydrogel indicator demonstrated a color change from orange to yellow (day 6) upon detecting total volatile basic nitrogen (TVB-N) built up in the package during minced pork storage at 4 °C, and the results showed a positive correlation between the color change, TVB-N and pH change of minced pork. This result demonstrated the potential application of the hydrogel as a spoilage indicator in intelligent packaging.

Hydrogel beads-based nanocomposites in novel drug delivery platforms: Recent trends and developments

The present article evaluates the composition and synthesis of hydrogel beads. Hydrogels, owing to their known biocompatibility, are widely used in drug delivery as a host (or drug carrier). Hydrogels, owing to their physical, chemical and biological properties, are popular in many aspects. Hydrogels are crosslinked-hydrophilic polymers and commercialized/synthesized in both natural and synthetic forms. These polymers are compatible with human tissues, therefore can be potentially used for biomedical treatments. Hydrogels in drug delivery offer several points of interest such as sustainability, and sensitivity without any side-effects as compared to traditional methods in this field. Drugs can encapsulate and release continuously into the targets when hydrogels are activated/modified magnetically or by fluorescent materials. It is crucial to develop new crosslinked polymers in terms of "biocompatibility" and "biodegradability" for novel drug delivery platforms. In the event that the accomplishments of the past can be used into the longer terms, it is exceedingly likely that hydrogels with a wide cluster of alluring properties can be synthesized. The current review, offers an updated summary of latest developments in the nanomedicines field as well as nanobased drug delivery systems over broad study of the discovery/ application of nanomaterials in improving both the efficacy of drugs and targeted delivery of them. The challenges/opportunities of nanomedicine in drug delivery also discussed. SCOPE OF THE RESEARCH: Although several reviews have been published in the field of hydrogels, however many of them have just centralized on the general overviews in terms of "synthesis" and "properties". The utilization of hydrogels and hydrogel-based composites in vital applications have been achieved a great interest. In this review, our aim is to recap of the key points in the field of hydrogels such as; a) hydrogel nanocomposites, b) magnetic beads, c) biomedical applications, and d) drug delivery. In the same vein, these outlines will be expanded with emphasizing on the boon of magnetic beads and recent developments in this area.

Development and optimization of Fe3+-crosslinked sodium alginate-methylcellulose semi-interpenetrating polymer network beads for controlled release of ibuprofen

In this study, ionically crosslinked beads of sodium alginate (NaAlg) and methylcellulose (MC) were prepared as semi-interpenetrating polymer networks (semi-IPN) in the size range of 1.97 ± 0.09-1.22 ± 0.13 mm by crosslinking with FeCl₃ and loaded with ibuprofen (IBU), which is a nonsteroidal anti-inflammatory drug. The highest 93.33% entrapment efficiency of IBU was achieved, and the drug release behaviors, mean particle size, and entrapment efficiency of beads were investigated in terms of the polymer composition, a ratio of ibuprofen to polymer, exposure time to crosslinker, and concentration of the crosslinking agent. Semi-IPN formulations prepared were also characterized using Fourier transform infrared (FTIR) spectroscopy, differential scanning calorimetry (DSC), X-ray Diffraction (X-RD), and scanning electron microscopy (SEM). It was observed that IBU-loaded beads displayed better release performance with an increase amount of NaAlg in the structure. Finally, the optimum IBU release was obtained as 93.9% for beads containing 66.7% (w/w) NaAlg, 33.3% (w/w) MC, IBU/polymer ratio of 1/4, FeCl₃ concentration of 0.1 M, and crosslinking time of 90 min. The in vitro release rate was fitted to five empirical equations, and the diffusion exponent n, which indicated that the release mechanism of IBU from beads followed the Anomalous and Case II transport mechanism.

Design and in vitro antibiofilm activity of propolis diffusion-controlled biopolymers

In this study, a novel pH-sensitive hydrogel beads that is based on gelatin/sodium alginate/chitosan (GEL/SA/CS) loaded with propolis ethanolic extracts (PE) were synthesized. The swelling behavior of GEL/SA/CS hydrogel beads was studied in different pH solutions and compared with unloaded CS (GEL/SA) hydrogel beads. The in vitro release studies have been revealed using four different pH (1.3, 5.0, 6.0, and 6.8), a saliva environment (pH 6.8), a simulated gastric fluid (SGF) (pH 1.3), and a simulated intestinal fluid (SIF) (pH 6.8) to simulate the physiological conditions in gastrointestinal (GI) tract. Propolis-loaded hydrogel beads were found to be stable at pH 1.3, 5.0, 6.0, simulated saliva, SGF, and SIF mediums, whereas the beads lose their stability at pH 6.8 buffer solution. Tested microorganisms displayed greater sensitivity to PE-loaded hydrogel beads compared with pure propolis. Contrary to antimicrobial activity results, antibiofilm activity results of PE-loaded GEL/SA and GEL/SA/CS hydrogel beads were found at low levels. According to the obtained results, the propolis-loaded GEL/SA/CS hydrogel beads synthesized within this study can be used in the treatment of GI tract diseases such as oral mucositis, gastric ulcer, ulcerative colitis, and GI cancer, as controlled releasing carriers of propolis.

Formulation and Coating of Alginate and Alginate-Hydroxypropylcellulose Pellets Containing Ranolazine

The formulation and the coating composition of biopolymeric pellets containing ranolazine were studied to improve their technological and biopharmaceutical properties. Eudragit L100 (EU L100) and Eudragit L30 D-55-coated alginate and alginate-hydroxypropylcellulose (HPC) pellets were prepared by ionotropic gelation using 3 concentrations of HPC (0.50%, 0.65%, and 1.00% wt/wt) and applying different percentages (5%, 10%, 20%, and 30% wt/wt) of coating material. The uncoated pellets were regular in shape and had mean diameter between 1490 and 1570 μm. The rate and the entity of the swelling process were affected by the polymeric composition: increasing the HPC concentration, the structure of the pellets became more compact and slowed down the penetration of fluids. Coated alginate-HPC formulations were able to control the drug release at neutral pH: a higher quantity of HPC in the system determined a slower release of the drug. The nature of the coating polymer and the coating level applied affected the drug release in acidic environment: EU L100 gave better performance than Eudragit L30 D-55 and the best coating level was 20%. The pellets containing 0.65% of HPC and coated with 20% EU L100 represented the best formulation, able to limit the drug release in acidic environment and to control it at pH 6.8.

Nasal delivery of analgesic ketorolac tromethamine thermo- and ion-sensitive in situ hydrogels

Ketorolac tromethamine (KT) was potent to treat moderate to moderately severe pains. However, KT solutions for nasal delivery lost quickly from the nasal route. Thermo- and ion-sensitive in-situ hydrogels (ISGs) are appropriate for nasal drug delivery because the intranasal temperature maintains ∼37 °C and nasal fluids consist of plentiful cations. In this study, a novel nasal thermo- and ion-sensitive ISG of KT was prepared with thermo-sensitive poloxamer 407 (P407) and ion-sensitive deacetylated gellan gum (DGG). The optimal formulation of the KT ISG consisted of 3% (w/v) DGG and 18% (w/v) P407 and its viscosity was up to 7.63 Pas at 37 °C. Furthermore, penetration enhancers and bacterial inhibitors were added and their fractions in the ISG were optimized based on transmucosal efficiencies and toxicity on toad pili. Sulfobutyl ether-β-cyclodextrin of 2.5% (w/v) and chlorobutanol of 0.5% (w/v) were chosen as the penetration enhancer and the bacterial inhibitor, respectively. The Fick's diffusion and dissolution of KT could drive it continuous release from the dually sensitive ISG according to the in vitro investigation. Two methods, writhing frequencies induced by acetic acid and latency time of tails retracting from hot water, were used to evaluate the pharmacodynamics of the KT ISG on the mouse models. The writhing frequencies significantly decreased and the latency time of tail retracting was obviously prolonged (p<0.05) for the KT ISG compared to the control. The thermo- and ion-sensitive KT ISG had appropriate gelation temperature, sustained drug release, improved intranasal absorption, obvious pharmacodynamic effect, and negligible nasal ciliotoxicity. It is a promising intranasal analgesic formulation.