Korsmeyer-Peppas Kinetic Model Research Articles

Exploring potential of tobramycin complexes for combating biofilms: In silico and In vitro studies

Nosocomial infections linked to medical implants, wound infections, and cystic fibrosis infections are mostly caused by biofilms linked to Pseudomonas aeruginosa. The development of biofilms on medical equipment continues to a growing health and financial burden with increased the risk of infections and patient morbidity associated with indwelling medical devices. Pseudomonas aeruginosa exhibited high antibiotic resistance, posing challenges for effective treatment of infections associated with medical implants. Therefore, our objective was to adopt a combinatorial approach for formulating antibiotic complexes for maximum eradication of biofilms associated with medical implants.In this study, we optimized the ratio of Tobramycin (TOB) complexes with complexing agents such as sodium bicarbonate (BC), β-cyclodextrin (β-CD), and ethylenediaminetetraacetic acid (EDTA). Further stability and flexibility of the complexes were examined through molecular docking and dynamics. Subculturing and gram staining were performed for the isolation and identification of Pseudomonas aeruginosa. The antibacterial activity was tested using the broth dilution method and well diffusion method to calculate the MIC (minimum inhibitory concentration) against Pseudomonas aeruginosa planktonic cells and biofilms, respectively. The MIC tests indicated that optimised complexes required a concentration of 8 μg/ml to eradicate both planktonic cells as well as biofilms. However, the TOB-BC-(β-CD)-EDTA complex showed lower optical density (OD) compared to other complexes exhibiting better biofilm inhibition. Subsequently a gel formulation using this optimised (TOB-BC-(β-CD)-EDTA) complex that could be applied to medical equipment or potentially converted into a film using different polymer concentrations was developed. The TOB-BC-(β-CD)-EDTA gel formulation was characterized for pH, viscosity, spread-ability, % yield, moisture content, drug content, in-vitro drug diffusion, and antibacterial efficacy assay. Among all batches, F2 demonstrated the highest % drug diffusion after 24 hours and fit well to the Korsmeyer-Peppas kinetic model. The viscosity of the F2 batch remained within acceptable limits and was stable at 40 ± 0.5 ºC and 75.0 ± 5% RH. The gel efficiently delivered antimicrobial drugs to bacteria within biofilms. In conclusion, tobramycin complex gel showed promising potential for addressing infections related to biofilms on medical implants.

Release of selected nutrients from polymer-coated fertilisers in the soil environment

The aim of the study was to evaluate the release of NH4-N and PO4-P from polymer-coated fertilisers in the soil environment, and to analyse their impact on pH and conductivity of the soil leachates. In this investigation mineral NPK(S) 6-20-30(7) fertiliser (as a starting material), commercial, controlled-release OsmocoteTM fertiliser (as a reference material) and four polymer-coated fertilisers have been used. Biodegradable polybutylene(succinate-co- dilinoleate), polyethylene(succinate-co-terepftalate) and chitosan have been used as coating materials. The experiments were conducted in the laboratory conditions, in PVC columns filled with air-dry soil. The nutrients release from the investigated materials was explained based on the diffusion mechanism and it was interpreted with the use of the Korsmeyer–Peppas kinetic model. Two mechanisms dominate in the release process of nutrients: the mechanism based on quasi-Fickian diffusion and non-Fickian (anomalous case) mechanism. The largest changes of pH and electrical conductivity (EC) of soil leachates occurred in the initial period of research for all tested fertilisers (pH: 9.5–20.3% – loamy sand (S1) 7.9–20.6% – sandy loam (S2); EC: 438–1667% – S1, 771–1509% – S2). The polymer coating significantly reduces the nutrient release from the fertiliser core. The size of these changes depends on the type and thickness of the polymer layer and the physicochemical properties of the soils.

Sodium Triphosphate Effect on Encapsulation of Vitamin B<sub>6</sub> into Chitosan-Alginate Nanoparticles and Its <i>In Vitro</i> Drug Release Study

The in-vitro drug release study of vitamin B6 encapsulated into sodium tripolyphosphate crosslinked chitosan-alginate (B6-TCA) nanoparticles aims to determine the effect of sodium tripolyphosphate on the encapsulation efficiency of vitamin B6 and effectiveness of the nanoparticles to release vitamin B6. The focus of this research is synthesizing and characterizing TCA nanoparticles to encapsulate vitamin B6 as an effective delivery system by studying the kinetics release of vitamin B6. The research resulted in the formation of coarse solid powder nanoparticles in yellowish-white color with a nanoparticle size of 22.55 nm. Sodium tripolyphosphate decreased the percentage of encapsulation efficiency in the B6-TCA nanoparticles as its concentration increased. However, the increasing sodium tripolyphosphate causes a slower release of vitamin B6 from nanoparticles. The encapsulation efficiency of vitamin B6 is 82.04%. The optimum composition of B6-TCA nanoparticles ratio is 2:1:1.5:2, where Korsmeyer-Peppas kinetics model suited its better with the Fickian diffusion mechanism of 0.989 and has the smallest reaction rate constant of 0.039 occurred within 6 h.

BioMOF@cellulose Glycerogel Scaffold with Multifold Bioactivity: Perspective in Bone Tissue Repair.

The development of new biomaterials for musculoskeletal tissue repair is currently an important branch in biomedicine research. The approach presented here is centered around the development of a prototypic synthetic glycerogel scaffold for bone regeneration, which simultaneously features therapeutic activity. The main novelty of this work lies in the combination of an open meso and macroporous nanocrystalline cellulose (NCC)-based glycerogel with a fully biocompatible microporous bioMOF system (CaSyr-1) composed of calcium ions and syringic acid. The bioMOF framework is further impregnated with a third bioactive component, i.e., ibuprofen (ibu), to generate a multifold bioactive system. The integrated CaSyr-1(ibu) serves as a reservoir for bioactive compounds delivery, while the NCC scaffold is the proposed matrix for cell ingrowth, proliferation and differentiation. The measured drug delivery profiles, studied in a phosphate-buffered saline solution at 310 K, indicate that the bioactive components are released concurrently with bioMOF dissolution after ca. 30 min following a pseudo-first-order kinetic model. Furthermore, according to the semi-empirical Korsmeyer-Peppas kinetic model, this release is governed by a case-II mechanism, suggesting that the molecular transport is influenced by the relaxation of the NCC matrix. Preliminary in vitro results denote that the initial high concentration of glycerol in the NCC scaffold can be toxic in direct contact with human osteoblasts (HObs). However, when the excess of glycerol is diluted in the system (after the second day of the experiment), the direct and indirect assays confirm full biocompatibility and suitability for HOb proliferation.

5-Fluorouracil adsorption on graphene oxide-amine modified graphene oxide/hydroxyapatite composite for drug delivery applications: Optimization and release kinetics studies

The present study focused on investigation of graphene oxide/hydroxyapatite (GO/HAp) and amine modified graphene oxide/hydroxyapatite (GO-NH2/HAp) composites as potential drug carrier agents for 5-Fluorouracil (5-FU). Incorporation of 5-Fluorouracil drug was performed via adsorption through π-π interactions and electrostatic attractions. Modification of graphene oxide was performed for the production of amine modified graphene oxide/hydroxyapatite composite with the intention of enhancing adsorption performance. The X-Ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), Thermogravimetric Analysis (TGA) and zeta potential/particle size analysis were performed for particle characterization while Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM) analysis were used to analyze detailed morphological properties. Experimental design studies were followed out in order to determine the effect of adsorption parameters including graphene oxide amount, pH and initial drug concentration on 5-Fluorouracil adsorption behavior. Adsorption isotherms of both composites with unmodified and modified GO were best fitted to Freundlich model with R2 values of 0.9616 and 0.9682 respectively. The maximum adsorption capacities (qm) were calculated as 47.3 mg/g and 18.4 for graphene oxide/hydroxyapatite and amine modified graphene oxide/hydroxyapatite composites respectively at pH 2.0. The highest adsorption percentage was obtained for amine modified graphene oxide/hydroxyapatite composite as 40.87 % at pH 2.0 condition. In vitro release kinetic studies revealed that compliance with Higuchi and Korsmeyer-Peppas kinetic models were observed for graphene oxide/hydroxyapatite, whereas zero order and Korsmeyer-Peppas kinetic models pointed out as the well-fitted model for amine modified graphene oxide/hydroxyapatite composite. The release period of 5-FU drug from all composites were continued up to 8–10 h in physiological conditions (pH 7.4, 37 °C) indicating an achieved controlled release. Based on the overall findings, graphene oxide/hydroxyapatite and amine modified graphene oxide/hydroxyapatite composites could be suggested as a potential drug delivery agent for 5-FU in clinical applications.

Phycocyanin-Loaded Alginate-Based Hydrogel Synthesis and Characterization.

Phycocyanin was extracted from Spirulina platensis using conventional extraction (CE), direct ultrasonic-assisted extraction (direct UAE), indirect ultrasonic-assisted extraction (indirect UAE), and microwave-assisted extraction (MAE) methods at different temperatures, extraction intervals, stirring rate, and power intensities while maintaining the same algae to solvent ratio (1:15 w/v). The optimization of the extraction parameters indicated that the direct UAE yielded the highest phycocyanin concentration (29.31 ± 0.33 mg/mL) and antioxidant activity (23.6 ± 0.56 mg TE/g algae), while MAE achieved the highest purity (Rp = 0.5 ± 0.002). Based on the RP value, phycocyanin extract obtained by MAE (1:15 w/v algae to solvent ratio, 40 min, 40 °C, and 900 rpm) was selected as active compound in an alginate-based hydrogel formulation designed as potential wound dressings. Phycocyanin extracts and loaded hydrogels were characterized by FT-IR analysis. SEM analysis confirmed a porous structure for both blank and phycocyanin loaded hydrogels, while the mechanical properties remained approximately unchanged in the presence of phycocyanin. Phycocyanin release kinetics was investigated at two pH values using Zero-order, First-order, Higuchi, and Korsmeyer-Peppas kinetics models. The Higuchi model best fitted the experimental results. The R2 value at higher pH was nearly 1, indicating a superior fit compared with lower pH values.

A pH-Responsive Hydrogel for the Oral Delivery of Ursolic Acid: A Pentacyclic Triterpenoid Phytochemical.

In this study, poly(HEMA-PEGxMEM-IA) hydrogels were prepared by radical copolymerization of poly(ethylene glycol) methyl ether methacrylate (PEGxMEM), 2-hydroxyethyl methacrylate (HEMA), and itaconic acid (IA). The reaction was carried out in ethanolic solution using N,N'-methylenebisacrylamide (MBA) as a crosslinking agent and 1-hydroxycyclohexyl phenyl ketone (HCPK) as a photo-initiator. The poly(HEMA-PEGxMEM-IA) hydrogels (HGx) were evaluated as a delivery system for ursolic acid (UA), a phytochemical extracted from the plant Clinopodium revolutum, "flor de arena". The hydrogels were characterized by Fourier-transform infrared spectroscopy (FTIR-ATR), Raman spectroscopy, X-Ray diffraction (XRD), thermogravimetric analysis (TGA), and scanning electron microscopy (SEM). The swelling behavior was studied in buffer solutions from pH 2 to 10, specifically at pH 2.2 (gastric environment) and 7.4 (intestinal environment). It was found that the hydrogels studied showed sensitivity to pH. At pH 2.2, the degree of swelling for HG5 and HG9 hydrogels was 0.45 and 0.93 (g water/g hydrogel), respectively. At pH 7.4, the degree of swelling for HG5 and HG9 hydrogels was 1.97 and 2.64 (g water/g hydrogel), respectively. The SEM images show the variation in pore size as a function of pH, and the UA crystals in the pores of the hydrogels can also be observed. The in vitro UA release data best fit the Korsmeyer-Peppas kinetic model and the diffusion exponent indicates that the release mechanism is governed by Fickian diffusion.

Synthesis of thiomer/nanoclay nanocomposites as a potential drug carrier: Evaluation of mucoadhesive and controlled release properties

Novel thiomer/nanoclay nanocomposites based on a thiomer and montmorillonite (MMT) were prepared in order to obtain a mucoadhesive material with controlled release properties for its potential use as drug carrier. The thiomer was synthesized by immobilization of L-cysteine in alginate mediated by carbodiimide reaction and further characterized by FT-IR and Ellman's reaction. Nanocomposites with growing concentrations of thiomer and MMT were prepared and analyzed by XRD, TGA and TEM. Rheological behavior of nanocomposite in contact with mucin and intestinal mucus were studied as in vitro and in situ mucoadhesion approach, showing until ∼10-fold increasing in the complex viscosity and ∼27-fold in elastic modulus when the amount of thiomer is increased. Higuchi and Korsmeyer-Peppas kinetic models were evaluated in order to study the release of deltamethrin from nanocomposite films. Release profiles showed a retard in the migration of the drug influenced by the amount of MMT (P < 0.05). Diffusion coefficient (D) showed a significant decrease (P < 0.0001) when concentration of MMT is increased reaching D = 4.18 × 10–7 m2 h–1, which resulted ∼7-fold lower in comparison with formulation without MMT. This hybrid nanocomposite can be projected as a potential mucoadhesive drug carrier with controlled release properties.

Effects of quaternization sites and crossing methods on the slow-release and antibacterial effects of hydroxypropyltrimethyl ammonium chloride chitosan/dialdehyde chitosan-based film

In this study, the active food packaging film were prepared using hydroxypropyltrimethyl ammonium chloride chitosan with different substitution sites (O-HACC & N-HACC) and dialdehyde chitosan (DCS) grafted with protocatechuic acid (PA). To explore the effect of chitosan quaternization positions and crosslinking approaches on the slow-release and antibacterial properties, the double-crosslinked film were fabricated through the self-coupling reaction of PA and Schiff base reaction between amino groups on HACC and aldehyde groups on DCS. The HACC/DCS-based film exhibited stable porous three-dimensional networks with high nisin loading ratios (>90 %). With the participation of the catechol-catechol structure, the dense double-crosslinked film effectively restricted the diffusion of the water molecules, resulting in excellent slow-release properties fitting with the Korsmeyer-Peppas kinetic model. Especially, O-HACC/PA-g-DCS film, which had more reaction sites for Schiff base crosslinking than N-HACC, exhibited the equilibrium swelling ratio of 800 % at 60 h and could sustainably release nisin via non-Fickian diffusion behavior until 48 h. Moreover, the HACC/DCS-based double-crosslinked film performed good long-time antibacterial activity and preservation effects on salmon. On the 10th day of storage, the TVBN of N-HACC/PA-g-DCS and O-HACC/PA-g-DCS groups were only 28.26 ± 1.93 and 29.06 ± 1.68 mg/100 g and still lower than the thresholds.

Dual-function starch aerogels: Nutraceutical carriers for iron and folic acid delivery

Iron and folic acid are especially important in pregnancy, where supplementation is often the only path to prevent anemia. Despite the available commercial solutions, the challenges of enhancing nutrient absorption and reducing side effects foster the search for novel approaches. In this work, freeze-dried starch aerogels were developed to act as nutraceutical carriers for co-delivery and tested under simulated digestion conditions. Iron and folic acid were loaded into starch gels, both separately and mixed. Iron presented a faster release than folic acid in intestinal conditions, reaching 75–80 % after 10 and 90 min, respectively. Molecular modeling suggests that folic acid interacts with amylose agglomerates in water by hydrogen bonds, probably delaying its release. Co-delivery of these nutraceuticals seems to not affect the release behavior. The Korsmeyer-Peppas kinetic model fits well to all release profiles. The proposed starch aerogel is a promising solution and further development can increase its competitiveness against conventional supplements.

D-α-tocopheryl polyethylene glycol succinate-decorated dual drug-loaded lipidic nanocarriers: A strategic approach for targeting lymphatic uptake and p-gp efflux modulation to enhance oral bioavailability in HIV-1 viral reservoirs

The toxicity potential and inadequate bioavailability of antiretroviral therapy restrict their effectiveness in completely eradicating HIV-1 from viral reservoirs, as the drugs encounter difficulties in accessing these reservoirs. This study presents a combinatorial d-α-tocopheryl polyethylene glycol succinate (TPGS)-decorated nano-structured lipid carrier of Etravirine (ETR) and Darunavir Ethanolate (DRVE) that was formulated, optimized, and characterized to achieve synergistic effects against HIV-1 infection. The effectiveness of the combinatorial approach was evaluated by in silico studies, and their docking score and free binding energy showed that both drugs demonstrate synergistic effects against their respective enzymes. The cellular research of ED (ETR and DRVE) in TMZ-b1 cell lines also showed that the best ratio of ETR and DRVE (1:6.5 μg/mL) produced a combined effect. The formulation, termed ED-TPGS-NLCs, underwent optimization using central composite rotational design (CCRD) through a modified emulsification process, followed by characterization based on globule size, polydispersity index (PDI), percentage entrapment efficiency, percentage drug loading, and transmission electron microscopy (TEM) analysis. In vitro release studies demonstrated a notable improvement of drug release from the optimized lipid nanosystem, conforming to the Korsmeyer-Peppas kinetics model. Besides, the in-vitro studies, the intestinal permeation enhancement study, the intestinal depth analysis, and the pharmacokinetic assessment of the optimized formulation in Wistar rats were performed to improve permeation and increase plasma drug concentration. ED-TPGS-NLCs also stopped HIV-1 infection in TMZ-b1 cell lines by 50 %, and the lowest concentration needed to do this was about 58 times lower than purified ED suspension. These studies ensure that ED-TPGS-NLCs were taken up due to the formation of chylomicrons and inhibit the p-gp efflux system by TPGS and solutol to inhibit the first-pass hepatic metabolism, which helps to improve the intestinal permeation and enhance plasma drug concentration, leading to enhanced oral bioavailability of ED. Hence, the improved bioavailability of ED in the nanoformulation also enhanced the anti-retroviral efficacy and improved the safety margins of ED-TPGS-NLCs. These findings can also reduce the side effects of high doses of antiretroviral drugs.

Antibacterial and Osteogenic Doxycycline Imprinted Bioglass Microspheres to Combat Bone Infection.

Currently, postoperative infection is a significant challenge in bone and dental surgical procedures, demanding the exploration of innovative approaches due to the prevalence of antibiotic-resistant bacteria. This study aims to develop a strategy for controlled and smart antibiotic release while accelerating osteogenesis to expedite bone healing. In this regard, temperature-responsive doxycycline (DOX) imprinted bioglass microspheres (BGMs) were synthesized. Following the formation of chitosan-modified BGMs, poly N-isopropylacrylamide (pNIPAm) was used for surface imprinting of DOX. The temperature-responsive molecularly imprinted polymers (MIPs) exhibited pH and temperature dual-responsive adsorption and controlled-release properties for DOX. The temperature-responsive MIP was optimized by investigating the molar ratio of N,N'-methylene bis(acrylamide) (MBA, the cross-linker) to NIPAm. Our results demonstrated that the MIPs showed superior adsorption capacity (96.85 mg/g at 35 °C, pH = 7) than nonimprinted polymers (NIPs) and manifested a favorable selectivity toward DOX. The adsorption behavior of DOX on the MIPs fit well with the Langmuir model and the pseudo-second-order kinetic model. Drug release studies demonstrated a controlled release of DOX due to imprinted cavities, which were fitted with the Korsmeyer-Peppas kinetic model. DOX-imprinted BGMs also revealed comparable antibacterial effects against Staphylococcus aureus and Escherichia coli to the DOX (control). In addition, MIPs promoted viability and osteogenic differentiation of MG63 osteoblast-like cells. Overall, the findings demonstrate the significant potential of DOX-imprinted BGMs for use in bone defects. Nonetheless, further in vitro investigations and subsequent in vivo experiments are warranted to advance this research.

Optimization, characterization and evaluation of sodium alginate nanoparticles for Ganoderic acid DM encapsulation: Inhibitory activity on tyrosinase activity and melanin formation

The efficacy of nanoencapsulation as a technology for enhancing the solubility of active substances has been demonstrated. In this particular investigation, Ganoderic acid DM (GA-DM) was encapsulated within sodium alginate nanoparticles (NPs) using the ionic crosslinking method. The confirmation of the successful loading of GA-DM was ascertained through the analysis of Fourier transform infrared spectrum (FTIR). Empirical evidence derived from the examination of scanning electron microscope (SEM) images, transmission electron microscope (TEM) images, atomic force microscope (AFM) images, and dynamic light scattering (DLS) demonstrated a regular distribution and spherical morphology, with an average particle size of approximately 133 nm. The investigation yielded an encapsulation efficiency of 95.27 ± 0.11 % and a drug loading efficiency of 21.17 ± 0.02 % for the prepared sample. The release kinetics of SGPN was fitted with the Korsmeyer-Peppas kinetic model corresponding to diffusion-controlled release. The incorporation of GA-DM into sodium alginate nanocarriers exhibited a mitigating effect on the cytotoxicity of HaCat and B16, while also demonstrating inhibitory properties against tyrosinase activity and melanin formation.

Designing of tragacanth gum-poly(2-(methacryloyloxy) ethyl] dimethyl-(3-sulfopropyl) ammonium hydroxide) and poly(acrylamide) based hydrogels for drug delivery and wound dressing applications

Bioactive tragacanth gum (TG) was functionalized by covalent crosslinking of poly[2-(methacryloyloxy) ethyl] dimethyl-(3-sulfopropyl) ammonium hydroxide (PMEDSAH) to design network structure in form of hydrogel wound dressings (HWD). These copolymers were encapsulated with antibiotic drug vancomycin to enhance wound healing potential of the dressings. The copolymers were characterized by SEM, AFM, FTIR, 13C NMR, XRD, and TGA-DSC analysis. SEM demonstrated uneven heterogeneous morphology and AFM revealed rough surface of copolymer. Inclusion of synthetic component into HD was confirmed by FTIR and 13C NMR. Hydrogel dressings absorbed 8.49 ​± ​1.03 ​g/g simulated wound fluid and exhibited non-hemolytic (3.7 ​± ​0.02 % hemolytic potential) and antioxidant (37.42 ​± ​1.54 ​% free radical scavenging in DPPH assay) properties. Polymers required 35.0 ​± ​5.0 ​mN detachment force to get it detach from the mucosal surface during mucoadhesive test. Tensile strength was found to be 1.88 ​± ​0.13 ​N/mm2 during mechanical stability test. Hydrogel dressings were permeable to O2/H2O and impermeable to microbes. Release of drug vancomycin occurred through non-Fickian diffusion mechanism and release profile was best described by Korsmeyer-Peppas kinetic model. Overall, these results revealed that these hydrogels could be explored as materials for hydrogel wound dressings.

Kinetic analysis of aroma compound release from Citrus aurantium essential oil-casein-phospholipid-nanocomposites

In this study, Citrus aurantium essential oil encapsulated in casein-phospholipid nanocomposites (CAEO–CS–PL-NCs) was prepared and evaluated for controlled-release capacity of aroma compounds. The particle size of the nanocomposites was strongly influenced by the phospholipid concentration in the nanocomposites. The Avrami and Korsmeyer-Peppas kinetic models were used to analyze the aroma release kinetics of freeze-dried CAEO–CS–PL-NCs (FD-CAEO–CS–PL-NCs) at different temperatures and relative humidities. FD-CAEO–CS–PL-NCs were stored for various times with tea leaves to evaluate their potential for making scented teas. The Avrami kinetic analysis indicated that the release of aroma compounds from FD-CAEO–CS–PL-NCs conformed to diffusion-limited, or first-order kinetics, depending on the temperature and relative humidity. The Korsmeyer-Peppas kinetic analysis indicated that the release of aroma compounds from FD-CAEO–CS–PL-NCs involved three release mechanisms, Fickian diffusion, non-Fickian diffusion and the erosive mechanism. The release mechanism involved varied depending on different conditions and different aroma compounds, and at low temperature and relative humidity effective controlled release of aroma compounds was achieved, resulting from intermolecular interactions with the casein micelles. FD-CAEO–CS–PL-NCs showed significantly sensory scores increasing effect of scented tea. The findings will facilitate future developments in the formulation of scented teas, by incorporating aromatic essential oils from fruits and flowers, in the form of essential oil-casein-phospholipid nanocomposites.

Polydimethylsiloxane Organic-Inorganic Composite Drug Reservoir with Gliclazide.

A novel organic-inorganic gliclazide-loaded composite bead was developed by an ionic gelation process using acidified CaCl2, chitosan and tetraethylorthosilicate (TEOS) as a crosslinker. The beads were manufactured by crosslinking an inorganic silicone elastomer (-OH terminated polydimethylsiloxane, PDMS) with TEOS at different ratios before grafting onto an organic backbone (Na-alginate) using a 32 factorial experimental design. Gliclazide's encapsulation efficiency (EE%) and drug release over 8 h (% DR 8 h) were set as dependent responses for the optimisation of a pharmaceutical formula (herein referred to as 'G op') by response surface methodology. EE % and %DR 8 h of G op were 93.48% ± 0.19 and 70.29% ± 0.18, respectively. G op exhibited a controlled release of gliclazide that follows the Korsmeyer-Peppas kinetic model (R2 = 0.95) with super case II transport and pH-dependent swelling behaviour. In vitro testing of G op showed 92.17% ± 1.18 cell viability upon testing on C2C12 myoblasts, indicating the compatibility of this novel biomaterial platform with skeletal muscle drug delivery.

PH-responsive release of ciprofloxacin hydrochloride from micro-, nano-, and functionalized nanocellulose

This research evaluated pH-responsive release characteristics for the drug (ciprofloxacin hydrochloride) from micro-, nano-, and functionalized cellulose forms. Nanocrystalline cellulose (NCC) was prepared from microcrystalline cellulose (MCC) by sulfuric acid hydrolysis. The aldehyde (–CHO) groups were introduced at the carbon-2 (C-2) and carbon-3 (C-3) positions of glucose moiety of the cellulose network by selective oxidation to form di-aldehyde nanocellulose (DANC). The conversion was validated by chemical, spectroscopic, morphological, and crystallographic analysis. Drug binding capacity (mg/g) of DANC was higher (200.8 mg/g) compared to NCC (138.3 mg/g) and MCC (120.2 mg/g), respectively. The increase in pH from 2.5 to 8.5 enhanced drug release for all the excipients. At pH 2.5, slow release of the drugs was observed. In 6 h, DANC released 44.7 % of the loaded drug at pH 2.5. However, drug release reached equilibrium (84.8 % of loaded drug) within 10 min at pH 8.5. The release kinetics at acidic pH were validated using zero-order, first-order, Higuchi, and Korsmeyer-Peppas kinetics models. Higuchi and Korsmeyer–Peppas' kinetic models interpreted drug release phenomena with a good fit. This implies that diffusion, dissolution, swelling, and slight erosion contribute to drug release. The results suggest that selective functionalization can be applied to cellulose for its potential applications in pH-responsive drug delivery, and therefore, the functionalized cellulose deserves immediate attention.

Evaluating physiochemical characteristics of tragacanth gum-gelatin network hydrogels designed through graft copolymerization technique

The present work deals with the evaluation of the physiochemical and biomedical properties of hydrogels derived from copolymerization of tragacanth gum (TG) and gelatin for use in drug delivery (DD) applications. Copolymers were characterized by field emission-scanning electron micrographs (FE-SEM), electron dispersion X-ray analysis (EDAX), Fourier transform infrared spectroscopy (FTIR), 13C-nuclear magnetic resonance (NMR), thermo-gravimetric analysis (TGA), differential scanning calorimetry (DSC) and X-ray diffraction (XRD) analysis. FE-SEM revealed heterogeneous morphology and XRD analysis demonstrated an amorphous nature with short range pattern of polymer chains within the copolymers. The release of the drug ofloxacin occurred through a non-Fickian diffusion mechanism and the release profile was best described by the Korsmeyer-Peppas kinetic model. The hydrogels exhibited blood compatibility and demonstrated a thrombogenicity value of 75.63 ± 1.98 % during polymer-blood interactions. Polymers revealed mucoadhesive character during polymer-mucous membrane interactions and required 119 ± 8.54 mN detachment forces to detach from the biological membrane. The copolymers illustrated the antioxidant properties as evidenced by 2, 2′-diphenylpicrylhydrazyl (DPPH) assay which demonstrated a 65.71 ± 3.68 % free radical inhibition. Swelling properties analysis demonstrated that by change in monomer and cross linker content during the reaction increased the crosslinking of the network. These results suggest that the pore size of network hydrogels could be controlled as per the requirement of DD systems. The copolymers were prepared at optimized reaction conditions using 14.54 × 10−1 molL−1 of acrylic acid monomer and 25.0 × 10−3 molL−1 of crosslinker NNMBA. The optimized hydrogels exhibited a crosslink density of 2.227 × 10−4 molcm−3 and a mesh size of 7.966 nm. Additionally, the molecular weight between two neighboring crosslinks in the hydrogels was determined to be 5332.209 gmol−1.The results indicated that the combination of protein-polysaccharide has led to the development of hydrogels suitable for potential applications in sustained drug delivery.

NIR-triggered drug delivery system based on tungsten disulfide nanosheets coated pH/temperature responsive polymer for controlled delivery of palbociclib: Release kinetics models

BackgroundPolymers that respond to changes in ambient conditions, such as physiological pH and temperature, have garnered increasing interest in the realm of drug delivery systems. In this study, a novel pH and temperature dual-responsive carrier was prepared for palbociclib delivery. MethodsThe tungsten disulfide nanosheets were functionalized with allyl glycidyl ether, allyl alcohol, and N-vinylcaprolactam, and then grafted with 2, 3-diaminopyridine. The in-vitro drug release was studied in simulated cancer (pH=5.6) and blood (pH=7.4) fluids at different temperatures. Significant FindingsThe in-vitro drug release test showed better release behavior at high temperatures in simulated cancer fluid compared to lower temperatures in simulated blood fluid, releasing about 87.53% of the entrapped drug within 6 h at 45 °C in simulated cancer fluid. The drug release shown the best fitting with the Korsmeyer-Peppas kinetic model. When the near-infrared laser irradiation was applied for 15 min, the drug release from the nanocarrier was three times higher than that without the laser irradiation. The maximum sorption capacity of the drug was achieved at approximately 79.04 mg g−1 at pH=8 for 45 min at 25 °C. The sorption procedure was found to follow the Langmuir isotherm and a pseudo-2nd-order kinetic model quite well.

3D-Printed Chitosan-Based Scaffolds with Scutellariae baicalensis Extract for Dental Applications.

The plant material Scutellariae baicalensis radix, which is rich in flavones (baicalin), possesses antibacterial, antifungal, antioxidant, and anti-inflammatory properties. This work aimed to develop a 3D-printed chitosan-based hydrogel rich in Scutellariae baicalensis extract as an innovative approach for the personalized treatment of periodontal diseases. Chitosan-based hydrogels were prepared, and the printability of the prepared hydrogels was determined. The hydrogel with 2.5% w/v of high molecular-weight chitosan (CS), 2% w/v gelatin (Gel), and 10% w/w of extract (Ex) presented the best printability, producing smooth and uniform scaffolds. It was proved that the CS/Gel/Ex hydrogel was stabilized by hydrogen bonds and remained in amorphous dispersion in the 3D-printed structures (confirmed by ATR-FTIR and XRPD). Due to the amorphization of the active substance, a significant increase in the release of baicalin in vitro was observed. It was demonstrated that there was an initial burst release and a continuous release profile (n = 3). Higuchi kinetic was the most likely baicalin release kinetic. The second fit, the Korsmeyer-Peppas kinetics model, showed coupled diffusion of the active ingredient in the hydrated matrix and polymer relaxation regulated release, with n values ranging from 0.45 to 0.89. The anti-inflammatory properties of 3D-printed scaffolds were assessed as the ability to inhibit the activity of the hyaluronidase enzyme. Activity was assessed as IC50 = 63.57 ± 4.98 mg hydrogel/mL (n = 6). Cytotoxicity tests demonstrated the biocompatibility of the material. After 24 h of exposure to the 2.5CS/2Gel/10Ex scaffold, fibroblasts migrated toward the scratch, closed the "wound" by 97.1%, and significantly accelerated the wound healing process. The results render the 3D-printed CS/Gel/extract scaffolds as potential candidates for treating periodontal diseases.