Sustained Release Characteristics Research Articles

Enhanced ophthalmic bioavailability and stability of atropine sulfate via sustained release particles using polystyrene sulfonate resin

Atropine sulfate (ATS) eye drops at low concentrations constitute a limited selection for myopia treatment, with challenges such as low ophthalmic bioavailability and inadequate stability. This study proposes a novel strategy by synthesizing ophthalmic sodium polystyrene sulfonate resin (SPSR) characterized by a spherical shape and uniform size for cationic exchange with ATS. The formulation of ATS@SPSR suspension eye drops incorporates xanthan gum and hydroxypropyl methylcellulose (HPMC) as suspending agents. In vitro studies demonstrated that ATS@SPSR suspension eye drops exhibited sustained release characteristics, and tropic acid, its degradation product, remained undetected for 30 days at 40 °C. The ATS levels in the tear fluids and aqueous humor of New Zealand rabbits indicated a significant increase in mean residence time (MRT) and area under the drug concentration–time curve (AUC0-12h) for ATS@SPSR suspension eye drops compared to conventional ATS eye drops. Moreover, safety assessment confirmed the non-irritating nature of ATS@SPSR suspension eye drops in rabbit eyes. In conclusion, the cation-responsive sustained-release ATS@SPSR suspension eye drops enhanced the bioavailability and stability of ATS, offering a promising avenue for myopia treatment.

Preparation and sustained-release of chitosan-alginate bilayer microcapsules containing aromatic compounds with different functional groups

This study investigated the release of aromatic compounds with distinct functional groups within bilayer microcapsules. Bilayer microcapsules of four distinctive core materials (benzyl alcohol, eugenol, cinnamaldehyde, and benzoic acid) were synthesized via freeze-drying. Chitosan (CS) and sodium alginate (ALG) were used as wall materials. CS concentration, using orthogonal experiments with the loading ratio as a metric. Under optimal conditions, three other types of microcapsules (cinnamic aldehyde, benzoic acid, and benzyl alcohol) were obtained. The four types of microcapsules were characterized using Fourier-transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), transmission electron microscope (TEM), and thermogravimetric analysis (TGA), and their sustained release characteristics were evaluated. The optimal conditions were: CS dosage, 1.2 %; CS-to-eugenol mass ratio, 1:2; and CS-to-ALG mass ratio, 1:1. By comparing the IR spectra of the four types of microcapsules, wall material, and core material, the core materials were revealed to be encapsulated within the wall material. SEM results revealed that the granular protuberances on the surface of the microcapsules were closely aligned and persistent when magnified 2000×. The TEM results indicated that all four microcapsules had a spherical and bilayer structure. The thermal stability and sustained release results showed that the four microcapsules were more resilient and less volatile than the four core materials. The release conformed to first-order kinetics, and the release ratios of the four microcapsules were as follows: benzyl alcohol microcapsules ˃ eugenol microcapsules ˃ cinnamaldehyde microcapsules ˃ benzoic acid microcapsules. The prepared bilayer microcapsules encapsulated four different core materials with good sustained release properties.

Formation, stability, and antimicrobial efficacy of eutectic nanoemulsions containing thymol and glycerin monolaurate

In this study, based on the discovery of thymol/glycerol monolaurate (GML) eutectic solvent, we studied the effect of GML as a multi-functional component (ripening inhibitor and antibacterial agent) on the formation, stability and antibacterial activity of eutectic nanoemulsions, and investigated the preservation of nanoemulsion in fresh pork. These results indicated that the formation of eutectic solvent was due to the hydrogen bonding between thymol and GML in the molten state. And eutectic nanoemulsions prepared with medium GML concentrations (20%, 40%, and 60%) of eutectic solvents as oil phases had small droplet diameters (<150 nm), exhibited sustained-release characteristics, and had excellent physicochemical stability. Moreover, the addition of GML enhanced the antibacterial activity of thymol nanoemulsion against S. aureus. as seen by their ability to inhibit affect formation more effectively. Treatment of fresh pork with optimized eutectic nanoemulsions (40% thymol/60% GML) extended its shelf life during refrigeration, which was mainly attributed to the ability of the encapsulated essential oil to inhibit microbial growth and lipid oxidation. These results provide a novel strategy to control Ostwald ripening and maintain the high antibacterial activity of thymol in nanoemulsion-based delivery systems.

Preparation, structural characterization, and functional attributes of zein-lysozyme-κ-carrageenan ternary nanocomposites for curcumin encapsulation

The low water solubility and inadequate bioavailability of curcumin significantly hinder its broad biological applications in the realms of food and medicine. There is limited information currently available regarding the particle characteristics and functional capabilities of zein-lysozyme-based nanomaterials. Thereby, the primary goal of the current work is to effectively develop innovative zein-lysozyme-κ-carrageenan complex nanocomposites (ZLKC) as a reliable carrier for curcumin encapsulation. As a result, ZLKC nanoparticles showed a smooth spherical nanostructure with improved encapsulation efficiency. Fourier-transform infrared, fluorescence spectroscopy, dissociation assay, and circular dichroism analysis revealed that hydrophobic and electrostatic interactions and hydrogen bonding were pivotal in the construction and durability of these composites. X-ray diffraction examination affirmed the lack of crystallinity in curcumin encapsulated within nanoparticles. The incorporation of κ-carrageenan significantly improved the physicochemical stability of ZLKC nanoparticles in diverse environmental settings. Additionally, ZLKC nanocomposites demonstrated enhanced antioxidant and antimicrobial properties, as well as sustained release characteristics. Therefore, these findings demonstrate the potential application of ZLKC nanocomposites as delivery materials for encapsulating bioactive substances.

New Transferrin Receptor-Targeted Peptide-Doxorubicin Conjugates: Synthesis and In Vitro Antitumor Activity.

Poor selectivity to tumor cells is a major drawback in the clinical application of the antitumor drug doxorubicin (DOX). Peptide-drug conjugates (PDCs) constructed by modifying antitumor drugs with peptide ligands that have high affinity to certain overexpressed receptors in tumor cells are increasingly assessed for their possibility of tumor-selective drug delivery. However, peptide ligands composed of natural L-configuration amino acids have the defects of easy enzymatic degradation and insufficient biological stability. In this study, two new PDCs (LT7-SS-DOX and DT7-SS-DOX) were designed and synthesized by conjugating a transferrin receptor (TfR) peptide ligand LT7 (HAIYPRH) and its retro-inverso analog DT7 (hrpyiah), respectively, with DOX via a disulfide bond linker. Both conjugates exhibited targeted antiproliferative effects on TfR overexpressed tumor cells and little toxicity to TfR low-expressed normal cells compared with free DOX. Moreover, the DT7-SS-DOX conjugate possessed higher serum stability, more sustained reduction-triggered drug release characteristics, and stronger in vitro antiproliferative activity as compared to LT7-SS-DOX. In conclusion, the coupling of antitumor drugs with the DT7 peptide ligand can be used as a promising strategy for the further development of stable and efficient PDCs with the potential to facilitate TfR-targeted drug delivery.

In situ chemoimmunotherapy hydrogel elicits immunogenic cell death and evokes efficient antitumor immune response

BackgroundChemoimmunotherapy has shown promising advantages of eliciting immunogenic cell death and activating anti-tumor immune responses. However, the systemic toxicity of chemotherapy and tumor immunosuppressive microenvironment limit the clinical application.MethodsHere, an injectable sodium alginate hydrogel (ALG) loaded with nanoparticle albumin-bound-paclitaxel (Nab-PTX) and an immunostimulating agent R837 was developed for local administration. Two murine hepatocellular carcinoma and breast cancer models were established. The tumor-bearing mice received the peritumoral injection of R837/Nab-PTX/ALG once a week for two weeks. The antitumor efficacy, the immune response, and the tumor microenvironment were investigated.ResultsThis chemoimmunotherapy hydrogel with sustained-release character was proven to have significant effects on killing tumor cells and inhibiting tumor growth. Peritumoral injection of our hydrogel caused little harm to normal organs and triggered a potent antitumor immune response against both hepatocellular carcinoma and breast cancer. In the tumor microenvironment, enhanced immunogenic cell death induced by the combination of Nab-PTX and R837 resulted in 3.30-fold infiltration of effector memory T cells and upregulation of 20 biological processes related to immune responses.ConclusionsOur strategy provides a novel insight into the combination of chemotherapy and immunotherapy and has the potential for clinical translation.

Active whey protein/hydroxypropyl methylcellulose edible films incorporated with cinnamaldehyde: Characterization, release kinetics and application to Mongolian cheese preservation

Edible films with modulated release of antimicrobial agents are important for food preservation. Herein, antimicrobial edible films were prepared using whey protein (WP) and hydroxypropyl methylcellulose (HM) as polymer matrix materials and cinnamaldehyde (CIN) as antimicrobial agent. The mass ratios of WP and HM were 100/0, 75/25, 50/50, 25/75 and 0/100. The release kinetics of CIN through the film was studied, applying the Fickian model, power law and Weibull model. The films were also characterized by physical and structural characteristics, and antibacterial activity. In comparison to other films, the CIN-loaded film with a WP/HM ratio of 50/50 had better moisture resistance, water vapor barrier properties and mechanical properties. High correlation factors were obtained by fitting the CIN release data with the power law (R2 > 0.96) and Weibull model (R2 > 0.97). The diffusion mechanism of CIN was pseudo-Fickian. The diffusion coefficients (D1 and D2) had a positive linear relationship with the HM ratio, suggesting that a high HM ratio was beneficial to the CIN release. Finally, the WH50-C film was successfully used to preserve Mongolian cheese. This research provides a new perspective on the design of active packaging film with sustained-release characteristics.

Formulation and Evaluation of Moxifloxacin Hydrochloride Loaded Cubosomal Gel for Ocular Delivery

This study aimed to develop and evaluate an ocular, prolonged-release cubogel formulation of moxifloxacin hydrochloride (MX) to treat conjunctivitis. Using glycerol monooleate and poloxamer 407 in varying concentrations, a cubosome containing the antibiotic MX was developed using a top-down approach. Further, by dispersing optimized cubosomes in a cold in-situ gelling system, MX cubogels were prepared. Following Higuchi's release kinetic model, formulations MA4, MA8, MA11, and MA14 released 95.84, 95.77, 97.45, and 97.68% of MX after 12 hours. The in-vitro corneal permeation study showed that the goat cornea absorbed 81% of MX cubogel than conventional formulations. From the results of antibacterial and histopathological studies, the selected formulations were safe for ocular administration. This study concluded that MX cubogel may be a suitable alternative to conventional eye drops due to its increased permeability and sustained release characteristics.&#x0D; Keywords: Conjunctivitis, Cubosome, Glycerol monooleate, Moxifloxacin hydrochloride Poloxamer 407

Preparation of etoposide liposomes for enhancing antitumor efficacy on small cell lung cancer and reducing hematotoxicity of drugs

Etoposide (VP16) is commonly used in the treatment of small cell lung cancer (SCLC) in clinical practice. However, severe adverse reactions such as bone marrow suppression toxicity limit its clinical application. Although several studies on VP16 liposomes were reported, no significant improvement in bone marrow suppression toxicity has been found, and there was a lack of validation of animal models for in vivo antitumor effects. Therefore, we attempted to develop a PEGylated liposomal formulation that effectively encapsulated VP16 (VP16-LPs) and evaluated its therapeutic effect and toxicity at the cellular level and in animal models. First, we optimized the preparation process of VP16-LPs using an orthogonal experimental design and further prepared them into freeze-dried powder to improve storage stability of the product. Results showed that VP16-LPs freeze-dried powder exhibited good dispersibility and stability after redispersion. In addition, compared to marketed VP16 injection, VP16-LPs exhibited sustained drug release characteristics. At the cellular level, VP16-LPs enhanced the cellular uptake of drugs and exhibited strong cytotoxic activity. In animal models, VP16-LPs could target and aggregate in tumors and exhibit a higher anti-tumor effect than VP16-injection after intravenous injection. Most importantly, hematological analysis results showed that VP16-LPs significantly alleviated the bone marrow suppression toxicity of drug. In summary, our study confirmed that PEGylated liposomes could enhance therapeutic efficacy and reduce toxicity of VP16, which demonstrated that VP16-LPs had enormous clinical application potential.

Sustainable approach for nutrient release control in organic fertilisers by using phosphogypsum

ABSTRACT Fertilisers maintain agricultural productivity for world needs, Despite the numerous advantages of controlled release fertilisers (CRFs), production expenses and impacts on the environment and soil quality limit widespread adoption. This research focuses on valorising agro-industrial waste through a biotransformation process (anaerobic and aerobic digestion). The resulting biofertilisers, when associated with phosphogypsum (PG) using the simplex-centroid design, create organo-mineral fertilisers with controlled nutrient release. A balanced formulation with 33.33% of each component (digestate, compost, and phosphogypsum) demonstrates a promising sustainable approach, contributing nutritional elements with exceptional control and sustained release characteristics, all without the previous use of coating materials. This environment-friendly approach accords with the Sustainable Development Goals, particularly 2, 3, 12, and 15.

Plaque‐Specific Adhesive Balloons Coated with Calcium Phosphate Nanoparticles Loaded with Rapamycin for Atherosclerosis Therapy

AbstractDrug‐coated balloons (DCBs), serving as a superior alternative to stents, are at the cutting edge of clinical innovations in atherosclerosis management. Nevertheless, the prevalent high flow rates in arterial vascular result in short drug residence times, significantly compromising DCBs’ therapeutic effectiveness. Drawing inspiration from the mechanisms of vascular calcification, a rapamycin‐loaded calcium phosphate nanoparticle (CaP@Rapa) coating for balloons is pioneered. This coating functions as a potent drug anchor in arteries, facilitating the adhesion of rapamycin to plaques and thereby enhancing the local concentration of the rapamycin. To evaluate its therapeutic efficacy in vivo, the rabbit iliac artery atherosclerosis model is innovatively developed, which authentically mirrors the pathological progression of atherosclerosis in humans. The enhanced localized rapamycin retention, along with its pH‐sensitive sustained release characteristics, culminate in substantial reductions in plaque volume, a decrease in intimal hyperplasia, and mitigation of local inflammation in model rabbits. To further substantiate the translational potential of CaP@Rapa balloons, the research on the pig coronary atherosclerosis model is expanded, which yielded results solidifying the clinical promise of CaP@Rapa balloons. In summary, this research not only offers a more effective and reliable alternative to traditional DCB but also paves the way for further clinical trials.

PCL/Fucoidan nanofiber membrane loaded HP-β-CD/EGC inclusion complexes for food packaging based on self-assembly strategy

In this study, 2-Hydroxypropyl-β-cyclodextrin (HP-β-CD)/Epigallocatechin (EGC) inclusion complexes were prepared by ultrasound-guided, and Polycaprolactone (PCL)/Fucoidan (FD) nanofiber membranes were rapidly prepared by electrospinning technology. The test results showed that the average diameter of the nanofiber film increased from 1429.11 to 1728.12 nm, the water vapor permeability was enhanced, the crystallinity was reduced, and the surface was hydrophilic. Infrared spectroscopy and thermal analysis showed that hydrogen bonds were formed between the inclusion complexes and PCL/FD nanofibrous membranes, which improved the thermal stability of the fibrous membrane. The membrane exhibited the sustained release characteristics of EGC within 240 h and exhibited excellent antibacterial properties in vitro and in vivo. These results indicated that the developed nanofibrous membranes have promising applications in food packaging.

Statistically developed stable Camptothecin-loaded Soluplus/TPGS mixed micelles for improved ovarian cancer treatment

In this research, Camptothecin-loaded mixed micelles (CPT-MMs) were formulated by combining Soluplus®, a novel amphiphilic excipient, with D-alpha-tocopheryl polyethylene glycol 1000 succinate (TPGS). The use of appropriate excipients is crucial in stabilizing micellar structures and improving drug entrapment efficiency. TPGS, with its ability to self-assemble into micelles, was an ideal candidate, and incorporating Soluplus further enhanced micelle stability and drug-loading capacity. A 32 full factorial design was employed to investigate the influence of key factors on particle size and %entrapment efficiency (%EE). The statistical analysis using Design Expert® VR software provided meaningful conclusions on the significance of each factor and their interactions, facilitating the successful optimization of CPT-MMs dispersion with improved drug delivery capabilities. The mean particle size, zeta potential, %drug loading capacity (%DLC), and (%EE) of CPT-MMs were 77.8 ± 2.67 nm, −23.4 ± 0.36 mV, 45.6 ± 1.78%, and 68.61 ± 1.8% respectively. CPT-MMs demonstrated sustained-release characteristics, preventing premature drug release and enhancing drug accumulation in tumor tissues, potentially optimizing CPT delivery for cancer treatment. Importantly, CPT-MMs dispersion exhibited lower hemolysis compared to plain CPT, indicating excellent biocompatibility and safety for intravenous administration. The sustained release of CPT from CPT-MMs dispersion may lead to reduced cytotoxicity and improved therapeutic efficacy. Additionally, the lyophilized formulation showed superior stability compared to the liquid micelles. In conclusion, the development of CPT-MMs presents a promising strategy for enhancing drug delivery and optimizing therapeutic outcomes in cancer treatment. The sustained-release feature, along with enhanced biocompatibility and stability, holds great potential for the clinical translation of these MMs as efficient drug delivery systems for ovarian cancer treatment.

Chitosan film of thiolated TPGS-modified Au-Ag nanoparticles for combating multidrug-resistant bacteria

The widely used vitamin-E based amphiphilic material, tocopheryl polyethylene glycol succinate (TPGS) was further improvised to redox-sensitive thiolated TPGS (TPGS-SH), which has been achieved by attaching 4-aminothiophenol. Further, TPGS and TPGS-SH-coated bimetallic gold-silver nanoparticles (TPGS-Au-Ag-NP and TPGS-SH-Au-Ag-NP) were formulated to explore their antibacterial and wound healing abilities. The prepared NP were monodisperse with a mean hydrodynamic diameter of 69.5±3.23 nm, 59.65±3.23 nm, PDI of 0.3±0.05, 0.2±0.03 and a zeta potential of +29.2±2.71 mV and +35.28±1.53 mV, respectively. The TPGS and TPGS-SH modified Au-Ag-NP were tested for their antibacterial efficacy against methicillin-resistant Staphylococcus aureus (MRSA) and E. coli; minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) results showed that TPGS Au-Ag-NP, TPGS-SH-Au-Ag-NP displayed significantly stronger antibacterial activity than their coating material alone. The anti-efflux pump activity of the most potent antibacterial agent TPGS-SH-Au-Ag-NP was evaluated against MRSA. Toxicity assessment of TPGS-SH-Au-Ag-NP in human dermal fibroblasts showed 88% viability up to 125 µg/mL. The TPGS-SH-Au-Ag-NP, after incorporation in chitosan film (TPGS-SH-Au-Ag-NP-CS), exhibited sustained release and prolonged in vivo residence characteristics, which were evaluated by IVIS. Results also revealed that treatment with TPGS-SH-Au-Ag-NP showed a significant 87% wound healing rate after 12 days of application in the rat model. Hence, we concluded that TPGS-SH-Au-Ag-NP was safe and effective against test bacteria MRSA and capable of efficient wound healing when incorporated in chitosan film.

Development of an Accelerated Rotator-based Drug Release Method for the Evaluation of Bupivacaine Multivesicular Liposomes.

A multivesicular liposome (MVL) is a liposomal vehicle designed to achieve sustained release characteristics for drugs with short half-lives. For example, a commercial MVL formulation of bupivacaine has been approved by the U.S. Food and Drug Administration for local and regional analgesia. For complex formulations like those containing MVLs, challenges in developing an in vitro release testing (IVRT) method may hinder generic development and regulatory approval. In this study, we developed an accelerated rotator-based IVRT method with the ability to discriminate bupivacaine MVLs with different quality attributes. Three IVRT experimental setups including mesh tube, horizontal shaker, and vertical rotator were screened to ensure that at least 50% of bupivacaine can release from MVLs in 24h. Sample dilution factors, incubation temperature, and the release media pH were optimized for the IVRT. The reproducibility of the developed IVRT method was validated with commercial bupivacaine MVLs. The discriminative capacity was assessed via comparing commercial and compromised bupivacaine MVL formulations. The rotator-based release setup was chosen due to the capability to obtain 70% of drug release within 24h. The optimized testing conditions were chosen with a 50-fold dilution factor, a temperature of 37ºC, and a media pH of 7.4. An accelerated rotator-based IVRT method for bupivacaine MVLs was developed in this study, with the discriminatory ability to distinguish between formulations of different qualities. The developed IVRT method was a robust tool for generic development of MVL based formulations.

Temporal control in shell-core structured nanofilm for tracheal cartilage regeneration: synergistic optimization of anti-inflammation and chondrogenesis.

Cartilage tissue engineering offers hope for tracheal cartilage defect repair. Establishing an anti-inflammatory microenvironment stands as a prerequisite for successful tracheal cartilage restoration, especially in immunocompetent animals. Hence, scaffolds inducing an anti-inflammatory response before chondrogenesis are crucial for effectively addressing tracheal cartilage defects. Herein, we develop a shell-core structured PLGA@ICA-GT@KGN nanofilm using poly(lactic-co-glycolic acid) (PLGA) and icariin (ICA, an anti-inflammatory drug) as the shell layer and gelatin (GT) and kartogenin (KGN, a chondrogenic factor) as the core via coaxial electrospinning technology. The resultant PLGA@ICA-GT@KGN nanofilm exhibited a characteristic fibrous structure and demonstrated high biocompatibility. Notably, it showcased sustained release characteristics, releasing ICA within the initial 0 to 15 days and gradually releasing KGN between 11 and 29 days. Subsequent in vitro analysis revealed the potent anti-inflammatory capabilities of the released ICA from the shell layer, while the KGN released from the core layer effectively induced chondrogenic differentiation of bone marrow stem cells (BMSCs). Following this, the synthesized PLGA@ICA-GT@KGN nanofilms were loaded with BMSCs and stacked layer by layer, adhering to a 'sandwich model' to form a composite sandwich construct. This construct was then utilized to repair circular tracheal defects in a rabbit model. The sequential release of ICA and KGN facilitated by the PLGA@ICA-GT@KGN nanofilm established an anti-inflammatory microenvironment before initiating chondrogenic induction, leading to effective tracheal cartilage restoration. This study underscores the significance of shell-core structured nanofilms in temporally regulating anti-inflammation and chondrogenesis. This approach offers a novel perspective for addressing tracheal cartilage defects, potentially revolutionizing their treatment methodologies.

Quercetin-loaded PLGA nanoparticles coating with macrophage membranes for targeted delivery in acute liver injury

Quercetin (QU), a natural flavonoid with potent anti-inflammatory and antioxidant properties, holds promise in treating acute liver injury (ALI). Nonetheless, its limited solubility hampers its efficacy, and its systemic distribution lacks targeting, leading to off-target effects. To address these challenges, we developed macrophage membrane-coated quercetin-loaded PLGA nanoparticles (MVs-QU-NPs) for active ALI targeting. The resulting MVs-QU-NPs exhibited a spherical morphology with a clear core–shell structure. The average size and zeta potential were assessed as 141.70 ± 0.89 nm and –31.83 ± 0.76 mV, respectively. Further studies revealed sustained drug release characteristics from MVs-QU-NPs over a continuous period of 24 h. Moreover, these MVs-QU-NPs demonstrated excellent biocompatibility when tested on normal liver cells. The results of biodistribution analysis in ALI mice displayed the remarkable ALI-targeting ability of MVs-DiD-NPs, with the highest fluorescence intensity observed in liver tissue. This biomimetic approach combining macrophage membranes with nanoparticle delivery, holds great potential for targeted ALI treatment.

Preparation and evaluation of floating drug delivery system (fdds) containing an antiviral drug

Acyclovir, an antiviral drug has low oral bioavailability of about 15-30%. It shows more absorption in the upper gastro intestinal tract. The main objective is to evaluate the potential of floating alginate beads as a drug carrier for acyclovir to prolong gastric residence time of drug in its absorption window. Floating beads were prepared from sodium alginate solution containing CaCO3 as gas-forming agent using Ionotropic gelation method. To overcome the limitation of drug leaching during preparation and to have improved sustained release characteristics, alginate beads were prepared with the addition of polymers like Hydroxy propyl methyl cellulose (HPMC K4M), Eudragit RL 100 and Xanthan gum. Beads were also prepared by using Pectin (polyelectrolyte) containing cross linking solution. The compatibility of drug with the polymer was confirmed through the FT-IR studies. The prepared beads were evaluated for percentage drug loading, entrapment efficiency, surface morphology and in vitro release characteristics to know the effect of addition of these polymers to alginate solution and the addition of Pectin to cross linking solution. Pectin treated beads prepared with Xanthan gum &amp; Pectin not only showed improved percentage drug loading but also exhibited sustained drug release in the pH 1.2. So these floating alginate beads may act as a promising carrier for acyclovir to improve its oral bioavailability.

Preparation and characterization of hexaconazole/hydroxypropyl-gamma-cyclodextrin inclusion complex nanofibers for sustainable agriculture: Improved physicochemical properties and antifungal activity of hexaconazole

Hexaconazole (HEZ) is a triazole fungicide with low water solubility, which restricts its use in agricultural production. In this work, HEZ/hydroxypropyl-γ-cyclodextrin inclusion complex nanofibers (HEZ/HPγCD-IC-NF) were successfully prepared to improve the antifungal activity of HEZ. Physicochemical properties and antifungal activity of HEZ/HPγCD-IC-NF were characterized and evaluated by several key technologies. The results confirmed that HEZ was completely encapsulated in the hydroxypropyl-γ-cyclodextrin cavity, and the thermal stability and water solubility of HEZ could be enhanced by preparing HEZ/HPγCD-IC-NF. Importantly, the antifungal activity of HEZ against Botrytis cinerea was significantly enhanced by the preparation of HEZ/HPγCD-IC-NF (1.92 times to that of HEZ). Furthermore, HEZ/HPγCD-IC-NF also showed sustained release characteristics. This research attempts to develop a new formulation based on insoluble fungicides to reduce the dosage of fungicides and promote the development of green agriculture.

Regulation Mechanism of Phenolic Hydroxyl Number on Self-Assembly and Interaction between Edible Dock Protein and Hydrophobic Flavonoids.

In this study, galangin (Gal), kaempferol (Kae), quercetin (Que), and myricetin (Myr) were chosen as the representative flavonoids with different phenolic hydroxyl numbers in the B-ring. The edible dock protein (EDP) was chosen as the new plant protein. Based on this, the regulation mechanism of the phenolic hydroxyl number on the self-assembly behavior and molecular interaction between EDP and flavonoid components were investigated. Results indicated that the loading capacity order of flavonoids within the EDP nanomicelles was Myr (10.92%) > Que (9.56%) > Kae (6.63%) > Gal (5.55%). Moreover, this order was consistent with the order of the hydroxyl number in the flavonoid's B ring: Myr (3) > Que (2) > Kae (1) > Gal (0). The micro morphology exhibited that four flavonoid-EDP nanomicelles had a core-shell structure. In the meantime, the EDP encapsulation remarkably improved the flavonoids' water solubility, storage stability, and sustained release characteristics. During the interaction of EDP and flavonoids, the noncovalent interactions including van der Waals forces, hydrophobic interaction, and hydrogen bonding were the main binding forces. All of the results demonstrated that the hydroxyl number of bioactive compounds is a critical factor for developing a delivery system with high loading ability and stability.