Synthesis and Evaluation of Rutin–Hydroxypropyl β-Cyclodextrin Inclusion Complexes Embedded in Xanthan Gum-Based (HPMC-g-AMPS) Hydrogels for Oral Controlled Drug Delivery

Functionalization of almond gum through covalent and non-covalent interactions for biomedical applications

The versatile properties of carbohydrate polymers make them a relevant, promising precursor to design innovative materials for use in biomedical applications. Recent research mainly focuses on the development of the polysaccharide based functional materials. Hydrogel derived materials are a source of great motivation for the development of drug delivery (DD) carriers with inherent therapeutic potential. Herein, almond gum-based hydrogels were synthesized for the delivery of the anticancer drug methotrexate after impregnation to improve the DD profile. Hydrogels were characterized by FESEM, EDS, AFM, 13C NMR, FTIR, TGA, DSC, XRD, mechanical strength & biomedical assay. The optimized network hydrogel exhibited a mesh size of 19.764 mm and a cross-linking density of 5.002 × 10-5 mol/cm3 of the hydrogels. Morphological features revealed irregular, uneven internal morphology of hydrogels in FE-SEM. The inclusion of sulphated and amide polymers in hydrogels was found in elemental composition (C = 60.72 %, O = 29.79 %, N = 6.63 % and S = 2.86 %) of hydrogels inferred from EDS. Spectroscopic characterization by FT-IR and 13C NMR confirmed the inclusion of PVP and PVSA through grafting reaction. The crosslinked product formed was found thermally stable and amorphous in nature through TGA and XRD analysis. The sustained release was found through supramolecular interactions and release complied a non-Fickian mechanism for drug diffusion (n = 0.73) and the release profile was best described by the Hixson-Crowell kinetic model in colonic pH. The hydrogels were mucoadhesive in nature and required 144 ± 10.54 mN force for the separation of hydrogels from the mucosal surface during the adhesion test. Hydrogel illustrated antioxidant activity (32.68 ± 0.83 μg GAE) during their radical scavenging test by FC reagent assay. Drug encapsulated hydrogels demonstrated antimicrobial efficacy against microbes. The results of physico-chemical and biomedical properties of hydrogels suggested their suitability for biomedical uses.

Cyclodextrin-Hydrogel Hybrids in Advanced Drug Delivery

Cyclodextrin (CD)-hydrogel hybrids have emerged as versatile and multifunctional drug delivery systems, offering enhanced solubility, controlled drug release, and improved bioavailability. By combining the inclusion complexation properties of CDs with the swelling and retention capabilities of hydrogels, these hybrid systems overcome key challenges in conventional drug formulations. This review explores CD composition, hydrogel polymer selection, fabrication techniques, key drug release factors, and real-world therapeutic applications. Additionally, the latest advancements in stimuli-responsive hydrogels, nanogels, and microneedle-based drug delivery are discussed. While CD-hydrogel systems demonstrate significant potential, scalability, regulatory hurdles, and clinical translation remain key challenges. Future research should focus on smart hydrogels, improved drug loading strategies, and enhanced clinical validation to bridge the gap between laboratory innovations and commercial applications.

Approaches for Inclusion Complexes of Ezetimibe with Cyclodextrins: Strategies for Solubility Enhancement and Interaction Analysis via Molecular Docking

This study aimed to improve the solubility of ezetimibe (EZT), which has low aqueous solubility, by preparing complexes using β-cyclodextrin (β-CD) derivatives. Phase solubility studies and Job's plot confirmed a high apparent stability constant for EZT with β-CD and even higher constants with its derivatives, establishing a 1:1 stoichiometric ratio. The composites were prepared using spray drying over a range of molar ratios, and their physicochemical properties were evaluated using techniques such as scanning electron microscopy (SEM), powder X-ray diffraction (PXRD), and Fourier transform infrared spectroscopy (FT-IR). Saturation solubility and in vitro dissolution tests revealed that solubility increased with higher CD molar ratios. EZT/RM-β-CD inclusion complexes (ICs) and EZT/DM-β-CD ICs exhibited a similar solubility, which was greater than that of EZT/HP-β-CD ICs and EZT/SBE-β-CD ICs (where RM, DM, HP, and SEB represent H, CH3, -CH2-CHOH-CH3 and -(CH2)4-SO3Na synthetic derivatives, respectively). Most complexes, except for EZT/SBE-β-CD at 1:2 or higher ratios, showed superior solubility compared with EZT powder and commercial products. Molecular docking simulations confirmed EZT inclusion within the CD, revealing hydrogen bonds and binding energies that aligned with solubility trends. These findings suggest that EZT complexes with β-CD derivatives significantly improve solubility, highlighting their potential for developing more effective oral solid formulations for hyperlipidemia treatment.

Potential Use of Selected Natural Compounds with Anti-Biofilm Activity

Antibiotic resistance in microorganisms is an escalating global concern, exacerbated by their formation of biofilms, which provide protection through an extracellular matrix and communication via quorum sensing, enhancing their resistance to treatment. This situation has driven the search for alternative approaches, particularly those using natural compounds. This study explores the potential of phytochemicals, such as quercetin, apigenin, arbutin, gallic acid, proanthocyanidins, and rutin, known for their antibacterial properties and ability to inhibit biofilm formation and disrupt mature biofilms. The methods used in this study included a comprehensive review of current literature assessing the bioavailability, distribution, and effective concentrations of these compounds in treating biofilm-associated infections. The results indicate that these phytochemicals exhibit significant antibacterial effects, reduce biofilm's structural integrity, and inhibit bacterial communication pathways. Moreover, their potential use in combination with existing antibiotics may enhance therapeutic outcomes. The findings support the conclusion that phytochemicals offer promising additions to anti-biofilm strategies and are capable of complementing or replacing conventional treatments, with appropriate therapeutic levels and delivery mechanisms being key to their effectiveness. This insight underscores the need for further research into their clinical applications for treating infections complicated by biofilms.

Selection strategy for encapsulation of hydrophilic and hydrophobic ingredients with food-grade materials: A systematic review and analysis

Various lipid and biopolymer-based nanocarriers have been developed to encapsulate food ingredients. The selection of nanocarrier type, preparation techniques, and loading methods should consider the compatibility of nutrient properties, nanocarrier composition, and product requirements. This review focuses on the loading methods for hydrophilic and hydrophobic substances, along with a detailed exploration of nanocarrier categorization, composition, and preparation methods. Both lipid-based and biopolymer-based nanoparticles exhibit the capability to encapsulate hydrophilic or hydrophobic substances. Liposomes and nanoemulsions allow simultaneous encapsulation of hydrophilic and hydrophobic ingredients, while solid lipid nanoparticles and nanostructured lipid carriers are suited for hydrophobic ingredients. The three-dimensional network structure of nanogels can efficiently load hydrophilic substances, while the functional groups in polysaccharides improve the loading capacity of hydrophobic substances through intermolecular interactions. As for protein nanoparticles, the selection of proteins with solubility characteristics analogous to the bioactives is crucial to achieve high encapsulation efficiency.

Synthetic and natural polymer hydrogels: A review of 3D spheroids and drug delivery

This review centers on the synthesis and characterization of both natural and synthetic hydrogels, highlighting their diverse applications across various fields. We will delve into the evolution of hydrogels, focusing on the importance of polysaccharide-based and synthetic variants, which have been particularly chosen for 3D spheroid development in cancer research and drug delivery. A detailed background on the research and specific methodologies, including the in-situ free radical polymerization used for synthesizing these hydrogels, will be extensively discussed. Additionally, the review will explore various applications of these hydrogels, such as their self-healing properties, swelling ratios, pH responsiveness, and cell viability. A comprehensive literature review will support this investigation. Ultimately, this review aims to clearly outline the objectives and significance of hydrogel synthesis and their applications.

Rutin loaded bilosomes for enhancing the oral activity and nephroprotective effects of rutin in potassium dichromate induced acute nephrotoxicity in rats

Rutin, a flavone glycoside, has shown to have a significant beneficial kidney protection effect in drug-induced nephropathy. However, its poor solubility and low oral bioavailability have limited its pharmacological applications. This study aimed at formulating rutin-loaded bilosomes to enhance the renal protective effect of rutin for oral application. Rutin-loaded bilosomes were developed using thin-film hydration technique. The prepared formulations were characterized by entrapment efficiency percentage (EE%), vesicular size (VS) and zeta potential (ZP) measurement. The developed formula exhibited moderate EE%, ranging from 20.02 ± 2.85 to 48.57 ± 3.57%, suitable VS results that ranged from 502.1 ± 36 to 665.1 ± 45 nm and high ZP values (≤ -41.4 ± 7.27 mV). Transmission electron microscopy revealed the spherical shape of the developed bilosomes. The in-vitro release study revealed prolonged release of rutin from bilosomes, relative to free drug. F2, prepared using the molar ratio span 60: cholesterol: sodium cholate 1:1:0.5, was selected for further investigations as it showed the highest EE%, smallest VS, optimum ZP, and persistent release profile. In-vivo studies were performed on drug-induced nephropathy in rats. Acute renal failure was induced using a single dose of potassium dichromate (PDC; 15 mg/kg; i.p). The selected formulation, F2, alleviated kidney dysfunction, oxidative stress and inflammation via decreasing MDA, TNF-α and TGF-β and increasing GSH. In addition, F2 promoted Akt/PI3K activation against PDC-induced acute renal failure. Histopathology results came in accordance with in-vivo results. Thus, bilosomes could be considered a potential delivery system for enhancing the oral delivery and kidney protection activity of rutin.

Enteral Route Nanomedicine for Cancer Therapy

With the in-depth knowledge of the pathological and physiological characteristics of the intestinal barrier-portal vein/intestinal lymphatic vessels-systemic circulation axis, oral targeted drug delivery is frequently being renewed. With many advantages, such as high safety, convenient administration, and good patient compliance, many researchers have begun to explore targeted drug delivery from intravenous injections to oral administration. Over the past few decades, the fields of materials science and nanomedicine have produced various drug delivery platforms that hold great potential in overcoming the multiple barriers associated with oral drug delivery. However, the oral transport of particles into the systemic circulation is extremely difficult due to immune rejection and biochemical invasion in the intestine, which limits absorption and entry into the bloodstream. The feasibility of the oral delivery of targeted drugs to sites outside the gastrointestinal tract (GIT) is unknown. This article reviews the biological barriers to drug absorption, the in vivo fate and transport mechanisms of drug carriers, the theoretical basis for oral administration, and the impact of carrier structural evolution on oral administration to achieve this goal. Finally, this article reviews the characteristics of different nano-delivery systems that can enhance the bioavailability of oral therapeutics and highlights their applications in the efficient creation of oral anticancer nanomedicines.

Cyclodextrin in drug delivery: Exploring scaffolds, properties, and cutting-edge applications

Cyclodextrins (CDs) are unique cyclic compounds that can form inclusion complexes via host-guest complexation with a wide range of molecules, thereby altering their physicochemical properties. These molecules offer the formation of inclusion complexes without the formation of covalent bonds, making them suitable for a variety of applications in pharmaceutical and biomedical fields. Due to their supramolecular host-guest properties, CDs are being utilized in the fabrication of biomaterials, metal-organic frameworks, and nano-drug carriers. Additionally, CDs in combination with biomolecules are biocompatible and can deliver nano to macromolecules at the site of drug actions. However, the availability of free hydroxyl groups and a simple crosslinking process for supramolecular fabrication show immense opportunities for researchers in the field of tissue engineering and biomedical applications. In this review article, we have covered the historical development, various types of chemical frameworks, unique chemical and physical properties, and important applications of CDs in drug delivery and biomedical sciences.

Design and Evaluation of Inorganic/Organic Hybrid Bio-composite for Site-Specific Oral Delivery of Darifenacin

Benign hyperplasia (BHP) is a common disorder that affects men over the age of 60 years. Transurethral resection of the prostate (TURP) is the gold standard for operative treatment, but a range of drugs are also available to improve quality of life and to reduce BHP-associated urinary tract infections and complications. Darifenacin, an anti-muscarinic agent, has been found effective for relieving symptoms of overactive bladder associated with BHP, but the drug has poor solubility and bioavailability, which are major challenges in product development. An inorganic/organic bio-composite with gastric pH-resistant property was synthesized for the targeted oral delivery of Darifenacin to the lower gastrointestinal tract (GIT). This development was accomplished through co-precipitation of calcium carbonate in quince seed-based mucilage. The FTIR, XRD, DSC, and TGA results showed good drug-polymer compatibility, and the SEM images showed calcite formation in the quince hydrogel system. After 72 h, the drug release of 34% and 75% were observed in acidic (0.1N HCl) and 6.8 pH phosphate buffer, respectively. A restricted/less drug was permeated through gastric membrane (21.8%) as compared to permeation through intestinal membrane (65%.) The developed composite showed significant reduction in testosterone-induced prostatic hyperplasia (2.39 ± 0.12***) as compared to untreated diseased animal group. No sign of organ toxicity was observed against all the developed composites. In this study, we developed an inorganic-organic composite system that is highly biocompatible and effective for targeting the lower GIT, thereby avoiding the first-pass metabolism of darifenacin.

Preparation, solubility, and anti-inflammatory effects of a complex of diphenylcyclopropenone/β-cyclodextrin derivatives as the treatment of alopecia areata

Purpose

To investigate the preparation of inclusion complexes of diphenylcyclopropenone (DPCP)/β-cyclodextrin (β-CD) derivatives using a three-dimensional (3D) ball mill, and verify the inclusion behavior of the solid dispersion. Additionally, we aimed to investigate the effect of DPCP/β-CDs complex formation on the spleens of male C57BL/6 mice in terms of anti-inflammatory effects.

Methods

The inclusion complexes of DPCP with β-CD and hydroxypropyl-β-cyclodextrin (HPβCD) were prepared using a 3D ball mill. Powder X-ray diffraction (PXRD) and Fourier-transform infrared spectroscopy (FT-IR) were used to evaluate the solid-state properties. The solubility of the prepared DPCP/β-CD and HPβCD complexes and the intermolecular interaction between DPCP and β-CD derivatives in solution were assessed using 1H nuclear magnetic resonance (NMR). Furthermore, the anti-inflammatory effects of DPCPs in the prepared DPCP/CD complexes were investigated using spleens from male C57BL/6 mice, with measurement of interferon gamma (IFN-γ) secretion as an endpoint. Additionally, the protective effects of each drug on NIH-3T3 cells exposed to ultraviolet (UV) irradiation were examined.

Results

Solid-state characterization confirmed the formation of inclusion complexes in the 3D ground mixture (3DGM) (DPCP/β-CD = 1/1) and 3DGM (DPCP/HPβCD = 1/1) complexes through PXRD and IR analysis. The solubility of 3DGM (DPCP/β-CD = 1/1) and 3DGM (DPCP/HPβCD = 1/1) was 17.5 μg/mL and 58.4 μg/mL, respectively, indicating higher solubility than that of DPCP alone. NMR analysis of 3DGM samples suggested that DPCP/β-CD and DPCP/HPβCD form inclusion complexes at a molar ratio of 1/1 but with different inclusion modes. Regarding the anti-inflammatory activity of DPCP, 3DGM (DPCP/HPβ-CD) showed anti-inflammatory effects at lower doses compared to 3DGM (DPCP/β-CD) in terms of IFN-γ and NIH-3T3 cells injured by UV irradiation.

Conclusion

We successfully formed inclusion complexes of DPCP/β-CD and DPCP/HPβCD using the 3D ground mixture method. NMR analysis suggested that DPCP/β-CD and DPCP/HPβCD form inclusion complexes at a molar ratio of 1/1 but with different inclusion modes. The anti-inflammatory activity of DPCP was more pronounced in 3DGM (DPCP/HPβCD) at lower doses compared to that in 3DGM (DPCP/β-CD), indicating that the HPβCD derivatives were more effective in enhancing the anti-inflammatory properties of DPCP.

Application of hydrogels in cancer immunotherapy: a bibliometric analysis

Background

Cancer immunotherapy has made significant progress in recent years, with numerous studies worldwide. Immunotherapy has had a transformative impact on oncology and autoimmune diseases. In the biomedical arena, hydrogels with good properties are widely used in cancer immunotherapy. Our study used bibliometrics to analyze the changing trends in using hydrogels for cancer immunotherapy.

Methods

From 2013 to 2023, a systematic search was conducted in the Web of Science Core Collection database to identify reviews and articles discussing the applications of hydrogels in cancer immunotherapy. The software CiteSpace was used to visually perform the bibliometric analysis in terms of research trends, countries, institutions, authors, journals, and keywords. Individual authors' productivity was assessed with the Lotka's law. The most relevant publication sources were identified by Bradford's law.

Results

A total of 422 English-language publications related to hydrogels in cancer immunotherapy were collected. The number of annual publications increased rapidly after 2021 and remained constant for the past two years. China published the most articles in this field. The institution with the maximum number of published articles was the Chinese Academy of Sciences in China. Chen. Q was the most prolific author, and Liu. Z was the second most published author. In terms of journal contributions, the journal "Biomaterials" had the highest number of publications (n = 30). Biomaterials, Advanced Functional Materials and Journal of Controlled Release were the most influential journals. Keyword analysis revealed that cancer immunotherapy, drug delivery, immunogenic cell death, tumor microenvironment, injectable hydrogels, and immune checkpoint blockade were the primary research hotspots. In recent 3 years, adoptive T-cell therapy, black phosphorus, cell capture, adaptive cell therapy, tumor microenvironment, photodynamic therapy, and sustained release were the research hotspots in this field. Our study summarizes the objective of hydrogels in cancer immunotherapy in recent years, providing a reference for potential researchers in related field.

Conclusion

This bibliometric analysis shows the progress and trend of research on hydrogels in cancer immunotherapy. This study provides a significant avenue for future investigation into current concerns and trends in research within this field.

Highly swellable, cytocompatible and biodegradeable guar gum-based hydrogel system for controlled release of bioactive components of liquorice (Glycyrrhiza glabra L.): Synthesis and evaluation

Glycyrrhiza glabra Linn (liquorice) has been widely used for therapeutic purposes to treat digestive disorders, immunomodulatory disorders, inflammatory disorders, diabetes, viral infections, and cancer. Liquorice contains a wide variety of bioactive compounds, including glycyrrhizin, flavonoids, and terpenoids. Several factors compromise their therapeutic efficacy, such as poor pharmacokinetic profiles and physicochemical properties. Therefore, to improve its overall effectiveness, liquorice solid dispersion (LSD) was incorporated into biopolymer-based guar gum-grafted-2-acrylamido-2-methylpropane sulfonic acid (Guar gum-g-AMPS) hydrogels designed for controlled delivery via the oral route and characterized. The qualitative analysis of LSD revealed 51 compounds. Hydrogel structural properties were assessed for their effect on swelling and release. The highest swelling ratio (6413 %) and drug release (84.12 %) occurred at pH 1.2 compared to pH 7.4 (swelling ratio of 2721 % and drug release of 79.36 %) in 48 h. The hydrogels exhibited high porosity (84.23 %) and biodegradation (9.30 % in 7 days). In vitro hemolysis tests have demonstrated the compatibility of the hydrogel with blood. CCK-8 assay confirmed the biocompatibility of the synthesized hydrogel using osteoblasts and RIN-m5f cells. LSD exhibited good anti-inflammatory activity when loaded into hydrogels after being subjected to protein denaturation experiments. Moreover, LSD-loaded hydrogels have good antioxidant and antibacterial properties.

ULK1 Mediated Autophagy-Promoting Effects of Rutin-Loaded Chitosan Nanoparticles Contribute to the Activation of NF-κB Signaling Besides Inhibiting EMT in Hep3B Hepatoma Cells

Background

Liver cancer remains to be one of the leading causes of cancer worldwide. The treatment options face several challenges and nanomaterials have proven to improve the bioavailability of several drug candidates and their applications in nanomedicine. Specifically, chitosan nanoparticles (CNPs) are extremely biodegradable, pose enhanced biocompatibility and are considered safe for use in medicine.

Methods

CNPs were synthesized by ionic gelation, loaded with rutin (rCNPs) and characterized by ultraviolet-visible spectroscopy (UV-Vis), Fourier-transform infrared spectroscopy (FTIR), dynamic light scattering (DLS) and transmission electron microscopy (TEM). The rCNPs were tested for their cytotoxic effects on human hepatoma Hep3B cells, and experiments were conducted to determine the mechanism of such effects. Further, the biocompatibility of the rCNPs was tested on L929 fibroblasts, and their hemocompatibility was determined.

Results

Initially, UV-vis and FTIR analyses indicated the possible loading of rutin on rCNPs. Further, the rutin load was quantitatively measured using Ultra-Performance Liquid Chromatography (UPLC) and the concentration was 88 µg/mL for 0.22 micron filtered rCNPs. The drug loading capacity (LC%) of the rCNPs was observed to be 13.29 ± 0.68%, and encapsulation efficiency (EE%) was 19.55 ± 1.01%. The drug release was pH-responsive as 88.58% of the drug was released after 24 hrs at the lysosomal pH 5.5, whereas 91.44% of the drug was released at physiological pH 7.4 after 102 hrs. The cytotoxic effects were prominent in 0.22 micron filtered samples of 5 mg/mL rutin precursor. The particle size for the rCNPs at this concentration was 144.1 nm and the polydispersity index (PDI) was 0.244, which is deemed to be ideal for tumor targeting. A zeta potential (ζ-potential) value of 16.4 mV indicated rCNPs with good stability. The IC50 value for the cytotoxic effects of rCNPs on human hepatoma Hep3B cells was 9.7 ± 0.19 μg/mL of rutin load. In addition, the increased production of reactive oxygen species (ROS) and changes in mitochondrial membrane potential (MMP) were observed. Gene expression studies indicated that the mechanism for cytotoxic effects of rCNPs on Hep3B cells was due to the activation of Unc-51-like autophagy-activating kinase (ULK1) mediated autophagy and nuclear factor kappa B (NF-κB) signaling besides inhibiting the epithelial-mesenchymal Transition (EMT). In addition, the rCNPs were less toxic on NCTC clone 929 (L929) fibroblasts in comparison to the Hep3B cells and possessed excellent hemocompatibility (less than 2% of hemolysis).

Conclusion

The synthesized rCNPs were pH-responsive and possessed the physicochemical properties suitable for tumor targeting. The particles were effectively cytotoxic on Hep3B cells in comparison to normal cells and possessed excellent hemocompatibility. The very low hemolytic profile of rCNPs indicates that the drug could be administered intravenously for cancer therapy.

Crosslinked PVA-g-poly(AMPS) Nanogels for Enhanced Solubility and Dissolution of Ticagrelor: Synthesis, Characterization, and Toxicity Evaluation

In this study, we synthesized PVA-g-poly(AMPS) nanogels with the aim of enhancing the solubility and dissolution of ticagrelor (TGR). Ticagrelor, a noncompetitive, reversible P2Y12 receptor antagonist, is prescribed to treat acute coronary syndrome. Ticagrelor has restricted oral bioavailability (≈36%) because of its poor solubility and permeability. The free radical polymerization methodology was employed to synthesize nanogels with varied concentrations of poly(vinyl alcohol) (polymer), 2-acrylamido-2-methylpropanesulfonic acid (monomer), and N,N-methylene bis(acrylamide) (crosslinker). The prepared nanogels were analyzed by swelling studies, % drug entrapment efficiency (DEE), solubility studies, in vitro drug release studies, zeta sizer, Fourier transform infrared (FTIR) spectroscopy, powder X-ray diffraction (PXRD), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), and scanning electron microscopy (SEM). The optimized formulation (PA5) revealed a particle size of 45.86 nm, with a polydispersity index (PDI) of 0.41 and a %DEE of 85.1%. FTIR spectroscopy, XRD, and SEM confirmed the formation of crosslinked nanogels with amorphous and porous structures, and TGA/DSC proved their thermal stability. In vitro dissolution studies showed 99.91% drug release, and the ticagrelor solubility from the synthesized formulations was significantly improved up to 8.2-fold. All formulations followed the Korsmeyer-Peppas model with the Fickian diffusion as the release mechanism. The toxicity studies carried out on rats and the MTT assay on the Caco-2 cell line validated the biocompatibility of the nanogel formulations. The outcomes of the current study led to the conclusion that the PVA-g-poly(AMPS) nanogels synthesized by us could be used as dedicated pharmaceutical delivery systems to achieve enhanced solubility and dissolution of ticagrelor.

The development of nanocarriers for natural products

Natural bioactive compounds from plants exhibit substantial pharmacological potency and therapeutic value. However, the development of most plant bioactive compounds is hindered by low solubility and instability. Conventional pharmaceutical forms, such as tablets and capsules, only partially overcome these limitations, restricting their efficacy. With the recent development of nanotechnology, nanocarriers can enhance the bioavailability, stability, and precise intracellular transport of plant bioactive compounds. Researchers are increasingly integrating nanocarrier-based drug delivery systems (NDDS) into the development of natural plant compounds with significant success. Moreover, natural products benefit from nanotechnological enhancement and contribute to the innovation and optimization of nanocarriers via self-assembly, grafting modifications, and biomimetic designs. This review aims to elucidate the collaborative and reciprocal advancement achieved by integrating nanocarriers with botanical products, such as bioactive compounds, polysaccharides, proteins, and extracellular vesicles. This review underscores the salient challenges in nanomedicine, encompassing long-term safety evaluations of nanomedicine formulations, precise targeting mechanisms, biodistribution complexities, and hurdles in clinical translation. Further, this study provides new perspectives to leverage nanotechnology in promoting the development and optimization of natural plant products for nanomedical applications and guiding the progression of NDDS toward enhanced efficiency, precision, and safety. This article is categorized under: Therapeutic Approaches and Drug Discovery > Emerging Technologies Nanotechnology Approaches to Biology > Nanoscale Systems in Biology.

Enhanced Cellular Delivery of Tildipirosin by Xanthan Gum-Gelatin Composite Nanogels

Tildipirosin has no significant inhibitory effect on intracellular bacteria because of its poor membrane permeability. To this end, tildipirosin-loaded xanthan gum-gelatin composite nanogels were innovatively prepared to improve the cellular uptake efficiency. The formation of the nanogels via interactions between the positively charged gelatin and the negatively charged xanthan gum was confirmed by powder X-ray diffraction and Fourier transform infrared. The results indicate that the optimal tildipirosin composite nanogels possessed a 3D network structure and were shaped like a uniformly dispersed ellipse, and the particle size, PDI, and ζ potential were 229.4 ± 1.5 nm, 0.26 ± 0.04, and -33.2 ± 2.2 mV, respectively. Interestingly, the nanogels exhibited gelatinase-responsive characteristics, robust cellular uptake via clathrin-mediated endocytosis, and excellent sustained release. With those pharmaceutical properties provided by xanthan gum-gelatin composite nanogels, the anti-Staphylococcus aureus activity of tildipirosin was remarkably amplified. Further, tildipirosin composite nanogels demonstrated good biocompatibility and low in vivo and in vitro toxicities. Therefore, we concluded that tildipirosin-loaded xanthan gum-gelatin composite nanogels might be employed as a potentially effective gelatinase-responsive drug delivery for intracellular bacterial infection.

Rutin/Sulfobutylether-β-Cyclodextrin as a Promising Therapeutic Formulation for Ocular Infection

Ocular pathologies present significant challenges to achieving effective therapeutic results due to various anatomical and physiological barriers. Natural products such as flavonoids, alone or in association with allopathic drugs, present many therapeutic actions including anticancer, anti-inflammatory, and antibacterial action. However, their clinical employment is challenging for scientists due to their low water solubility. In this study, we designed a liquid formulation based on rutin/sulfobutylether-β-cyclodextrin (RTN/SBE-β-CD) inclusion complex for treating ocular infections. The correct stoichiometry and the accurate binding constant were determined by employing SupraFit software (2.5.120) in the UV-vis titration experiment. A deep physical-chemical characterization of the RTN/SBE-β-CD inclusion complex was also performed; it confirmed the predominant formation of a stable complex (Kc, 9660 M-1) in a 1:1 molar ratio, with high water solubility that was 20 times (2.5 mg/mL) higher than the free molecule (0.125 mg/mL), permitting the dissolution of the solid complex within 30 min. NMR studies revealed the involvement of the bicyclic flavonoid moiety in the complexation, which was also confirmed by molecular modeling studies. In vitro, the antibacterial and antibiofilm activity of the formulation was assayed against Staphylococcus aureus and Pseudomonas aeruginosa strains. The results demonstrated a significant activity of the formulation than that of the free molecules.

Hydroxyethyl Cellulose-Based Hydrogels as Controlled Release Carriers for Amorphous Solid Dispersion of Bioactive Components of Radix Paeonia Alba

Radix Paeoniae Alba (RPA) has been used extensively in Chinese traditional medicine to treat gastrointestinal disorders, immune-modulating diseases, cancers, and numerous other conditions. A few of its active components include paeoniflorin, albiflorin, lactiflorin, and catechin. However, their therapeutic effectiveness is compromised by poor pharmacokinetic profiles, low oral bioavailability, short half-lives, and poor aqueous solubility. In this study, hydroxyethyl cellulose-grafted-2-acrylamido-2-methylpropane sulfonic acid (HEC-g-AMPS) hydrogels were successfully prepared for the controlled release of Radix Paeonia Alba-solid dispersion (RPA-SD). A total of 43 compounds were identified in RPA-SD using UHPLC-Q-TOF-MS analysis. The hydrogel network formation was confirmed by FTIR, TGA, DSC, XRD, and SEM. Hydrogels' swelling and drug release were slightly higher at pH 1.2 (43.31% swelling, 81.70% drug release) than at pH 7.4 (27.73% swelling, 72.46% drug release) after 48 h. The gel fraction, drug release time and mechanical strength of the hydrogels increased with increased polymer and monomer concentration. Furthermore, the hydrogels were porous (84.15% porosity) and biodegradable (8.9% weight loss per week). Moreover, the synthesized hydrogels exhibited excellent antimicrobial and antioxidative properties.

Drug design strategies that aim to improve the low solubility and poor bioavailability conundrum in quercetin derivatives

INTRODUCTION

Scientists are especially interested in polyphenols, particularly flavonoids. Quercetin, a flavonoid, has demonstrated various therapeutic properties, such as antioxidant, anti-diabetic, anti-hypertensive, and anti-carcinogenic activities. Different plant sources contain varying quantities and types of quercetin. However, quercetin's bioavailability is frequently low due to its low water solubility, molecular stability, and absorption characteristics.

AREAS COVERED

The primary goals of this review are related to the approaches for overcoming quercetin's limitations. Hence, the main tactics for structural modifications (addition of charged and polar groups, removing C2, C3 double bond or reducing aromaticity, disrupting intramolecular H-bond, and reducing crystal lattice stability) and drug delivery systems (cyclodextrin complexes, emulsions, nanoparticles, liposomes, etc.) were discussed to improve water solubility and bioavailability of quercetin.

EXPERT OPINION

From a tactical perspective, enhancing the solubility of compounds can be simplified through decreasing hydrophobic properties or crystalline stability. In addition, an essential field of study focuses on creating appropriate molecular carriers for substances with low water solubility. However, pharmacokinetics, potency, and toxicology are all impacted by the structural factors and physical characteristics that regulate solubility. Poor water solubility is still a major problem in drug discovery, and new methods are always in demand to overcome it.

Polymer-Based Hydrogels Applied in Drug Delivery: An Overview

Polymer-based hydrogels are hydrophilic polymer networks with crosslinks widely applied for drug delivery applications because of their ability to hold large amounts of water and biological fluids and control drug release based on their unique physicochemical properties and biocompatibility. Current trends in the development of hydrogel drug delivery systems involve the release of drugs in response to specific triggers such as pH, temperature, or enzymes for targeted drug delivery and to reduce the potential for systemic toxicity. In addition, developing injectable hydrogel formulations that are easily used and sustain drug release during this extended time is a growing interest. Another emerging trend in hydrogel drug delivery is the synthesis of nano hydrogels and other functional substances for improving targeted drug loading and release efficacy. Following these development trends, advanced hydrogels possessing mechanically improved properties, controlled release rates, and biocompatibility is developing as a focus of the field. More complex drug delivery systems such as multi-drug delivery and combination therapies will be developed based on these advancements. In addition, polymer-based hydrogels are gaining increasing attention in personalized medicine because of their ability to be tailored to a specific patient, for example, drug release rates, drug combinations, target-specific drug delivery, improvement of disease treatment effectiveness, and healthcare cost reduction. Overall, hydrogel application is advancing rapidly, towards more efficient and effective drug delivery systems in the future.

Ellagic Acid Inclusion Complex-Loaded Hydrogels as an Efficient Controlled Release System: Design, Fabrication and In Vitro Evaluation

Oxidants play a crucial role in the development of oxidative stress, which is linked to disease progression. Ellagic acid is an effective antioxidant with applications in the treatment and prevention of several diseases, since it neutralizes free radicals and reduces oxidative stress. However, it has limited application due to its poor solubility and oral bioavailability. Since ellagic acid is hydrophobic, it is difficult to load it directly into hydrogels for controlled release applications. Therefore, the purpose of this study was to first prepare inclusion complexes of ellagic acid (EA) with hydroxypropyl-β-cyclodextrin and then load them into carbopol-934-grafted-2-acrylamido-2-methyl-1-propane sulfonic acid (CP-g-AMPS) hydrogels for orally controlled drug delivery. Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC) were used to validate ellagic acid inclusion complexes and hydrogels. There was slightly higher swelling and drug release at pH 1.2 (42.20% and 92.13%) than at pH 7.4 (31.61% and 77.28%), respectively. Hydrogels had high porosity (88.90%) and biodegradation (9.2% per week in phosphate-buffered saline). Hydrogels were tested for their antioxidant properties in vitro against 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS). Additionally, the antibacterial activity of hydrogels was demonstrated against Gram-positive bacterial strains (Staphylococcus aureus and Escherichia coli) and Gram-negative bacterial strains (Pseudomonas aeruginosa).

Enhanced Solubility and Stability of Aripiprazole in Binary and Ternary Inclusion Complexes Using Hydroxy Propyl Beta Cyclodextrin (HPβCD) and L-Arginine

The low water solubility of an active pharmaceutical ingredient (aripiprazole) is one of the most critical challenges in pharmaceutical research and development. This antipsychotic drug has an inadequate therapeutic impact because of its minimal and idiosyncratic oral bioavailability to treat schizophrenia. The main objective of this study was to improve the solubility and stability of the antipsychotic drug aripiprazole (ARP) via forming binary as well as ternary inclusion complexes with hydroxypropyl-β-cyclodextrin (HPβCD) and L-Arginine (LA) as solubility enhancers. Physical mixing and lyophilization were used in different molar ratios. The developed formulations were analyzed by saturation solubility analysis, and dissolution studies were performed using the pedal method. The formulations were characterized by FTIR, XRD, DSC, SEM, and TGA. The results showcased that the addition of HPβCD and LA inclusion complexes enhanced the stability, in contrast to the binary formulations and ternary formulations prepared by physical mixing and solvent evaporation. Ternary formulation HLY47 improved dissolution rates by six times in simulated gastric fluid (SGF). However, the effect of LA on the solubility enhancement was concentration-dependent and showed optimal enhancement at the ratio of 1:1:0.27. FTIR spectra showed the bond shifting, which confirmed the formation of new complexes. The surface morphology of complexes in SEM studies showed the rough surface of lyophilization and solvent evaporation products, while physical mixing revealed a comparatively crystalline surface. The exothermic peaks in DSC diffractograms showed diminished peaks previously observed in the diffractogram of pure drug and LA. Lyophilized ternary complexes displayed significantly enhanced thermal stability, as observed from the thermograms of TGA. In conclusion, it was observed that the preparation method and a specific drug-to-polymer and amino acid ratio are critical for achieving high drug solubility and stability. These complexes seem to be promising candidates for novel drug delivery systems development.