Inclusion Complexes Research Articles

ENHANCING TRANSDERMAL DELIVERY OF POORLY WATER-SOLUBLE NSAIDS: EFFECTIVE STRATEGIES

Transdermal drug delivery offers significant advantages for administering non-steroidal anti-inflammatory drugs (NSAIDs) and anti-complementary drugs, particularly those with poor water solubility. This delivery route bypasses first-pass metabolism and gastrointestinal degradation, enhancing bioavailability and patient compliance. However, the stratum corneum, the outermost layer of the skin, poses a formidable barrier to drug permeation. To address this challenge, several innovative strategies have been developed to improve the transdermal delivery of these poorly soluble drugs. Chemical enhancers, such as alcohols, fatty acids, and surfactants, can disrupt the lipid structure of the stratum corneum, increasing drug solubility and permeability. Nanoformulations, including liposomes, niosomes, solid lipid nanoparticles, and nanoemulsions, enhance drug solubility, provide protection against degradation, and facilitate controlled release with deeper skin penetration. Prodrugs, designed to convert into the active drug within the skin, can improve solubility and permeability. Physical methods like microneedles, iontophoresis, and phonophoresis create micropores or use electrical and ultrasound waves to enhance permeation without compromising skin integrity. Cyclodextrins form inclusion complexes with drugs, boosting solubility and stability. Hydrogels and polymer-based formulations create a moist environment for sustained drug release and better absorption. Co-solvents and surfactants, such as ethanol and DMSO, further enhance solubility and disrupt the stratum corneum to facilitate drug penetration. Electroporation and thermal ablation transiently disrupt the skin barrier, significantly improving drug permeation. These strategies, individually or in combination, hold promise for optimizing the transdermal delivery of poorly water-soluble NSAIDs and anticomplementary drugs, ensuring effective therapeutic outcomes and improved patient compliance.

Enhancing Cannabinoid Bioavailability in Pain Management: The Role of Cyclodextrins

Chronic pain (CP), including pain related to cancer, affects approximately 2 billion people worldwide, significantly diminishing quality of life and imposing socio-economic burdens. Current treatments often provide limited relief and may cause adverse effects, demanding more effective alternatives. Natural compounds from Cannabis sativa L., particularly cannabinoids like THC and CBD, exhibit analgesic and anti-inflammatory properties, but their therapeutic use is restricted by poor solubility and low bioavailability. Cyclodextrins (CDs) and cyclic oligosaccharides may encapsulate hydrophobic drugs in order to enhance their solubility and stability, offering a promising solution to these challenges. This study explores the formation of CD inclusion complexes with cannabinoids and specific terpenes, such as D-limonene (LIM), beta-caryophyllene (BCP), and gamma-terpinene (γ-TPN), aiming to improve pharmacokinetic profiles and therapeutic efficacy. We discuss analytical techniques for characterizing these complexes and their mechanisms of action, highlighting the potential of CDs to optimize drug formulations. The integration of CDs in cannabinoid therapies may enhance patient compliance and treatment outcomes in CP management. Future research should focus on innovative formulations and delivery systems to maximize the clinical applications of those compounds.

Cyclodextrins: Advances in Chemistry, Toxicology, and Multifaceted Applications

Cyclodextrins (CDs) have garnered significant attention in various scientific and industrial fields due to their unique ability to form inclusion complexes with a wide range of guest molecules. This review comprehensively explores the latest advancements in cyclodextrin chemistry, focusing on the synthesis and characterization of cyclodextrin derivatives and their inclusion complexes. This review examines the biological activities of cyclodextrins, highlighting their pharmacological properties and pharmacokinetics, and discussing their promising applications in drug delivery systems. Furthermore, the industrial utilization of cyclodextrins, including their role in nanomaterials and nanostructured coatings, as well as their potential in environmental remediation, are explored. The present research also addresses the critical aspect of toxicity, particularly concerning cyclodextrin inclusion complexes, providing an overview of the current understanding and safety considerations. Through a multidisciplinary approach, the aim is to present a complete view of cyclodextrins, underscoring their versatility and impact across various domains.

Development of ion-triggered in situ gel containing ketoconazole/hydroxypropyl-β-cyclodextrin for ocular delivery: in vitro and in vivo evaluation

The application of ketoconazole (KET) in ocular drug delivery is restricted by its poor aqueous solubility though its broad-spectrum antifungal activity. The aim of this study is to develop an ion-sensitive in situ gel (ISG) of KET to promote its ocular bioavailability in topical application. The solubility of KET in water was increased by complexation with hydroxypropyl-β-cyclodextrin (HPβCD), then KET-HPβCD inclusion complex (KET-IC) was fabricated into an ion-sensitive ISG triggered by sodium alginate (SA). The in vitro drug release and antifungal activities investigations demonstrated that the KET-IC-ISG formulation increased drug release and anti-fungal activities compared to pure KET. The ex vivo rabbit corneal permeation studied demonstrated higher permeability of KET-IC-ISG formulation (Papp of (6.34 ± 0.21) × 10−4 cm/h) than pure KET (Papp of (3.09 ± 0.09) × 10−4 cm/h). The cytotoxicity assay and the ocular irritation study in rabbits confirmed the KET-IC-ISG safety and well tolerance. The ocular pharmacokinetics of KET in rabbits was investigated and the results showed that the KET-IC-ISG increased its bioavailability in cornea by 47-fold. In conclusion, the KET-IC-ISG system promoted the precorneal retention, the ocular drug bioavailability and the developed formulation is a potential strategy to treat mycotic keratitis.

Dendritic Molecular Baskets for Selective Binding of Toxic Methotrexate.

We describe the preparation, assembly, recognition characteristics, and bioactivity of dendritic basket 612-. This novel cavitand has a deep aromatic pocket with three (S)-glutamic acid dendrons at the rim to amplify water solubility and prevent self-association. 1H NMR spectroscopy, calorimetry (ITC), and mass spectrometry (ESI-MS) measurements validate the formation of an inclusion complex between 612- and anticancer drug methotrexate (MTX2-) in water (Kd = 9.2 μM). To identify the docking pose, a comparison of computed (DFT and MM) and experimental 1H NMR chemical shifts suggests that MTX2- folds inside 612- (π···π), forming HBs with the peptidic dendrons while anchoring (C-H···π) to the aromatic pocket through its N-methyl group. In consequence, 612- selectively binds MTX2- in competition with structurally similar folic acid and leucovorin (reversal poisoning agent). While the host is biocompatible (HEK293; IC50 > 150 μM) and produces inclusion complex [MTX⊂6]14- in cell media, it experiences limitation in pharmacokinetic sequestration of MTX2- as dihydrofolate reductase's affinity to the drug is suggested to prevail over that of 612-. Nonetheless, considering the basket's biocompatibility, tunability, and chemoselectivity, it stands as the leading candidate in the pursuit of an effective abiotic antidote for methotrexate poisoning.

Dendritic Molecular Baskets for Selective Binding of Toxic Methotrexate

We describe the preparation, assembly, recognition characteristics, and bioactivity of dendritic basket 612‐. This novel cavitand has a deep aromatic pocket with three (S)‐glutamic acid dendrons at the rim to amplify water solubility and prevent self‐association. 1H NMR spectroscopy, calorimetry (ITC), and mass spectrometry (ESI‐MS) measurements validate the formation of an inclusion complex between 612‐ and anticancer drug methotrexate (MTX2‐) in water (Kd = 9.2 μM). To identify the docking pose, a comparison of computed (DFT and MM) and experimental 1H NMR chemical shifts suggests that MTX2‐ folds inside 612‐ (π···π), forming HBs with the peptidic dendrons while anchoring (C−H···π) to the aromatic pocket through its N‐methyl group. In consequence, 612‐ selectively binds MTX2‐ in competition with structurally similar folic acid and leucovorin (reversal poisoning agent). While the host is biocompatible (HEK293; IC50 > 150 μM) and produces inclusion complex [MTX⊂6]14‐ in cell media, it experiences limitation in pharmacokinetic sequestration of MTX2‐ as dihydrofolate reductase’s affinity to the drug is suggested to prevail over that of 612‐. Nonetheless, considering the basket’s biocompatibility, tunability, and chemoselectivity, it stands as the leading candidate in the pursuit of an effective abiotic antidote for methotrexate poisoning.

An environmentally safe formulation of plant derived fungicide: preparation and characterization of inclusion complex of honokiol and methyl-β-cyclodextrin

An environmentally safe formulation of plant derived fungicide: preparation and characterization of inclusion complex of honokiol and methyl-β-cyclodextrin

Cyclodextrin Dimers Functionalized with Biotin as Nanocapsules for Active Doxorubicin Delivery Against MCF-7 Breast Cell Line.

Cyclodextrin dimers have been investigated as potential nanocapsules of biomolecules. The presence of two cavities can improve the stability of inclusion complexes, working as a hydrophilic sandwich of poorly water-soluble species. Here, we designed new β- and γ-cyclodextrin dimers functionalized with biotin as a targeting unit and tested the new bioconjugates as doxorubicin delivery systems in cancer cells. Biotin can recognize the Sodium-dependent Multivitamin Transporter (SMVT) receptor, encoded by the Solute Carrier Family 5 Member 6 (SLC5A6) gene and improve the uptake of drugs. We evaluated the expression of the SLC5A6 transcript in human cell lines to select the best cell model (MCF-7) for the in vitro studies. Furthermore, in the cell lines, we investigated the transcript levels of genes correlated to biotin cell availability, Holocarboxylase Synthetase (or HCS encoded by HLCS gene) and Biotinidase (encoded by BTD gene) enzymes. Moreover, the expression of ATP Binding Cassette Subfamily G Member 2 transporter (encoded by ABCG2 gene), which may play a role in doxorubicin resistance, has been investigated. The antiproliferative activity of the doxorubicin complexes with the dimers has been determined to study the effect of the biotin moiety on the cytotoxicity in MCF-7 cancer cells.

Efficient Loading into and Controlled Release of Lipophilic Compound from Liposomes by Using Cyclodextrin as Novel Trapping Agent.

Lipid bilayer vesicles, liposomes are representative drug delivery carriers. High encapsulation efficiency and release control of drugs are essential for clinical application of liposomes. For efficient drug loading into liposomes, remote loading method using driving force like transmembrane gradients of pH and ions are utilized. Ions are called as "trapping agents," which are also critical for the controlled release of drugs loaded into liposomes inside. It is difficult to apply ions as trapping agents to various drugs because of limited physicochemical compatibility between drugs and ions. Cyclodextrins (CDs) with hydrophobic cavity can make inclusion complexes with various hydrophobic compounds. Therefore, we aimed to evaluate the potential of CDs as a novel trapping agent using sulfobutylether-β-cyclodextrin (SBE-β-CD) and ibuprofen (IB), a weak acid hydrophobic drug. Encapsulation efficiency of IB in liposomes with pH gradient was approximately 27%, and it was enhanced by intraliposomal SBE-β-CD inclusion in addition to pH gradient, which was SBE-β-CD concentration-dependent. In liposomes with pH gradient, a large fraction of IB was released in a short time. This early-stage rapid IB release was significantly suppressed by the inclusion of SBE-β-CD inside liposomes. Thus, novel remote loading technology by intraliposomal SBE-β-CD enabled the efficient encapsulation of the hydrophobic drug into the aqueous phase of liposomes as well as their controlled release. This technology should be applied to various drugs that can be included into CDs in order to enhance their therapeutic benefits.

DEVELOPMENT AND EVALUATION OF CYCLODEXTRIN NANOSPONGES-BASED TOPICAL FORMULATION OF TAZAROTENE

Objective: Tazarotene is used as a topical retinoid for the treatment of acne, psoriasis and sun-damaged skin. But its topical formulation has many side effects, including itching, burning, dryness, redness, stinging, rash blistering, skin discoloration, peeling at the site of application and low bioavailability. The present study focuses on the reduction of side effects and enhancement of solubility and topical bioavailability of tazarotene by using cyclodextrin-based nanosponges. Methods: Nanosponge of tazarotene were prepared by lyophilization method. The physiochemical characterization of plain nanosponges and drug-loaded nanosponges were performed using Fourier Transform Infrared Spectroscopy (FTIR), Differential Scanning Calorimetry (DSC), and X-ray Diffractometer (XRD) studies. The drug-loaded nanosponges were incorporated into a carpool-based gel formulation. The prepared formulation was evaluated for viscosity, dissolution and stability. FTIR, DSC and XRD studies confirmed the formation of inclusion complex of tazarotene with nanosponges. Results: The particle size of the drug-loaded nanosponges was found to be in the range of 156.72 to 163.48 nm. Transmission Electron Microscopy (TEM) images revealed the regular spherical shape of both the nanosponges that are unaffected even after drug encapsulation. The pH of the gel formulations was found to be in the range of 5.86 to 6.46. The gel formulation resulted in the diffusion of drug in controlled manner for up to 24 h. The in vitro dissolution studies revealed that nanosponges-based topical formulation had better results than the marketed product. Conclusion: Thus, the study showed that nanosponge-based gel formulation can be a possible alternative to conventional formulations of tazarotene with enhanced bioavailability and skin retention characteristics for topical application.

Chalcogen Bond-Driven Alkylations: Selenoxide-Pillar[5]arene As A Recyclable Catalyst For Displacement Reactions In Water.

A novel strategy to catalyze alkylation reactions through chalcogen bond interaction using a supramolecular structure is presented herein. Utilizing just 1.0 mol% of selenoxide-pillar[5]arene (P[5]SeO) as the catalyst we achieved efficient catalysis in the cyanation of benzyl bromide in water. Our approach demonstrated high efficiency and effectiveness, with the results supported by designed control experiments and theoretical models, highlighting the catalytic effect of the pillar[5]arene through noncovalent interactions. Quantum-chemical calculations (ωB97X-D/def2-TZVP@SMD) pointed out that the catalyzed cyanation reaction followed an SN2-like mechanism, with energy barriers (ΔH‡) ranging from 16.7 to 18.2 kcal mol-1, exhibiting dissociative character depending on the para-substituent. 1H NMR analysis revealed that P[5]SeO acted as a catalyst through inclusion complex formation, facilitating the transfer of the electrophilic substrate to the aqueous solution for nucleophilic displacement. Our reaction protocol proved applicable to various substrates, including aromatic and alpha-carbonyl derivatives. The use of sodium azide as the nucleophile was also feasible. Importantly, our method allowed scalability, and the catalyst P[5]SeO could be recovered and reused effectively for multiple reaction cycles, showcasing sustainability.

Screening and inclusion of luteolin for β-cyclodextrin: molecular simulations and experiments

In this study, we first established a guest small molecule screening mechanism by molecular simulation, and then screened lignans from 10 polyphenolic compounds to identify the most suitable guest molecule for encapsulation with β-cyclodextrin (β-CD). Subsequently, the subject-guest interactions and encapsulation mechanisms of lignans with β-CD, 2-hydroxypropyl-cyclodextrin (HP-β-CD) and 2,6-dimethyl-cyclodextrin (DM-β-CD) were investigated using a combination of molecular simulation and experimental methods, respectively. Molecular simulations were performed to calculate the microstructural parameters, including solubility parameters, binding energies, and mean square displacements. The simulation results demonstrated that DM-β-CD exhibited the strongest interaction with luteolin and formed the most stable inclusion complex. The inclusion complexes of luteolin with the three cyclodextrins were prepared by freeze-drying method, and the formation of the inclusion complexes was demonstrated using infrared spectroscopy (FTIR), X-ray diffraction (XRD), differential scanning calorimetry (DSC) and ultraviolet-visible spectroscopy (UV). Phase solubility studies confirmed the formation of 1:1 stoichiometric inclusion complexes of lignans with cyclodextrins. Furthermore, 2,2-diphenyl-1-pyridine hydrazine (DPPH) free radical scavenging experiments demonstrated that the inclusion complexes exhibited enhanced antioxidant capacity. In light of these findings, it can be concluded that among the three cyclodextrins, DM-β-CD was optimally encapsulated with luteolin.

Deep Eutectic Solvents for Next-generation Cyclodextrin Science

Abstract In cyclodextrin science, water has been almost exclusively employed as solvent, and this imposes non-negligible limitations to the scope of applications. Accordingly, deep eutectic solvents, constructed from hydrogen-bonding donors and acceptors, have been attracting much interest as important substitutes of water. This review comprehensively covers chemical and physicochemical features of cyclodextrins in these eco-friendly solvents. In one category, cyclodextrins or their derivatives are dissolved as solutes in conventional deep eutectic solvents. All of α-, β-, and γ-cyclodextrins efficiently form inclusion complexes with various guest molecules, exactly as observed in water. Notably, chemically modified cyclodextrins (e.g., 2-hydroxypropyl-cyclodextrins) form still more stable inclusion complexes than native cyclodextrins. Alternatively, deep eutectic solvents are prepared by combining cyclodextrins with other hydrogen-bonding components. The cyclodextrin units in these mixtures also form inclusion complexes with guest molecules. It has been proposed that enhanced flexibility of cylindrical structures of cyclodextrins allows effective induced-fit to stabilize inclusion complexes. The applications of these systems widely range from catalysis for organic synthesis to extraction, analysis, pharmaceutics, and many other fields. High solubilities of CDs and various chemicals in these solvents guarantee high productivity of target transformation, and unprecedentedly novel functions are promising for these unique systems.

Enhancing orofacial pain relief: α-phellandrene complexed with hydroxypropyl-β-cyclodextrin mitigates orofacial nociception in rodents.

Orofacial pain affects 10-15% of adults and can severely impact quality of life. Despite ongoing treatment challenges, monoterpene alpha-phellandrene (PHE) shows potential therapeutic benefits. This study aimed to develop and evaluate an inclusion complex of PHE with hydroxypropyl-beta-cyclodextrin (PHE-HPβCD) for treating orofacial pain. The PHE-HPβCD complex was created using physical mixing and characterized by differential scanning calorimetry (DSC) and high-performance liquid chromatography (HPLC) to determine encapsulation efficiency. The complex exhibited a 70.45% encapsulation efficiency. Male Swiss mice were used in models of orofacial pain induced by formalin, cinnamaldehyde, glutamate, and corneal nociception by hypertonic saline. Additionally, cytokine levels (TNF-α and IL-1β) were measured in the upper lip tissue of mice subjected to the formalin model. Both PHE and PHE-HPβCD showed significant antinociceptive effects at a 50mg/kg dose during formalin-induced pain, reducing both neurogenic and inflammatory phases of pain. PHE-HPβCD also reduced TNF-α and IL-1β levels. For cinnamaldehyde and glutamate-induced nociception, both treatments reduced pain behavior, but only PHE-HPβCD decreased eye wipes in corneal nociception. These results suggest that PHE, especially in complexed form, alleviates orofacial pain by potentially modulating pain-related receptors (TRPA1 and TRPV1), mediators, like glutamate, and reducing pro-inflammatory cytokines. Further research is needed to explore the precise mechanisms of PHE in chronic orofacial pain models, but the study indicates promising avenues for new pain treatments.

Exploring the interaction of curcumin with β-cyclodextrin and its binding with DNA: A combined spectroscopic and molecular docking study

At present, a major effort in biophysical studies has been paid towards exploring the interactions and release of therapeutic payloads to the specific site leaving behind healthy cells unaffected and hence, lower the drug-induced toxicity. For the purpose, interaction of β-bound CUR with calf thymus DNA (ctDNA) has been examined intensely using a series of biophysical methods like absorption, steady state fluorescence emission, and circular dichroism together with molecular docking study. The experimental analysis divulge that CUR interacts with both β–CD (although with different molar ratio) and DNA. However, the binding affinity of CUR with the target (DNA) is higher than it does with the β–CD. When β–CD-carried (10 mM) CUR (μM) (inclusion complex) comes near DNA (15–372 μM), CUR gets out from β–CD's void and approaches to binds with the DNA. The relocation of the probe occurred due to competitive binding of the CUR between β–CD and the DNA. The present investigation may provide a simple yet probable route for the transfer of encapsulated therapeutic payload of β–CD to the most relevant biomolecular target DNA.

Baicalin nanofiber membranes: A comprehensive study on preparation, characterization, and antimicrobial pharmacological activities

Baicalin is a natural active ingredient known for its medicinal properties and a broad spectrum of pharmacological activities, including antimicrobial, antioxidant, antiviral, and anticancer effects. However, its application is hindered by its poor water-solubility. In this study, we aimed to enhance the water solubility of baicalin by embedding it within the hydrophobic cavity of hydroxypropyl-β-cyclodextrin through supramolecular assembly to form inclusion complexes. The inclusion complexes were subsequently processed into nanofiber membranes suitable for application on skin and wounds using coaxial electrostatic spinning. The inclusion complexes and nanofiber membranes were analyzed and characterized using high-performance liquid chromatography (HPLC), X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The combined results from XRD, FT-IR, and TGA confirmed that baicalin successfully formed inclusion complexes with cyclodextrin, resulting in an increase in water solubility from 0.0170 mg/mL to 8.9600 mg/mL, representing a 527-fold enhancement. Additionally, the inclusion complexes demonstrated superior antimicrobial activity against E. coli, S. aureus and C. albicans, as well as higher free radical scavenging rates compared to native baicalin. After the inclusion complexes were transformed into nanofiber membranes via coaxial electrospinning, their properties remained unchanged, and they continued to exhibit excellent antimicrobial and antioxidant activities. In the in vitro release assay, nearly 90% of the drug (baicalin) was released from the nanofiber membranes over a period of time, indicating sustained release. Furthermore, the molecular docking mechanism of baicalin and cyclodextrin was elucidated through molecular docking simulations, establishing a theoretical foundation for the synthesis of inclusion complexes in the computational studies. This study reports the successful fabrication of water-soluble, antimicrobial nanofiber membranes containing bioavailable baicalin, which have potential clinical applications in the development of wound dressings and drug delivery systems utilizing plant-extracted bioactive compounds.

Parallel (competitive) reactions of micelle formation and cyclodextrin–surfactant inclusion complex formation in aqueous solution: A consequence of the Gibbs–Duhem equation—invariance of the mass action law and the possibility of determining the equilibrium constant of the inclusion complex

The Gibbs–Duhem equation results in the independence between the standard Gibbs free energy of micelle formation and the standard Gibbs free energy of monocomponent surfactant’s and cyclodextrin’s (CD’s) inclusion complex formation in aqueous solution. The experimental data show that the surfactant’s critical micellar concentration increases in the presence of CD. At a constant temperature, the standard Gibbs free energy of micelle formation remains constant, irrespective of the presence of parallel competitive processes such as inclusion complex formation. This indicates that the critical micellar concentration remains unchanged at the corresponding concentration scale. As a result, the equilibrium constant for surfactant–CD inclusion complex formation can be determined by changing the critical micellar concentration in the presence and absence of CD. A graphical method for determining the equilibrium constant of the inclusion complex is also presented. An analytical approach for analyzing the influence of the formation of the inclusion complex with CD on the formation of the binary mixed micellar pseudophase is presented. Suppose that different values exist for the equilibrium constants of the formation of the inclusion complex for two surfactants from their binary mixture. In this case, there is a change in the initial mole fraction from the initial mixture of surfactants, which should be considered when applying the regular solution theory protocol when determining the parameters of a binary mixed micelle in the presence of CD.

Polycaprolactone/polylactic acid nanofibers incorporated with butyl hydroxyanisole /HP-β-CD assemblies for improving fruit storage quality.

In this study, the inclusion complex was prepared with butyl hydroxyanisole (BHA) as the functional substance and 2-hydroxypropyl beta-cyclodextrin (HP-β-CD) as the main molecule by ultrasound mediation. The inclusion complex was mixed with polycaprolactone (PCL)/polylactic acid (PLA), and nanofiber films loaded with different concentrations of BHA/HP-β-CD inclusion complex were prepared by electrospinning for fruit preservation. The scanning electron microscopy and infrared spectroscopy characterization results showed that HP-β-CD successfully embedded BHA in the cavity. The encapsulation of BHA increases the fiber diameter and thermal stability and decreases the crystallinity and hydrophobicity. The oxidation resistance experiment showed that the nanofiber film had a strong free radical scavenging ability. The BHA release rate of the nanofiber membrane was determined by high-performance liquid chromatography, and the release curve results showed that the inclusion complex prepared by ultrasonic self-assembly could significantly prolong the BHA release time. In addition, nanofiber films containing inclusion complex showed an effective fresh-keeping effect within 7 days of mango storage. In conclusion, a series of characterization tests show that the nanofiber film prepared in this study has a good market prospect in food preservation.

A dissolving microneedle patch loaded with plumbagin/hydroxypropyl-β-cyclodextrin inclusion complex for infected wound healing

Treating infected wounds is facing a serious challenge due to the rapid spread of antibiotic resistance worldwide. In the search for novel antimicrobial drugs, natural products often serve as a crucial resource. Plumbagin (PLB) is the most important natural active ingredient in the root of Plumbago zeylanica L. known for its excellent antibacterial ability. However, the application of PLB is limited because of its poor water solubility, instability, and tendency to sublimate. In this study, we propose a solution by designing a hyaluronic acid (HA)/polyvinylpyrrolidone (PVP) dissolving microneedle patch loaded with PLB/hydroxypropyl-β-cyclodextrin (HP-β-CD) inclusion complex. PLB was encapsulated into the cavity of HP-β-CD to improve its solubility and stability using the neutralization agitation method. The formation of the inclusion complex significantly increased the water solubility of PLB to 1350 ± 6.8 μg/mL, which is 17 times higher than its original value of 79.3 ± 1.7 μg/mL. The encapsulation efficiency was found to be 94.82 ± 3.34%. In vitro drug release studies, PLB microneedles loaded with PLB/HP-β-CD inclusion complex rapidly released into PBS within 15min. Furthermore, the PLB microneedles exhibited strong antibacterial activity against Staphylococcus aureus (S. aureus) both in vivo and in vitro. They also remarkably accelerated the healing of infected wounds in mice by enhancing collagen deposition and re-epithelialization, reducing inflammation, and stimulating angiogenesis. Overall, this multifunctional microneedle patch shows promising potential for clinical applications in the healing of infected wounds.

Probing host guest inclusion complex and its applications by biophysical approach subsequently optimized by molecular docking

Herein, we explored the construction of a supramolecular encapsulated complex between Nile blue (NB) and p-sulfonatothiacalix[4]arene (TSC4X). The developed inclusion complex (NB-TSC4X) was established by fluorescence spectroscopy, TGA, FTIR, 1H NMR, and DFT studies. Benesi-Hildebrand calculation showed a linear plot that indicated a 1:1 stoichiometric ratio having a fairly high stability constant of 2720 M−1 in the solution phase. DFT analysis helps us to find out the optimized structure of the inclusion complex. Finally, the binding interaction of the inclusion complex with bovine serum albumin (BSA) was evaluated. In brief, this work uncloses a new strategy to enhance the performance of fluorescent dye.