Hydroxypropyl-β-cyclodextrin functionalized calcium carbonate microparticles as a potential carrier for enhancing oral delivery of water-insoluble drugs

Nanosuspension-Loaded Dissolving Microneedle Patches for Enhanced Transdermal Delivery of a Highly Lipophilic Cannabidiol

Purpose

Transdermal Drug Delivery System (TDDS) offers a promising alternative for delivering poorly soluble drugs, challenged by the stratum corneum's barrier effect, which restricts the pool of drug candidates suitable for TDDS. This study aims to establish a delivery platform specifically for highly lipophilic drugs requiring high doses (log P > 5, dose > 10 mg/kg/d), to improve their intradermal delivery and enhance solubility.

Methods

Cannabidiol (CBD, log P = 5.91) served as the model drug. A CBD nanosuspension (CBD-NS) was prepared using a bottom-up method. The particle size, polydispersity index (PDI), zeta potential, and concentration of the CBD-NS were characterized. Subsequently, CBD-NS was incorporated into dissolving microneedles (DMNs) through a one-step manufacturing process. The intradermal dissolution abilities, physicochemical properties, mechanical strength, insertion depth, and release behavior of the DMNs were evaluated. Sprague-Dawley (SD) rats were utilized to assess the efficacy of the DMN patch in treating knee synovitis and to analyze its skin permeation kinetics and pharmacokinetic performance.

Results

The CBD-NS, stabilized with Tween 80, exhibited a particle size of 166.83 ± 3.33 nm, a PDI of 0.21 ± 0.07, and a concentration of 46.11 ± 0.52 mg/mL. The DMN loaded with CBD-NS demonstrated favorable intradermal dissolution and mechanical properties. It effectively increased the delivery of CBD into the skin, extended the action's duration in vivo, and enhanced bioavailability. CBD-NS DMN exhibited superior therapeutic efficacy and safety in a rat model of knee synovitis, significantly inhibiting TNF-α and IL-1β compared with the methotrexate subcutaneous injection method.

Conclusion

NS technology effectively enhances the solubility of the poorly soluble drug CBD, while DMN facilitates penetration, extends the duration of action in vivo, and improves bioavailability. Furthermore, CBD has shown promising therapeutic outcomes in treating knee synovitis. This innovative drug delivery system is expected to offer a more efficient solution for the administration of highly lipophilic drugs akin to CBD, thereby facilitating high-dose administration.

Exploiting Benefits of Vaterite Metastability to Design Degradable Systems for Biomedical Applications

The widespread application of calcium carbonate is determined by its high availability in nature and simplicity of synthesis in laboratory conditions. Moreover, calcium carbonate possesses highly attractive physicochemical properties that make it suitable for a wide range of biomedical applications. This review provides a conclusive analysis of the results on using the tunable vaterite metastability in the development of biodegradable drug delivery systems and therapeutic vehicles with a controlled and sustained release of the incorporated cargo. This manuscript highlights the nuances of vaterite recrystallization to non-porous calcite, dissolution at acidic pH, biodegradation at in vivo conditions and control over these processes. This review outlines the main benefits of vaterite instability for the controlled liberation of the encapsulated molecules for the development of biodegradable natural and synthetic polymeric materials for biomedical purposes.

Mesoporous silica nanoparticles adsorb aflatoxin B1 and reduce mycotoxin-induced cell damage

The present study examined the effects of mesoporous silica nanoparticles (MSNs) on its adsorption capacity of aflatoxin B₁ (AFB₁). Moreover, the study evaluated the toxicity of MSNs with AFB₁ using NIH3T3 cells and hemolysis test. The obtained MSNs were spherical, irregular-like in shape, having a mean size of 39.97 ± 7.85 nm and a BET surface area of 1195 m²/g. At 0.1 mg mL^-1 concentration of MSN, the AFB₁ adsorption capacity was 30%, which reached 70% when the MSN concentration increased to 2.0 mg mL^-1. Our findings showed that AFB₁ was adsorbed (∼67%) in the first few minutes on being in contact with MSNs, reaching an adsorption capacity of ∼70% after 15 min. Thereafter, the adsorption capacity remained constant in solution, demonstrating that the MSNs adsorbed toxins even beyond overnight. MSN treatment (0.5-2.0 mg mL^-1) using NIH3T3 cells did not result in any reduction in cell viability. In addition, MSN treatment completely reversed the cytotoxic effect of AFB₁ at all concentrations. Hemolysis test also revealed no hemolysis in MSNs evaluated alone and in those combined with AFB₁. To the best of our knowledge, this study is the first to demonstrate that MSN can reduce cell toxicity produced by AFB₁ due to its potential to adsorb mycotoxins.

Safety of inhaled ivermectin as a repurposed direct drug for treatment of COVID-19: A preclinical tolerance study

Introduction

SARS-CoV-2 replication in cell cultures has been shown to be inhibited by ivermectin. However, ivermectin's low aqueous solubility and bioavailability hinders its application in COVID-19 treatment. Also, it has been suggested that best outcomes for this medication can be achieved via direct administration to the lung.

Objectives

This study aimed at evaluating the safety of a novel ivermectin inhalable formulation in rats as a pre-clinical step.

Methods

Hydroxy propyl-β-cyclodextrin (HP-β-CD) was used to formulate readily soluble ivermectin lyophilized powder. Adult male rats were used to test lung toxicity for ivermectin-HP-β-CD formulations in doses of 0.05, 0.1, 0.2, 0.4 and 0.8 mg/kg for 3 successive days.

Results

The X-ray diffraction for lyophilized ivermectin-HP-β-CD revealed its amorphous structure that increased drug aqueous solubility 127-fold and was rapidly dissolved within 5 s in saline. Pulmonary administration of ivermectin-HP-β-CD in doses of 0.2, 0.4 and 0.8 mg/kg showed dose-dependent increase in levels of TNF-α, IL-6, IL-13 and ICAM-1 as well as gene expression of MCP-1, protein expression of PIII-NP and serum levels of SP-D paralleled by reduction in IL-10. Moreover, lungs treated with ivermectin (0.2 mg/kg) revealed mild histopathological alterations, while severe pulmonary damage was seen in rats treated with ivermectin at doses of 0.4 and 0.8 mg/kg. However, ivermectin-HP-β-CD formulation administered in doses of 0.05 and 0.1 mg/kg revealed safety profiles.

Conclusion

The safety of inhaled ivermectin-HP-β-CD formulation is dose-dependent. Nevertheless, use of low doses (0.05 and 0.1 mg/kg) could be considered as a possible therapeutic regimen in COVID-19 cases.

Encapsulation of Low-Molecular-Weight Drugs into Polymer Multilayer Capsules Templated on Vaterite CaCO3 Crystals

Polyelectrolyte multilayer capsules (PEMCs) templated onto biocompatible and easily degradable vaterite CaCO₃ crystals via the layer-by-layer (LbL) polymer deposition process have served as multifunctional and tailor-made vehicles for advanced drug delivery. Since the last two decades, the PEMCs were utilized for effective encapsulation and controlled release of bioactive macromolecules (proteins, nucleic acids, etc.). However, their capacity to host low-molecular-weight (LMW) drugs (<1–2 kDa) has been demonstrated rather recently due to a limited retention ability of multilayers to small molecules. The safe and controlled delivery of LMW drugs plays a vital role for the treatment of cancers and other diseases, and, due to their tunable and inherent properties, PEMCs have shown to be good candidates for smart drug delivery. Herein, we summarize recent progress on the encapsulation of LMW drugs into PEMCs templated onto vaterite CaCO₃ crystals. The drug loading and release mechanisms, advantages and limitations of the PEMCs as LMW drug carriers, as well as bio-applications of drug-laden capsules are discussed based upon the recent literature findings.

Porous Inorganic and Hybrid Systems for Drug Delivery: Future Promise in Combatting Drug Resistance and Translation to Botanical Applications

BACKGROUND

Porous micro- and nanoparticles have the capacity to encapsulate a large quantity of therapeutics, making them promising delivery vehicles for a variety of applications. This review aims to highlight the latest development of inorganic and hybrid (inorganic/ organic) particles for drug delivery with an additional emphasis on combatting drug resistant cancer. We go one step further and discuss delivery applications beyond medicinal delivery, as there is generally a translation from medicinal delivery to botanic delivery after a short lag time.

METHODS

We undertook a search of relevant peer-reviewed publications. The quality of the relevant papers was appraised using standard tools. The characteristics of the papers are described herein, and the relevant material and therapeutic properties are discussed.

RESULTS

We discuss 4 classes of porous particles in terms of drug delivery and theranostics. We specifically focus on silica, calcium carbonate, metal-phenolic network, and metalorganic framework particles. Other relevant biomedically relevant applications are discussed and we highlight outstanding therapeutic results in the relevant literature.

CONCLUSION

The findings of this review confirm the importance of studying and utilizing porous particles for therapeutic delivery. Moreover, we show that the properties of porous particles that make them promising for medicinal drug delivery also make them promising candidates for agro-industrial applications.

Ground Calcium Carbonate as a Low Cost and Biosafety Excipient for Solubility and Dissolution Improvement of Praziquantel

Calcium carbonate is an abundant mineral with several advantages to be a successful carrier to improve oral bioavailability of poorly water-soluble drugs, such as praziquantel. Praziquantel is an antiparasitic drug classified in group II of the Biopharmaceutical Classification System hence characterized by high-permeability and low-solubility. Therefore, the dissolution rate is the limiting factor for the gastrointestinal absorption that contributes to the low bioavailability. Consequently, the therapeutic dose of the praziquantel must be high and big tablets and capsules are required, which are difficult to swallow, especially for pediatric and elderly patients. Mixtures of praziquantel and calcium carbonate using solid-solid physical mixtures and solid dispersions were prepared and characterized using several techniques (X-ray diffraction differential scanning calorimetry, thermogravimetric analysis, scanning electron microscopy, laser diffraction, Fourier transform infrared and Raman spectroscopies). Solubility of these formulations evidenced that the solubility of praziquantel-calcium carbonate interaction product increased in physiological media. In vitro dissolution tests showed that the interaction product increased the dissolution rate of the drug in acidic medium. Theoretical models were studied to understand this experimental behavior. Cytotoxicity and cell cycle studies were performed, showing that praziquantel-calcium carbonate physical mixture and interaction product were biocompatible with the HTC116 cells, because it did not produce a decrease in cell viability or alterations in the cell cycle.

Highly Soluble Glimepiride and Irbesartan Co-amorphous Formulation with Potential Application in Combination Therapy

One-third of the population of the USA suffers from metabolic syndrome (MetS). Treatment of patients with MetS regularly includes drugs prescribed simultaneously to treat diabetes and cardiovascular diseases. Therefore, the development of novel multidrug formulations is recommended. However, the main problem with these drugs is their low solubility. The use of binary co-amorphous systems emerges as a promising strategy to increase drug solubility. In the present study, irbesartan (IBS) and glimepiride (GMP), class II active pharmaceutical ingredients (API), widely used in the treatment of arterial hypertension and diabetes, were selected to develop a novel binary co-amorphous system with remarkable enhancement in the dissolution of both APIs. The phase diagram of IBS-GMP was constructed and co-amorphous systems were prepared by melt-quench, in a wide range of compositions. Dissolution profile (studied at pH 1.2 and 37°C for mole fractions 0.01, 0.1, and 0.5) demonstrated that the x_GMP = 0.01 formulation presents the highest enhancement in its dissolution. GMP went from being practically insoluble to reach 3.9 ± 0.9 μg/mL, and IBS showed a 12-fold increment with respect to the dissolution of its crystalline form. Infrared studies showed that the increase in the dissolution profile is related to the intermolecular interactions (hydrogen bonds), which were dependent of composition. Results of structural and thermal characterization performed by XRD and DSC showed that samples have remained in amorphous state for more than 10 months of storage. This work contributes to the development of a highly soluble co-amorphous drugs with potential used in the treatment of MetS.

Calcium-based biomaterials for diagnosis, treatment, and theranostics

Calcium-based biomaterials with good biosafety and bio-absorbability are promising for biomedical applications such as diagnosis, treatment, and theranostics.

Evaluation of the potential toxicity of unmodified and modified cyclodextrins on murine blood-brain barrier endothelial cells

In this study, we investigated the cytotoxic effects of unmodified α-cyclodextrin (α-CD) and modified cyclodextrins, including trimethyl-β-cyclodextrin (TRIMEB) and hydroxypropyl-β-cyclodextrin (HPβCD), on immortalized murine microvascular endothelial (cEND) cells of the blood-brain barrier (BBB). A CellTiter-Glo viability test, performed on the cEND cells showed significant differences among the different cyclodextrins. After 24 hr of incubation, TRIMEB was the most cytotoxic, and HPβCD was non-toxic. α-CD and TRIMEB exhibited greater cytotoxicity in the Dulbecco's modified Eagle's medium than in heat-inactivated human serum indicating protective properties of the human serum. The predicted dynamic toxicity profiles (Td) for α-CD and TRIMEB indicated higher cytotoxicity for these cyclodextrins compared to the reference compound (dimethylsulfoxide). Molecular dynamics simulation of cholesterol binding to the CDs suggested that not just cholesterol but phospholipids extraction might be involved in the cytotoxicity. Overall, the results demonstrate that HPβCD has the potential to be used as a candidate for drug delivery vector development and signify a correlation between the in vitro cytotoxic effect and cholesterol binding of cyclodextrins.

Oleic acid derivative of polyethylenimine-functionalized proliposomes for enhancing oral bioavailability of extract of Ginkgo biloba

The present systematic study focused to investigate the oleic acid derivative of branched polyethylenimine (bPEI-OA)-functionalized proliposomes for improving the oral delivery of extract of Ginkgo biloba (GbE). The GbE proliposomes were prepared by a spray drying method at varying ratios of egg yolk phosphatidylcholine and cholesterol, and the optimized formulation was tailored with bPEI-OA to obtain bPEI-OA-functionalized proliposomes. The formulations were characterized for particle size, zeta potential, and entrapment efficiency. The release of GbE from proliposomes exhibited a sustained release. And the release rate was regulated by changing the amount of bPEI-OA on the proliposomes. The physical state characterization studies showed some interactions between GbE and other materials, such as hydrogen bonds and van der Waals forces during the process of preparation of proliposomes. The in situ single-pass perfusion and oral bioavailability studies were performed in rats. The significant increase in absorption constant (Ka) and apparent permeability coefficient (Papp) from bPEI-OA-functionalized proliposomes indicated the importance of positive charge for effective uptake across the gastrointestinal tract. The oral bioavailability of bPEI-OA-functionalized proliposomes was remarkable enhanced in comparison with control and conventional proliposomes. The bPEI-OA-functionalized proliposomes showed great potential of improving oral absorption of GbE as a suitable carrier.