Inclusion complex of methyl-β-cyclodextrin and olanzapine as potential drug delivery system for schizophrenia

NMR analysis, cytotoxic activity and theoretical study of a complex between SRPIN340 and p-sulfonic acid calix[6]arene

Aim: This study aimed to enhance the aqueous dissolution of SRPK inhibitor N-(2-(piperidin-1-yl)-5-(trifluoromethyl)phenyl)isonicotinamide (SRPIN340).Materials & Methods: A complex with p-sulfonic calix[6]arene (Host) and SRPIN340 (Guest) was prepared, studied via 1H nuclear magnetic resonance (NMR) and theoretical calculations and biologically evaluated on cancer cell lines.Results & conclusion: The 1:1 host (H)/guest (G) complex significantly enhanced the aqueous dissolution of SRPIN340, achieving 64.8% water solubility as determined by 1H NMR quantification analysis. The H/G complex reduced cell viability by 75% for HL60, ∼50% for Nalm6 and Jurkat, and ∼30% for B16F10 cells. It exhibited greater cytotoxicity than free SRPIN340 against Jurkat and B16F10 cells. Theoretical studies indicated hydrogen bond stabilization of the complex, suggesting broader applicability of SRPIN340 across diverse biological systems.

Solubilization of drugs using beta-cyclodextrin: Experimental data and modeling

Many drug candidates fail to complete the entire drug development process because of poor physicochemical properties. Solubility is an important physicochemical property which plays a vital role in various stages of drug discovery and development. Several methods have been proposed to enhance the solubility of drugs, and complex formation with cyclodextrins is among them. Beta-cyclodextrin (βCD) is a common excipient for solubilization of drugs. The aim of this study is to develop the mechanistic QSPR models to predict the solubility enhancement of a drug in the presence of βCD. In this study, the solubility enhancement of some drugs in the presence of 10mM βCD at 25°C was experimentally determined or collected from the literature. Two different models to predict the solubilization by βCD were developed by binary logistic regression using structural properties of drugs with more than 80% accuracy. Polar surface area and excess molar refraction are the main parameters for estimating solubilization by βCD. Moreover, other descriptors related to hydrophobicity and the capability of hydrogen bonding formation of molecules could improve the accuracy of the established models.

Orally fast dissolving α-lipoic acid electrospun nanofibers mitigates lipopolysaccharide induced inflammation in RAW 264.7 macrophages

α-Lipoic acid (LA), a dietary supplement known for its strong antioxidant and anti-inflammatory potential, faces challenges due to its poor aqueous solubility and thermal instability. To address these issues, herein methyl-beta-cyclodextrin (M-β-CD) was utilized to create inclusion complex (IC) of LA in 1:1 M stoichiometric ratio of M-β-CD to LA. The LA-M-β-CD-IC was further combined with pullulan (PUL), a non-toxic and water-soluble biopolymer, for the development of electrospun nanofibers (NF) by green and sustainable approach. The resulting PUL/LA/M-β-CD NF formed as a self-standing and flexible material with an average diameter of 569 ± 129 nm and encapsulation efficiency of ∼86.90 %. The developed NF demonstrated an accelerated release, quick dissolution, and disintegration when exposed to artificial saliva replicating the conditions of oral cavity. PUL/LA/M-β-CD NF attenuated the production of ROS and NO by downregulating pro-inflammatory enzymes (iNOS and COX-2) in lipopolysaccharide (LPS) stimulated RAW 264.7 cells. Moreover, PUL/LA/M-β-CD NF also significantly downregulated the expression of pro-inflammatory cytokines including TNF-α, IL-6, and IL-1β along with suppression of NF-ĸB nuclear translocation in comparison to LA (at 250 μM). In nutshell, PUL/LA/M-β-CD NF demonstrated great potential as a rapid disintegrating delivery system for oral anti-inflammatory treatment due to the enhanced physicochemical characteristics of LA.

Formulation and characterization of amiodarone-methyl-beta-cyclodextrin inclusion complexes: A molecular modelling perspective

This study aimed to develop immediate-release tablets containing amiodarone hydrochloride (AM). AM is a BCS class II compound, i.e., high permeable, and poorly soluble. The interactions between amiodarone and methyl-β-cyclodextrin were DFT-based, theoretically measured, supporting the complexation of AM with cyclodextrin by using methyl-β-cyclodextrin through a spray-drying process. Thus, increasing substantially the drug solubility to 93.31% and 87.14%, respectively. Solubility studies demonstrated the formation of the Drug-Methyl-β-cyclodextrin inclusion complex with 1:1 stoichiometry. The complex formation was characterized by SBET, XRD, DSC, SEM, FTIR, and 1H NMR. Complementing, immediate-release tablets containing the inclusion complex were developed by direct compression, and in vitro dissolution studies were performed in gastrointestinal fluids using USP Pharmacopeia standard dissolution rate testing equipment. The dissolution rate of immediate-release tablets was substantially higher than the pristine drug in all mediums evaluated. These results confirm the application of methyl-β-cyclodextrin as an effective excipient for incorporation in novel dosage forms to increase the solubility of poorly soluble drugs.

Formulation of Silymarin-β Cyclodextrin-TPGS Inclusion Complex: Physicochemical Characterization, Molecular Docking, and Cell Viability Assessment against Breast Cancer Cell Lines

Silymarin (SIL) is a poorly water-soluble flavonoid reported for different pharmacological properties. Its therapeutic applications are limited due to poor water solubility. In this study, the solubility of silymarin has been enhanced by preparing freeze-dried binary and ternary complexes using beta cyclodextrin (βCD) and d-α-tocopherol polyethylene glycol 1000 succinate (TPGS). The stoichiometry of the drug and the carrier was selected from the phase solubility study. The dissolution study was performed to assess the effect of complexation on the release pattern of SIL. The formation of inclusion complexes was confirmed by different physicochemical studies. Finally, a cell viability assay (MCF 7; breast cancer cell line) was performed to compare the activity with free SIL. The phase solubilization results revealed the formation of a stable complex (binary) with a stability constant and complexation efficiency (CE) value of 288 mol L-1 and 0.045%. The ternary sample depicted a significantly enhanced stability constant and CE value (890 mol L-1 and 0.14%). The release study results showed a marked increase in the release pattern after addition of βCD (alone) in the binary mixture (49.4 ± 3.1%) as well as inclusion complex (66.2 ± 3.2%) compared to free SIL (32.7 ± 1.85%). Furthermore, with the addition of TPGS in SIL-βCD (ternary), the SIL release was found to be significantly enhanced from the SIL ternary mixture (79.2 ± 2.13%) in 120 min. However, fast SIL release was achieved with 99.2 ± 1.7% in 45 min for the SIL ternary complex. IR and NMR spectral analysis results revealed the formation of a stable complex with no drug-polymer interaction. The formation of complexes was also confirmed by the molecular docking study (docking scores of 4.1 and -6.4 kcal/mol). The in vitro cell viability result showed a concentration-dependent activity. The IC50 value of the SIL ternary complex was found to be significantly lower than that of free SIL. The findings of the study concluded that the prepared SIL inclusion complex can be used as an alternative oral delivery system to enhance solubility, dissolution, and biological activity against the tested cancer cell line.

Modulation of Distribution and Diffusion through the Lipophilic Membrane with Cyclodextrins Exemplified by a Model Pyridinecarboxamide Derivative

The main aims of the study were to disclose the influence of the structure on the solubility, distribution and permeability of the parent substances, iproniazid (IPN), isoniazid (INZ) and isonicotinamide (iNCT), at 310.2 K and to evaluate how the presence of cyclodextrins (2-hydroxypropyl-β-cyclodextrin (HP-β-CD) and methylated β-cyclodextrin (M-β-CD)) affects the distribution behavior and diffusion properties of a model pyridinecarboxamide derivative, iproniazid (IPN). The following order of decreasing the distribution and permeability coefficients was estimated: IPN > INZ > iNAM. A slight reduction of the distribution coefficients in the 1-octanol/buffer pH 7.4 and n-hexane/buffer pH 7.4 systems (more pronounced in the first system) was revealed. The extremely weak IPN/cyclodextrins complexes were estimated from the distribution experiments: K_C(IPN/HP-β-CD) > K_C(IPN/M-β-CD). The permeability coefficients of IPN through the lipophilic membrane-the PermeaPad barrier-were also measured with and without cyclodextrins in buffer solution. Permeability of iproniazid was increased in the presence of M-β-CD and reduced by HP-β-CD.

Inclusion complex of ketoconazole and p-sulfonic acid calix[6]arene improves antileishmanial activity and selectivity against Leishmania amazonensis and Leishmania infantum

Many previous studies presented the effectiveness of ketoconazole (KTZ) against leishmaniasis. However, the bioavailability and therapeutic efficacy of free KTZ are limited due to its low aqueous solubility. In this study, an inclusion complex (IC6HKTZ) was prepared with p-sulfonic acid calix[6]arene (CX6SO₃H) to improve the solubility and efficacy of KTZ against Leishmania amazonensis and Leishmania infantum promastigotes. A linear increase in KTZ solubility as a function of CX6SO₃H concentration was verified using the phase-solubility diagram. The resulting diagram was classified as A_L-type and a 1:1 host-guest stoichiometry was assumed to prepare IC6HKTZ by freeze-drying. FTIR, TG/DSC, XRD, and solid-state ¹³C NMR spectroscopy analyses were performed to confirm the formation of IC6HKTZ. The solubility enhancement of KTZ by 120.00 μM CX6SO₃H was about 95 times. The IC₅₀ values of IC6HKTZ and free KTZ were 3.95 and 14.35 μM for Leishmania amazonensis and 6.74 and 17.47 μM for Leishmania infantum, respectively. The viability of DH82 macrophages was not affected by CX6SO₃H. These results show that CX6SO₃H is a new supramolecular carrier system that improves antileishmanial activities to KTZ for the treatment of cutaneous and visceral leishmaniasis.

Evaluation of β-lapachone-methyl-β-cyclodextrin inclusion complex prepared by spray drying and its application against different developmental stages of Schistosoma mansoni in murine model

BACKGROUND

β-lapachone (β-lap) is a naphthoquinone widely found in species of vegetables. However, its poor aqueous solubility limits its systemic administration and clinical applications in vivo. To overcome this limitation, several studies have been carried out in order to investigate techniques that can enhance the solubility and dissolution rate of β-lap, such as the use of inclusion complexes with cyclodextrin.

PURPOSE

To evaluate the in vivo effect of β-lap complexed in methyl-β-cyclodextrin (MβCD) on the evolutionary stages of Schistosoma mansoni in a murine model.

METHODS

The development and characterization of the physicochemical properties of the inclusion complex of β-lap in β-lap:MβCD was prepared by solubility and dissolution tests, FTIR, DSC, X-RD and SEM. The mice were infected and subsequently treated with β-lap:MβCD orally with 50 mg/kg/day and 100 mg/kg/day for 5 consecutive days, starting therapy on the 1^st (skin schistosomula), 14^th (pulmonary schistosomula), 28^th (young worms) and 45^th (adult worms) days after infection. Control groups were also formed; one infected untreated, treated with MβCD, and the other treated with PZQ.

RESULTS

The loss of the crystalline form of β-lap in the β-lap:MβCD complex obtained by spray drying was proven through physical-chemical characterization analyses. β-lap:MβCD caused reduction in the number of worms of the 33.56%, 35.7%, 35.45% and 36.45%, when the dose was at 50 mg/kg, and 65.00%, 60.34%, 52.72% and 65.01%, in the dose 100 mg/kg; when treatment was started in the 1^st, 14^th, 28^th and 45^th days after infection, respectively. It was also possible to observe a significant reduction in the number of immature eggs and an increase in the number of ripe and dead eggs and, consequently, a reduction in the damage caused by the egg antigens to the host tissue, where we attributed the reduction in the average diameter of the granulomas to the β-lap.

CONCLUSION

The dissolved content of β-lap:MβCD by spray drying reached almost 100%, serving for future formulations and delineation of the mechanisms of action of β-lap against S. mansoni.

SARS-CoV-2 main protease (3CLpro) interaction with acyclovir antiviral drug/methyl-β-cyclodextrin complex: Physiochemical characterization and molecular docking

During the current outbreak of the novel coronavirus disease 2019 (COVID-19), researchers have examined several antiviral drugs with the potential to inhibit the proliferation of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The antiviral drug acyclovir (AVR), which is used to treat COVID-19, in complex with methyl-β-cyclodextrin (Mβ-CD) was examined in the solution and solid phases. UV-visible and fluorescence spectroscopic analyses confirmed that the guest (AVR) was included inside the host (Mβ-CD) cavity. A solid inclusion complex of AVR was prepared by co-precipitation, physical mixing, kneading, and bath sonication methods at a 1:1 ratio of Mβ-CD:AVR. The prepared Mβ-CD:AVR inclusion complex was characterized using Fourier transform infrared spectroscopy (FTIR), X-ray powder diffraction (XRD), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), and scanning electron microscopy (SEM) analysis. Phase solubility studies indicated the Mβ-CD:AVR inclusion complex exhibited a higher stability constant and linear enhancement in AVR solubility with increasing Mβ-CD concentrations. In silico analysis of the Mβ-CD/AVR inclusion complex confirmed that AVR drugs show potential as inhibitors of SARS-CoV-2 3C-like protease (3CL^pro) receptors. Results obtained using the PatchDock and FireDock servers indicated that the most favorable docking ligand was Mβ-CD:AVR, which interacted with SARS-CoV-2 (3CL^Pro) protease inhibitors with high geometric shape complementarity scores (2522 and 5872) and atomic contact energy (-313.77 and -214.70 kcal mol^-1). Our results suggest that the Mβ-CD/AVR inclusion complex inhibits the main protease of SARS-CoV-2, although further wet-lab experiments are needed to verify these findings.

Polyvinylpyrrolidone K-30-Based Crosslinked Fast Swelling Nanogels: An Impeccable Approach for Drug's Solubility Improvement

Poor solubility is a global issue of copious pharmaceutical industries as large number of drugs in development stage as well as already marketed products are poorly soluble which results in low dissolution and ultimately dosage increase. Current study is aimed at developing a polyvinylpyrrolidone- (PVP-K30-) based nanogel delivery system for solubility enhancement of poorly soluble drug olanzapine (OLP), as solubilization enhancement is the most noteworthy application of nanosystems. Crosslinking polymerization with subsequent condensation technique was used for the synthesis of nanogels, a highly responsive polymeric networks in drug's solubility. Developed nanogels were characterized by percent entrapment efficiency, sol-gel, percent swelling, percent drug loaded content (%DLC), percent porosity, stability, solubility, in vitro dissolution studies, FTIR, XRD, and SEM analysis. Furthermore, cytotoxicity study was conducted on rabbits to check the biocompatibility of the system. Particle size of nanogels was found with 178.99 ± 15.32 nm, and in vitro dissolution study exhibited that drug release properties were considerably enhanced as compared to the marketed formulation OLANZIA. The solubility studies indicated that solubility of OLP was noticeably improved up to 36.7-fold in phosphate buffer of pH 6.8. In vivo cytotoxicity study indicated that prepared PVP-K30-based formulation was biocompatible. On the basis of results obtained, the developed PVP-K30-co-poly (AMPS) nanogel delivery system is expected to be safe, effective, and cost-effective for solubility improvement of poorly soluble drugs.

Losartan Interactions with 2-Hydroxypropyl-β-CD

Losartan potassium salt (LSR) is a well-known antihypertensive drug with proven beneficial effects on human health. Its formulation with the non-toxic 2-hydroxypropyl-β-cyclodextrin (2-HP-β-CD) could improve its pharmacological profile. Thus, its molecular interactions are studied using a combination of Differential Scanning Calorimetry (DSC), Nuclear Magnetic Resonance (NMR) and Molecular Dynamics (MD). First, its complexation is shown through Differential Scanning Calorimetry as lyophilization provided distinct thermal properties in comparison to the mixture. The complexation is further proved by utilizing the chemical shift changes in the complexation and T1 values. Furthermore, the reversible favorable complexation was shown by MD calculations. Such physical chemical properties provide evidence that this formulation must be further explored through biological experiments.

Formulation of Genistein-HP β Cyclodextrin-Poloxamer 188 Ternary Inclusion Complex: Solubility to Cytotoxicity Assessment

The current study was designed to prepare the inclusion complex Genistein (GS) using Hydroxypropyl β cyclodextrin (HP β CD) and poloxamer 188 (PL 188). The binary inclusion complex (GS BC) and ternary inclusion complex (GS TC) were developed by microwave irradiation technique and evaluated for a comparative dissolution study. Further, the samples were assessed for FTIR, DSC, XRD, and NMR for the confirmation of complex formation. Finally, antioxidant and antimicrobial studies and cytotoxicity studies on a breast cancer (MCF-7) cell line were conducted. The dissolution study result showed a marked increment in GS dissolution/release after incorporation in binary (GS: HP β CD, 1:1) and ternary (GS: HP β CD: PL 188; 1:1:0.5) inclusion complexes. Moreover, the ternary complex exhibited a significant enhancement (p < 0.05) in dissolution than did the binary complexes. This might be due to the presence of PL 188, which helps in solubility enhancement of GS. DSC, XRD and SEM evaluation confirmed the modification in the structure of GS. FTIR and NMR results indicated the formation of an inclusion complex. The antioxidant and antimicrobial activity results revealed that GS TC has shown significant (p < 0.05) higher activity than pure GS. The cytotoxicity study results also depicted concentration-dependent cytotoxicity. GS TC exhibited significantly (p < 0.05) high cytotoxicity to cancer cells (IC₅₀ = 225 µg/mL) than pure GS (IC₅₀ = 480 µg/mL). Finally, it was concluded that a remarkable enhancement in the dissolution was observed after the inclusion of GS in the ternary complex and it therefore has significant potential for the treatment of breast cancer.

Difluprednate-Hydroxypropyl-β-Cyclodextrin-Based Ophthalmic Solution for Improved Delivery in a Porcine Eye Model

Purpose: Difluprednate (DFP) is an approved corticosteroid, available as an ophthalmic emulsion (Durezol^®), used to treat pain and inflammation of the eye following ocular surgeries. This study utilized hydroxypropyl-β-cyclodextrin (HPBCD)-based DFP ophthalmic solution for improved ocular delivery. Methods: The DFP-HPBCD complex formation was studied in the liquid and solid states. Phase solubility, molecular docking studies, differential scanning calorimetry, and Fourier transform infrared spectroscopy suggested inclusion complexation of DFP and HPBCD. Results: DFP-HPBCD-based eye drops (solution) provided 16 and 26 times higher transcorneal permeation when compared to the suspension (no HPBCD, control) and Durezol, respectively (P < 0.001). In addition, ocular drug distribution studies conducted in continuously perfused whole porcine eyes showed DFP permeated into all of the ocular tissues in significantly higher amounts than Durezol. Conclusions: The solution-based eye drops in this study is iso-osmotic, safe, and more permeable in porcine eyes compared to Durezol.

Applications of innovative technologies to the delivery of antipsychotics

Psychosis is a high-incidence pathology associated with a profound alteration in the perception of reality. The limitations of drugs available on the market have stimulated the search for alternative solutions to achieve effective antipsychotic therapies. In this review, we evaluate innovative formulations of antipsychotic drugs developed through the application of modern pharmaceutical technologies, including classes of micro and nanocarriers, such as lipid formulations, polymeric nanoparticles (NPs), solid dispersions, and cyclodextrins (CDs). We also consider alternative routes of administration to the oral and parenteral ones currently used. Improved solubility, stability of preparations, and pharmacokinetic (PK) and pharmacodynamic (PD) parameters confirm the potential of these new formulations in the treatment of psychotic disorders.

3D printing of immediate-release tablets containing olanzapine by filaments extrusion

In this work, hot-melt extrusion (HME) is coupled with fused deposition modeling (FDM) mediated 3D printing to demonstrate additive manufacturing to fabricate immediate release (IR) prototypes of olanzapine with the aim of enhanced solubility using a fast disintegrating polymer (Kollicoat^® IR). Drug-polymer solubility and interaction parameters were estimated by Hansen solubility parameters and Hildebrand-Scott equation. The obtained values signified drug-polymer miscibility. The detailed in vitro physicochemical evaluations of the developed filament through HME and its derived 3D printed tablet by FDM technique were assessed thoroughly by several analytical means such as light microscopy, DSC, XRD, FT-IR, SEM, etc. The average disintegration time of this developed 3D printed IR tablet was found to be 63.33 (±3.6) sec complying with the USP limit. Additionally, in vitro dissolution study data revealed almost close correlations and both showed 100% of drug release within 15 min, thus complying with the definition of IR tablet. Thus, this study demonstrates the feasibility of directly using olanzapine-Kollicoat^® IR through the HME process without the addition of any plasticizers, organic solvents, etc. and coupling of HME with 3D printing technology allowing prototypes of IR tablet of olanzapine.

Nano Carrier Drug Delivery Systems for the Treatment of Neuropsychiatric Disorders: Advantages and Limitations

Neuropsychiatric diseases are one of the main causes of disability, affecting millions of people. Various drugs are used for its treatment, although no effective therapy has been found yet. The blood brain barrier (BBB) significantly complicates drugs delivery to the target cells in the brain tissues. One of the problem-solving methods is the usage of nanocontainer systems. In this review we summarized the data about nanoparticles drug delivery systems and their application for the treatment of neuropsychiatric disorders. Firstly, we described and characterized types of nanocarriers: inorganic nanoparticles, polymeric and lipid nanocarriers, their advantages and disadvantages. We discussed ways to interact with nerve tissue and methods of BBB penetration. We provided a summary of nanotechnology-based pharmacotherapy of schizophrenia, bipolar disorder, depression, anxiety disorder and Alzheimer's disease, where development of nanocontainer drugs derives the most active. We described various experimental drugs for the treatment of Alzheimer's disease that include vector nanocontainers targeted on β-amyloid or tau-protein. Integrally, nanoparticles can substantially improve the drug delivery as its implication can increase BBB permeability, the pharmacodynamics and bioavailability of applied drugs. Thus, nanotechnology is anticipated to overcome the limitations of existing pharmacotherapy of psychiatric disorders and to effectively combine various treatment modalities in that direction.

Formulation of Piperine Ternary Inclusion Complex Using β CD and HPMC: Physicochemical Characterization, Molecular Docking, and Antimicrobial Testing

The present study was designed to evaluate the effect of hydroxyl propyl methyl cellulose (HPMC) on the complexation efficiency and dissolution of piperine (PPR) and β cyclodextrin (β CD) complex. The binary and ternary inclusion complexes were prepared using solvent evaporation and microwave irradiation methods. The samples were further evaluated for physicochemical evaluation, morphology, antimicrobial, and antioxidant activities. The binary and ternary samples showed high stability constant (Ks) value and complexation efficiency (CE). The dissolution study results revealed marked enhancement in the release of the binary inclusion complex and ternary inclusion complex compared to pure PPR. Fourier transform infrared (FTIR), nuclear magnetic resonance (NMR), and molecular docking results confirm the complex formation. X-ray powder diffractometry (XRD) and scanning electron microscopy (SEM) data revealed modification in the structure of PPR. 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging and antimicrobial results showed enhanced activity in the PPR complex in comparison to pure PPR. In conclusion, a remarkable enhancement in dissolution, antioxidant and antimicrobial activities were attained due to marked improvement in solubility through complexation of PPR with HPMC/β CD.

Formulation and Evaluation of Supramolecular Food-Grade Piperine HP β CD and TPGS Complex: Dissolution, Physicochemical Characterization, Molecular Docking, In Vitro Antioxidant Activity, and Antimicrobial Assessment

The purpose of the present study was to improve the aqueous solubility, dissolution, and antioxidant activity of the water-insoluble drug piperine (PIP). The study was performed by preparing PIP binary inclusion complex (PIP BIC) and piperine ternary inclusion complex (PIP TIC) by different methods. The effect of a hydrophilic auxiliary substance (TPGS) was assessed with addition to PIP and hydroxypropyl beta cyclodextrin (HP β CD) complex. The phase solubility study was performed to evaluate the complexation efficiency and stability constant. The aqueous solubility, dissolution, physicochemical assessment, antioxidant activity, antimicrobial activity, and molecular docking were further evaluated to check the effect of the complexation of PIP. The stability constant (Ks) value was found to be 238 and 461 M⁻¹ for the binary and ternary inclusion complex. The dissolution study results showed a marked enhancement of release in comparison to pure drug. XRD and SEM studies revealed the presence of more agglomerated and amorphous structures of PIP, which confirmed the formation of complexes. The results of DPPH radical scavenging and antimicrobial activity showed a significant (p < 0.05) enhancement in scavenging activity for PIP TIC (microwave irradiation (MI)). The docking studies have revealed that the binding affinity of TPGS at the PIP-HP β CD complex was −5.2 kcal/mol.

Preparation and in vitro characterization of rosuvastatin calcium incorporated methyl beta cyclodextrin and Captisol® inclusion complexes

Despite being the most effective hypolipidemic agent, poor physicochemical properties of Rosuvastatin calcium (RCa) remain challenging obstacles in the development of pharmaceutical dosage forms. Inclusion complexes (ICs) of RCa with cyclodextrin (CD) derivatives; methyl-beta-cyclodextrin (M-β-CD) and sulfobutylether-beta-cyclodextrin (SBE-β-CD; Captisol^®) were formulated by kneading and freeze-drying (lyophilization) methods. Pysicochemical properties of ICs were evaluated by SEM, DSC, XRD, FT-IR, ¹H-NMR analyses. Entrapment efficiency (EE), water solubility, in vitro release analyses were also performed. Safety and efficacy of the ICs were analyzed by cytotoxicity and permeation studies on Caco-2 cell lines. Both CDs indicated A_L type phase solubility diagrams showing that [1:1] molar ratio. Apparent stability constants (K_1:1) were found to be 60.93 M^-1 for M-β-CD and 158.07 M^-1 for Captisol^®. High EE in the range of 93.50-105.40% was achieved. Molar solubility of RCa was increased 3.7- and 4.1-fold with M-β-CD and Captisol^® ICs, respectively. In vitro release analyses have indicated the equivalence of dissolution profiles for M-β-CD and Captisol^® based ICs to that of pure RCa (f₂ > 50). Cytotoxicity studies on Caco-2 cell lines have revealed the safety of ICs for oral use. Permeability studies demonstrated that selected lyophilized F6 formulation has shown the best permeation rate with P_app value of 3.08 × 10^-7 cm·s^-1. Considering greater water solubility, lower toxicity, high efficiency of complexation as well as, RCa-like permeability and in vitro release behavior at pH 6.8; Captisol^® based lyophilized F6 formulation was selected as the best IC to be used in oral dosage forms of RCa.

Analytical techniques to recognize inclusion complexes formation involving monoterpenes and cyclodextrins: A study case with (-) borneol, a food ingredient

Monoterpenes are non-polar secondary metabolites widely used by industry due to their excellent therapeutic, food-ingredient and cosmetic properties. However, their low solubility in water limits their use. In this sense, cyclodextrins (CDs) have been widely used to solve these technological challenges. Thus, this study aims to use (-)-borneol as a monoterpene model to prepare inclusion complexes between β-CD and hydroxypropyl-β-CD (HP-β-CD) through different ways and characterize them in order to choose the best inclusion method to improve physicochemical properties of monoterpenes. To achieve this goal, the samples were prepared by physical mixture (PM), paste complex (PA) and freeze-drying complex (FD) and then, extensively characterized by thermal analysis, Fourier-transform infrared spectroscopy, scanning electron microscopy, size particle, X-ray diffraction and nuclear magnetic resonance. The physicochemical results showed that freeze-drying was more effective to form inclusion complexes between (-)-borneol with both CDs. This research highlights the importance of recognizing the best method to prepare inclusion complexes, including food additives as (-)-borneol, to achieve better results in food preparations.

Voltammetric/UV-Vis study of temozolomide inclusion complexes with cyclodextrin derivatives

Temozolomide (TMZ) - a chemotherapeutic agent possessing cytotoxic activity is used in single or combined therapies of human glioma. Difficulties in these applications, connected with low solubility and stability of temozolomide lead us to study the inclusion complexes between TMZ, and three cyclodextrins: β-cyclodextrin (βCD), monodeoxy-6-monoamino-β-cyclodextrin hydrochloride (βCDamine), and β-cyclodextrin containing galactosamine and triazole ring in the side group (βCDgal). The voltammetric and spectroscopy studies showed the improvement of the drug solubility and formation of stable complexes. Higuchi and Connors method was used to determine the solubilities of the drug in the presence of the selected cyclodextrins. Phase solubility diagrams showed increase of TMZ solubility and 1:1 stoichiometry of the complexes formed. The stability constant of TMZ- βCDgal complex was pH - dependent, larger at pH 7.4 (corresponding to the pH of the body fluids), than at pH 5.5, characteristic for the cancer cells environment. βCDgal ligand was an effective complexing agent for TMZ due to additional strong proton-acceptor π-π interactions between the triazole ring of the cyclodextrin and the ring of TMZ. The increased solubility and sustainability of TMZ complexes with βCDgal allow to propose this cyclodextrin as a promising TMZ carrier for further studies in the biological cell environment.

Poloxamer-407-Co-Poly (2-Acrylamido-2-Methylpropane Sulfonic Acid) Cross-linked Nanogels for Solubility Enhancement of Olanzapine: Synthesis, Characterization, and Toxicity Evaluation

Current study is focused to enhance the solubility of poorly soluble drug olanzapine (OLZ) by nanogels drug delivery system, as improved solubility is one of the most important applications of nanosystems. Poor solubility is a major issue, and 40% of marketed and about 75% of new active pharmaceutical ingredients are poorly water soluble which significantly affect the bioavailability and therapeutic effects of these drugs. In this study, nanogels, a promising system for solubility enhancement, were developed by free-radical polymerization technique. Different formulations were synthesized in which poloxamer-407 was cross-linked with 2-acrylamido-2-methylpropane sulfonic acid (AMPS) with the help of cross-linker methylene bisacrylamide (MBA). The chemically cross-linked nanogels were characterized by Fourier transform infrared spectroscopy (FT-IR), thermos gravimetric analysis (TGA), differential scanning calorimetry (DSC), X-ray diffraction (XRD), scanning electron microscopy (SEM), zeta size, swelling, sol-gel analysis, drug loading, solubility, and in vitro drug release studies. In order to determine the biocompatibility and cytotoxicity of nanogels to biological system, toxicity study on rabbits was also carried out. It was confirmed that the developed nanogels was thermally stable, safe, effective, and compatible to biological system, and the solubility of olanzapine (OLZ) was enhanced up to 38 folds as compared with reference product.

Dicarboxylic acid as a linker to improve the content of amorphous drug in drug-in-polymer film: Effects of molecular mobility, electrical conductivity and intermolecular interactions

Amorphous solid dispersion (ASD) is a well-established approach to improve the dissolution rate of the drugs with low water solubility. However, the application of the ASD was hindered by the low drug content and high risk of re-crystallization of drugs. The purpose of this research was to develop an ASD film with high content of amorphous olanzapine (OLN) for oral delivery. To overcome the high crystallization tendency of OLN in polyvinyl alcohol (PVA) films, three dicarboxylic acids (succinic acid (Suc), fumaric acid (Fum) and malic acid (Mal)) were introduced in the drug-in-polymer system as linkers between the drug and the polymer. The influence of the linkers on the re-crystallization of OLN in PVA films was evaluated by polarized light microscopy (PLM) and x-ray diffraction (XRD). Then, the possible mechanisms of crystallization inhibition were discussed based on the results of dielectric spectroscopy (DES), differential scanning calorimetry (DSC), attenuated total reflectance Fourier transform infrared (ATR-FTIR), Raman spectroscopy and molecular modeling. Finally, the effect of the linkers on the in vitro dissolution of the OLN-in-PVA films was studied in simulant saliva, and the in vivo performance of the optimal formulation was evaluated in rats. The results showed that OLN-in-PVA film have lower molecular mobility, lower electrical conductivity and stronger intermolecular interactions with the existence of Mal, which led to a better crystallization inhibition of OLN in PVA films. The re-crystallization of OLN in PVA films decreased the dissolution rate of OLN in simulant saliva. The in vivo performance of the optimal formulation was similar with that of OLN solution in rats. This study introduced a novel strategy to reduce the risk of drug re-crystallization in ASD, and also provided a deeper insight into the mechanisms of crystallization inhibition in ASD. The results will improve the judicious selection of excipients in pharmaceutical formulations.

Construction of a water-soluble and photostable rubropunctatin/β-cyclodextrin drug carrier

The purpose of the current study was to construct a β-cyclodextrin drug carrier for rubropunctatin to improve its water solubility and light stability for future cytotoxicity studies. The inclusion complexation behavior of rubropunctatin with β-cyclodextrin was investigated using FESEM, FT-IR and XRD. A molecular docking study was performed to elucidate the most probable inclusion structure. The inclusion complex could be completely dispersed in water and had a small size of 121.87 ± 2.13 nm (n = 3), a good PDI (0.320 ± 0.017), and an acceptable potential value of -27.7 ± 0.32 mV (n = 3). Furthermore, the stability of the rubropunctatin in water under light irradiation was found to be greatly enhanced after being encapsulated in cyclodextrin, and it exhibited a retention rate of over 70% vs. 10.17%. In addition, the cytotoxicity of the inclusion complex was evaluated by MTT assay and Annexin V-FITC/PI detection using cervical adenocarcinoma HeLa cells. The results showed that the inclusion complex had comparable toxicity compared to rubropunctatin solubilized with 0.4% DMSO. More importantly, the formation of the inclusion complex contributed greatly to the intensification of the bioavailability of rubropunctatin because the use of organic solvent was avoided.

Evaluation of antioxidant potencial of novel CaAl and NiAl layered double hydroxides loaded with olanzapine

Olanzapine (OLZ), is used in the treatment of bipolar disorder and schizophrenia, diseases that present oxidative stress in their physiopathology. It has low aqueous solubility, which may lead to low oral bioavailability. The search of new drug delivery systems (DDSs) that may increase dissolution rate of OLZ, associated with the investigation of the antioxidant potential of the loaded-systems become of major importance to understand improvement in bipolar disorder and schizophrenia therapy. Thus, this study aimed to evaluate the in vitro antioxidant potential of two different Layered Double Hydroxides (LDH) loaded with 5% of OLZ (CaAl and NiAl), by radical scavenging activity (2,2-Diphenyl-1-picrylhydrazyl and nitric oxid); radical cation scavenging activity (2,2'-azino-bis3-ethylbenzthiazoline-6-sulfonic acid ABTS) and evaluation of inhibition capacity of lipid peroxidation by thiobarbituric acid (TBARS). The results showed that both obtained LDH systems presented in vitro antioxidant capacity when associated with OLZ in all methods performed, and this activity is more pronounced with the systems containing OLZ compared to pure drug. The systems with CaAl was shown to have increased antioxidant potential, compared to NiAl, increasing the antioxidant activity up to 40,83%, 15,84% and 16,73%, as showed by the DPPH, nitric oxide and TBARS tests, respectively. The results revealed that the use of LDHs as a functional excipient may be promising in the pharmaceutical industry for bipolar disorder and schizophrenia therapy.

Methyl-β-cyclodextrin Inclusion Complex with β-Caryophyllene: Preparation, Characterization, and Improvement of Pharmacological Activities

β-Caryophyllene (BCP) is a sesquiterpene that shows high potential in pharmacological applications. However, these have been drastically limited by the respective volatility and poor water solubility. The present study investigates the formation of inclusion complexes between BCP and methyl-β-cyclodextrin (MβCD) and shows that these complexes promote a significant improvement of the anti-inflammatory, gastric protection, and antioxidant activities relative to neat BCP. It is shown that the solubility of BCP is significantly increased through complexation in phase solubility studies. Inclusion complexes with MβCD in solid state were prepared by three different methods, kneading, rotary evaporation, and lyophilization, with the latter confirmed by differential scanning calorimetry, Fourier transformed infrared spectroscopy, scanning electron microscopy, ¹H NMR spectroscopy, and molecular dynamics studies. This study provides for the first time a full characterization of inclusion complexes between BCP and MβCD and highlights the impact of complex formation upon pharmacological activity.

Applications of cyclodextrins in medical textiles - review

This paper presents data on the general properties and complexing ability of cyclodextrins and assessment methods (phase solubility, DSC tests and X-ray diffraction, FTIR spectra, analytical method). It focuses on the formation of drug deposits on the surface of a textile underlayer, using a cyclodextrin compound favoring the inclusion of a drug/active principle and its release onto the dermis of patients suffering from skin disorders, or for protection against insects. Moreover, it presents the kinetics, duration, diffusion flow and release media of the cyclodextrin drug for in vitro studies, as well as the release modeling of the active principle. The information focuses on therapies: antibacterial, anti-allergic, antifungal, chronic venous insufficiency, psoriasis and protection against insects. The pharmacodynamic agents/active ingredients used on cotton, woolen and synthetic textile fabrics are presented.

New Hybrid Nanomaterial Based on Self-Assembly of Cyclodextrins and Cobalt Prussian Blue Analogue Nanocubes

Supramolecular self-assembly has been demonstrated to be a useful approach to developing new functional nanomaterials. In this work, we used a cobalt Prussian blue analogue (PBA, Co3[Co(CN)6]2) compound and a β-cyclodextrin (CD) macrocycle to develop a novel host-guest PBA-CD nanomaterial. The preparation of the functional magnetic material involved the self-assembly of CD molecules onto a PBA surface by a co-precipitation method. According to transmission electronic microscopy results, PBA-CD exhibited a polydisperse structure composed of 3D nanocubes with a mean edge length of 85 nm, which became shorter after CD incorporation. The supramolecular arrangement and structural, crystalline and thermal properties of the hybrid material were studied in detail by vibrational and electronic spectroscopies and X-ray diffraction. The cyclic voltammogram of the hybrid material in a 0.1 mol · L(-1) NaCl supporting electrolyte exhibited a quasi-reversible redox process, attributed to Co2+/Co3+ conversion, with an E1/2 value of 0.46 V (vs. SCE), with higher reversibility observed for the system in the presence of CD. The standard rate constants for PBA and PBA-CD were determined to be 0.07 and 0.13 s(-1), respectively, which suggests that the interaction between the nanocubes and CD at the supramolecular level improves electron transfer. We expect that the properties observed for the hybrid material make it a potential candidate for (bio)sensing designs with a desirable capability for drug delivery.