Solid Dispersion System Research Articles

Characterization of Clove Oil Nanoparticles and Their Insecticidal Activity against Cryptolestes ferrugineus (Stephens) (Coleoptera: Laemophloeidae)

The application of essential oils to storage pest control requires an appropriate formulation formed by biodegradable compounds. This formulation should protect essential oils from degradation and evaporation while simultaneously allowing sustained release. This study aims to characterize nanoparticles loaded by clove essential oil-based polymer polyethylene glycol (PEG) and to investigate their insecticidal activity. In this study, clove oil solid dispersion was prepared using the fusion or melting-dispersion method with polyethylene glycol 6000 (PEG 6000) to form a binary solid dispersion system. The ratio of 10% of clove oil to PEG was optimal and had low PDI, small size, and the highest clove oil loading efficiency. Their size changed from 179 to 197 nm after 24 weeks of storage and the loading efficiency decreased for about 36%. Clove oil formulation in nanoparticles could not enhance the toxicity of clove oil but yet still showed high contact toxicity to C. ferrugineus. These formulations also have the slow and persistent release of the bioactive.

REVIEW: Increased Dissolution Rate Ofloxacin in Solid Dispersion Systems

REVIEW: Increased Dissolution Rate Ofloxacin in Solid Dispersion Systems

Preparation of solid dispersion systems for enhanced dissolution of poorly water soluble diacerein: In-vitro evaluation, optimization and physiologically based pharmacokinetic modeling

Diacerein (DCN), a BCS II compound, suffers from poor aqueous solubility and limited bioavailability. Solid dispersion systems (SD) of DCN were prepared by solvent evaporation, using hydrophilic polymers. In-vitro dissolution studies were performed and dissolution parameters were evaluated. I-Optimal factorial design was employed to study the effect of formulation variables (drug:polymer ratio and polymer type) on the measured responses including; drug content (DC) (%), dissolution efficiency at 15 min (DE (15 min)%) and 60 min (DE (60 min)%) and mean dissolution time (MDT) (min). The optimized SD was selected, prepared and evaluated, allowing 10.83 and 3.42 fold increase in DE (15 min)%, DE (60 min)%, respectively and 6.07 decrease in MDT, compared to plain drug. DSC, XRD analysis and SEM micrographs confirmed complete amorphization of DCN within the optimized SD. Physiologically based pharmacokinetic (PBPK) modeling was employed to predict PK parameters of DCN in middle aged healthy adults and geriatrics. Simcyp® software established in-vivo plasma concentration time curves of the optimized SD, compared to plain DCN. Relative bioavailability of the optimized SD compared to plain drug was 229.52% and 262.02% in healthy adults and geriatrics, respectively. Our study reports the utility of PBPK modeling for formulation development of BCS II APIs, via predicting their oral bio-performance.

Solid dispersion of quercetin-PVP K-30 and its effects on the antioxidant activity

Background: Quercetin (3,3’,4’,5,7-pentahydroxil-flavon) is a flavone and secondary metabolite known as flavonoid. Quercetin belongs to class II BCS that has low solubility and high permeability. The poor solubility of quercetin restricts the accessibility and bioavailability. Objectives: To increase the solubility, dissolution, and antioxidant activity in a solid dispersion system. Methods: Preparation of quersetin-PVP K-30 solid dispersion was conducted using the freeze-drying method at -96 degree C for 24 hours with a ratio of 1:1, 1:0.5, and 0.5:1 and a 1:1 physical mixture of quercetin-PVP K-30. The solid dispersion of quercetin-PVP K-30 was characterized by Scanning Electron Microscopy (SEM), X-Ray Diffraction (XRD) analysis, and FT-IR spectrophotometric analysis. Solubility test was analyzed using a UV-Vis spectrophotometer, dissolution test was done using a paddle-type dissolution tester, dissolved quercetin concentrations were analyzed using a UV-Vis spectrophotometer, and antioxidant activity was determined using the DPPH method in a UV-Vis spectrophotometer. Results: SEM analysis showed the formation of quercetin-PVP K-30 solid dispersion using the freeze-drying method, and the form changed into anhydrate as seen from the XRD results with the presence of new crystalline peaks in solid dispersion, which were not seen in pure quercetin and PVP K-30. Quercetin-PVP K-30 solid dispersion could increase the solubility by 54-fold at a ratio of 0.5:1 with 94.36%±0.85 quercetin dissolved in 120 minutes. The formation of this solid dispersion affected the antioxidant activity which was observable from the IC50 value at the best ratio of 0.5:1 reaching 0.714 microgram/mL while the IC50 value of pure quercetin is 1.102 microgram/mL. Conclusion: The formation of quercetin solid dispersion could increase the solubility and dissolution and affect the antioxidant activity. Keywords: solid dispersion, freeze-drying, quercetin, antioxidant

Development of orally disintegrating tablets containing solid dispersion of a poorly soluble drug for enhanced dissolution: In-vitro optimization/in-vivo evaluation.

Diacerein (DCN), a potent anti-inflammatory API used to treat osteoarthritis yet, it suffers from poor water solubility which affects its oral absorption. Unabsorbed colonic DCN is converted into rhein, which is responsible for laxation as a main side effect of DCN treatment. Therefore, in this study orally disintegrating tablets (ODTs) loaded with optimized DCN solid dispersion system were prepared using different co-processed excipients (Prosolv® ODT, Pharmaburst® 500 and F-melt®), aiming to achieve improved solubility, rapid absorption and consequently limited amount of rhein reaching the colon. Prepared ODTs were evaluated for physical characteristics, in-vitro drug release, disintegration and wetting times. Dissolution parameters; dissolution efficiency percent at 10 (DE (10 min)%) and 30 (DE (30 min)%) min and mean dissolution time (MDT) were determined. The optimized ODT showed 1.50 and 1.12 fold increase in DE (10 min)% and DE (30 min)%, respectively and 2 fold decrease in MDT, compared to Diacerein® capsules. In-vivo anti-inflammatory effect of optimized ODT, using rat paw edema revealed significant increase in edema inhibition (p < 0.0465) and promoted onset of action compared to Diacerein® capsules at 0.5 hr. It could be concluded that optimized ODT could be promising for enhanced dissolution and rapid absorption of DCN from the oral cavity.

Determination of the physical state of a drug in amorphous solid dispersions using artificial neural networks and ATR-FTIR spectroscopy

The objective of the present study was to evaluate the use of artificial neural networks (ANNs) in the development of a new chemometric model that will be able to simultaneously distinguish and quantify the percentage of the crystalline and the neat amorphous drug located within the drug-rich amorphous zones formed in an amorphous solid dispersion (ASD) system. Attenuated total reflectance Fourier-transform infrared (ATR-FTIR) spectroscopy was used, while Rivaroxaban (RIV, drug) and Soluplus® (SOL, matrix-carrier) were selected for the preparation of a suitable ASD model system. Adequate calibration and test sets were prepared by spiking different percentages of the crystalline and the amorphous drug in the ASDs (prepared by the melting - quench cooling approach), while a 24 full factorial experimental design was employed for the screening of ANN's structure and training parameters as well as spectra region selection and data preprocessing. Results showed increased prediction performance, measured based on the root mean squared error of prediction (RMSEp) for the test sample, for both the crystalline (RMSEp (crystal) = 0.86) and the amorphous (RMSEp (amorphous) = 2.14) drug. Comparison with traditional regression techniques, such as partial least square and principle component regressions, revealed the superiority of ANNs, indicating that in cases of high structural similarity between the investigated compounds (i.e., the crystalline and the amorphous forms of the same compound) the implementation of more powerful/sophisticated regression techniques, such as ANNs, is mandatory.

Application of HPMC HME polymer as hot melt extrusion carrier in carbamazepine solid dispersion

Aim This work is to investigate the application characteristics of a new hot melt extrusion (HME) polymer (HME-grade hydroxypropyl methylcellulose, namely HPMC HME 15LV) in solid dispersion by HME. Methods Carbamazepine (CBZ) was chosen as the model drug. And two types of solid dispersion system was prepared by HME, that is, single carrier system which was composed of PVP VA64(VA64) or Soluplus (SOL), and binary carrier which was composed of HPMC HME 15LV and SOL. Phase analysis of the extrudates were characterized by differential scanning calorimetry (DSC) and powder X-ray diffraction (PXRD). The dissolution, moisture absorption and thermal stability CBZ solid dispersion (CBZ-SD) were also investigated. In addition, the mechanism that affects the capsule dissolution was evaluated by the viscosity test and infiltration capability test. Results CBZ-SD was prepared by HME. DSC and PXRD results indicated that CBZ was amorphous in all solid dispersions. Unlike CBZ-SD powder with high dissolution, CBZ-SD capsules showed the variable gelatinization phenomenon during dissolution and different dissolution behaviors, which can be interpreted by the viscosity test and infiltration capacity test. Furthermore, compared with single carrier system, CBZ-SD made by binary carrier exhibited lower moisture absorption and better thermal stability, which is benefit to the long-term stability of CBZ-SD. Conclusion HPMC HME 15LV, as a new HME carrier, has certain advantages in producing well CBZ-SD preparation. Its low viscosity can prevent the gelatinization phenomenon during capsule dissolution, as well as suitable Tg and low hygroscopicity were also benefit to the stability of CBZ-SD.

Combining Co-Amorphous-Based Spray Drying with Inert Carriers to Achieve Improved Bioavailability and Excellent Downstream Manufacturability.

It is crucial to improve poorly water-soluble orally administered drugs through both preclinical and therapeutic drug discovery. A co-amorphous formulation consisting of two low molecular weight (MW) molecules offers a solubility/dissolubility advantage over its crystalline form by maintaining their amorphous status. Here, we report on a co-amorphous solid dispersion (SD) system that includes inert carriers (lactose monohydrate or microcrystalline cellulose) and co-amorphous sacubitril (SAC)-valsartan (VAL) using the spray drying process. The strong molecular interactions between drugs were the driving force for forming robust co-amorphous SDs. Our system provided the highest solubility with more than ~11.5- and 3.12-times solubility increases when compared with the physical mixtures. Co-amorphous lactose monohydrate (LM) SDs showed better bioavailability of APIs (~356.27.8% and 154.01% for the relative bioavailability of LBQ 657 and valsartan, respectively). Co-amorphous inert carrier SDs possessed an excellent compressibility for the production of a direct compression pharmaceutical product. In conclusion, these brand-new co-amorphous SDs could reduce the number of unit processes to produce a final pharmaceutical product for downstream manufacturability.

Enhancing the Solubility of Curcumin Using a Solid Dispersion System with Hydroxypropyl-β-Cyclodextrin Prepared by Grinding, Freeze-Drying, and Common Solvent Evaporation Methods.

Cyclodextrins (CDs) and their derivatives significantly increase drug solubility by forming drug/CD complexes known as solid dispersions (SDs), which consist of an inclusion complex (IC), where the drug is entrapped within the CD cavity, and a non-IC. Here, the SDs of curcumin (CUR) and hydroxypropyl-β-cyclodextrin (HPβCD) were prepared using the grinding, freeze-drying (FD), and common solvent evaporation (CSE) methods and were physicochemically characterized using solubility, powder X-ray diffraction, Fourier transform infrared, differential scanning calorimetry, and dissolution studies. The second or higher order complex of CUR-HPβCD indicated the co-existence of ICs and non-ICs known as the SD system. When comparing the soluble drug amount with CUR crystals, the solubility of SDs was enhanced by up to 299-, 180-, and 489-fold, corresponding to the ground mixtures (GMs), freeze-drying mixtures (FDs), and common solvent evaporation mixtures (CSEs), respectively. The total transformation into the amorphous phase of CUR was observed in GMs and in CSE12, CSE14, and CSE18. The drug was well dispersed within HPβCD in GMs and CSEs, suggesting the formation of hydrogen bonds between CUR and HPβCD, whereas the dispersed behavior of FDs was similar to that of physical mixtures. In SDs, the melting temperature of CUR was in an increased order of CUR in 1:2 ICs, CUR in 1:1 ICs, and CUR crystals. The dissolution rate of CUR was positively improved as the amount of HPβCD in SDs increased. The SD system consisting of CUR and HPβCD significantly increased the drug solubility compared to ICs.

Role of Polymer Excipients in the Kinetic Stabilization of Drug-Rich Nanoparticles.

Amorphous solid dispersions (ASDs) of crystallizable drugs and polymer excipients are attractive for enhancing the solubility and bioavailability of hydrophobic drug molecules. In this study, the solution behavior of poly(N-isopropylacrylamide-co-N,N-dimethylacrylamide) (PND) and poly(vinylpyrrolidone-co-vinylacetate) (PVPVA), as polymer excipients, and nilutamide (NLT), phenytoin (PHY), and itraconazole (ITN) as model drugs, were monitored by an in vitro dissolution assay, small-angle X-ray scattering (SAXS), dynamic light scattering (DLS), cryogenic transmission electron microscopy (cryo-TEM), and polarized optical microscopy (POM). High degrees of drug supersaturation were coincident with the formation of amorphous nanoparticles in each system. The difference in particle size and kinetic stability between PND and PVPVA systems suggest a difference in how the polymers interact with the drug-rich phase. A series of scenarios are proposed based on whether the polymer interacts more strongly with the drug-rich nanoparticles or with water. Understanding the contribution of drug-rich nanoparticles to achievable supersaturation and the effect of polymer excipients on these particles will inform the design of future solid dispersion systems through a better understanding of the polymer/drug solution relationship.

Water-Induced Phase Separation of Spray-Dried Amorphous Solid Dispersions.

Spray drying is widely used in the manufacturing of amorphous solid dispersion (ASD) systems due to its fast drying rate, enabling kinetic trapping of the drug in amorphous form. Spray-drying conditions, such as solvent composition, can have a profound impact on the properties of spray-dried dispersions. In this study, the phase behavior of spray-dried dispersions from methanol and methanol–water mixtures was assessed using ritonavir and copovidone [poly(vinylpyrrolidone-co-vinyl acetate) (PVPVA)] as dispersion components. The resultant ASDs were characterized using differential scanning calorimetry (DSC), fluorescence spectroscopy, X-ray photoelectron spectroscopy (XPS), as well as surface-normalized dissolution rate (SNDR) measurements. Quaternary phase diagrams were calculated using a four-component Flory–Huggins model. It was found that the addition of water to the solvent system can lead to phase separation during the spray-drying process. A 10:90 H2O/MeOH solvent system caused a minor extent of phase separation. Phase heterogeneity in the 50 and 75% drug loading ASDs prepared from this spray solvent can be detected using DSC but not with other techniques used. The 25% drug loading system did not show phase heterogeneity in solid-state characterization but exhibited a compromised dissolution rate compared to that of the miscible ASD prepared from H2O-free solvent. This is possibly due to the formation of slow-releasing drug-rich phases upon phase separation. ASDs prepared with a 60:40 H2O/MeOH solvent mixture showed phase heterogeneity with all analytical methods used. The surface composition of dispersion particles as measured by fluorescence spectroscopy and XPS showed good agreement, suggesting surface drug enrichment of the spray-dried ASD particles prepared from this solvent system. Calculated phase diagrams and drying trajectories were consistent with experimental observations, suggesting that small variations in solvent composition may cause significant changes in ASD phase behavior during drying. These findings should aid in spray-drying process development for ASD manufacturing and can be applied broadly to assess the risk of phase separation for spray-drying systems using mixed organic solvents or other solvent-based processes.

Quantification of atovaquone from amorphous solid dispersion formulation using HPLC: An in vitro and ex vivo investigation

Atovaquone (ATQ) is a poorly soluble drug. Therefore, formulating ATQ into its supersaturated state through solid dispersion for bioavailability enhancement can be of great value. However, due to fast crystallising properties of ATQ, the quantification of ATQ in a supersaturated solid dispersion system can be complicated. Therefore, in pursuit of accurate quantification of such sample, a simple HPLC analytical method utilising a C18 column (250 × 4.6 mm ID, 5 μm) for the quantitation of ATQ has been developed and validated. Atovaquone elution using the proposed method demonstrated a retention time around 7.6 min with good linearity (R2 > 0.999). The system suitability is also detailed with the tailing factor at 1.365 ± 0.002. The addition of solubilising agent as sample treatment step aided in ensuring the accurate quantitation of the fast crystallising ATQ. The developed HPLC quantitation method has been successfully employed in the analysis of ATQ from solid dispersion samples in in vitro dissolution as well as ex vivo permeation studies for formulation development.

Ginsenoside CK-loaded self-nanomicellizing solid dispersion with enhanced solubility and oral bioavailability

Ginsenoside compound K (CK) is a major ginsenoside metabolite of protopanaxadiol, which exhibits numerous pharmacological activity such as cardioprotective and antidiabetic. However, the therapeutic application of CK is hampered by its physicochemical characteristics and low oral bioavailability (BA). The present work aims at the preparation of CK to improve its dissolution and enhance the oral BA for the management of arrhythmia by using self-nanomicellizing solid dispersion system (SSD). The formulations were characterized by advanced techniques like DSC, XRD, FTIR, SEM and XRD. In the in vivo pharmacokinetic study, UPLC-MS/MS was used to measure the concentration of CK in plasma. Mapping Lab was applied in the experiment of perfused intact hearts to determine the ventricular rate and ventricular conduction velocity. The solubility of CK-SSD8 was 4658.11 ± 6.66 μg/ml, which is 130-fold than free CK, and the dissolution rate was faster than any other dosage forms. The average diameters of CK-SSD were smaller than 100 nm. The in vivo pharmacokinetic study revealed that the AUC(0-24) of CK-SSD8 formulation was 2.02-fold higher than pure CK. Moreover, the study performed to evaluate the efficiency in arrhythmia treatment showed a reduced ventricular rate and ventricular conduction velocity. Thus, CK-SSD could serve as potential carrier candidate in improving the clinical application of CK.

Solid Dispersions of Famotidine: Physicochemical Properties and In Vivo Comparative Study on the Inhibition of Hyperacidity

AbstractFamotidine is a potent histamine 2 antagonist used in the treatment of gastric acid overproduction. Famotidine belongs to Class IV in Biopharmaceutics Classification System (BCS) which has low solubility and membrane permeability. The purpose of this study was to compare the solubility and dissolution profile of solid dispersions (SDs) of famotidine with mannitol (SD‐MAN) and with hydroxypropyl methylcellulose (SD‐HPMC), and to comparatively study their in vivo effectiveness against hyperacidity. Famotidine SDs were prepared by cogrinding technique with the respective carriers in various ratios and grinding time. SDs with the best solubility underwent dissolution rate studies, solid‐state characterization, and in vivo efficacy evaluation. The in vivo evaluation was conducted in Sprague Dawley rats receiving famotidine formulations in the dose equivalent to 12 mg/kg of famotidine. The study found that the famotidine SDs could greatly improve the solubility of famotidine by 100.61 and 120.91% for SD‐MAN and SD‐HPMC, respectively. The solid‐state characterization revealed the decrease in crystallinity degree of famotidine solid dispersion systems. The comparative study on the in vivo efficacy of famotidine SDs showed that SD‐HPMC was significantly better than SD‐MAN. This study concludes that SDs can improve the solubility and in vivo effectiveness of famotidine in overproduction of gastric acid.

Piroxicam ternary solid dispersion system for improvement of dissolution (%) and in vitro anti-inflammation effects

The improvement of drug solubility is a challenging task in the pharmaceutical industry; moreover, drug stability is also important. This study was designed to improve the dissolution (%) and in vitro anti-inflammation effects of piroxicam (PRX) and maintain its stability using a ternary solid dispersion (SD) system. The solubilizer (poloxamer 407 [P407®]) and carrier (Aerosil®200) were selected based on solubility test and pre-dissolution test, respectively. The SD1 formulation (PRX: Aerosil®200: P407® = 1:1:3 wt ratio) improved the dissolution (%) by over 1.11-/1.17-/1.21-fold and 1.77-/2.26-/1.39-fold compared with commercial products, Feldene® and pure PRX, respectively, in pH 1.2/distilled water/pH 6.8 buffer for 60 min, respectively. The anti-inflammation study of SD1 observed similar or improved compared to that of Feldene®. In conclusion, the SD1 was developed with significantly enhanced dissolution (%) and stability for 12 months. Thus, the SD1 is expected to improve bioavailability and be effective in anti-inflammatory treatment in animal study.

Improvement in the Oral Bioavailability and Efficacy of New Ezetimibe Formulations-Comparative Study of a Solid Dispersion and Different Micellar Systems.

Ezetimibe (EZ) is a poorly water-soluble drug with low bioavailability. Strategies such as solid dispersions (SD) and micellar systems (MS) were developed to identify the most effective drug delivery formulations with the highest oral bioavailability, and to improve their lipid-lowering effect. The EZ formulations were prepared with different proportions of Kolliphor® RH40 as a surfactant (1:0.25, 1:0.5 and 1:0.75) and croscarmellose as a hydrophilic carrier. These excipients, and the addition of microcrystalline cellulose during the production process, led to significant improvements in the dissolution profiles of MS. Powder X-ray diffraction (PXRD), differential scanning calorimetry (DSC) and scanning electron microscopy (SEM) revealed an amorphous form of ezetimibe with different semicrystalline states of microcrystalline cellulose for MS-I (1:0.75) and MS-II (1:0.75). Pharmacokinetic analysis after administration of MS-II (1:0.75) demonstrated a 173.86% increase in maximum plasma concentration (Cmax) and a 142.99% increase in oral bioavailability compared to EZ raw material (EZ-RM). Efficacy studies with the micellar system MS-II (1:0.75) in rats with hyperlipidemia showed that total cholesterol, triglycerides and high-density lipoprotein were reduced to normal levels and revealed improvements in low-density lipoprotein, aspartate and alanine aminotransferase. The improvement in the dissolution rate with micellar systems increases bioavailability and enhances the anti-hyperlipidemic effect of EZ.

Chitin biomass-nifedipine amorphous solid dispersion for enhancement of hydrophobic drug dissolution in aqueous media

Solid dispersions of poorly-water soluble nifedipine using microparticles fabricated from chitin biomass were prepared to improve the drug dissolution in an aqueous medium. After the drug loading and solvent evaporation, the drug loading capacity of 1, 6, and 19 %w/w was obtained. In the microstructure, the drug was dispersed on the porous chitin carrier with minor agglomeration leading to reduced crystallization and improved dissolution, nearly 100%, as compared to the pure nifedipine powder and the physical mixture with chitin. There was an interaction between functional groups of the drug and polymer, consequently the release prolonged for the entire 6 h with the maximum drug solubility of about 300 μg/ml. An in vitro release study showed that nifedipine effectively released from chitin into a simulated gastric releasing medium (pH 1.2). In this case, the release mechanism was best fitted with a Zero-order model based on the Fick's Law in the first 2 h. This research indicated that employing microparticle obtained from chitin biomass in the solid dispersion system lowered the drug recrystallization, facilitated drug release, and provided the sustainability in pharmaceutical science.

Improving the dissolution of a water-insoluble orphan drug through a fused deposition modelling 3-Dimensional printing technology approach

Lennox-Gastaut Syndrome (LGS) is a rare form of childhood epilepsy. Rufinamide is an orphan drug indicated for the treatment of LGS. Three-Dimensional Printing (3DP) is a process in which solid objects are created based on a digital file by adding materials layer by layer. Fused deposition modelling (FDM) is a 3DP technique with the advantages of solid dispersion systems and the ability to use various pharmaceutical excipients in small scales, which makes this technology favorable for the production of orphan drugs. Rufinamide is a water-insoluble lipophilic compound which can exist in different polymorphic forms. The therapeutic dose is 3200 mg/day, at which rufinamide exhibits nonlinear pharmacokinetics, which may be attributed to its limited solubility. The main purpose of this paper is to improve the dissolution of rufinamide through the use of 3DP technology. For this purpose, optimum 3DP tablets were developed based on 3DP manufacturability and dissolution behaviors. The findings suggest that a mixture of hydroxypropyl methylcellulose (HPMC), Soluplus®, Kollidon® VA64, Gelucire® 48/16 and Triacetin are suitable excipients for FDM-3DP technology that can improve the dissolution of rufinamide. The optimum 3DP tablet shows significantly higher dissolution than Inovelon® at the therapeutic dose due to its improved wdissolution.

Solid dispersion systems engineered from hydroxypropyl‐β‐cyclodextrin and water‐soluble polymers for enhanced oral bioavailability of nimodipine

Nimodipine (NMD) is a calcium channel blocker that is used in the treatment of cerebrovascular disorders, such as stroke indicated for biological rhythm and neurological disorders. According to biopharmaceutical classification, NMD is categorized as a class ΙΙ drug, meaning it has a poor solubility profile. The objective of this experiment is to prepare multicomponent systems to enhance the solubility, dissolution, and bioavailability of NMD. Inclusion complex and solvent evaporation techniques have been exploited to overcome this challenge. in vitro dissolution studies and solubility, the profile was performed in three pH media (pH 7.5, 1.2, and 6.8). The drug release at (Q60min) for SD‐PVP3 was 33‐fold higher than pure NMD in double‐distilled water. The solubility of SD PVP3 was about 30 times higher than plain NMD in double‐distilled water. A pharmacokinetic study in rats indicated that the AUC0‐720 value of the inclusion complex (NMD‐KD) was 1.63‐fold higher than pure NMD. At the same time, the solid dispersion (NMD‐SD PVP3) was 3.94‐fold higher than that of plain NMD, indicating a significant increase in the bioavailability of NMD. The combination of the inclusion complex and solvent evaporation method led to the formation of new solid dispersions (SD PLX and SD PVP), which significantly increased the solubility, dissolution, and the oral bioavailability of NMD.

Design and Characterization of Phosphatidylcholine-Based Solid Dispersions of Aprepitant for Enhanced Solubility and Dissolution.

This study aimed to improve the solubility and dissolution of aprepitant, a drug with poor aqueous solubility, using a phosphatidylcholine (PC)-based solid dispersion system. When fabricating the PC-based solid dispersion, we employed mesoporous microparticles, as an adsorbent, and disintegrants to improve the sticky nature of PC and dissolution of aprepitant, respectively. The solid dispersions were prepared by a solvent evaporation technique and characterized by Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry, and X-ray powder diffraction. The FTIR results showed that aprepitant interacted with the PC carrier by both hydrogen bonds and van der Waals forces that can also be observed in the interaction between aprepitant and polymer carriers. The solid dispersions fabricated with only PC were not sufficient to convert the crystallinity of aprepitant to an amorphous state, whereas the formulations that included adsorbent and disintegrant successfully changed that of aprepitant to an amorphous state. Both the solubility and dissolution of aprepitant were considerably enhanced in the PC-based solid dispersions containing adsorbent and disintegrant compared with those of pure aprepitant and polymer-based solid dispersions. Therefore, these results suggest that our PC-based solid dispersion system is a promising alternative to conventional formulations for poorly water-soluble drugs, such as aprepitant.