Enhanced Dissolution Rate Research Articles

Enhancement of Solubility and Dissolution Rate of Poorly Soluble Anticancer Drug Using Nanostructured Lipid Carrier Based Drug Delivery System

Enhancement of Solubility and Dissolution Rate of Poorly Soluble Anticancer Drug Using Nanostructured Lipid Carrier Based Drug Delivery System

A novel cocrystal approach celecoxib with piperine: Simultaneously enhance dissolution rate and compressibility

Celecoxib, a selective COX-2 inhibitor non-steroidal anti-inflammatory drug (NSAID), exhibits analgesic and anti-inflammatory properties similar to piperine, the secondary metabolite of Piper nigrum L. Unfortunately, celecoxib has a low compressibility and low dissolution rate in aqueous medium. This study aimed to prepare a cocrystal of celecoxib and piperine to enhance the dissolution rate and compressibility properties of celecoxib. The cocrystal was synthesized using the seeding method and thoroughly characterized using Powder X-ray diffraction (XRD), differential scanning calorimetry (DSC), infrared spectrophotometry, and single-crystal X-ray diffraction techniques. The complete change in PXRD, decrease in melting point in DSC measurements, and shift in the NH stretching band in the FT-IR spectrum suggested the formation of cocrystals phase. Single-crystal XRD confirmed the formation of an equimolar ratio of cocrystals of celecoxib and piperine. The intrinsic dissolution test was conducted to confirm the impact on the cocrystal to dissolution, and it showed a slight increase compared to intact celecoxib. To assess the physico-mechanical properties, the cocrystal powders were compressed into tablets with varying forces. The results demonstrated a significant improvement in compressibility compared with intact celecoxib owing to the slip plane in the crystal lattice of the cocrystal. In conclusion, our novel celecoxib-piperine cocrystal exhibited distinct physicochemical characteristics compared to intact celecoxib, showing enhanced dissolution rate and compressibility.

Surface Solid Dispersion of Ketoconazole on Trehalose Dihydrate using Spray Drying to Achieve Enhanced Dissolution Rate.

Ketoconazole (K) is a poorly water-soluble drug that faces significant challenges in achieving therapeutic efficacy. This study aimed to enhance the dissolution rate of ketoconazole by depositing spray-dried ketoconazole (SK) onto the surface of ground trehalose dihydrate (T) using spray drying. Ketoconazole-trehalose surface solid dispersions (SKTs) were prepared in ratios of 1:1 (SK1T1), 1:4 (SK1T4), and 1:10 (SK1T10), and characterized them using particle size analysis, scanning electron microscopy, powder X-ray diffraction, and in vitro dissolution studies. Results showed that the dissolution rates of the dispersions were significantly higher than those of pure ketoconazole, with the 1:10 ratio showing the highest dissolution rate. The improved dissolution was attributed to the formation of a new crystalline phase and better dispersion of ketoconazole particles. These findings suggest that the surface solid dispersion approach could be a valuable method for enhancing the bioavailability of poorly water-soluble drugs.

Design and development of Fujicalin-based axitinib liquisolid compacts for improved dissolution and bioavailability to treat renal cell carcinoma

Poor dissolution of axitinib (AXT) limits its effectiveness through the oral route. The present study investigated, prospective of liquisolid (LS) technology to improve dissolution rate and oral bioavailability of AXT to treat renal cell carcinoma. LS compacts were fabricated with PEG 200, Fujicalin SG, and Aerosil 200 as solvent, carrier, and coat material, respectively. The behavior of LS-systems during tabletting was investigated using Kawakita, Heckel, and Leuenberger analysis. LS compacts were examined for P-XRD, DSC, SEM, and in vitro drug dissolution. For optimization, a 32 full factorial design was utilized. Cell line A498 was utilized for in vitro cytotoxicity study. A bioavailability study was performed using rabbits. DSC and P-XRD analysis confirmed the transition of crystalline AXT to its partial amorphization and molecular dispersion. Consequently, LS6 demonstrated a significantly rapid drug dissolution (Q20; >99 %) than the directly compressed tablets (18.05 %). Additionally, 2.03-fold increase in oral bioavailability, and inhibited dose-dependent cell growth with 1.75-fold increased apoptosis rate. Overall, an LS6 compact consisting of 15 % AXT concentration in PEG 200 and a 20 w/w ratio of Fujicalin SG: Aerosil 200 exhibited improved formulation properties, enhanced dissolution rate, and bioavailability. Thus developed potential product may contribute low-cost production with patient-improved survival expectations.

Biocompatibility and antimicrobial efficacy of silver-doped borosilicate bioactive glass for tissue engineering application

Borate bioactive glasses are an auspicious material for tissue engineering applications due to their enhanced dissolution rate, bioactivity, and capacity to integrate therapeutic ions. In this study, borate-based S49B4 bioactive glass doped with silver at mass fraction of 0.5, 1, and 3 wt% were studied for bioactivity, degradation, antibacterial, and cytocompatibility. Thermogravimetric analysis revealed that the bioactive glasses were thermally stable between 600 and 700 °C. Fourier transform infrared spectroscopy and X-ray diffraction confirmed the successful synthesis of an amorphous phase of the doped borosilicate bioactive glasses and the incorporation of silver ion crystals within the structure, as well as associated contributions from borate and silicate network formers in the borosilicate bioactive glass. Morphological evaluation revealed that the borosilicate bioactive glasses exhibit a uniform and spherical shape across all formulations, with the mean particle size varying from 65 to 76 nm. An in-vitro acellular bioactivity in simulated body fluid medium showed that increasing the silver content increased the degradation rate and pH. Besides, scanning electron microscopy and Energy dispersive X-ray spectroscopy analysis revealed an upsurge in apatite production on the BBGs' surfaces as well as incremental Calcium-Phosphate ratio values of 1.50, 1.65 and 1.70 as the silver content increases. The antibacterial effect was tested against Escherichia coli and Staphylococcus aureus, while cytocompatibility was tested against human gingival epithelial cells. Silver integration at 1 wt percent yielded the most promising outcomes, which were particularly bactericidal at 79.8 % for Escherichia coli and 93.41 % for Staphylococcus aureus. Similarly, its Lactate Dehydrogenase percentage is significantly similar to the negative control employed in the study, indicating its biocompatibility. In contrast, 3 wt% silver exhibited the maximum bactericidal activity while also exhibiting mild cytotoxicity. In summary, our research indicates that elevated silver concentration enhances the bioactivity and antimicrobial characteristics of borosilicate bioactive glasses; nevertheless, a higher silver weight percent in this study also increases the possibility of cytotoxicity. It is therefore essential to carefully regulate the amount of silver doping at lower concentrations in order to maximize antibacterial action and minimize toxicity to human cells. The results presented here contribute to our understanding of the prospective use of silver doped borosilicate bioactive glasses as a possible material for tissue engineering applications.

FORMULATION AND EVALUATION OF FLUTICASONE PROPIONATE-LOADED MICROEMULSION

This report focuses on the development of nanoemulsions, highlighting their potential as innovative drug delivery systems. The study, titled "Fluticasone Butyrate-Equipped Micelle Liposomal Delivery," aims to improve dissolution rates and bioactivity. The emulsifier structures showed a clear quantum fluid velocity, and in-vitro studies since 2005 revealed that certain formulations enhanced drug dissolution rates compared to others. This improved solubilization could extend bioactivity, as seen with atropine propionate. The study also examined the physicochemical properties, with results depending on the composition of surfactant, co-surfactant, water, and oil in the formulations. Process graphs indicated thicker emulsifier regions at the micellar margin, which led to improved formulations. Enhanced dissolution rates, particularly in oil-based drugs, were linked to the presence of nano-sized particles (54.30 nm) with a zeta potential of +/-10.61 mV. Stability tests confirmed that the solid dispersion remained stable for six months. Overall, this research supports the potential of nanoemulsions to improve drug delivery and efficacy.

Enhancement of Solubility and Dissolution Rate of Simvastatin Tablets by Liquisolid Compact Approach

The aim of the current work was to improve the solubility and dissolution rate of poorly water-soluble drug, simvastatin (SM) by using the liquisolid compact technique (LS; SM-LS). Liquid load factors, and excipient ratios were used to calculate the required amounts of excipients necessary to prepare the SM-LS and compressed to tablets according to mathematical models. Avicel PH102, Aerosil 200 and Crosspovidone (CP) was used as carrier, coating material and disintegrant, respectively. Drug-excipient mixtures were evaluated compatibility by Attenuated total reflectance (ATR) and differential scanning calorimetry (DSC). Prepared SM-LS formulations were evaluated for various pre-compression and post-compressional parameters, in-vitro dissolution, and stability studies (40 ± 2°C / 75 ± 5% RH) for 3 months. Among the different formulations, LS10 formulation which contains 30% drug, 5% CP, Avicel pH 102: Aerosil 200 (1:10) showed 14-folds increase in dissolution rate when compared with pure SM powder. FTIR-ATR and DSC studies confirmed that there was no interaction between the drug and excipients. Further, the LS10 formulation had shown comparable dissolution profile with commercially available tablet formulation. The LS10 formulation showed no significant changes in the physicochemical properties over 3 months during stability studies. Therefore, the SM loaded LS formulation could be considered as an alternative approach to enhance the solubility and dissolution for commercial formulations. Keywords: Liquisolids compacts, solubility, dissolution, carrier, coating material, stability.

CRYSTALLO-CO-AGGLOMERATION OF SIMVASTATIN: IMPROVING DISSOLUTION AND MICROMERITIC PROPERTIES

Simvastatin (SMV), a poorly soluble drug, faces challenges in pharmaceutical formulation due to its limited solubility and poor flow properties. This study aimed to enhance the physicochemical properties of SMV by preparing spherical crystals using a crystallo-co-agglomeration. Spherical crystals of SMV were prepared by dissolving the drug in methanol and adding it to an aqueous solution containing PVP K-30 and PEG 6000 under constant stirring. The resulting agglomerates were filtered, dried, and characterized using Fourier Transform Infrared (FTIR) spectroscopy, Powder X-Ray Diffraction (PXRD), Differential Scanning Calorimetry (DSC), Scanning Electron Microscopy (SEM), and dissolution testing. Micromeritic properties, including bulk density, Hausner ratio, compressibility index, angle of repose, and flowability, were also evaluated. FTIR confirmed the chemical integrity of SMV with minor shifts indicating interactions with stabilizers. PXRD and DSC analyses revealed reduced crystallinity and partial amorphization in the spherical crystals. SEM showed spherical morphology. Dissolution testing demonstrated a significantly enhanced dissolution rate for the spherical crystals compared to pure SMV. Improved micromeritic properties were also observed, indicating better flowability and packing density. Spherical crystallization significantly improved the solubility, dissolution rate, and flowability of SMV. This technique offers a promising strategy for enhancing the bioavailability and pharmaceutical performance of poorly soluble drugs.

An Advanced Twin-Screw Granulation Technology: The use of Non-Volatile Solvents with High Solubilizing Capacity

PurposeTwin-screw wet granulation (TSWG) is a manufacturing process that offers several advantages for the processing of water-insoluble active pharmaceutical ingredients (APIs) and has been used for increasing the solubility and dissolution rates. Here we introduce a novel TSWG approach with reduced downstream processing steps by using non-volatile solvents as granulating binders.MethodsHerein, TSWG was carried out using Transcutol a non-volatile protic solvent as a granulating binder and dissolution enhancer of ibuprofen (IBU) blends with cellulose polymer grades (Pharmacoat® 603, Affinisol™, and AQOAT®).ResultsThe physicochemical characterisation of the produced granules showed excellent powder flow and the complete transformation of IBU into the amorphous state. Dissolution studies presented immediate release rates for all IBU formulations due to the high drug-polymer miscibility and the Transcutol solubilising capacity.ConclusionsOverall, the study demonstrated an innovative approach for the development of extruded granules by processing water-insoluble APIs with non-volatile solvents for enhanced dissolution rates at high drug loadings.Graphical

Preparation and Characterization of Dutasteride Nanoparticles as Oral Fast-Dissolving Film

Background: Dutasteride, is a drug whose mechanism of action is inhibition of the enzyme 5-alpha reductase. It has been approved for use in the treatment of benign prostatic hyperplasia. Dutasteride has low solubility and high permeability, which classifies it as Biopharmaceutics classification system class II, according to the Biopharmaceutics Classification System. It has a water solubility of only 0.038 ng/mL and a slow dissolving rate, resulting in its exclusive availability in the market as a formulation contained within soft gelatin capsules. Objective: The aim of this study involves two parts. First, is the enhancement of dutasteride dissolution rate, by the creation of dutasteride nanosuspension, and second is the enhancement of patient compliance by the transformation of this nanosuspension to oral fast-dissolving film, which is characterized by its fast disintegration, stability, and ease of administration. Methods: The solvent anti/solvent precipitation method was used to formulate dutasteride nanosuspension. In addition, dutasteride nanoparticles oral fast dissolving films were prepared by using the solvent casting method. To compare the in vitro release patterns of pure dutasteride film and selected dutasteride nanoparticles film, the statistical analysis for the dissolution investigation was conducted using the model-independent technique (employing similarity factor f2) utilizing a DD solver. The selected dutasteride nanoparticle film was supposed to be the test material, while the pure dutasteride film was supposed to serve as the reference. Results: dutasteride nanosuspension demonstrated a high enhancement of the dissolution rate. In addition, the prepared dutasteride nanoparticles oral fast-dissolving film exhibited a further increase in the rate of dissolution and fast disintegration, and the administration is easy, all of these properties making it a promising dosage form. Conclusion: Nanosuspension is an excellent approach for enhancing the solubility, dissolution rate, and effectiveness of drugs with limited aqueous solubility such as dutasteride. In addition, the oral fast-dissolving film can be considered a promising dosage form that will increase patient compliance due to its high dissolution rate, fast disintegration, and easy administration.

Ketoprofen-Tromethamine: Binary Phase Diagram of Multicomponent Crystal, Dissolution Rate, and Analgesic Activity Evaluation

Ketoprofen is a non-steroidal anti-inflammatory drug (NSAID) whose formulation options are limited due to its low dissolution rate in aqueous media. This research aimed to enhance the solubility of ketoprofen in distilled water and to compare the anti-inflammatory and analgesic effects of its resulting multicomponent crystal with tromethamine. The binary phase diagram of ketoprofen-tromethamine was created across molar ratios ranging from 1:9 to 9:1. The multicomponent crystal comprising ketoprofen and tromethamine in the selected ratio was synthesized using a solvent drop grinding method and subjected to further characterization for thermal properties, crystallinity, chemical groups, and morphology. The dissolution rate assessments were evaluated in CO2-free distilled water. Pharmacological analyses examined the anti-inflammatory and analgesic effects of the multicomponent crystal. The binary phase analysis identified the 5:5 (1:1) molar ratio as optimal in forming a multicomponent crystal. Thermograms and diffractograms revealed crystalline alterations attributed to a new crystalline phase. The new multicomponent crystal exhibited approximately 2.7 times higher dissolution rate after 30 minutes, outperforming pure ketoprofen. Pharmacological assessments demonstrated superior analgesic effects of the multicomponent crystal. In summary, the ketoprofen-tromethamine cocrystal in 1:1 molar ratio offers enhanced dissolution rate and provides better analgesic activity than ketoprofen alone.

Solubility and Dissolution Rate Enhancement of Aceclofenac by Solid Dispersion Employing Kneading and Solvent Evaporation Techniques

Background: Aceclofenac (ACF) is a non-steroidal anti-inflammatory drug with potent anti-inflammatory and analgesic properties. ACF is belongs to BCS class II which has poor solubility in water (practically insoluble) and high permeability that leads to a low dissolution rate and reduced bioavailability. Objective: to enhance the solubility and dissolution rate of ACF using the solid dispersion method (SD) by two common techniques which were solvent evaporation (SE) and kneading (Kn) by using different carriers Mannitol, PVP k30, Soluplus®, and Urea in both techniques at 1:1 and 1:5 wight ratio. Methods: The effects of type of carrier and preparation method on solubility and dissolution rate of SD were studied. Solid dispersions were characterized for their, percentage yield, drug content, drug solubility and in-vitro dissolution rate in comparison with pure drug. Results: The best formula is obtained by the Kn formula (F16) which was formulated by the use of ACF: Soluplus®: with a weight ratio of 1:5 which gave a high percentage yield (99.5%), high drug content (99.8± 0.003%) and the best solubility enhancement which was 361 folds compared to pure ACF and faster dissolution rate which was 80% in 10 minutes compared to 20% for pure drug. Conclusion: the solubility and in-vitro dissolution rate of ACF was efficiently improved when prepared by SD techniques, utilizing both solvent evaporation and kneading methods. Furthermore, the kneading method was superior to solvent evaporation method due to the greater enhancement of solubility and dissolution rate obtained by all carriers and ratios with higher improvement by 1:5 ratio, and can be considered a successful and efficient strategy for solubility and in-vitro dissolution rate improvement of hydrophobic drugs.

Dissolving microarray patches loaded with a rotigotine nanosuspension: A potential alternative to Neupro® patch

Parkinson's disease (PD), affecting about ten million people globally, presents a significant health challenge. Rotigotine (RTG), a dopamine agonist, is currently administered as a transdermal patch (Neupro®) for PD treatment, but the daily application can be burdensome and cause skin irritation. This study introduces a combinatorial approach of dissolving microarray patch (MAP) and nanosuspension (NS) for the transdermal delivery of RTG, offering an alternative to Neupro®. The RTG-NS was formulated using a miniaturized media milling method, resulting in a nano-formulation with a mean particle size of 274.09 ± 7.43 nm, a PDI of 0.17 ± 0.04 and a zeta potential of −15.24 ± 2.86 mV. The in vitro dissolution study revealed an enhanced dissolution rate of the RTG-NS in comparison to the coarse RTG powder, under sink condition. The RTG-NS MAPs, containing a drug layer and a ‘drug-free’ supporting baseplate, have a drug content of 3.06 ± 0.15 mg/0.5 cm2 and demonstrated greater amount of drug delivered per unit area (∼0.52 mg/0.5 cm2) than Neupro® (∼0.20 mg/1 cm2) in an ex vivo Franz cell study using full-thickness neonatal porcine skin. The in vivo pharmacokinetic studies demonstrated that RTG-NS MAPs, though smaller (2 cm2 for dissolving MAPs and 6 cm2 for Neupro®), delivered drug levels comparable to Neupro®, indicating higher efficiency per unit area. This could potentially avoid unnecessarily high plasma levels after the next dose at 24 h, highlighting the benefits of dissolving MAPs over conventional transdermal patches in PD treatment.

Microfluidics-on-a-chip for designing celecoxib-based amorphous solid dispersions: when the process shapes the product

AbstractThe fundamental idea underlying the use of amorphous solid dispersions (ASDs) is to make the most of the solubility advantage of the amorphous form of a drug. However, the drug stability becomes compromised due to the higher free energy and disorder of molecular packing in the amorphous phase, leading to crystallization. Polymers are used as a matrix to form a stable homogeneous amorphous system to overcome the stability concern. The present work aims to design ASD-based formulations under the umbrella of quality by design principles for improving oral drug bioavailability, using celecoxib (CXB) as a model drug. ASDs were prepared from selected polymers and tested both individually and in combinations, using various manufacturing techniques: high-shear homogenization, high-pressure homogenization, microfluidics-on-a-chip, and spray drying. The resulting dispersions were further optimized, resorting to a 32 full-factorial design, considering the drug:polymers ratio and the total solid content as variables. The formulated products were evaluated regarding analytical centrifugation and the influence of the different polymers on the intrinsic dissolution rate of the CXB-ASDs. Microfluidics-on-a-chip led to the amorphous status of the formulation. The in vitro evaluation demonstrated a remarkable 26-fold enhancement in the intrinsic dissolution rate, and the translation of this formulation into tablets as the final dosage form is consistent with the observed performance enhancement. These findings are supported by ex vivo assays, which exhibited a two-fold increase in permeability compared to pure CXB. This study tackles the bioavailability hurdles encountered with diverse active compounds, offering insights into the development of more effective drug delivery platforms. Graphical Abstract

Generality of Enhancing the Dissolution Rates of Free Acid Amorphous Solid Dispersions by the Incorporation of Sodium Hydroxide.

The incorporation of a counterion into an amorphous solid dispersion (ASD) has been proven to be an attractive strategy to improve the drug dissolution rate. In this work, the generality of enhancing the dissolution rates of free acid ASDs by incorporating sodium hydroxide (NaOH) was studied by surface-area-normalized dissolution. A set of diverse drug molecules, two common polymer carriers (copovidone or PVPVA and hydroxypropyl methylcellulose acetate succinate or HPMCAS), and two sample preparation methods (rotary evaporation and spray drying) were investigated. When PVPVA was used as the polymer carrier for the drugs in this study, enhancements of dissolution rates from 7 to 78 times were observed by the incorporation of NaOH into the ASDs at a 1:1 molar ratio with respect to the drug. The drugs having lower amorphous solubilities showed greater enhancement ratios, providing a promising path to improve the drug release performance from their ASDs. Samples generated by rotary evaporation and spray drying demonstrated comparable dissolution rates and enhancements when NaOH was added, establishing a theoretical foundation to bridge the ASD dissolution performance for samples prepared by different solvent-removal processes. In the comparison of polymer carriers, when HPMCAS was applied in the selected system (indomethacin ASD), a dissolution rate enhancement of 2.7 times by the incorporated NaOH was observed, significantly lower than the enhancement of 53 times from the PVPVA-based ASD. This was attributed to the combination of a lower dissolution rate of HPMCAS and the competition for NaOH between IMC and HPMCAS. By studying the generality of enhancing ASD dissolution rates by the incorporation of counterions, this study provides valuable insights into further improving drug release from ASD formulations of poorly water-soluble drugs.

Ex vivo permeability study and in vitro solubility characterization of oral Canagliflozin self-nanomicellizing solid dispersion using Soluplus® as a nanocarrier

Abstract Background and objective: Self-nanomicellizing solid dispersion SNMSD is a new formulation that combines solid dispersion and nanomicelle strategies; the strategy involves utilizing a suitable carrier that self-assembles into nanomicelles when interacting with gastrointestinal fluids. Canagliflozin, a sodium-glucose cotransporter-2 inhibitor for treating type 2 diabetes, has been linked to poor absorption due to its insolubility in aqueous media. The study aimed to create self-nanomicellizing solid dispersion systems for canagliflozin to overcome its pharmaceutical limitations and improve oral bioavailability. Materials and Methods: Soluplus® was chosen as a nanocarrier to improve canagliflozin solubility after screening several polymers using a phase solubility study. The solvent evaporation method was selected for preparing the solid dispersion. The optimal formula was characterized through ex vivo permeability and in vitro studies. Results: The CFZ-SNMSD formula, with a particle size PS of 60.77±1.00 nm and polydispersity index PDI of 0.06±0.02, has a stable distribution upon dilution to 20-fold with water. The apparent solubility of canagliflozin in the optimized CFZ-SNMSD formula was enhanced by 904.40±4 folds due to amorphization and nanomicellization, as demonstrated by transmission electron microscopy. CFZ-SNMSD formula showed a significant enhancement in dissolution rate compared to the physical mixture and pure drugs. The dissolution efficiency parameter confirms these findings (DE30, CFZ-SNMSD = 77.20% compared to DE30, pure drug = 18.28%). Studies show that canagliflozin’s permeability increases exponentially over time due to Soluplus® dispersibility, solubilization, and glycoprotein inhibitory effect, enhancing bioavailability and overcoming GIT membrane barriers. Conclusions: The study indicates that canagliflozin self-nanomicellizing solid dispersion systems are promising methods for improving the oral bioavailability of canagliflozin medication.

Nucleotides as new co-formers in co-amorphous systems: Enhanced dissolution rate, water solubility and physical stability

Developing co-amorphous systems is an attractive strategy to improve the dissolution rate of poorly water-soluble drugs. Various co-formers have been investigated. However, previous studies revealed that it is a challenge to develop satisfied acidic co-formers, e.g., acidic amino acids showed much poorer co-former properties than neutral and basic amino acids. Only a few acidic co-formers have been reported, such as aspartic acid, glutamic acid, and some other organic acids. Thus, this study aims to explore the possibility of adenosine monophosphate and adenosine diphosphate used as acidic co-formers. Mebendazole, celecoxib and tadalafil were used as the model drugs. The drug-co-former co-amorphous systems were prepared via ball milling and confirmed using XRPD. The dissolution study suggested that the solubility and dissolution rate of the drug-co-formers systems were increased significantly compared to the corresponding crystalline and amorphous drugs. The stability study revealed that using the two nucleotides as co-formers enhanced the physical stability of pure amorphous drugs. Molecular interactions were observed in MEB-co-former and TAD-co-former systems and positively affected the pharmaceutical performance of the investigated co-amorphous systems. In conclusion, the two nucleotides could be promising potential acidic co-formers for co-amorphous systems.

Formulation and Characterization of Clozapine Nanosuspension as a Sublingual Film

Background: Clozapine (CLZ) is a potent antipsychotic drug that suppresses the symptoms of schizophrenia and mania. Clozapine falls into Class II (BCS); its poor bioavailability is attributed to low water solubility and an extensive first-pass effect. Objective: To prepare CLZ as a nanosuspension (NS) to improve its low water solubility and load it into a sublingual film to enhance oral bioavailability. Methods: CLZ nanosuspensions are prepared by the “solvent anti-solvent precipitation” method using Soluplus as a stabilizing agent. We evaluated the polydispersity index (PDI) and the particle size of the CLZ nanosuspension formulations. The optimized formula of CLZ nanosuspension is loaded directly onto a sublingual thin film, eliminating the need for freeze-drying for solidification by the solvent casting approach. The sublingual films were characterized by thickness, surface pH, folding endurance, disintegration time, and in vitro dissolution rate. Results: We selected the formula F1 sublingual film as the best, as it demonstrated a uniform thickness of 0.087mm, good flexibility, and a surface pH of 6.7. It disintegrated quickly in 13 seconds and had a faster in vitro dissolution rate (3 min) compared to the CLZ ordinary films. Conclusions: The results confirmed the success of CLZ NS as a sublingual thin film for dissolution rate enhancement, which may improve oral bioavailability.

Enhanced bioavailability of curcumin amorphous nanocomposite prepared by a green process using modified starch

Curcumin (Cur), a bioactive compound extracted from plants, has attracted widespread attention due to its multiple pharmacological activities. However, the low bioavailability due to the inherent limitations in water solubility, chemical stability, and permeability poses great challenges for realizing its clinical potentials. In the current study, octenyl succinic anhydride-modified starch (OSA-S), a renewable and biodegradable biopolymer, was employed to fabricate Cur amorphous composite nanoparticles (Cur/OSA-S NPs) through a solvent-free pH-driven method with the aim to enhance Cur's bioavailability by improving its solubility and stability. Cur/OSA-S NPs, with mean sizes of about 128.9 ± 8.6 nm, encapsulation efficiencies of about 90.0 %, and the drug loading capacities around 51.0 ± 0.2 %, were successfully prepared. Cur was found to be dispersed within the composite nanoparticles in amorphous state as confirmed by the XRD and DSC characterizations. In addition, Cur/OSA-S NPs offers excellent storage, thermal and light stability, excellent re-dispersibility, and approximately 92 times better solubility than the original Cur. Furthermore, studies of dissolution and the parallel artificial membrane permeability assay (PAMPA) confirmed enhanced dissolution rates and in vitro permeabilities of Cur/OSA-S NPs. Cancer cell viability and uptake experiments revealed that Cur/OSA-S NPs possessed more potent inhibitory effects on cancer cell proliferation compared to the raw Cur. The results obtained from the current study demonstrated the effectiveness of OSA-S for manufacturing Cur amorphous composite nanoparticles with enhanced solubility, stability, and permeability, which might be valuable for further development of Cur based products for treatment of various diseases.

Development and Evaluation of Sulfobutylether-β-cyclodextrin Inclusion Complexes of Etoricoxib for Enhancing Dissolution

Introduction: Etoricoxib is a BCS class II drug with poor aqueous solubility and analgesic and anti-inflammatory properties. Complexation with cyclodextrins is one of the widely used methods, amongst others, for enhancing the solubility and bioavailability of drugs. In current research work, inclusion complexes of etoricoxib using modified forms of cyclodextrin, i.e., captisol were prepared using kneading, evaporation, and freeze-drying methods to improve the solubility and dissolution characteristics. Methods: Etoricoxib inclusion complexes (ratio 1:1) were formulated using kneading, evaporation, and freeze-drying methods. The formulated inclusion complexes were evaluated for phase solubility, equilibrium solubility studies, Fourier transform infrared spectroscopy, powder X-ray diffraction, scanning electron microscopy, differential scanning calorimetry studies, in vitro drug release, similarity factor and in vivo studies. Results: The freeze-drying method produced inclusion complexes with the highest equilibrium solubility (ten times that of the pure drug). Fourier transform infrared spectroscopy studies showed no drug-polymer interaction. Differential scanning calorimetry and scanning electron microscopy studies suggested the incorporation of the drug into inclusion complexes of cyclodextrin. In vitro dissolution studies of kneading, evaporation and freeze-drying method inclusion complexes showed 66.53%, 79.13% and 88% drug release, respectively, in 3h, whereas pure drug exhibited 61.77% drug release in 3 h. The f1 value obtained was less than 50, which is indicative of a significant difference in release characteristics of kneading, evaporation and freeze-drying methods with that of the marketed formulation. In vivo studies indicated that inclusion complexes formulated by the freeze-drying method showed better analgesic and anti-inflammatory effects in comparison to formulations prepared by kneading and evaporation methods. Conclusion: It is concluded that the formulation prepared by the freeze-drying method led to a significant enhancement of dissolution and solubility rate of etoricoxib in comparison to the formulation prepared by the kneading method and evaporation method.