Development of an amorphous nanosuspension by sonoprecipitation-formulation and process optimization using design of experiment methodology

Exploring nalbuphine loaded chitosan nanoparticles for effective pain management through intranasal administration: a comparative study

BACKGROUND

Intranasal drug delivery shows potential for brain access via olfactory and trigeminal routes.

PURPOSE

This work aimed to ensure brain availability of nalbuphine via the nasal route.

METHOD

Chitosan based nanoparticles loaded with nalbuphine were successfully prepared using ionic gelation method and characterised.

RESULT

SEM results revealed that the nanoparticles were spherical in shape, with an average size of 192.4 ± 11.6 nm. Zeta potential and entrapment efficiency was found 32.8 mV and 88.43 ± 7.75%, respectively. The X-ray diffractometry and DSC results unravel a profound understanding on the physical and thermal characteristics. The in-vitro release of nalbuphine from the nanoparticles was biphasic, with an initial burst release followed by a slow-release profile. In-vitro cell study on HEK-293 cells and microscopic images of brain tissue confirmed the safety profile of formulation. In-vivo efficacy studies on animal confirmed the effectiveness of developed intranasal formulation as compared to the standard therapy. The in-vivo pharmacokinetic studies showed that the prepared nanoparticles were able to efficiently deliver nalbuphine to the brain in comparison to the other body organs. Gamma scintigraphy images showed retention of the drug in the brain. Furthermore, the efficacy studies confirmed that the nanoparticles were found significantly more effective than the marketed formulation in pain management.

Design of Experiments-Driven Optimization of Spray Drying for Amorphous Clotrimazole Nanosuspension

This study employed a Quality by Design (QbD) approach to spray dry amorphousclotrimazole nanosuspension (CLT-NS) consisting of Soluplus® and microcrystallinecellulose. Using the Box-Behnken Design, a systematic evaluation was conducted toanalyze the impact of inlet temperature, % aspiration, and feed rate on the criticalquality attributes (CQAs) of the clotrimazole spray-dried nanosuspension (CLT-SDNS). In this study, regression analysis and ANOVA were employed to detect significantfactors and interactions, enabling the development of a predictive model for the spraydrying process. Following optimization, the CLT-SD-NS underwent analysis using Xraypowder diffraction (XRPD), Fourier transform infrared spectroscopy (FTIR), Dynamic Scanning Calorimetry (DSC), and in vitro dissolution studies. The resultsshowed significant variables, including inlet temperature, feed rate, and aspiration rate,affecting yield, redispersibility index (RDI), and moisture content of the final product. The models created for critical quality attributes (CQAs) showed statistical significanceat a p-value of 0.05. XRPD and DSC confirmed the amorphous state of CLT in theCLT-SD-NS, and FTIR indicated no interactions between CLT and excipients. In vitrodissolution studies showed improved dissolution rates for the CLT-SD-NS (3.12-foldincrease in DI water and 5.88-fold increase at pH 7.2 dissolution media), attributed torapidly redispersing nanosized amorphous CLT particles. The well-designed studyutilizing the Design of Experiments (DoE) methodology.

Modelling Drug Delivery to the Small Airways: Optimization Using Response Surface Methodology

AIM

The aim of this in silico study was to investigate the effect of particle size, flow rate, and tidal volume on drug targeting to small airways in patients with mild COPD.

METHOD

Design of Experiments (DoE) was used with an in silico whole lung particle deposition model for bolus administration to investigate whether controlling inhalation can improve drug delivery to the small conducting airways. The range of particle aerodynamic diameters studied was 0.4 - 10 µm for flow rates between 100 - 2000 mL/s (i.e., low to very high), and tidal volumes between 40 - 1500 mL.

RESULTS

The model accurately predicted the relationship between independent variables and lung deposition, as confirmed by comparison with published experimental data. It was found that large particles (~ 5 µm) require very low flow rate (~ 100 mL/s) and very small tidal volume (~ 110 mL) to target small conducting airways, whereas fine particles (~ 2 µm) achieve drug targeting in the region at a relatively higher flow rate (~ 500 mL/s) and similar tidal volume (~ 110 mL).

CONCLUSION

The simulation results indicated that controlling tidal volume and flow rate can achieve targeted delivery to the small airways (i.e., > 50% of emitted dose was predicted to deposit in the small airways), and the optimal parameters depend on the particle size. It is hoped that this finding could provide a means of improving drug targeting to the small conducting airways and improve prognosis in COPD management.

Tannic acid coated nanosuspension for oral delivery of chrysin intended for anti-schizophrenic effect in mice

Chrysin is a flavonoid drug with numerous therapeutic activities. It suffers from low intestinal absorption owing to its hydrophobicity. Therefore, the aim of this study is to exploit the efficient technique of nanosuspension (NSP) to formulate chrysin-NSP coated with tannic acid (TA) to improve the solubility and anti-schizophrenic activity of chrysin. A 23 full factorial design was constructed where the independent factors were type of polymer, surfactant concentration (0.5 or 1 %) and the aqueous phase volume (5 or 15 mL), while the dependent responses were the particle size (PS) of the obtained formulation as well as the % chrysin dissolved after 2 h (Q2h). The optimum formulation (NSP-4) composed of 1 % PEG 400 and 1 % Cremophor RH40 in 15 mL aqueous phase. It achieved a PS and Q2h values of 108.00 nm and 38.77 %, respectively. NSP-4 was then coated with TA (TA-coated NSP-4) for further enhancement of chrysin solubility. TA-coated NSP-4 revealed PS and zeta potential values of 150 ± 14 nm and -32.54 ± 2.45 mV, respectively. After 6 h, chrysin dissolved % were 53.97 and 80.22 for uncoated NSP-4 and TA-coated NSP-4, respectively, compared with only 9.47 for free chrysin. The developed formulations and free chrysin were assessed regarding their effect on schizophrenia induced in mice by cuprizone (CPZ). Treatment with the developed formulations and free chrysin ameliorated demyelination and behavioral deficit induced by CPZ via elevating MBP and PI3K/PKC activities as well as reducing GFAP expression levels. The developed formulations and free chrysin inhibited Galactin-3 and TGF-β expressions and stimulated GST antioxidant enzyme. Furthermore, they maintained the balances in glutamatergic and dopaminergic neurotransmission via modulation on neuregulin-1 and alleviated nuclear pyknosis and degeneration in the neurons. The order of activity was: TA-coated NSP-4 > NSP-4 > free chrysin.

Optimizing Nanosuspension Drug Release and Wound Healing Using a Design of Experiments Approach: Improving the Drug Delivery Potential of NDH-4338 for Treating Chemical Burns

NDH-4338 is a highly lipophilic prodrug comprising indomethacin and an acetylcholinesterase inhibitor. A design of experiments approach was used to synthesize, characterize, and evaluate the wound healing efficacy of optimized NDH-4338 nanosuspensions against nitrogen mustard-induced skin injury. Nanosuspensions were prepared by sonoprecipitation in the presence of a Vitamin E TPGS aqueous stabilizer solution. Critical processing parameters and material attributes were optimized to reduce particle size and determine the effect on dissolution rate and burn healing efficacy. The antisolvent/solvent ratio (A/S), dose concentration (DC), and drug/stabilizer ratio (D/S) were the critical sonoprecipitation factors that control particle size. These factors were subjected to a Box-Behnken design and response surface analysis, and model quality was assessed. Maximize desirability and simulation experiment optimization approaches were used to determine nanosuspension parameters with the smallest size and the lowest defect rate within the 10-50 nm specification limits. Optimized and unoptimized nanosuspensions were prepared and characterized. An established depilatory double-disc mouse model was used to evaluate the healing of nitrogen mustard-induced dermal injuries. Optimized nanosuspensions (A/S = 6.2, DC = 2% w/v, D/S = 2.8) achieved a particle size of 31.46 nm with a narrow size range (PDI = 0.110) and a reduced defect rate (42.2 to 6.1%). The optimized nanosuspensions were stable and re-dispersible, and they showed a ~45% increase in cumulative drug release and significant edema reduction in mice. Optimized NDH-4338 nanosuspensions were smaller with more uniform sizes that led to improved physical stability, faster dissolution, and enhanced burn healing efficacy compared to unoptimized nanosuspensions.

Revolutionizing Psoriasis Topical Treatment: Enhanced Efficacy Through Ceramide/Phospholipid Composite Cerosomes Co-Delivery of Cyclosporine and Dithranol: In-Vitro, Ex-Vivo, and in-Vivo Studies

Purpose

Improving the treatment of psoriasis is a serious challenge today. Psoriasis is an immune-mediated skin condition affecting 125 million people worldwide. It is commonly treated with cyclosporine-A (CsA) and dithranol (DTH). CsA suppresses the activation of T-cells, immune cells involved in forming psoriatic lesions. Meanwhile, DTH is a potent anti-inflammatory and anti-proliferative drug that effectively reduces the severity of psoriasis symptoms such as redness, scaling, and skin thickness. CsA and DTH belong to BCS class II with limited oral bioavailability. We aim to develop a drug delivery system for topical co-delivery of CsA and DTH, exploring its therapeutic potential.

Methods

Firstly, we developed a niosomal drug delivery system based on ceramide IIIB to form Cerosomes. Cerosomes were prepared from a mixture of Ceramide, hyaluronic acid, and edge activator using a thin-film hydration technique. To co-deliver CsA and DTH topically for the treatment of psoriasis. These two hydrophobic drugs encapsulated into our synthesized positively charged particle cerosomes.

Results

 Cerosomes had an average particle size of (222.36 nm± 0.36), polydispersity index of (0.415±0.04), Entrapment Efficiency of (96.91%± 0.56), and zeta potential of (29.36±0.38mV) for selected formula. In vitro, In silico, in vivo, permeation, and histopathology experiments have shown that cerosomes enhanced the skin penetration of both hydrophobic drugs by 66.7% compared to the CsA/DTH solution. Imiquimod (IMQ) induced psoriatic mice model was topically treated with our CsA/DTH cerosomes. We found that our formulation enhances the skin penetration of both drugs and reduces psoriasis area and severity index (PASI score) by 2.73 times and 42.85%, respectively, compared to the CsA/DTH solution. Moreover, it reduces the levels of proinflammatory cytokines, TNF-α, IL-10, and IL-6 compared to CsA/DTH solution administration.

Conclusion

The Cerosomes nano-vesicle-containing CsA/DTH represents a more promising topical treatment for psoriasis, giving new hope to individuals with psoriasis, compared to commercial and other conventional alternatives.

Development of canagliflozin nanocrystals sublingual tablets in the presence of sodium caprate permeability enhancer: formulation optimization, characterization, in-vitro, in silico, and in-vivo study

Canagliflozin (CFZ) is a sodium-glucose cotransporter-2 inhibitor (SGLT2) that lowers albuminuria in type-2 diabetic patients, cardiovascular, kidney, and liver disease. CFZ is classified as class IV in the Biopharmaceutical Classification System (BCS) and is characterized by low permeability, solubility, and bioavailability, most likely attributed to hepatic first-pass metabolism. Nanocrystal-based sublingual formulations were developed in the presence of sodium caprate, as a wetting agent, and as a permeability enhancer. This formulation is suitable for children and adults and could enhance solubility, permeability, and avoid enterohepatic circulation due to absorption through the sublingual mucosa. In the present study, formulations containing various surfactants (P237, P338, PVA, and PVP K30) were prepared by the Sono-homo-assisted precipitation ion technique. The optimized formula prepared with PVP-K30 showed the smallest particle size (157 ± 0.32 nm), Zeta-potential (-18 ± 0.01), and morphology by TEM analysis. The optimized formula was subsequently formulated into a sublingual tablet containing Pharma burst-V® with a shorter disintegration time (51s) for the in-vivo study. The selected sublingual tablet improved histological and biochemical markers (blood glucose, liver, and kidney function), AMP-activated protein kinase (AMPK), and protein kinase B (AKT) pathway compared to the market formula, increased CFZ's antidiabetic potency in diabetic rabbits, boosted bioavailability by five-fold, and produced faster onset of action. These findings suggest successful treatment of diabetes with CFZ nanocrystal-sublingual tablets.

Preparation of Piroxicam nanosuspensions by high pressure homogenization and evaluation of improved bioavailability

OBJECTIVE

Inflammation is a natural response of the organism, involving events responsible for releasing chemical mediators and requiring treatments of symptoms such as pain, redness, heat, swelling, and loss of tissue function. Piroxicam (PRX) is a non-steroidal anti-inflammatory drug with the effect of nonselective COX inhibitor activity; however, it shows poor bioavailability caused by the poor and slow water solubility. In this study, we developed PRX nanosuspensions with 200-500 nm in diameter to increase the bioavailability of PRX by improving its solubility.

METHODS

PRX nanosuspensions were fabricated by High pressure homogenization method with PVA, SDS and Tween 80. The nanosuspensions were characterized by XRD, FTIR, DSC, and in vitro release. In vivo pharmacokinetic properties and anti-inflammatory effects were also investigated in rabbits.

RESULTS

PRX nanosuspensions significantly increased the solubility (14.89 ± 0.03 mg/L for pure PRX and 16.75 ± 0.05 mg/L for PRX nanosuspensions) and dissolution rate as compared to the pure PRX (p < 0.05). Orally administered PRX nanosuspension (AUC 0-t is 49.26 ± 4.29 μg/mL × h) significantly improved the bioavailability of PRX (AUC 0-t is 28.40 ± 12.11 μg/mL × h). The anti-inflammatory effect of PRX nanosuspension was also investigated in rabbits and it was observed that PRX nanosuspension treatment significantly improved the inhibition of COX-2 and NFκB expression as compared to the PRX treatment (p < 0.05).

CONCLUSIONS

The results in this study indicate that PRX nanosuspension is a promising nanomedicine for enhancing the anti-inflammatory activity of PRX and has a high potential for the treatment of inflammation.

Nanosuspensions as carriers of active ingredients: Chemical composition, development methods, and their biological activities

Nanosuspensions (NSps) are colloidal dispersions of particles that have the potential to solve the delivery problems of active ingredients associated with their low solubility in water or instability due to environmental factors. It is essential to consider their chemical composition and preparation methods because they directly influence drug loading, size, morphology, solubility, and stability; these characteristics of nanosuspensions influence the delivery and bioavailability of active ingredients. NSps provides high loading of drugs, protection against degrading agents, rapid dissolution, high particle stability, and high bioavailability of active ingredients across biological membranes. In addition, they provide lower toxicity compared to other nanocarriers, such as liposomes or polymeric nanoparticles, and can modify the pharmacokinetic profiles, thus improving their safety and efficacy. The present review aims to address all aspects related to the composition of NSps, the different methods for their production, and the main factors affecting their stability. Moreover, recent studies are described as carriers of active ingredients and their biological activities.

Fabrication and optimization of itraconazole-loaded zein-based nanoparticles in coated capsules as a promising colon-targeting approach pursuing opportunistic fungal infections

Itraconazole (ITZ), a broad-spectrum antifungal drug, was formulated into colon-targeting system aiming to treat opportunistic colonic fungal infections that commonly infect chronic inflammatory bowel diseases (IBD) patients due to immunosuppressive therapy. Antisolvent precipitation technique was employed to formulate ITZ-loaded zein nanoparticles (ITZ-ZNPs) using various zein: drug and aqueous:organic phase ratios. Central composite face-centered design (CCFD) was used for statistical analysis and optimization. The optimized formulation was composed of 5.5:1 zein:drug ratio and 9.5:1 aqueous:organic phase ratio with its observed particle size, polydispersity index, zeta potential, and entrapment efficiency of 208 ± 4.29 nm, 0.35 ± 0.04, 35.7 ± 1.65 mV, and 66.78 ± 3.89%, respectively. ITZ-ZNPs were imaged by TEM that revealed spherical core-shell structure, and DSC proved ITZ transformation from crystalline to amorphous form. FT-IR showed coupling of zein NH group with ITZ carbonyl group without affecting ITZ antifungal activity as confirmed by antifungal activity test that showed enhanced activity of ITZ-ZNPs over the pure drug. Histopathological examination and cytotoxicity tests ensured biosafety and tolerance of ITZ-ZNPs to the colon tissue. The optimized formulation was then loaded into Eudragit S100-coated capsules and both in vitro release and in vivo X-ray imaging confirmed the success of such coated capsules in protecting ITZ from the release in stomach and intestine while targeting ITZ to the colon. The study proved that ITZ-ZNPs is promising and safe nanoparticulate system that can protect ITZ throughout the GIT and targeting its release to the colon with effectual focused local action for the treatment of colon fungal infections.

A quality by design framework for developing nanocrystal bioenabling formulations

The present study aims to outline a rational framework for the design and development of a 1.0% (w/v) hydrocortisone nanocrystal-based formulation, resorting to a simple, efficient, and scalable nanonization methodology, based on the high-pressure homogenization (HPH) technique. Accordingly, the innovative product was comprehensively optimized following a Quality by Design (QbD) approach. The thorough selection of formulation composition was driven by a dual purpose: improving skin permeation and stability. In the early stage of development, a Failure Mode, Effects and Criticality Analysis (FMECA) diagram was employed to identify the most impactful variables for the critical quality attributes (CQAs). In this sense, a rotatable, three-factor and five-level circumscribed central composite design (CCCD) was applied to investigate how squalene concentration (x1), soluplus concentration (x2) and HPH-time (x3) influence physicochemical properties, performance and physical stability of the formulation. A robust Design Space (DS) was defined, establishing the optimal settings for the critical variables, whose combination meets the requirements set in the quality target product profile (QTPP). Morphological analysis revealed the cuboidal shape of hydrocortisone nanocrystals. In what concerns colloidal properties, the most promising formulation disclosed a small particle size (Dx(50) = 311.8 ± 1.5 nm), along with narrow size distribution (span value = 1.91 ± 0.17). Zeta potential results (-2.19 ± 0.15 mV--12.1 ± 0.4 mV) suggested a steric hindrance stabilization. FTIR spectra showed no chemical interactions between drug and formulation components. XRD diffractograms confirmed loss of crystallinity during the downsizing process. In vitro studies revealed an improvement on drug release rate (316 ± 21-516 ± 35 μg/cm2/√t), compared to the coarse suspension and commercial products, and a straight dependence on the stabilizer concentration and HPH time. The permeation flux across the skin (0.16 ± 0.02-1.2 ± 0.5 μg/cm2/h) appeared to be dependent on the drug physicochemical properties, in particular saturation solubility. Further characterization of the experimental formulations pointed out the role of the stabilizing component to prevent against physical instability phenomena. This organic solvent-free, and therefore "green" nanocrystal production technology offers great potential for pharmaceutical R&D and drug delivery by enabling the development of new forms of conventional drugs with optimal physicochemical properties and performance.

Systematic Screening Study for the Selection of Proper Stabilizers to Produce Physically Stable Canagliflozin Nanosuspension by Wet Milling Method

One of the crucial approaches to managing the low solubility and weak bioavailability of drugs is via nanocrystal technology. Through this technology, drug particles have an increased solubility and a faster dissolution rate due to high surface free energy, which requires an appropriate stabilizer(s) to prevent instabilities during the manufacturing process and storage of the nanosuspension. This study aimed to establish a scientific predictive system for properly selecting stabilizers or to reduce the attempts on a trial-and-error basis in the wet-milling method. In total, 42 experiments were performed to examine the effect of critical material attributes on the wettability of the drug, the saturation solubility in the stabilizer solutions or combinations thereof and the dynamic viscosity of stabilizer solutions. All data were evaluated by Minitab 19® and an optimization study was performed. The optimized formulation at a certain concentration of stabilizer combination was ground by Dyno Mill® with 0.3 mm beads for one hour. The optimized nanosuspension with a particle size of 204.5 nm was obtained in short milling time and offered 3.05- and 3.51 times better dissolution rates than the marketed drug product (Invokana® 100 mg) in pH 4.5 and pH 6.8 as non-sink conditions, respectively. The formulation was monitored for three months at room temperature and 4 °C. The parameters were 261.30 nm, 0.163, -14.1 mV and 261.50 nm, 0.216 and -17.8 mV, respectively. It was concluded that this approach might indicate the appropriate selection of stabilizers for the wet-milling process.

Formulation and Characterization of Ursodeoxycholic Acid Nanosuspension Based on Bottom-Up Technology and Box-Behnken Design Optimization

BACKGROUND

Ursodeoxycholic acid (UDCA) is a therapeutic agent used for the treatment of cholestatic hepatobiliary diseases in pediatric patients. It is a bile acid that presents high lipophilicity, and it belongs to Class II of the Biopharmaceutical Classification System (BCS), which exhibits low water solubility and high intestinal permeability, which leads to poor oral absorption. The objective of this work was to design and optimize UDCA nanosuspensions by means of the precipitation-ultrasonication method to improve the solubility, dissolution, and oral bioavailability of UDCA.

METHODS

A three-level, three-factor Box-Behnken design was used to optimize formulation variables and obtain uniform, small-particle-size UDCA nanosuspensions. The independent variables were: stabilizer percentage (X1), amplitude (X2), and sonication time (X3), and the dependent variable was the particle size (Y1). In the precipitation-ultrasonication method, UDCA was dissolved in acetone:PEG 400 (1:1 v/v) and quickly incorporated into the antisolvent (pre-cooled aqueous dispersion of HPMC E-15 0.3%), by means of intense sonication at 50 W for 5 min, controlling temperature through an ice water bath. The lyophilization efficacy was evaluated by means of a cryoprotective efficacy test, working with 10% maltose at -80 °C. The nanosuspensions were characterized by dynamic light scattering (DLS), X-ray diffraction, and scanning electron microscopy (SEM). The physicochemical stability was determined at 25 °C and 4 °C at 7, 14, 30, and 60 days, and the UDCA content was analyzed via HPLC-UV. An in vitro dissolution assay and an oral bioavailability study were performed in male Wistar rats.

RESULTS

A significant impact was achieved in the optimized nanosuspension with 0.3% (stabilizer), 50 W (amplitude), and 5 min (sonication time), with a particle size of 352.4 nm, PDI of 0.11, and zeta potential of -4.30 mV. It presented adequate physicochemical stability throughout the study and the UDCA content was between 90% and 110%. In total, 86% of UDCA was dissolved in the in vitro dissolution test. The relative oral bioavailability was similar without significant statistical differences when comparing the lyophilized nanosuspension and the commercial tablet, the latter presenting a more erratic behavior. The pharmacokinetic parameters of the nanosuspension and the commercial tablet were Tmax (1.0 ± 0.9 h vs. 2.0 ± 0.8 h, respectively), Cmax (0.558 ± 0.118 vs. 0.366 ± 0.113 µM, respectively), ΔCmax (0.309 ± 0.099 vs. 0.232 ± 0.056, respectively), AUC (4.326 ± 0.471 vs. 2.188 ± 0.353 µg/mL.h, respectively, p < 0.02), and IAUC0-24h (2.261 ± 0.187 µg/mL.h vs. 1.924 ± 0.440 µg/mL.h, respectively).

CONCLUSIONS

The developed nanosuspension presents an appropriate dosage and administration for pediatric patients. On the other hand, it exhibits an adequate absorption and UDCA oral bioavailability.

Strategizing Spray Drying Process Optimization for the Manufacture of Redispersible Indomethacin Nanoparticles Using Quality-by-Design Principles

The present study adopted a Quality by Design (QbD) approach to spray dry indomethacin nanosuspension (IMC-NS) consisting of HPC-SL, poloxamer 407, and lactose monohydrate. The Box-Behnken Design was used to systematically evaluate the effects of inlet temperature, aspiration rate, and feed rate on the critical quality attributes (CQAs) [redispersibility index (RDI; minimize), % yield (maximize), and % release at 15 min (maximize)] of the indomethacin spray dried nanosuspension (IMC-SD-NS). To identify significant main and quadratic effects, two-way interactions, and create a predictive model for the spray drying process, regression analysis and ANOVA were utilized. Following optimization, the IMC-SD-NS was analyzed for its physicochemical properties using X-ray powder diffraction (XRPD), Fourier transform infrared spectroscopy (FTIR), and in vitro dissolution studies. Statistical analysis revealed significant independent variables, including inlet temperature, feed rate, and aspiration rate, that critically impacted the solidified end product's RDI, % yield, and % release at 15 min. The models developed for critical quality attributes (CQAs) were significant at a p-value of 0.05. The crystalline state of IMC was maintained in the solidified product, as confirmed by XRPD, and no interactions were observed between IMC and the excipients as evaluated by FTIR. In vitro dissolution studies showed improved dissolution rate for the IMC-SD-NS (3.82-fold increase in overall drug release), which may be attributed to the readily redispersible nanosized drug particles. The implementation of a well-designed study, utilizing Design of Experiments (DoE) methodology, played a crucial role in the development of a highly effective spray drying process.

Developing a Formulation Strategy Coupled with PBPK Modeling and Simulation for the Weakly Basic Drug Albendazole

Albendazole (ABZ) is a weakly basic drug that undergoes extensive presystemic metabolism after oral administration and converts to its active form albendazole sulfoxide (ABZ_SO). The absorption of albendazole is limited by poor aqueous solubility, and dissolution is the rate-limiting step in the overall exposure of ABZ_SO. In this study, PBPK modeling was used to identify formulation-specific parameters that impact the oral bioavailability of ABZ_SO. In vitro experiments were carried out to determine pH solubility, precipitation kinetics, particle size distribution, and biorelevant solubility. A transfer experiment was conducted to determine the precipitation kinetics. A PBPK model for ABZ and ABZ_SO was developed using the Simcyp™ Simulator based on parameter estimates from in vitro experiments. Sensitivity analyses were performed to assess the impact of physiological parameters and formulation-related parameters on the systemic exposure of ABZ_SO. Model simulations predicted that increased gastric pH significantly reduced ABZ absorption and, subsequently, ABZ_SO systemic exposure. Reducing the particle size below 50 µm did not improve the bioavailability of ABZ. Modeling results illustrated that systemic exposure of ABZ_SO was enhanced by increasing solubility or supersaturation and decreasing the drug precipitation of ABZ at the intestinal pH level. These results were used to identify potential formulation strategies to enhance the oral bioavailability of ABZ_SO.

Exploring the translocation behaviours in vivo of herpetrione amorphous nanoparticles via oral delivery

Nanotechnology has been a primary strategy to enhance oral bioavailability of poorly water soluble drugs. However, the limited information in vivo fate of impedes the development of nanoparticles via the oral delivery, especially the amorphous nanoparticles with high energy states are rarely reported. This study is to track the translocation of oral herpetrione amorphous nanoparticles (HPE-ANPs). We prepare amorphous particles (ANPs) of various sizes (200 nm and 450 nm), which are embedded with an aggregation-caused quenching (ACQ) dyes for tracking the intact nanoparticles. Nanoparticles remain in the gastrointestinal tract (GIT) for 8 h following oral administration, suggesting that most ANPs was mainly degraded or absorbed in the small intestine. Ex vivo imaging shows that the fluorescent signals are observed in the GIT and liver but not in other organs, which attributed to low absorption of integral nanoparticles. Besides, HPE-ANPs may be directly interact with GIT epithelia, and ileum provides better absorption than the jejunum. Cellular studies prove that integral HPE-ANPs can be taken up by enterocyte, while it penetrates cell monolayers only small amounts. In conclusion, we speculate that the drug in the form of integral nanoparticles and small molecules may be co-absorbed to improve bioavailability in vivo.

Nanosuspension: A Formulation Technology for Tackling the Poor Aqueous Solubility and Bioavailability of Poorly Soluble Drugs

The poor water solubility of numerous novel drug candidates presents significant challenges, particularly in terms of oral administration. This limitation can result in various undesirable clinical implications, such as inter-patient variability, poor bioavailability, difficulties in achieving a safe therapeutic index, increased costs, and potential risks of toxicity or inefficacy. Biopharmaceutics Classification System (BCS) class II drugs face particular hurdles due to their limited solubility in the aqueous media of the gastrointestinal tract. In such cases, parenteral administration is often employed as an alternative strategy. To address these challenges, nanosuspension techniques offer a promising solution for enhancing drug solubility and overcoming oral delivery obstacles. This technique has the potential to bridge the gap between drug discovery and preclinical use by resolving problematic solubility. This literature review has delved into contemporary nanosuspension preparation technologies and the incorporation of stabilizing ingredients within the formulation. Furthermore, the manuscript explores nanosuspension strategies for both oral and parenteral/other delivery routes, and separate discussions have been presented to establish a suitable flow that addresses the challenges and strategies relevant to each administration method.

Nanosizing Coamorphous Drugs Using Top-Down Approach: The Effect of Particle Size Reduction on Dissolution Improvement

Nanotechnology and coamorphous are both advanced technologies that can effectively improve the solubility of drugs. This study has been the first attempt to combine these two approaches to construct the coamorphous nanoparticles to improve the dissolution and investigated the effect of physical properties of coamorphous solid on the nanosizing process. Two types of coamorphous solid, i.e., curcumin-artemisinin and quercetin-lysine, were selected as models. Coamorphous curcumin-artemisinin could highly contribute to the size reduction during milling compared to the crystalline form, which might attribute to the change of crystallinity. Nanosized coamorphous curcumin-artemisinin showed higher dissolution than nanocrystals and single coamorphous sample. However, quercetin-lysine coamorphous nanoparticles did not reflect significant dissolution improvement compared with the microsized sample. The difference of initial dissolutions for both could be the main reason. The directly mixing and drying method was confirmed to be an effective and simple approach to maintain the dissolution of nanosized coamorphous sample.

The Impact of Process and Formulation Parameters on the Fabrication of Efavirenz Nanosuspension to Improve Drug Solubility and Dissolution

Background

Efavirenz nanosuspensions (EZ-NSs) were developed by the wet milling method as the most promising top-down nanosizing technique. Different process and formulation parameters were studied and optimized to produce appropriate EZ-NS in suitable conditions to enhance drug dissolution.

Methods

In the preliminary studies, various polymeric stabilizers, including Pluronic F68, sodium carboxymethylcellulose (CMC), hydroxypropyl methylcellulose (HPMC), and polyvinyl alcohol (PVA), as well as different sizes and weight of milling beads were used to prepare NSs. The effect of sodium lauryl sulfate (SLS) concentration on the NS properties was also evaluated. The influence of other formulation and process parameters, including polymer concentration, milling speed, and milling time, on the particle size and distribution of NSs were investigated using Box-Behnken design. The optimized freeze-dried nanosuspension was characterized by redispersibility, physicochemical properties, and stability.

Results

A combination of PVA and SLS was selected as steric and electrostatic stabilizers. The optimum EZ-NS displayed a uniform size distribution with a mean particle size and zeta potential of 254.4 nm and 21.1 mV, respectively. The solidified nanosuspension was well redispersed to the original nanoparticles. Significantly enhanced aqueous solubility (about 11-fold) and accelerated dissolution rate were observed for the optimized formulation. This could be attributed to the reduced particle size and partial amorphization of EZ during the preparation process, studied by X-ray diffraction. Accelerated studies confirmed the stability of the optimum freeze-dried formulation over the examined period of three months.

Conclusions

Optimization of different variables led to the formation of EZ-NSs with desired properties through wet milling in a very short time compared to the previous study and therefore reduced production costs. This formulation seems to be a suitable approach for solubility and dissolution enhancement of EZ and may have a great potential to improve the drug's oral bioavailability.

Metronidazole nanosuspension loaded dissolving microarray patches: An engineered composite pharmaceutical system for the treatment of skin and soft tissue infection

Bacteroides fragilis is one of the most common causative group of microorganisms that is associated with skin and soft tissue infections (SSTI). Metronidazole (MTZ) is the drug of choice used in the treatment of SSTI caused by the bacterium. However, owing to its physiochemical properties, MTZ have limited skin permeation, which render the drug unsuitable for the treatment of deep-rooted SSTIs. One strategy to overcome this limitation is to reformulate MTZ into nanosuspension which will then be loaded into dissolving microarray patches (MAPs) for the treatment of SSTIs caused by B. fragilis. Herein, we report for the first time on the preparation and optimisation of MAP loaded with MTZ nanosuspension (MTZ-NS). After screening a range of polymeric surfactants, we identified that Soluplus® resulted in the formation of MTZ-NS with the smallest particle size (115 nm) and a narrow PDI of 0.27. Next, the MTZ-NS was further optimised using a design of experiments (DoE) approach. The optimised MTZ-NS was then loaded into dissolving MAPs with varying MTZ-NS content. Furthermore, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) and cell proliferation assays along with LIVE/DEAD™ staining on the 3T3L1 cell line showed that the MTZ-NS loaded dissolving MAPs displayed minimal toxicity and acceptable biocompatibility. In vitro dermatokinetic studies showed that the MTZ-NS loaded MAPs were able to deliver the nitroimidazole antibiotic across all strata of the skin resulting in a delivery efficiency of 95 % after a 24-hour permeation study. Lastly, agar plating assay using bacterial cultures of B. fragilis demonstrated that MTZ-NS loaded MAP resulted in complete bacterial inhibition in the entire plate relative to the control group. Should this formulation be translated into clinical practice, this pharmaceutical approach may provide a minimally invasive strategy to treat SSTIs caused by B. fragilis.

Process Modelling, Scale-Up and Characterization of Acetaminophen Spray Dried Milk Powder as Novel Pediatric Dosage Form

PURPOSE

Successful drug therapy in children is contingent upon hassle-free administration of pediatric dosage forms. Pediatric patients suffer from difficulty in swallowing due to weak esophagus muscles in their early age. Considering this challenge liquid formulations are preferred over solid dosage form among pediatric patients to avoid the possibility of choking which can be a serious life-threatening condition in children. The main aim of the present research work was to develop a reconstitutable amorphous acetaminophen spray-dried milk powder (ASDM) as novel pediatric formulation.

METHODS

ASDM was prepared by spray drying process and the spray drying process was optimized using Box-Behnken design to study the effect of spray drying process parameters at X₁ [inlet temperature], X₂ [aspiration rate] and X₃ [feed rate] to Y₁ [% yield], Y₂ [angle of repose], Y₃ [Hausner's Ratio] and Y₄ [Carr's Index] as dependent variables of ASDM. In addition, each batch was characterized for particle size by polarized light microscopy and drug entrapment.

RESULTS

Predicted parameters from optimized spray drying process model were successfully employed to manufacture a scale up cum validation batch of ASDM, which showed notably improved yield and desirable flow properties. The scale-up validation batch was further characterized using thermal analysis, diffraction studies, spectroscopic analysis, dispersion studies, stability APAP in dispersion formulation and formulation stability studies to confirm the physico-chemical stability of ASDM.

CONCLUSIONS

Thus, ASDM for oral use can serve as a promising pediatric formulation and the developed prototype formulation can be further extended to future newly discovered drugs with similar characteristics.

Exploring the influence factors and improvement strategies of drug polymorphic transformation combined kinetic and thermodynamic perspectives during the formation of nanosuspensions

Nanosuspensions can effectively increase saturation solubility and improve the bioavailability of poorly water-soluble drugs attributed to high loading and surface-to-volume ratio. Wet media milling has been regarded as a scalable method to prepare nanosuspensions because of its simple operation and easy scale-up. In recent years, besides particle aggregation and Ostwald ripening, polymorphic transformation induced by processing has become a critical factor leading to the instability of nanosuspensions. Therefore, this review aims to discuss the influence factors comprehensively and put forward the corresponding improvement strategies of polymorphic transformation during the formation of nanosuspensions. In addition, this review also demonstrates the implication of molecular simulation in polymorphic transformation. The competition between shear-induced amorphization and thermally activated crystallization is the global mechanism of polymorphic transformation during media milling. The factors affecting the polymorphic transformation and corresponding improvement strategies are summarized from formulation and process parameters perspectives during the formation of nanosuspensions. The development of analytical techniques has promoted the qualitative and quantitative characterization of polymorphic transformation, and some techniques can in-situ monitor dynamic transformation. The microhydrodynamic model can be referenced to study the stress intensities by analyzing formulation and process parameters during wet media milling. Molecular simulation can be used to explore the possible polymorphic transformation based on the crystal structure and energy. This review is helpful to improve the stability of nanosuspensions by regulating polymorphic transformation, providing quality assurance for nanosuspension-based products.

Multi-directionally evaluating the formation mechanism of 1,4-dihydropyridine drug nanosuspensions through experimental validation and computer-aided drug design

The poor aqueous solubility of 1,4-dihydropyridine drugs needs to be solved urgently to improve the bioavailability. Nanotechnology can improve drug solubility and dissolution by reducing particle size, but usually a specific polymer or surfactant is required for stabilization. In this study, Poloxamer-407(P-407) was screened as the optimal stabilize through energy simulation, molecular docking and particle size. morphological study, X-ray diffraction, differential scanning calorimetry, Fourier transform infrared spectroscopy, Raman, in vitro dissolution test and molecular simulation of interactions were utilized to explore the formation mechanisms of four 1,4-dihydropyridine drugs/P-407 nanosuspensions. The result shows that the optimized nanosuspensions had the particle size in the nano-size range and maintained the original crystal state. The in vitro dissolution rate of the nanosuspension was 3-4 times higher than the corresponding API and could reduce the restriction of drug dissolution in different pH environments. Raman spectroscopy, FTIR and molecular docking simulations provided strong supporting evidence for the formation mechanism of 1,4-dihydropyridine drugs/P-407 nanosuspensions at the molecular level, which confirmed that the stable intermolecular hydrogen bond adsorption and hydrophobic interaction were formed between the drug and P-407. This research will provide practical concepts and technologies, which are helpful to develop nanosuspensions for the same class of drugs.

A Systematic Approach to the Development of Cilostazol Nanosuspension by Liquid Antisolvent Precipitation (LASP) and Its Combination with Ultrasound

Nanosizing is an approach to improve the dissolution rate of poorly soluble drugs. The first aim of this work was to develop nanosuspension of cilostazol with liquid antisolvent precipitation (LASP) and its combination with ultrasound. Second, to systematically study the effect of bottom-up processing factors on precipitated particles’ size and identify the optimal settings for the best reduction. After solvent and stabilizer screening, in-depth process characterization and optimization was performed using Design of Experiments. The work discusses the influence of critical factors found with statistical analysis: feed concentration, stabilizer amount, stirring speed and ultrasound energy governed by time and amplitude. LASP alone only generated particle size of a few microns, but combination with ultrasound was successful in nanosizing (d10 = 0.06, d50 = 0.33, d90 = 1.45 µm). Micro- and nanosuspension’s stability, particle morphology and solid state were studied. Nanosuspension displayed higher apparent solubility than equilibrium and superior dissolution rate over coarse cilostazol and microsuspension. A bottom-up method of precipitation-sonication was demonstrated to be a successful approach to improve the dissolution characteristics of poorly soluble, BCS class II drug cilostazol by reducing its particle size below micron scale, while retaining nanosuspension stability and unchanged crystalline form.

Understanding the Impact of Multi-factorial Composition on Efficient Loading of the Stable Ketoprofen Nanoparticles on Orodispersible Films Using Box-Behnken Design

The purpose of the present study was to prepare Orodispersible films (ODFs) loaded with ketoprofen nanoparticles (KT-NP). The Box-Behnken design was constructed in developing and optimizing the KTF-NP-ODFs. The effect of independent variables: Soluplus® concentration (X₁, stabilizer), Tween 80 concentration (X₂, surfactant), and KTF concentration (X₃, drug) were studied on the dependent variables: particle size (PS, Y₁), zeta potential (ZP, Y₂), and the polydispersity index (PDI, Y₃) of the NPs, as well as on the tensile strength (TS, Y₄) and permeability coefficient (PC, Y₅) of the KTF-NP-ODFs. Hydroxypropyl methylcellulose (HPMC E15) and polyethylene glycol (PEG 400) were used as the film former polymer and plasticizer, respectively, and their concentrations were kept constant for all formulations. KTF-NPs were prepared by antisolvent precipitation technology. This was followed by the addition of HPMC E15 and PEG 400 to prepare the ODFs using the solvent-casting method. The PS, PDI, and ZP for all the formulations were found in the range of 94 nm to 350 nm, 0.09 to 0.438, and -21.83 mV to -8.03 mV, respectively. The TS and PC of the prepared KTF-NP-ODFs were found between 1.21 MPa to 3.93 MPa and 3.12 × 10^-4 cm/h to 34.23 × 10^-4 cm/h, respectively. The amorphous nature of the KTF-NP in the ODFs was confirmed by the absence of characteristic crystalline peaks and endothermic events of KTF in X-ray diffraction (XRD) and modulated differential scanning calorimetry (mDSC), respectively. The optimized formulation showed ̴ 4 times higher permeability as compared to the pure KTF. In addition, the dissolution of pure KTF and the optimized KTF-NP-ODF in pH 1.2 at the end of 60 min was found to be ̴ 30% and ̴ 95%, respectively. Conclusively, KTF-NP-ODFs can be a promising drug delivery system to counter the issues related to dysphagia and bypass the common side effects, such as the gastric irritation associated with NSAIDs like KTF.

Improved Bioavailability of Ebastine through Development of Transfersomal Oral Films

The main objective of this research work was the development and evaluation of transfersomes integrated oral films for the bioavailability enhancement of Ebastine (EBT) to treat allergic rhinitis. The flexible transfersomes, consisting of drug (EBT), lipid (Phosphatidylcholine) and edge activator (EA) Polyoxyethylene sorbitan monooleate or Sorbitan monolaurate, were prepared with the conventional thin film hydration method. The developed transfersomes were further integrated into oral films using the solvent casting method. Transfersomes were evaluated for their size distribution, surface charge, entrapment efficiency (EE%) and relative deformability, whereas the formulated oral films were characterized for weight, thickness, pH, folding endurance, tensile strength, % of elongation, degree of crystallinity, water content, content uniformity, in vitro drug release and ex vivo permeation, as well as in vivo pharmacokinetic and pharmacodynamics profile. The mean hydrodynamic diameter of transfersomes was detected to be 75.87 ± 0.55 nm with an average PDI and zeta potential of 0.089 ± 0.01 and 33.5 ± 0.39 mV, respectively. The highest deformability of transfersomes of 18.52 mg/s was observed in the VS-3 formulation. The average entrapment efficiency of the transfersomes was about 95.15 ± 1.4%. Transfersomal oral films were found smooth with an average weight, thickness and tensile strength of 174.72 ± 2.3 mg, 0.313 ± 0.03 mm and 36.4 ± 1.1 MPa, respectively. The folding endurance, pH and elongation were found 132 ± 1, 6.8 ± 0.2 and 10.03 ± 0.4%, respectively. The ex vivo permeability of EBT from formulation ETF-5 was found to be approximately 2.86 folds higher than the pure drug and 1.81 folds higher than plain film (i.e., without loaded transfersomes). The relative oral bioavailability of ETF-5 was 2.95- and 1.7-fold higher than that of EBT-suspension and plain film, respectively. In addition, ETF-5 suppressed the wheal and flare completely within 24 h. Based on the physicochemical considerations, as well as in vitro and in vivo characterizations, it is concluded that the highly flexible transfersomal oral films (TOFs) effectively improved the bioavailability and antihistamine activity of EBT.

Evaluation of the Benefits of Microfluidic-Assisted Preparation of Polymeric Nanoparticles for DNA Delivery

An effective delivery vehicle of genetic materials to their target site is the key to a successful gene therapy. In many cases, nanoparticles are used as the vehicle of choice and the efficiency of the delivery relies heavily on the physicochemical properties of the nanoparticles. Microfluidics, although being a low throughput method, has been increasingly researched for the preparation of nanoparticles. A range of superior properties were claimed in the literature for microfluidic-prepared platforms, but no evidence on direct comparison of the properties of the nanoparticles prepared by microfluidics and conventional high throughput method exists, leaving the industry with little guidance on how to select effective large-scale nanoparticle manufacturing method. This study used plasmid DNA-loaded PLGA-Eudragit nanoparticles as the model system to critically compare the nanoparticles prepared by conventional and microfluidics-assisted nanoprecipitation. The PLGA-Eudragit nanoparticles prepared by microfluidics were found to be statistically significantly larger than the ones prepared by conventional nanoprecipitation. PLGA-Eudragit nanoparticle prepared conventionally showed higher DNA loading efficiency. Although the DNA-loaded nanoparticles prepared by both methods did not induce significant cytotoxicity, the transfection efficiency was found to be higher for the ones prepared conventionally which has good potential for plasmid delivery. This study for the first time provides a direct comparison of the DNA-loaded nanoparticles prepared by microfluidic and conventional methods. The findings bring new insights into critical evaluation of the selection of manufacturing methods of nanoparticles for future gene therapy.

Enhancing the Poor Flow and Tableting Problems of High Drug-Loading Formulation of Canagliflozin Using Continuous Green Granulation Process and Design-of-Experiment Approach

Maximization of drug-loading can significantly reduce the size of dosage form and consequently decrease the cost of manufacture. In this research, two challenges were addressed: poor flow and tableting problems of high-drug loading (>70%) formulation of canagliflozin (CNG), by adopting the moisture-activated dry granulation (MADG) process. In this method, heating and drying steps were omitted so, called green granulation process. A 3² full-factorial design was performed for optimization of key process variables, namely the granulation fluid level (X₁) and the wet massing time (X₂). Granulation of CNG was carried out in the presence of polyvinylpyrrolidone, and the prepared granules were compressed into tablets. Regression analysis demonstrated the significant (p ≤ 0.05) effect of X₁ and X₂ on properties of granules and corresponding tablets, with pronounced impact of X₁. Additionally, marked improvement of granules’ properties and tableting of CNG were observed. Furthermore, the optimized process conditions that produced good flow properties of granules and acceptable tablets were high level of granulation fluid (3.41% w/w) and short wet massing time (1.0 min). Finally, the MADG process gives the opportunity to ameliorate the poor flow and tableting problems of CNG with lower amounts of excipients, which are important for successful development of uniform dosage unit.

Impacts of particle size on the cytotoxicity, cellular internalization, pharmacokinetics and biodistribution of betulinic acid nanosuspensions in combined chemotherapy

To evaluate the effect of particle size on the cellular internalization, tissue distribution, and bioavailability of betulinic acid nanosuspensions (BA/NSs) and further investigate the combined effect of BA/NSs and Taxol® on breast cancer, BA/NSs with different particle sizes (160 nm, 400 nm, and 700 nm) were prepared by an efficient universal green technology. The use of BA/NS (160 nm) was more likely to increase the BA release rate and enhance bioavailability compared with the use of larger size particles. BA/NSs were internalized by 4T1 cells in different ways, including clathrin-mediated endocytosis, caveolae-mediated endocytosis, and macropinocytosis. For the 4T1 orthotopic tumor model, BA/NS (160 nm) showed a tendency to accumulate at a higher level in tumor tissue. Moreover, combination therapy with BA/NSs and Taxol® showed remarkable potential to enhance antitumor activity in vitro and in vivo. The cytotoxicity and apoptotic ability of the different preparations decreased in the following order: BA/NS (160 nm) + Taxol®, BA/NS (400 nm) + Taxol®, and BA/NS (700 nm) + Taxol®. The tumor inhibition rates of BA/NSs (160 nm, 400 nm, and 700 nm) combined with Taxol® were 2.35-, 1.74- and 1.12-fold higher than that of free BA, respectively. The combined chemotherapy showed good safety, indicating that it had the effect of enhancing treatment and reducing toxicity.

Hybridized nanoamorphous micellar dispersion using a QbD-DM3 linked rational product design strategy for ritonavir: A BCS IV drug

A QbD-DM³ linked rational product design strategy was adopted to create a hybridized ritonavir (RTV, BCS Class IV) nanoamorphous micellar dispersion (RTV-NAD). A DM³ research strategy was employed in conjunction with the quality-by-design spaces, and quality target product profile to link the critical material attributes and critical process parameters to the quality target product profile's critical product attributes QbD elements. A Box-Behnken design and multivariate analysis using multiple linear regression and partial least squares provided data analysis. The hybridized strategy leveraged three different mechanisms to increase RTV's solubility and four mechanisms to increase its dissolution rate. Statistically significant models were generated for critical product attributes: particle size (p = 0.0000, R² adjusted = 0.9513), polydispersity index (p = 0.0002, R² adjusted = 0.6398), zeta potential (p = 0.0000, R² adjusted = 0.9744), and drug loading on a dry basis (p = 0.0000, R² adjusted = 0.9951). The impact of drug concentration, Soluplus® concentration, and solvent:antisolvent ratio, their interactions and square effects on the critical product attributes were assessed by multivariate analysis. The QbD optimal formulation was determined for RTV-NAD. Multiple linear regression and partial least squares computational predictability was evaluated using three verification batches. The prediction error for critical product attributes was <5%. RTV-NAD and ritonavir microsuspension were characterized by x-ray diffraction and in-vitro dissolution studies. X-ray diffraction confirmed the amorphous nature of the RTV-NAD. RTV-NAD exhibited a 'spring-hover' dissolution profile at pH 4.5. At pH 6.8, a classic 'spring-parachute' dissolution behavior was observed.

Investigation of Formulation and Process Parameters of Wet Media Milling to Develop Etodolac Nanosuspensions

PURPOSE

Etodolac (ETD) is one of the non-steroidal anti-inflammatory drugs which has low aqueous solubility issues. The objective of this study was to develop ETD nanosuspensions to improve its poor aqueous solubility properties while investigating formulation and process parameters of wet media milling method via design of experiment (DoE) approach.

METHODS

The critical formulation parameters (CFP) were selected as ETD amount, stabilizer type and ratio as well as critical process parameters (CPP) which were bead size, milling time and milling speed. The two-factorial-2³ and The Box-Benkhen Designs were generated to evaluate CFP and CPP, respectively. Particle size (PS), polydispersity index (PDI) and zeta potential (ZP) were analyzed as dependent variables. Characterization, physical stability and solubility studies were performed.

RESULTS

Optimum nanosuspensions stabilized by PVP K30 and Poloxamer 188 showed 188.5 ± 1.6 and 279.3 ± 6.1 nm of PS, 0.161 ± 0.049 and 0.345 ± 0.007 PDI, 14.8 ± 0.3 and 16.5 ± 0.4 mV of ZP values, respectively. The thermal properties of ETD did not change after milling and lyophilization process regarding to DSC analysis. Also, the crystalline state of ETD was preserved. The morphology of particle was smooth and spherical on SEM. The dry-nanosuspensions stayed physically stable for six months at room temperature. The solubility of nanosuspensions increased up to 13.0-fold in comparison with micronized ETD.

CONCLUSIONS

In conclusion, it is found that the poor solubility issue of ETD can be solved by nanosuspension. DoE approach provided benefits such as reducing number of experiments, saving time and improving final product quality by using wet media milling.

Microfluidics for pharmaceutical nanoparticle fabrication: The truth and the myth

Using micro-sized channels to manipulate fluids is the essence of microfluidics which has wide applications from analytical chemistry to material science and cell biology research. Recently, using microfluidic-based devices for pharmaceutical research, in particular for the fabrication of micro- and nano-particles, has emerged as a new area of interest. The particles that can be prepared by microfluidic devices can range from micron size droplet-based emulsions to nano-sized drug loaded polymeric particles. Microfluidic technology poses unique advantages in terms of the high precision of the mixing regimes and control of fluids involved in formulation preparation. As a result of this, monodispersity of the particles prepared by microfluidics is often recognised as being a particularly advantageous feature in comparison to those prepared by conventional large-scale mixing methods. However, there is a range of practical drawbacks and challenges of using microfluidics as a direct micron- and nano-particle manufacturing method. Technological advances are still required before this type of processing can be translated for application by the pharmaceutical industry. This review focuses specifically on the application of microfluidics for pharmaceutical solid nanoparticle preparation and discusses the theoretical foundation of using the nanoprecipitation principle to generate particles and how this is translated into microfluidic design and operation.

Contribution of Crystal Lattice Energy on the Dissolution Behavior of Eutectic Solid Dispersions

In the literature, it is reported that eutectics lead to the enhanced dissolution of a poorly soluble compound. However, the solubility theory suggests that since crystal structures of two components are unchanged that all else being equal, the dissolution rates of a fused mixture (FM) should be the same as a physical mixture (PM). The influence of crystal lattice energy on dissolution profiles was investigated using the PM and FM. Experimental phase diagrams constructed using differential scanning calorimetry data were compared with those theoretically derived. Deviation of the experimental phase diagram curves from the theoretical model indicates the nonideal behavior of both systems (ibuprofen/poly(ethylene glycol)-6000 and acetaminophen/caffeine). Both the binary systems showed an increase in the dissolution rate of the PM and FM. However, the dissolution from the PM was comparable with the FM's dissolution profile. The theoretical solubility calculations using the modified solubility equation showed that the use of the eutectic temperature instead of the drug's melting point should give a 3-4-fold increase in drug solubility. However, the correlation between dissolution and solubility calculation showed that the FM did not improve the dissolution when compared with the respective PM's dissolution profile. The proposed explanation is that the unchanged crystal lattice energy in eutectics still limits the solubility and therefore the dissolution rate.

Development of Nanocrystal Ziprasidone Orally Disintegrating Tablets: Optimization by Using Design of Experiment and In Vitro Evaluation

The objective of the current study was to develop ziprasidone hydrochloride monohydrate (ZHM) nanocrystal-based orally dispersible tablet (ODT) formulations. Design of experiment approach was used to develop ODTs. The tablets were compressed using direct compression method and characterized with quality control tests. In vitro dissolution studies and Caco-2 cell permeability tests were executed. The hardness and friability values of nanocrystal-based ODTs were found 31.2 N and 1.05%, respectively. The disintegration time was below 10 s. Dissolution profile in pH 7.4 phosphate buffer showed that nanocrystal-based ODTs and commercial product were dissolved in 120 min 58.98% and 16%, respectively. In pH 7.4 phosphate buffer with SLS, sample groups dissolved above 85% at the end of the study. Permeability value and cumulative ZHM amount on the cells were improved with nanocrystals. In conclusion, the novel formulation of ZHM nanocrystal-based ODTs was successfully developed for alternative dosage form.

Development and evaluation of TPGS/PVA-based nanosuspension for enhancing dissolution and oral bioavailability of ticagrelor

In this study, we developed ticagrelor-dispersed nanosuspension (TCG-NSP) to enhance the dissolution and oral bioavailability of ticagrelor (TCG) through a statistical design approach. TCG, a reversible P2Y₁₂ receptor antagonist, is classified as a biopharmaceutics classification system (BCS) class IV drug with low solubility and permeability, resulting in low oral bioavailability. Nanosuspension (NSP) is an efficient pharmaceutical technique for overcoming the disadvantages. First, we optimized TCG-NSP consisting of D-α-Tocopherol polyethylene glycol 1000 succinate (TPGS) and polyvinyl alcohol (PVA), which exhibited homogeneously dispersed TCG particle (233 nm) and low precipitation (3%). Characterization studies demonstrated that TCG-NSP provided amorphous TCG particles and supersaturation effect, resulting in higher dissolution than a commercial product. In addition, everted gut sac and pharmacokinetic studies confirmed that TCG-NSP improved the gastrointestinal permeation of TCG by 2.8-fold compared to commercial product, thereby enhancing the oral bioavailability (2.2-fold). These results suggested that TCG-NSP could be successfully used as an efficient pharmaceutical formulation to achieve the enhanced dissolution and oral bioavailability of TCG.

Advanced modification of drug nanocrystals by using novel fabrication and downstream approaches for tailor-made drug delivery

Drug nanosuspensions/nanocrystals have been recognized as one useful and successful approach for drug delivery. Drug nanocrystals could be further decorated to possess extended functions (such as controlled release) and designed for special in vivo applications (such as drug tracking), which make best use of the advantages of drug nanocrystals. A lot of novel and advanced size reduction methods have been invented recently for special drug deliveries. In addition, some novel downstream processes have been combined with nanosuspensions, which have highly broadened its application areas (such as targeting) besides traditional routes. A large number of recent research publication regarding as nanocrystals focuses on above mentioned aspects, which have widely attracted attention. This review will focus on the recent development of nanocrystals and give an overview of regarding modification of nanocrystal by some new approaches for tailor-made drug delivery.

Enhancing Betulinic Acid Dissolution Rate and Improving Antitumor Activity via Nanosuspension Constructed by Anti-Solvent Technique

Purpose

The aim of this study was to prepare and evaluate betulinic acid nanosuspension (BA-NS) for new drug delivery to enhance its solubility and in vitro anti-tumor activity.

Methods

BA-NS was formulated by an anti-solvent precipitation method using the Box-Behnken design (BBD). Particle size (PS) and Zeta potential were measured by laser particle size analysis. The drug solid state after freeze drying was characterized by scanning electron microscope (SEM), transmission electron microscope (TEM), differential scanning calorimetry (DSC), X-ray powder diffraction (XRPD) and Fourier transform infrared spectroscopy (FTIR) after freeze drying. The saturation solubility and dissolution rate were determined by solubility assay and in vitro dissolution studies, respectively. The in vitro cytotoxicity assay was performed using 3-(4,5-dimethylthiazole)-2,5-diphenltetraazolium bromide (MTT) method.

Results

The PS was 129.7±12.2 nm having a Zeta potential of −28.1±4.5 mV and the polydispersity index (PDI) was 0.231±0.013, which confirmed that the nanosuspension was in the stable amorphous state. A series of characterization experiments demonstrated that nanoparticles retained original effective structure and existed as spherical or near-spherical nanoparticles in the nanosuspension, but the drug transferred from the crystal state to the amorphous state. The form of lyophilized BA-NS was very successful in enhancing the dissolution rate in PH-dependent way. The cytotoxicity assay revealed that BA-NS could significantly enhance the in vitro anti-proliferation against tumor cells compared to the BA suspension (BA-S).

Conclusion

The BA-NS can remarkably improve solubility and in vitro antitumor activity, which seems very promising for the treatment of cancers in practical application.