Enhanced ex vivo intestinal absorption of olmesartan medoxomil nanosuspension: Preparation by combinative technology

Fabrication of TPGS decorated Etravirine loaded lipidic nanocarriers as a neoteric oral bioavailability enhancer for lymphatic targeting

Etravirine (ERVN) is a potential NNRTI (non-nucleoside reverse transcriptase inhibitor) in treating HIV infection. It possesses extremely low oral bioavailability. The present research aims to optimize the formulation and characterization of TPGS-enriched ERVN-loaded lipid-based nanocarriers (NLCs) for HIV-infected patients. The formulation, ERVN-TPGS-NLCs, was optimized by central composite rotational design using a modified-solvent emulsification process. Various characterization parameters of NLCs were evaluated, including globule size of 121.56 ± 2.174 nm, PDI of 0.172 ± 0.042, the zeta potential of - 7.32 ± 0.021 mV, %EE of 94.42 ± 8.65% of ERVN and %DL was 8.94 ± 0.759% of ERVN and spherical shape was revealed by TEM. PXRD was also performed to identify the crystallinity of the sample. In-vitro drug release showed % a cumulative drug release of 83.72 ± 8.35% at pH 1.2 and 90.61 ± 9.11% at pH 6.8, respectively, whereas the % cumulative drug release from drug suspension (ERVN-S) was found to be 21.13 ± 2.01% at pH 1.2 and 24.84 ± 2.51 at pH 6.8 at the end of 48 h. Further, the intestinal permeation study and confocal microscope showed approximately three-fold and  two-fold increased permeation in ERVN-TPGS-NLCs and ERVN-NLCs across the gut sac compared to ERVN-S. Hemolysis compatibility and lipolysis studies were performed to predict the in-vivo fate of the formulation. The pharmacokinetic study revealed a 3.13-fold increment in the relative bioavailability, which agrees with the ex-vivo studies, and lymphatic uptake was validated by using cycloheximide along with designed formulation, which showed the impact of lymphatic uptake in AUC. This study ensures that ERVN-TPGS-NLCs take lymphatic uptake to minimize the first-pass metabolism followed by improved oral bioavailability of ERVN. Thus, the enhanced bioavailability of ERVN can reduce the high dose of ERVN to minimize the adverse effects related to dose-related burden.

Improving intestinal absorption and antibacterial effect of florfenicol via nanocrystallisation technology

To study the effects of nanocrystallisation technology on the intestinal absorption properties and antibacterial activity of florfenicol (FF). The florfenicol nanocrystals (FF-NC) were prepared by wet grinding and spray drying. Additionally, changes in particle size, charge, morphology, and dissolution of FF-NC in the long-term stability were monitored by laser particle sizer, TEM, SEM, paddle method, and the structure of FF-NC powder was characterised by nuclear magnetic resonance (NMR) test. The antibacterial activity, intestinal absorption and intestinal histocompatibility of FF-NC were investigated by the stiletto, mini broth dilution susceptibility test, in situ single-pass intestinal perfusion (SPIP) and haematoxylin-eosin (H-E) staining. After 12 months of storage, the particle size and zeta potential of FF-NC were 280.43 ± 8.21 nm and -19.64 ± 3.45 mV, and the electron microscopy results showed that FF-NC were nearly circular with no adhesion between particles. In addition, the drug loading, encapsulation efficiency, and dissolution of FF-NC did not change significantly during storage. The inhibition zone of FF-NC against Escherichia coli and Staphylococcus aureus was 21.37 ± 1.70 mm and 25.17 ± 2.47 mm, respectively. Compared with the FF, the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of FF-NC are reduced, and the absorption rate constant (K_a) and efficient permeability coefficient (P_eff) of FF-NC in the three intestinal segments were increased by 1.28, 0.25, and 9.10 times and 0.59, 0.17, and 6.0 times, respectively. The results of tissue sections showed that FF-NC had little damage to the small intestinal. Nanocrystallisation technology is an effective method to increase the intestinal absorption and antibacterial activity of FF.

Pharmacokinetics and Anti-Diabetic Studies of Gliclazide Nanosuspension

Gliclazide (GCZ), an antidiabetic medication, has poor solubility and limited oral bioavailability due to substantial first-pass metabolism. Thus, the purpose of the current study was to optimize and formulate a GCZ nanosuspension (NS) employing the antisolvent precipitation technique. A three-factor, three-level Box–Behnken design (BBD) was used to examine the impact of the primary formulation factors (drug concentration, stabilizer, and surfactant %) on particle size. The optimized NS contains 29.6 mg/mL drug, 0.739% lecithin, and 0.216% sodium dodecyl sulfate (SDS). Under scanning microscopy, the topography of NS revealed spherical particles. Furthermore, NS had a much better saturation solubility than the pure material, which resulted in a rapid dissolving rate, which was attributed to the amorphous structure and smaller particle size of the NS particles. Studies on intestinal permeability using the in vitro noneverted intestinal sac gut method (duodenum, jejunum, and ileum) and single-pass intestinal permeability (SPIP) techniques showed that the effective permeability was also increased by more than 3 fold. In the pharmacokinetic study, the C_max and AUC_0–t values of NS were approximately 3.35- and 1.9-fold higher than those of the raw medication and marketed formulation (MF). When compared to plain drug and commercial formulations, the antidiabetic efficacy of NS demonstrated that it had a significant impact on lowering glucose levels.

Lipid-Polymer Hybrid Nanocarriers for Oral Delivery of Felodipine: Formulation, Characterization and Ex Vivo Evaluation

Purpose: Felodipine, is a calcium-channel antagonist used for hypertension and angina pectoris. It is practically insoluble in aqueous media and shows low oral bioavailability (15%-20%). This investigation aims to prepare and characterize oral felodipine lipid-polymer hybrid nanocarriers (LPHNs) to increase solubility and control delivery for increasing bioavailability and enhance patient compliance. Methods: The newly microwave-based method was prepared with felodipine LPHNs (H1-H35) successfully. The (H1-H35) were subjected to thermodynamic stability experiments. After that, select nine felodipine LPHNs (F1-F9) that have smart physical stability for further optimization of different characterization processes. Results: The felodipine LPHNs (F4) are considered the most optimized formula. It was characterized by lower particle size (33.3 nm), lower PDI (0.314), high zeta potential (13.6 mV), entrapment efficiency is (81.645% w/w), drug loading is (16.329% w/w), the pH value is 4, excellent percent of light transmittance (95.5%), pseudoplastic rheogram, significantly high (P < 0.05) dissolution rate with sustained drug delivery and success ex-vivo intestinal permeation attributes. The (F4) subject for further investigations of Fourier transformed infrared spectroscopy (FTIR), atomic force microscopy (AFM), and transmission electron microscopy (TEM). The results of FTIR, AFM, and TEM indicate there is no interaction between the felodipine and excipients and that the particulate system in the nanoscale dispersion system confirms the high stability. Conclusion: The optimized felodipine LPHNs (F1-F9) formulations were smart formulations for sustained oral delivery of felodipine and that F4 was the most optimized formula according to its characterization processes.

Combinatorial delivery of Ribociclib and Green tea extract mediated nanostructured lipid carrier for oral delivery for the treatment of breast cancer synchronizing in silico, in vitro, and in vivo studies

Purpose: The current research investigated the development and evaluation of dual drug-loaded nanostructure lipidic carriers (NLCs) of green tea extract and Ribociclib.Method: In silico study were performed to determine the effectiveness of combinational approach. The prepared NLCs were subjected to in vitro drug release, lipolysis, haemolysis and cell line studies to assess their in vivo prospect.Results: In silico study was done to get docking score of EGCG (-8.98) close to Ribociclib (-10.78) in CDK-4 receptors. The prepared NLCs exhibited particle size (175.80 ± 3.51 nm); PDI (0.571 ± 0.012); and %EE [RBO (80.91 ± 1.66%) and GTE 75.98 ± 2.35%)] respectively. MCF-7 cell lines were used to evaluate the MTT assay, cellular uptake and antioxidant (ROS and SOD) of prepared NLCs. In vitro drug release showed the controlled release up to 72 h. In vitro lipolysis and in vitro haemolysis studies showed the availability of drugs at absorption sites and the greater in vivo prospects of NLCs respectively. Pharmacokinetic study revealed a 3.63-fold and 1.53-fold increment in RBO and GTE bioavailability in female Wistar rats respectively.Conclusion: The prominent potential of green tea extract and RBO-loaded NLCs in enhancing their therapeutic efficacy for better treatment of breast cancer.

Nose to brain delivery of nanosuspensions with first line antiviral agents is alternative treatment option to Neuro-AIDS treatment

Intranasal drug delivery is one of the uprising areas of the research in targeting drug to the brain. Nose to brain drug delivery follows the olfactory pathway and purportedly known to be more efficient to deliver neuro-therapeutics to the brain by circumventing the BBB and thereby increasing bioavailability of drugs in the brain. The advantage of this method is non-invasiveness, rapid onset of action and helps to achieve site specific delivery. In this research work nanosuspension were prepared using combination of antiretroviral agents for Neuro-AIDS treatment. Nanosuspensions were prepared by high-speed homogenization, wet milling and high-pressure homogenization techniques. Formulations were analysed by SEM, FTIR, and DSC. Morphology and stability analysis was done by analysing zeta potential, particle size, and PDI. Ex-vivo diffusion study and histopathological analysis was performed using goat nasal mucosa. High pressure homogenization was found to be best technique for formulation of nanosuspension. Antiviral drugs could be delivered successfully by optimizing nasal dosage form.

Preparation and characterization of nanocochelate by using phosphatidylcholine as lipid carrier for enhancement of permeability and bioavailability of rosuvastatin

OBJECTIVE

Rosuvastatin (ROS) is a class of antihyperlipidemic agents belonging to the class of statins with poor permeability, which results in low oral bioavailability, i.e. 20%. The objective of the present study was to improve the permeability and bioavailability of ROS by developing nanocochelates using naturally biocompatible phosphatidylcholine, a type of lipid which is used as Ca ²⁺ cations for the calcification process.

SIGNIFICANCE

For the loaded ROS, the trapping method was used to build nanocochelates to boost the intestinal permeability of phosphatidylcholine and divalent choline is a calcium chloride cationic solution.

METHODS

Nine different formulations have been produced and with varying lipid and cationic solution concentrations. The formulation of nanocochelates characterized by scanning electron microscopy, particle size, and zeta potential. Permeability studies have been conducted to determine the permeability improvement property of nanocochelates. The pharmacokinetic study was performed in Wistar albino rats to determine the bioavailability enhancement potential of nanocochlelates.

RESULTS

The concentration of optimum lipid, calcium chloride was found to be 80 mg, 200 ul respectively which improve permeability by 3.44 times as compared to the marketed formulation. The in-vitro drug release over a prolonged period i.e.12 hours. Which was substantially better than the traditional formulation of tablets. Nearly five fold enhancement in bioavailability was observed in case of optimized formulation as compared to the marketed formulation (p < 0.05).

CONCLUSION

The findings suggest that the use of natural lipid carrier by nanocochelates of Rosuvastatin was promising the oral delivery approach.

Nanostructured lipid carriers of isradipine for effective management of hypertension and isoproterenol induced myocardial infarction

The objective of the present paper is to formulate nanostructured lipid carriers (NLCs) of a calcium channel blocker, isradipine, to enhance its oral bioavailability and prolong its antihypertensive effect apart from evaluating efficacy of the formulation in isoproterenol induced myocardial infarction in rats. Formulation was optimized using quality by design (QbD)-based approach. Three factors i.e., total lipid concentration (%), homogenization pressure (bar), and number of cycles were optimized through Box-Behnken design to estimate their effect on critical quality attributes (CQAs) viz., size (nm), % entrapment efficiency, and in vitro % drug release which were found to be 80.9 ± 1.7 nm, 83.51 ± 2.15%, and 83.3 ± 3.86% after 24 h, respectively. In vivo pharmacokinetic study indicated 4.207 and 1.907 times increase in the oral bioavailability of optimized nanostructured lipid carrier without and with cycloheximide (lymphatic transport inhibitor), respectively. Treatment with ISO (isoproterenol) significantly diverges the levels of antioxidant marker, TBARS (thiobarbituric acid), and ultrastructure of the cardiac tissue indicating significant myocardial damage. Pretreatment of nanostructured lipid carrier of isradipine (ISD-NLCs) significantly prevented the antioxidant status and ultrastructural changes in the heart. In conclusion, this study confirms that optimized NLCs can substantially improve oral bioavailability of isradipine and presents a promising strategy in the management of hypertension for longer duration of time apart from demonstrating its preclinical efficacy in cardioprotection.

Ribociclib Nanostructured Lipid Carrier Aimed for Breast Cancer: Formulation Optimization, Attenuating In Vitro Specification, and In Vivo Scrutinization

Purpose

The current investigation is on the explicit development and evaluation of nanostructured lipidic carriers (NLCs) through the oral route to overcome the inherent lacuna of chemotherapeutic drug, in which Ribociclib (RBO) was used for breast cancer to diminish the bioavailability issue.

Method

The RBO-NLCs were prepared using the solvent evaporation method and optimized method by the Box–Behnken design (BBD). Various assessment parameters characterized the optimized formulation and their in vivo study.

Results

The prepared NLCs exhibited mean particle size of 114.23 ± 2.75 nm, mean polydispersity index of 0.649 ± 0.043, and high entrapment efficiency of 87.7 ± 1.79%. The structural analysis by TEM revealed the spherical size of NLCs and uniform drug distribution. An in vitro drug release study was established through the 0.1 N HCl pH 1.2, acetate buffer pH 4.5, and phosphate buffer pH 6.8 with % cumulative drug release of 86.71 ± 8.14, 85.82 ± 4.58, and 70.98 ± 5.69%, was found respectively, compared with the RBO suspension (RBO-SUS). In vitro intestinal gut permeation studies unveiled a 1.95-fold gain in gut permeation by RBO-NLCs compared with RBO-SUS. In vitro lipolysis suggests the drug availability at the absorption site. In vitro haemolysis study suggests the compatibility of NLCs to red blood cells compared to the suspension of the pure drug. The confocal study revealed the depth of penetration of the drug into the intestine by RBO-NLCs which was enhanced compared to RBO-SUS. A cell line study was done in MCF-7 and significantly reduced the IC₅₀ value compared to the pure drug. The in vivo parameters suggested the enhanced bioavailability by 3.54 times of RBO-NLCs as compared to RBO-SUS.

Conclusion

The in vitro, ex vivo, and in vivo results showed a prominent potential for bioavailability enhancement of RBO and effective breast cancer therapy.

A new nanosuspension prepared with wet milling method for oral delivery of highly variable drug Cyclosporine A: Development, optimization and in vivo evaluation

Cyclosporine A (CsA) is a cyclic polypeptide, that has been widely used for immunosuppression. This study aims to develop nanosuspension for oral administration of CsA using the wet milling (WM) method one of the top-down technologies. The WM method was optimized by studying the effects of critical process parameters for WM on the particle size (PS), particle size distribution (PDI), and zeta potential (ZP) of nanosuspensions using the Design of Experiment (DoE) approach. Nanosuspension was developed using hydroxypropyl methylcellulose (HPMC) and sodium dodecyl sulfate (SDS) and in vitro characterization studies were performed. In vitro dissolution and in vivo pharmacokinetic studies were conducted with biorelevant media (fasted and fed state simulated fluids) and fasted and fed states in rats, respectively. In vivo immunological studies were also performed. PS, PDI, and ZP values for nanosuspension were approximately 600 nm, 0.4, -25 mV, respectively. The solubility of CsA was increased by 4.5-folds by nanosuspensions. Dissolution studies showed that nanosuspension had higher dissolution than the commercial product in the FeSSIF medium. The pharmacokinetic study indicated that AUC_0-24 values of CsA nanosuspension were to be 2.09 and 5.51-fold higher than coarse powder in fasted and fed conditions, respectively. Immunological studies were carried out after oral administration of nanosuspension for 21 days, the ratio of CD4+/CD8+ was found to be more acceptable than the commercial product. These results demonstrated that nanosuspension is a promising approach for increasing the bioavailability and avoiding the food effect on absorption of CsA which one of the highly variable drugs.

Development of cyclosporine A nanosuspension: cytotoxicity and permeability on Caco-2 cell lines

Cyclosporine A is a calcineurin inhibitor and is usually used as an immunosuppressant medication. The main purpose of this study is to develop nanosuspension of polypeptide cyclosporine A by using the wet milling method for oral administration. Cell culture studies were also performed with human intestinal Caco-2 cell lines. Hydroxypropyl methylcellulose and sodium dodecyl sulfate were used as stabilizers in nanosuspension. In vitro characterization studies such as Fourier-transform infrared analysis and morphological imaging with scanning electron microscopy have been carried out with obtained cyclosporine A nanosuspension. The particle size, particle size distribution, and zeta potential values of the nanosuspension were measured approximately 400 nm, 0.4, and -25 mV, respectively. The solubility of cyclosporine A was increased 4.5 times in nanosuspension compared to the coarse cyclosporine A powder. As a result of cytotoxicity studies conducted with different concentrations, it was decided to conduct permeability studies at a dose equivalent to 150 µg/mL cyclosporine A. Permeation studies have shown that the nanosuspension increases cyclosporine A transport by 5 and 1.5 times, respectively, compared to coarse powder and commercial product.

Rutin nanosuspension for potential management of osteoporosis: effect of particle size reduction on oral bioavailability, in vitro and in vivo activity

Clinical significance of Rutin (RUT) is limited by poor dissolution rate and low oral bioavailability. The study was designed to improve the physicochemical and therapeutic potential of the drug by formulating nanosuspension (NS) for osteoporosis. Rutin nanosuspension (RUT-NS) was prepared after screening a range of stabilizers and their combinations at a different concentration by antisolvent precipitation technique. Effect of precipitation on crystallinity (differential scanning calorimetry DSC, X-ray diffraction studies XRD), morphology (scanning electron microscopy, SEM) and chemical interaction (attenuated total reflectance fourier-transform infrared spectroscopy ATR-FTIR) were studied through biophysical techniques. An optimized nanosuspension exhibited a minimum particle size of 122.85 ± 5.02 nm with higher dissolution of RUT-NS (87. 63 ± 2.29%) as compared to pure drug (39.77 ± 2.8 6%). The enhanced intestine absorption and apparent permeability were achieved due to the improved particle size, surface area and dissolution. RUT-NS displayed greater (3 folds) AUC_0-24 h than pure drug. In vitro assays with RUT-NS depicted an increased cell proliferation, antioxidant (ROS) activity and osteocalcin production in MG-63 osteoblast cells. The augmented biochemical in vivo biomarkers and bone quality proved the protective effect of RUT-NS. The results supported RUT-NS as a potential therapy for maintaining bone health.

Development of Darunavir proliposome powder for oral delivery by using Box-Bhenken design

The aim of this study is to develop Darunavir (DRV) proliposome powder for oral delivery. Darunavir-loaded oral proliposome powder (OPP) was prepared by a solvent evaporation technique with varying independent variables at three different levels. Based on different levels, proliposome powder formulation was optimized by using Box-Behnken design. The formulations were analyzed for its size distribution, entrapment efficiency, and surface morphology. Optimized proliposome batch A was evaluated for physical parameter, morphological parameters, entrapment efficiency, followed by in vitro, ex vivo, and in vivo studies. Oral proliposome powder showed good micromeritic properties with angle of repose was less than 30°, Carr's index and Hausner's ratio were also less than 21 and 1.25, respectively. The mean size of the vesicles was in the range of 180-290 nm. The assay and entrapment efficiency of pro-liposome powder formulations were 79.00 ± 0.2 and 93.46 ± 0.2%, respectively. In vitro release of DRV proliposome powder was 78.17 ± 0.1% after 24 h which shows good release from the vesicle of proliposome. Ex vivo permeation study shows 58.11% enhancement which shows good permeation. The optimize batch A of proliposome powder indicated 50% enhancement in the relative bioavailability as compared to the DRV suspension. The results showed that proliposome powder containing DRV can efficiently deliver in to the blood stream. This drug delivery system has been designed as a novel platform for potential oral delivery of drugs having poor water solubility and high first-pass metabolism.

Study of Top-down and Bottom-up Approaches by Using Design of Experiment (DoE) to Produce Meloxicam Nanocrystal Capsules

In order to investigate the correlation among energy input-related, drug-related, and stabilizer-related aspects for both top-down and bottom-up nanocrystal production, meloxicam nanosuspensions (NS) were produced by using three different methods (low-energy wet milling, high-pressure homogenization, and precipitation) and each method was optimized by using design of experiment (DoE). Box-Behnken design of 3 factors and 3 levels was applied for the optimization of each method. All the three models were found to be significant and the optimized process parameters were used for production of NS, respectively. Interestingly, by comparison of the top-down and bottom-up approaches, the influence of energy input (homogenization pressure or milling speed) from the instruments seemed not significant for top-down compared with bottom-up for this drug. Different mechanisms of homogenization (relatively high energy zone) and milling (relatively low energy zone) led to obtained various significant correlations for each method. Capsules containing nanocrystals were successfully produced by using a novel method applying NS (after wet bead milling and homogenization processes) as wetting agent for direct capsuling and showed superiority regarding as dissolution rate compared with the traditional two-step method (freeze-dried powder used for capsuling as the first step). Different NS preparation methodologies proved to have a direct influence on the following capsuling process and consequently, in the dissolution rate. This study also proved that residual DMSO in nanosuspension after precipitation process could affect the freeze-drying process, which might further alter the redispersion and influence the downstream processes.

Omega-3 Fatty Acid Based Nanolipid Formulation of Atorvastatin for Treating Hyperlipidemia

Purpose: In the current study, attempts have been made to formulate an omega-3 fatty acid based nanostructured lipid carriers of atorvastatin (AT), for treating hyperlipidemia; and to evaluate their antihyperlipidemic activity using in vitro and in vivo studies. Methods: Omega-3 fatty acid based AT-loaded nanolipid carriers (NLC) were formulated by the melt emulsification ultrasonication technology. The prepared NLC consist of stearic acid (as solid lipid), omega-3 fatty acid (as liquid lipid), Tween 80, poloxamer 188 (surfactants) and soya-lecithin (co-surfactant). Results: AT loaded NLCs have a particle size of 74.76 ± 4.266 nm, a zeta potential value of -36.03 ± 1.504 mV and a high drug entrapment efficiency (EE) of 86.70 % ± 0.155. The release of AT from NLCs exhibited a sustained behaviour, which made it an ideal vehicle for drug delivery. MTT assay results indicated that NLCs are compatible with L929 (mouse fibroblast) cell lines. Anti-hyperlipidemic study showed a significant reduction in LDL and TG levels in serum with the orally administered Omega-3 fatty acid based AT loaded NLCs when compared to marketed formulation. Conclusion: The results demonstrated that the omega-3 fatty acid based NLC has the potential to be a promising nanomedicine for the treatment of hyperlipidemia.

Fabrication of Nanosuspension Directly Loaded Fast-Dissolving Films for Enhanced Oral Bioavailability of Olmesartan Medoxomil: In Vitro Characterization and Pharmacokinetic Evaluation in Healthy Human Volunteers

Olmesartan medoxomil (OM) is an antihypertensive drug with poor water solubility and low oral bioavailability (28.6%). Accordingly, this study aimed to formulate and evaluate OM nanosuspension incorporated into oral fast-dissolving films (FDFs) for bioavailability enhancement. OM nanosuspension was prepared by antisolvent-precipitation-ultrasonication method and characterized regarding particle size (122.67 ± 5.03 nm), span value (1.40 ± 0.51), and zeta potential (- 46.56 ± 1.20 mV). Transmission electron microscopy (TEM) of the nanosuspension showed spherical non-aggregating nanoparticles. The nanosuspension was then directly loaded into FDFs by solvent casting technique. A full factorial design (2² × 3¹) was implemented for optimization of the FDFs using Design-Expert® software. Physical and mechanical characteristics in addition to dissolution profiles of the FDFs were investigated. The optimum formula (FDF1) showed 0.43 ± 0.02 kg/mm² tensile strength, 20.50 ± 2.12 s disintegration time, and 87.53 ± 2.50 and 95.99 ± 0.25% OM dissolved after 6 and 10 min, respectively. Accelerated and long-term shelf stability studies confirmed the stability of FDF1. More than 75% OM was dissolved within 10 min from FDF1 compared with 9.80 and 47.80% for films prepared using coarse drug powder and market tablet, respectively. Relative bioavailability of FDF1 compared to market tablet was assessed in healthy human volunteers. The C_max value increased significantly from 66.62 ± 14.95 to 179.28 ± 23.96 ng/mL for market tablet and FDF1, respectively. Similarly, the AUC_0-72 value significantly increased from 498.36 ± 217.46 to 1083.67 ± 246.32 ng h/mL for market tablet and FDF1, respectively. Relative bioavailability of FDF1 was 209.28%. The highlighted results verified the effectiveness of OM nanosuspension-loaded FDFs in improving OM bioavailability.

Formulation and Evaluation of Naringenin Nanosuspensions for Bioavailability Enhancement

The clinical potential of naringenin (NRG) is compromised due to its poor aqueous solubility and low oral bioavailability. The study is aimed at addressing these issues by means of naringenin nanosuspensions (NRG-NS) formulated using polyvinylpyrrolidone (PVP K-90) as stabiliser via antisolvent sonoprecipitation method. Optimisation of sonication time, drug concentration and stabilisers was done based on particle size. Characterisation of pure NRG and NRG-NS was carried out by scanning electron microscopy, differential scanning calorimetry (DSC), x-ray powder diffractometry (XRD) and Fourier transform infrared spectroscopy (FTIR). In vitro dissolution, intestinal absorption by non-everted rat intestinal sac model and in situ single pass intestinal perfusion techniques were performed for further investigation. Nanosuspensions prepared using PVP K-90 lead to minimum particle size (117 ± 5 nm) with zeta potential of -14.6 ± 5.6 mV. The particle size was affected by increasing sonication time, concentration of stabiliser and drug. Nanosizing process converted the crystalline drug into amorphous form as predicted from DSC and XRD patterns. FTIR demonstrated the formation of hydrogen bonds between drug and polymer. NRG-NS displayed a higher dissolution amount (91 ± 4.4% during 60 min) compared to NRG powder (42 ± 0.41%). The apparent and effective permeability of NRG-NS was increased as compared to the pure NRG. The in vivo pharmacokinetics demonstrated that the C _max and AUC_0-24 h values of NRG-NS were approximately 2- and 1.8-fold superior than the pure drug. Hence, overall results confirmed nanosuspensions as promising approach for NRG delivery with high absorption in gastrointestinal tract, improved dissolution and oral bioavailability.

Formulation, optimization, and in vitro-in vivo evaluation of olmesartan medoxomil nanocrystals

The aim of the present study is to increase the saturation solubility and oral bioavailability of olmesartan medoxomil (OLM) using nano-sized crystals produced using a combination of antisolvent precipitation and high-shear homogenization. A response surface design comprising 46 runs was used to optimize the OLM nanocrystal formulation. The optimized formulation was produced using a combination of D-alpha tocopheryl polyethylene glycol 1000 succinate (TPGS) (0.7% w/v), Pluronic F-68® (0.5% w/v), and drug concentration (0.2% w/v) and subjected to 10 and 15 homogenization cycles at 1000 and 1700 bar, respectively. The particle size, polydispersity index (PDI), and zeta potential of optimized formulation were found to be 140 ± 10.34 nm, 0.07 ± 0.016, and -21.43 ± 2.33 mV, respectively. The optimized formulation exhibited irregular morphology as evaluated by scanning electron microscopy and was crystalline as determined by thermal analysis and powder X-ray diffraction studies. OLM nanocrystals showed a marked increase in the saturation solubility as well as rapid dissolution rate in comparison with the pure drug. No significant change in the particle size, PDI, and zeta potential was observed when optimized formulation was stored at room and refrigeration conditions for 3 months. Lastly, in vivo pharmacokinetic studies in Sprague-Dawley rats substantiate the ability of OLM nanocrystal formulation to significantly improve (∼4.6-fold) the oral bioavailability of OLM in comparison with the free drug. This study has established a potential and commercial viable OLM formulation with enhanced saturation solubility and in vivo oral bioavailability.

Nanosystem trends in drug delivery using quality-by-design concept

Quality by design (QbD) has become an inevitable trend because of its benefits for product quality and process understanding. Trials have been conducted using QbD in nanosystems' optimization. This paper reviews the application of QbD for processing nanosystems and summarizes the application procedure. It provides prospective guidelines for future investigations that apply QbD to nanosystem manufacturing processes. Employing the QbD concept in this way is a novel area in nanosystem quality.

A recent trend of drug-nanoparticles in suspension for the application in drug delivery

Persistent development in nanomedicine has enabled successful nanosizing of most drug samples which, in turn, imparts remarkable properties to the drugs such as enhanced solubility and bioavailability for the applications in drug delivery. In this context, several review articles are available in scientific domain covering inorganic nanoparticles such as Au, Ag, SPIONs, Qdots, carbon nanotubes and graphene; however, this review covers the development of drug nanoparticles together with their possibilities and limitation from fabrication (bottom up vs top down) to application in drug delivery during the last 5 years. In addition, some distinguished studies and novel drug particles are presented in order to contribute significantly toward the understanding of drug nanocrystals and its use in drug delivery.

Scale-up from batch to flow-through wet milling process for injectable depot formulation

Injectable depot formulations are aimed at providing long-term sustained release of a drug into systemic circulation, thus reducing plasma level fluctuations and improving patient compliance. The particle size distribution of the formulation in the form of suspension is a key parameter that controls the release rate. In this work, the process of wet stirred media milling (ball milling) of a poorly water-soluble substance has been investigated with two main aims: (i) to determine the parametric sensitivity of milling kinetics; and (ii) to develop scale-up methodology for process transfer from batch to flow-through arrangement. Ball milling experiments were performed in two types of ball mills, a batch mill with a 30ml maximum working volume, and a flow-through mill with a 250ml maximum working volume. Milling parameters were investigated in detail by methodologies of QbD to map the parametric space. Specifically, the effects of ball size, ball fill level, and rpm on the particle breakage kinetics were systematically investigated at both mills, with an additional parameter (flow-rate) in the case of the flow-through mill. The breakage rate was found to follow power-law kinetics with respect to dimensionless time, with an asymptotic d₅₀ particle size in the range of 200-300nm. In the case of the flow-through mill, the number of theoretical passes through the mill was found to be an important scale-up parameter.