Hot melt extrusion processing parameters optimization

© 2020 by the authors. Licensee MDPI, Basel, Switzerland. The aim of this study was to demonstrate the impact of processing parameters of the hot-melt extrusion (HME) on the pharmaceutical formulation properties. Carbamazepine (CBZ) was selected as a model water-insoluble drug. It was incorporated into Soluplus®, which was used as the polymeric carrier, to produce a solid dispersion model system. The following HME-independent parameters were investigated at different levels: extrusion temperature, screw speed and screw configuration. Design of experiment (DOE) concept was applied to find the most significant factor with minimum numbers of experimental runs. A full two-level factorial design was applied to assess the main effects, parameter interactions and total error. The extrudates’ CBZ content and the in vitro dissolution rate were selected as response variables. Material properties, including melting point, glass transition, and thermal stability, and polymorphs changes were used to set the processing range. In addition, the extruder torque and pressure were used to find the simplest DOE model. Each change of the parameter showed a unique pattern of dissolution profile, indicating that processing parameters have an influence on formulation properties. A simple, novel and two-level factorial design was able to evaluate each parameter effect and find the optimized formulation. Screw configuration and extrusion temperature were the most affecting parameters in this study

Design of Olmesartan Medoxomil-Loaded Nanosponges for Hypertension and Lung Cancer Treatments

Olmesartan medoxomil (OLM) is one of the prominent antihypertensive drug that suffers from low aqueous solubility and dissolution rate leading to its low bioavailability. To improve the oral bioavailability of OLM, a delivery system based on ethylcellulose (EC, a biobased polymer) nanosponges (NSs) was developed and evaluated for cytotoxicity against the A549 lung cell lines and antihypertensive potential in a rat model. Four OLM-loaded NSs (ONS1-ONS4) were prepared and fully evaluated in terms of physicochemical properties. Among these formulations, ONS4 was regarded as the optimized formulation with particle size (487 nm), PDI (0.386), zeta potential (ζP = −18.1 mV), entrapment efficiency (EE = 91.2%) and drug loading (DL = 0.88%). In addition, a nanosized porous morphology was detected for this optimized system with NS surface area of about 63.512 m2/g, pore volume and pore radius Dv(r) of 0.149 cc/g and 15.274 Å, respectively, measured by nitrogen adsorption/desorption analysis. The observed morphology plus sustained release rate of OLM caused that the optimized formulation showed higher cytotoxicity against A549 lung cell lines in comparison to the pure OLM. Finally, this system (ONS4) reduced the systolic blood pressure (SBP) significantly (p < 0.01) as compared to control and pure OLM drug in spontaneously hypertensive rats. Overall, this study provides a scientific basis for future studies on the encapsulation efficiency of NSs as promising drug carriers for overcoming pharmacokinetic limitations

Tailoring of Novel Bile Salt Stabilized Vesicles for Enhanced Transdermal Delivery of Simvastatin: A New Therapeutic Approach against Inflammation

Simvastatin (SMV), a cholesterol-lowering agent, has antioxidant and anti-inflammatory effects. Nevertheless, the oral use of SMV is linked with poor systemic bioavailability owing to its limited aqueous solubility and extensive first-pass metabolism. The aim of this study was to evaluate the feasibility of transdermal delivery of SMV using bile salt stabilized vesicles (bilosomes) for enhancing the anti-inflammatory potential of SMV. SMV-loaded bilosomes (SMV-BS) were prepared by the thin film hydration technique and optimized by 33 Box–Behnken design. The fabricated SMV-BS were assessed for vesicle size, entrapment efficiency (% EE) and cumulative drug release. The optimized formula was incorporated into HPMC gel and investigated for physical properties, ex vivo permeation, in vivo pharmacokinetic study and anti-inflammatory potential in inflamed paw edema rat model. The optimized SMV-BS showed vesicle size of 172.1 ± 8.1 nm and % EE of 89.2 ± 1.8%. In addition, encapsulating SMV within bilosomal vesicles remarkably sustained drug release over 12 h, compared to plain drug suspension. Furthermore, SMV-loaded bilosomal gel showed a three-fold enhancement in SMV transdermal flux, compared to plain drug suspension. Most importantly, the relative bioavailability of SMV-BS gel was ~2-fold and ~3-fold higher than those of oral SMV suspension and SMV gel, respectively. In carrageenan-induced paw edema model, SMV-BS gel induced a potent anti-inflammatory effect, as evidenced by a remarkable reduction in paw edema, which was comparable to that of the standard anti-inflammatory drug, indomethacin. Collectively, bilosomes might represent a plausible transdermal drug delivery system that could enhance the anti-inflammatory activity of SMV by boosting its skin permeation and its systemic bioavailability

Development and Characterization of Sustained-Released Donepezil Hydrochloride Solid Dispersions Using Hot Melt Extrusion Technology

The aim of this work was to develop the sustained release formulation of donepezil hydrochloride (DH) using the hot-melt extruded solid dispersion technique via the rational screening of hydrophobic carriers. Hydrophobic carriers with different physicochemical properties such as pH-independent swellability, low-permeability (Eudragit® RS PO (E-RS)), pH-independent non-swellability (ethyl cellulose N7 (EC-N7)), and the presence of lipids (Compritol® 888 ATO (C-888)) with or without pore-forming agents were used to achieve the sustained release profile of DH. Mannitol (MNT) was chosen as the temporary pore-forming agent. The thermal analysis showed that both the drug and C-888 preserved their crystallinity within a solid dispersion. During a dissolution test, MNT could generate pores, and the drug release rate was proportionally correlated to the MNT content. Tailoring of the ratio of C-888 and MNT in the formulations along with an appropriate extrusion temperature profile resulted in the modified release of DH, and a preferable release pattern was obtained under these conditions. C-888 was chosen for the further investigations to obtain tablets with a high integrity. The optimized tablets were compared to the marketed formulation of Aricept® in terms of drug release profiles. The optimized formulation showed the stable and sustained release behavior of extended release profile, which was close to the release behavior of Aricept® with good tablet characteristics. It was concluded that the hot-melt extrusion technique can be utilized for the manufacturing of DH sustained release tablets with improved tablet integrity and characteristics by co-processing the tablet excipient with DH/C-888

Development and Characterization of Sustained-Released Donepezil Hydrochloride Solid Dispersions Using Hot Melt Extrusion Technology

The aim of this work was to develop the sustained release formulation of donepezil hydrochloride (DH) using the hot-melt extruded solid dispersion technique via the rational screening of hydrophobic carriers. Hydrophobic carriers with different physicochemical properties such as pH-independent swellability, low-permeability (Eudragit® RS PO (E-RS)), pH-independent non-swellability (ethyl cellulose N7 (EC-N7)), and the presence of lipids (Compritol® 888 ATO (C-888)) with or without pore-forming agents were used to achieve the sustained release profile of DH. Mannitol (MNT) was chosen as the temporary pore-forming agent. The thermal analysis showed that both the drug and C-888 preserved their crystallinity within a solid dispersion. During a dissolution test, MNT could generate pores, and the drug release rate was proportionally correlated to the MNT content. Tailoring of the ratio of C-888 and MNT in the formulations along with an appropriate extrusion temperature profile resulted in the modified release of DH, and a preferable release pattern was obtained under these conditions. C-888 was chosen for the further investigations to obtain tablets with a high integrity. The optimized tablets were compared to the marketed formulation of Aricept® in terms of drug release profiles. The optimized formulation showed the stable and sustained release behavior of extended release profile, which was close to the release behavior of Aricept® with good tablet characteristics. It was concluded that the hot-melt extrusion technique can be utilized for the manufacturing of DH sustained release tablets with improved tablet integrity and characteristics by co-processing the tablet excipient with DH/C-888

Effect of Lutrol\u3csup\u3e®\u3c/sup\u3e F grades (poloxamer) on dissolution of Hot-melt extruded Kollidon\u3csup\u3e®\u3c/sup\u3e VA64-felodipine matrices

The objective of this study was to assess the potential of Lutrol® F grades as polymeric surfactants for dissolution enhancement of Kollidon®VA64-drug matrices produced by hot-melt extrusion (HME). The poorly soluble model drug felodipine (FEL) with a medium melting point was selected for this study. Two different grades of Lutrol® F (also called Kolliphor® P grades) were added into the HME systems to investigate their influence on the drug-incorporated matrices. Two grades of Lutrols i.e., Lutrol® F 68 (Kolliphor®P 188) and Lutrol® F 127 (Kolliphor®P 407) were studied as polymeric solubilizers. FEL was mixed with Kollidon®VA64, with or without Lutrol®F (alone or in combination) at predetermined amounts which resulted in 8 different formulations. Each blend was melt-extruded at the same extrusion conditions. Differential scanning calorimetry (DSC) and powder X-ray diffraction (PXRD) analyses were performed to evaluate their physicochemical properties. DSC and PXRD studies suggested the formation of amorphous solid dispersion for all extruded formulations. Dissolution studies revealed that the extrudates with Lutrol® F grades exhibited faster and higher release compared to formulations without Lutrol® F grades. Formulations with high drug loading, which did not include Lutrol® F grades, demonstrated low drug release profiles when compared with the same formulations containing Lutrol® F grades. Fourier transform infrared (FTIR) studies suggested that a stronger hydrogen bond has occurred between the (-NH) of FEL and (C=O) of the pyrrolidone group in Kollidon® VA 64. Overall, these studies suggested the potential of Lutrols in enhancing the dissolution rate of poorly soluble model drug FEL

Diosmin-Loaded Nanoemulsion-Based Gel Formulation: Development, Optimization, Wound Healing and Anti-Inflammatory Studies

The wound-healing process is complex and prone to interruption or failure, which can result in the development of chronic wounds that never heal. This can be overcome by seeking prompt medical attention, which will reduce the likelihood of complications and speed up the healing of the cutaneous wound. It has been established that functionalized engineered biomaterials are a possible strategy for starting skin wound care. The purpose of the current study is to develop a diosmin (DSM)-loaded nanoemulsion (NE)-based gel formulation and to investigate its wound healing and anti-inflammatory activity on rats. The DSM-loaded NEs (F1-F17) were developed and optimized with the help of Box–Behnken Design Expert. The DSM-Nes were developed using lauroglycol 90 (LG90®) as oil, Tween-80 as surfactant and transcutol-HP (THP) as co-surfactant. The optimized Nes showed globule size (41 ± 0.07 nm), polydispersity index (PDI) (0.073 ± 0.008) and percentage of entrapment efficiency (%EE) (87 ± 0.81%). This optimized DSM-loaded NEs (F1) was further evaluated and incorporated into 1% carbopol 940 gel. F1-loaded gel was then characterized for drug content, spreadability, in vitro release, wound healing, and anti-inflammatory studies. The developed gel of DSM was found to show significantly better (p < 0.05) wound-healing and anti-inflammatory activity

Exploitation of Design-of-Experiment Approach for Design and Optimization of Fast-Disintegrating Tablets for Sublingual Delivery of Sildenafil Citrate with Enhanced Bioavailability Using Fluid-Bed Granulation Technique

Sildenafil citrate undergoes first-pass metabolism, resulting in poor oral bioavailability at 25–41% of the administered dose. This study aimed to design and optimize fast-disintegrating tablets for the sublingual delivery of sildenafil citrate to improve bioavailability and facilitate rapid onset of action. The design-of-experiment (DoE) approach using 32 full factorial design was conducted to develop a new formulation of sildenafil fast-disintegrating sublingual tablets (FDSTs) using the fluid-bed granulation technique. The levels of partially pre-gelatinized starch (5–15%) and microcrystalline cellulose (10–60%) were selected as independent formulation variables. The prepared FDSTs were investigated for physical properties. Further, the optimum formulation was chosen for in vivo study in rabbits. Regression analysis showed that independent variables have a significant (p &lt; 0.05) influence on critical attributes of FDSTs. The optimized formulation showed acceptable mechanical strength (friability &lt; 1.0%) with very fast disintegration (14.561 ± 0.84 s) and dissolution (94.734 ± 2.76% after 15 min). Further, the optimized formulation demonstrated a significant increase (p &lt; 0.01) in Cmax and AUC0–∞ with short tmax compared to the market product (Viagra®). Based on these results, using the DoE approach, a high level of assurance was achieved for FDSTs’ product quality and performance

Formulation of Piperine–Chitosan-Coated Liposomes: Characterization and In Vitro Cytotoxic Evaluation

The present research work is designed to prepare and evaluate piperine liposomes and piperine–chitosan-coated liposomes for oral delivery. Piperine (PPN) is a water-insoluble bioactive compound used for different diseases. The prepared formulations were evaluated for physicochemical study, mucoadhesive study, permeation study and in vitro cytotoxic study using the MCF7 breast cancer cell line. Piperine-loaded liposomes (PLF) were prepared by the thin-film evaporation method. The selected liposomes were coated with chitosan (PLFC) by electrostatic deposition to enhance the mucoadhesive property and in vitro therapeutic efficacy. Based on the findings of the study, the prepared PPN liposomes (PLF3) and chitosan coated PPN liposomes (PLF3C1) showed a nanometric size range of 165.7 ± 7.4 to 243.4 ± 7.5, a narrow polydispersity index (&gt;0.3) and zeta potential (−7.1 to 29.8 mV). The average encapsulation efficiency was found to be between 60 and 80% for all prepared formulations. The drug release and permeation study profile showed biphasic release behavior and enhanced PPN permeation. The in vitro antioxidant study results showed a comparable antioxidant activity with pure PPN. The anticancer study depicted that the cell viability assay of tested PLF3C2 has significantly (p &lt; 0.001)) reduced the IC50 when compared with pure PPN. The study revealed that oral chitosan-coated liposomes are a promising delivery system for the PPN and can increase the therapeutic efficacy against the breast cancer cell line