scholarly journals Long-Acting Paliperidone Parenteral Formulations Based on Polycaprolactone Nanoparticles; the Influence of Stabilizer and Chitosan on In Vitro Release, Protein Adsorption, and Cytotoxicity

Pharmaceutics ◽  
2020 ◽  
Vol 12 (2) ◽  
pp. 160 ◽  
Author(s):  
Mohammed Elmowafy ◽  
Nabil K. Alruwaili ◽  
Khaled Shalaby ◽  
Khalid S. Alharbi ◽  
Waleed M. Altowayan ◽  
...  
Keyword(s):  
Protein Adsorption ◽  
In Vitro Release ◽  
Tween 80 ◽  
Pluronic F127 ◽  
Surface Charges ◽  
Cellular Toxicity ◽  
Chitosan Coating ◽  
Long Term Treatment ◽  
Long Acting ◽  
Stabilizer Type

Long-acting preparations containing the antipsychotic paliperidone for intramuscular injection has drawn considerable attention to achieve harmless long-term treatment. This study aimed to develop paliperidone loaded polycaprolactone (PCL) nanoparticles and investigate the influence of PCL/drug ratio, stabilizer type, and chitosan coating on physicochemical properties, protein adsorption, and cellular toxicity. Results showed that chitosan coating produced enlarged particle sizes, shifted the surface charges from negative into positive and did not influence encapsulation efficiencies. Chitosan coating relatively sustained the drug release especially in pluronic stabilized formulations. Pluronic F127 based formulations exhibited the least protein adsorption (384.3 μg/mL). Chitosan coating of Tween 80 and polyvinyl alcohol stabilized formulations significantly (p < 0.05) increased protein adsorption. Cellular viability was concentration-dependent and negatively affected by stabilizers. All formulations did not show cellular death at 1.56 μg/mL. Inflammatory responses and oxidative stress were less affected by Tween 80 compared with other stabilizers. Chitosan minimized all aspects of cellular toxicity. Collectively, stabilizer type and chitosan coating play critical roles in developing safe and effective long-acting PCL nanoparticles intended for parenteral drug delivery. The coated formulations containing Tween 80 and Pluronic F127 as stabilizers are warranted a future in vivo study to delineate its safety and efficacy profiles.

Optimization and Characterization of Aqueous Micellar Formulations for Ocular Delivery of an Antifungal Drug, Posaconazole

2020 ◽  
Vol 26 (14) ◽  
pp. 1543-1555 ◽  
Author(s):  
Meltem E. Durgun ◽  
Emine Kahraman ◽  
Sevgi Güngör ◽  
Yıldız Özsoy
Keyword(s):  
Particle Size ◽  
Zeta Potential ◽  
Size Distribution ◽  
Encapsulation Efficiency ◽  
Fungal Infections ◽  
In Vitro Release ◽  
Pluronic F127 ◽  
Glycol Succinate ◽  
Vitro Release

Background: Topical therapy is preferred for the management of ocular fungal infections due to its superiorities which include overcoming potential systemic side effects risk of drugs, and targeting of drugs to the site of disease. However, the optimization of effective ocular formulations has always been a major challenge due to restrictions of ocular barriers and physiological conditions. Posaconazole, an antifungal and highly lipophilic agent with broad-spectrum, has been used topically as off-label in the treatment of ocular fungal infections due to its highly lipophilic character. Micellar carriers have the potential to improve the solubility of lipophilic drugs and, overcome ocular barriers. Objective: In the current study, it was aimed optimization of posaconazole loaded micellar formulations to improve aqueous solubility of posaconazole and to characterize the formulations and to investigate the physical stability of these formulations at room temperature (25°C, 60% RH), and accelerated stability (40°C, 75% RH) conditions. Method: Micelles were prepared using a thin-film hydration method. Pre-formulation studies were firstly performed to optimize polymer/surfactant type and to determine their concentration in the formulations. Then, particle size, size distribution, and zeta potential of the micellar formulations were measured by ZetaSizer Nano-ZS. The drug encapsulation efficiency of the micelles was quantified by HPLC. The morphology of the micelles was depicted by AFM. The stability of optimized micelles was evaluated in terms of particle size, size distribution, zeta potential, drug amount and pH for 180 days. In vitro release studies were performed using Franz diffusion cells. Results: Pre-formulation studies indicated that single D-ɑ-tocopheryl polyethylene glycol succinate (TPGS), a combination of it and Pluronic F127/Pluronic F68 are capable of formation of posaconazole loaded micelles at specific concentrations. Optimized micelles with high encapsulation efficiency were less than 20 nm, approximately neutral, stable, and in aspherical shape. Additionally, in vitro release data showed that the release of posaconazole from the micelles was higher than that of suspension. Conclusion: The results revealed that the optimized micellar formulation of posaconazole offers a potential approach for topical ocular administration.

Formulation and Evaluation of Atorvastatin Calcium-Poly-ε-Caprolactone Nanoparticles Loaded Ocular Inserts for Sustained Release and Antiinflammatory Efficacy

2020 ◽  
Vol 21 (15) ◽  
pp. 1688-1698
Author(s):  
Germeen N.S. Girgis
Keyword(s):  
Sustained Release ◽  
In Vitro Release ◽  
Pluronic F127 ◽  
In Vivo Study ◽  
Average Weight ◽  
Drug Release Profile ◽  
Atorvastatin Calcium ◽  
Anti Inflammatory

Purpose: The work was performed to investigate the feasibility of preparing ocular inserts loaded with Poly-ε-Caprolactone (PCL) nanoparticles as a sustained ocular delivery system. Methods: First, Atorvastatin Calcium-Poly-ε-Caprolactone (ATC-PCL) nanoparticles were prepared and characterized. Then, the optimized nanoparticles were loaded within inserts formulated with Methylcellulose (MC) and Polyvinyl Alcohol (PVA) by a solvent casting technique and evaluated physically, for in-vitro drug release profile. Finally, an in-vivo study was performed on the selected formulation to prove non-irritability and sustained ocular anti-inflammatory efficacy compared with free drug-loaded ocuserts. Results: The results revealed (ATC-PCL) nanoparticles prepared with 0.5% pluronic F127 were optimized with 181.72±3.6 nm particle size, 0.12±0.02 (PDI) analysis, -27.4± 0.69 mV zeta potential and 62.41%±4.7% entrapment efficiency. Nanoparticles loaded ocuserts manifested compatibility between drug and formulation polymers. Moreover, formulations complied with average weight 0.055±0.002 to 0.143±0.023 mg, and accepted pH. ATC-PCL nanoparticles loaded inserts prepared by 5% MC showed more sustained, prolonged in-vitro release over 24h. In-vivo study emphasized non-irritability, ocular anti-inflammatory effectiveness represented by smaller lid closure scores, and statistically significant lowering in PMN count after 3h. Conclusion: These findings proposed a possibly simple, new and affordable price technique to prepare promising (ATC-PCL) nanoparticles loaded inserts to achieve sustained release with prolonged antiinflammatory efficacy.

scholarly journals Long-Acting Risperidone Dual Control System: Preparation, Characterization and Evaluation In Vitro and In Vivo

Pharmaceutics ◽  
2021 ◽  
Vol 13 (8) ◽  
pp. 1210
Author(s):  
Xieguo Yan ◽  
Shiqiang Wang ◽  
Kaoxiang Sun
Keyword(s):  
Drug Loading ◽  
Entrapment Efficiency ◽  
In Vitro Dissolution ◽  
Dissolution Behavior ◽  
In Vivo Evaluation ◽  
Long Term Treatment ◽  
Long Acting

Schizophrenia, a psychiatric disorder, requires long-term treatment; however, large fluctuations in blood drug concentration increase the risk of adverse reactions. We prepared a long-term risperidone (RIS) implantation system that can stabilize RIS release and established in-vitro and in-vivo evaluation systems. Cumulative release, drug loading, and entrapment efficiency were used as evaluation indicators to evaluate the effects of different pore formers, polymer ratios, porogen concentrations, and oil–water ratios on a RIS implant (RIS-IM). We also built a mathematical model to identify the optimized formulation by stepwise regression. We also assessed the crystalline changes, residual solvents, solubility and stability after sterilization, in-vivo polymer degradation, pharmacokinetics, and tissue inflammation in the case of the optimized formulation. The surface of the optimized RIS microspheres was small and hollow with 134.4 ± 3.5 µm particle size, 1.60 SPAN, 46.7% ± 2.3% implant drug loading, and 93.4% entrapment efficiency. The in-vitro dissolution behavior of RIS-IM had zero-order kinetics and stable blood concentration; no lag time was released for over three months. Furthermore, the RIS-IM was not only non-irritating to tissues but also had good biocompatibility and product stability. Long-acting RIS-IMs with microspheres and film coatings can provide a new avenue for treating schizophrenia.

Long-term outcomes in patients with schizophrenia treated with risperidone long-acting injection or oral antipsychotics in Spain: Results from the electronic Schizophrenia Treatment Adherence Registry (e-STAR)

2009 ◽  
Vol 24 (5) ◽  
pp. 287-296 ◽  
Author(s):  
J.M. Olivares ◽  
A. Rodriguez-Morales ◽  
J. Diels ◽  
M. Povey ◽  
A. Jacobs ◽  
...  
Keyword(s):  
Observational Study ◽  
Treatment Adherence ◽  
Prospective Observational Study ◽  
Clinical Symptoms ◽  
Retrospective Chart Review ◽  
Treatment Retention ◽  
Severity Scores ◽  
Long Term Treatment ◽  
Long Acting

AbstractBackgroundThe electronic Schizophrenia Treatment Adherence Registry (e-STAR) is a prospective, observational study of patients with schizophrenia designed to evaluate long-term treatment outcomes in routine clinical practice.MethodsParameters were assessed at baseline and at 3 month intervals for 2 years in patients initiated on risperidone long-acting injection (RLAI) (n = 1345) or a new oral antipsychotic (AP) (n = 277; 35.7% and 36.5% on risperidone and olanzapine, respectively) in Spain. Hospitalization prior to therapy was assessed by a retrospective chart review.ResultsAt 24 months, treatment retention (81.8% for RLAI versus 63.4% for oral APs, p < 0.0001) and reduction in Clinical Global Impression Severity scores (−1.14 for RLAI versus −0.94 for APs, p = 0.0165) were significantly higher with RLAI. Compared to the pre-switch period, RLAI patients had greater reductions in the number (reduction of 0.37 stays per patient versus 0.2, p < 0.05) and days (18.74 versus 13.02, p < 0.01) of hospitalizations at 24 months than oral AP patients.ConclusionsThis 2 year, prospective, observational study showed that, compared to oral antipsychotics, RLAI was associated with better treatment retention, greater improvement in clinical symptoms and functioning, and greater reduction in hospital stays and days in hospital in patients with schizophrenia. Improved treatment adherence, increased efficacy and reduced hospitalization with RLAI offer the opportunity of substantial therapeutic improvement in schizophrenia.

Sustained drug delivery optimizes long-term treatment of patients with schizophrenia

2004 ◽  
Vol 16 (6) ◽  
pp. 319-325 ◽  
Author(s):  
Pierre S. Chue ◽  
Peter D'Hoore ◽  
J. Michael Ramstack
Keyword(s):  
Antipsychotic Agents ◽  
Term Treatment ◽  
Treatment Programs ◽  
Sustained Drug Delivery ◽  
Partial Compliance ◽  
Long Term Treatment ◽  
Optimal Maintenance ◽  
Long Acting ◽  
The Impact

Chronic disorders such as schizophrenia require long-term treatment programs in order to maintain patients at the lowest level of symptomatology, reduce the likelihood of psychotic relapse, and support achievement of remission and recovery. Evidence suggests that treatment with long-acting injectable antipsychotics reduces the impact of partial compliance and provides predictable release of medication, assuring continuous therapeutic coverage. Until recently, only conventional antipsychotic agents were available in long-acting formulations, thereby foregoing the advantages of the atypical class. Atypical agents which are given orally have been shown to provide long-term efficacy and tolerability benefits compared with conventional agents, but are limited by the need for daily administration. The most recent pharmacological strategy to achieve optimal maintenance treatment has been to combine the benefits of an atypical antipsychotic with delivery in a water-based long-acting formulation. The first antipsychotic to achieve this combination – long-acting risperidone – may thus represent an important advance in the optimization of long-term treatment outcomes in patients with schizophrenia.

scholarly journals FORMULATION AND CHARACTERIZATION OF LAFUTIDINE NANOSUSPENSION FOR ORAL DRUG DELIVERY SYSTEM

2018 ◽  
Vol 10 (2) ◽  
pp. 20 ◽  
Author(s):  
Noor Mohammed Dawood ◽  
Shaimaa Nazar Abdal-hammid ◽  
Ahmed Abbas Hussien
Keyword(s):  
Particle Size ◽  
Fourier Transforms ◽  
Oral Drug Delivery ◽  
In Vitro Release ◽  
Tween 80 ◽  
Precipitation Method ◽  
Oral Drug ◽  
Tween 20 ◽  
Dissolution Profile ◽  
Particle Size Reduction

Objective: The objective of this study was to prepare nanosuspension of a practical water insoluble antiulcer drug which is lafutidine to enhance the solubility, dissolution rate with studying the effect of different formulation variables to obtain the best formula with appropriate physical properties and higher dissolution rate.Methods: Nanosuspension of lafutidine was prepared using solvent anti-solvent precipitation method using Polyvinylpyrrolidone K-90(PVP K-90) as the stabilizer. Ten formulations were prepared to show the effect of different variables in which two formulations showed the effect of stabilizer type, three formulations showed the effect of stabilizer concentration, two formulations showed the effect of combination of polymer with surfactant such as tween 80, three formulations show the effect of stirring speed and three formulations prepare to show the effect of addition of co-surfactant such as tween 20. All these formulations are evaluated for their particle size and entrapment efficiency and in vitro release. The selected one was evaluated for zeta potential, scanning electron microscope, atomic force microscopy, Fourier transforms infrared spectroscopy, differential scanning calorimetry, saturation solubility and stability study.Results: The formulations (F3-F10) were in the nano size. The optimum concentration of the stabilizer was in the formulation when the drug: polymer: surfactant ratio 1:4:4 and the optimum stirring speed was 1500 rpm. Dramatic effect on the particle size reduction was found by the addition of co-surfactant (tween 20) in formulation F7 that has a particle size 15.89±1.8 nm. The selected formula F7 showed an enhanced dissolution profile (10 min) compared to the pure drug at all-time intervals.Conclusion: The results show that the formulation that contains drug: PVP-K90: tween 80: tween 20 in ratio 1:4:2:2 is the best one and can be utilized to formulate lafutidine nanosuspension. 

scholarly journals Models and methods to characterise levonorgestrel release from intradermally administered contraceptives

2021 ◽  
Author(s):  
Adnan Al Dalaty ◽  
Benedetta Gualeni ◽  
Sion A. Coulman ◽  
James C. Birchall
Keyword(s):  
Ex Vivo ◽  
Extraction Procedure ◽  
In Vitro Release ◽  
Reversed Phase ◽  
Experimental Models ◽  
Detection Methods ◽  
Hormonal Contraceptives ◽  
Limit Of Quantification ◽  
Long Acting

AbstractMicroneedle (MN)-based technologies have been proposed as a means to facilitate minimally invasive sustained delivery of long-acting hormonal contraceptives into the skin. Intradermal administration is a new route of delivery for these contraceptives and therefore no established laboratory methods or experimental models are available to predict dermal drug release and pharmacokinetics from candidate MN formulations. This study evaluates an in vitro release (IVR) medium and a medium supplemented with ex vivo human skin homogenate (SH) as potential laboratory models to investigate the dermal release characteristics of one such hormonal contraceptive that is being tested for MN delivery, levonorgestrel (LNG), and provides details of an accompanying novel two-step liquid–liquid drug extraction procedure and sensitive reversed-phase HPLC–UV assay. The extraction efficiency of LNG was 91.7 ± 3.06% from IVR medium and 84.6 ± 1.6% from the medium supplemented with SH. The HPLC–UV methodology had a limit of quantification of 0.005 µg/mL and linearity between 0.005 and 25 µg/mL. Extraction and detection methods for LNG were exemplified in both models using the well-characterised, commercially available sustained-release implant (Jadelle®). Sustained LNG release from the implant was detected in both media over 28 days. This study reports for the first time the use of biologically relevant release models and a rapid, reliable and sensitive methodology to determine release characteristics of LNG from intradermally administered long-acting drug delivery systems. Graphical abstract

Sensing of Protein Adsorption by Composites Consisting of Silver Nanoparticles and Hydroxyapatite

2010 ◽  
Vol 76 ◽  
pp. 90-99
Author(s):  
Chikara Ohtsuki ◽  
Yuji Ichikawa ◽  
Hiroyuki Shibata ◽  
Tsukasa Torimoto ◽  
Ill Yong Kim
Keyword(s):  
Silver Nanoparticles ◽  
Protein Adsorption ◽  
Phosphate Buffer Solution ◽  
Trisodium Citrate ◽  
Localized Surface Plasmon ◽  
Surface Charges ◽  
Buffer Solution ◽  
Promising Candidate ◽  
Hydroxyapatite Powder ◽  
The Matrix

The sensing of protein adsorption by silver nanoparticles/hydroxyapatite composites was investigated using a phosphate buffer solution containing bovine serum albumin (BSA) or lysozyme (LSZ). The adsorption of BSA and LSZ on the composites prepared without using trisodium citrate was similar to plain hydroxyapatite, whereas composites prepared with trisodium citrate showed lower BSA adsorption and higher LSZ adsorption than plain hydroxyapatite powder. Because the ability of the adsorption is mainly governed by surface charges of the powders, the usage of trisodium citrate during the preparation is assumed to produce high negative charges on the surface. The protein adsorption resulted in peak shifts in localized surface plasmon resonance (LSPR) spectra. The peak shifts clearly corresponded to the concentration of the surrounding proteins up to the point of saturation of adsorption on the hydroxyapatite. The silver nanoparticles/hydroxyapatite composites are promising candidate materials for detection of protein adsorption by measurement of LSPR peak shifts, that may be attributed to changes in the dielectric properties of the matrix fluid surrounding the silver nanoparticles.

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