scholarly journals Drug Release from a Spherical Matrix: Theoretical Analysis for a Finite Dissolution Rate Affected by Geometric Shape of Dispersed Drugs

Pharmaceutics ◽  
2020 ◽  
Vol 12 (6) ◽  
pp. 582
Author(s):  
Yung-Sheng Lin ◽  
Ruey-Yug Tsay
Keyword(s):  
Drug Release ◽  
Release Rate ◽  
Shape Factor ◽  
Numerical Solutions ◽  
Drug Loading ◽  
Spherical Geometry ◽  
Detailed Comparison ◽  
Release Profile ◽  
Drug Release Profile ◽  
Drug Release Rate

Amending the neglect of finite dissolution in traditional release models, this study proposed a more generalized drug release model considering the simultaneous dissolution and diffusion procedure from a drug-loaded spherical matrix. How the shape factor (n = 0, 1/2, and 2/3 for the planar, cylindrical, and spherical geometry, respectively) of dispersed drug particles affected the release from the matrix was examined for the first time. Numerical solutions of this generalized model were validated by consensus with a short-time analytical solution for planar drugs and by the approach of the diffusion-controlled limits with Higuchi’s model. The drug release rate increases with the ratio of dissolution/diffusion rate (G) and the ratio of solubility/drug loading (K) but decreases with the shape factor of drug particles. A zero-order release profile is identified for planar drugs before starting the surface depletion layer, and also found for cylindrical and spherical dispersed drugs when K and G are small, i.e. the loaded drug is mainly un-dissolved and the drug release rate is dissolution-controlled. It is also shown that for the case of a small G value, the variation of drug release profile, due to the drug particle geometry, becomes prominent. Detailed comparison with the results of the traditional Higuchi’s model indicates that Higuchi’s model can be applied only when G is large because of the assumption of an instantaneous dissolution. For K = 1/101–1/2, the present analysis suggests an error of 33–85% for drug release predicted by Higuchi’s model for G = 100, 14–44% error for G = 101, while a less than 5% error for G ≧ 103.

scholarly journals Release profile and characteristics of electrosprayed particles for oral delivery of a practically insoluble drug

2012 ◽  
Vol 9 (75) ◽  
pp. 2437-2449 ◽  
Author(s):  
Adam Bohr ◽  
Jakob Kristensen ◽  
Mark Dyas ◽  
Mohan Edirisinghe ◽  
Eleanor Stride
Keyword(s):  
Drug Release ◽  
Oral Delivery ◽  
Drug Loading ◽  
Chemical Properties ◽  
Processing Parameters ◽  
Solute Concentration ◽  
Release Profile ◽  
Drug Release Profile ◽  
Physico Chemical ◽  
Dissolution Apparatus

Poly(lactic-co-glycolic acid) (PLGA) microspheres containing celecoxib were prepared via electrospraying, and the influence of three processing parameters namely flow rate, solute concentration and drug loading, on the physico-chemical properties of the particles and the drug-release profile was studied. Microspheres with diameters between 2 and 8 μm were produced and a near-monodisperse size distribution was achieved (polydispersivity indices of 6–12%). Further, the inner structure of the particles showed that the internal porosity of the particles increased with increasing solvent concentration. X-ray powder diffraction (XRPD) analysis indicated that the drug was amorphous and remained stable after eight months of storage. Drug release was studied in USP 2 (United States Pharmacopeia Dissolution Apparatus 2) dissolution chambers, and differences in release profiles were observed depending on the parametric values. Changes in release rate were found to be directly related to the influence of the studied parameters on particle size and porosity. The results indicate that electrospraying is an attractive technique for producing drug-loaded microspheres that can be tailored towards an intended drug-delivery application. Compared with the more conventional spray-drying process, it provides better control of particle characteristics and less aggregation during particle formation. In particular, this study demonstrated its suitability for preparing capsules in which the drug is molecularly dispersed and released in a sustained manner to facilitate improved bioavailability.

scholarly journals Studies on the Drug Loading and Release Profiles of Degradable Chitosan-Based Multilayer Films for Anticancer Treatment

Cancers ◽  
2020 ◽  
Vol 12 (3) ◽  
pp. 593 ◽  
Author(s):  
Hyeongdeok Sun ◽  
Daheui Choi ◽  
Jiwoong Heo ◽  
Se Yong Jung ◽  
Jinkee Hong
Keyword(s):  
Drug Release ◽  
Multilayer Film ◽  
Drug Loading ◽  
Building Blocks ◽  
Multilayer Films ◽  
Release Profile ◽  
Layer By Layer ◽  
Drug Release Profile ◽  
Sustained Drug Release ◽  
Release Profiles

This study demonstrates the possibility of developing a rapidly degradable chitosan-based multilayer film for controlled drug release. The chitosan (CHI)-based multilayer nanofilms were prepared with three different types of anions, hyaluronic acid (HA), alginic acid (ALG) and tannic acid (TA). Taking advantage of the Layer-by-Layer (LBL) assembly, each multilayer film has different morphology, porosity and thickness depending on their ionic density, molecular structure and the polymer functionality of the building blocks. We loaded drug models such as doxorubicin hydrochloride (DOX), fluorescein isothiocyanate (FITC) and ovalbumin (Ova) into multilayer films and analyzed the drug loading and release profiles in phosphate-buffered saline (PBS) buffer with the same osmolarity and temperature as the human body. Despite the rapid degradation of the multilayer film in a high pH and salt solution, the drug release profile can be controlled by increasing the functional group density, which results in interaction with the drug. In particular, the abundant carboxylate groups in the CHI/HA film increased the loading amount of DOX and decreased rapid drug release. The TA interaction with DOX via electrostatic interaction, hydrogen bonding and hydrophobic interaction showed a sustained drug release profile. These results serve as principles for fabricating a tailored multilayer film for drug delivery application.

scholarly journals Influence of Terpene Type on the Release from an O/W Nanoemulsion: Experimental and Theoretical Studies

Molecules ◽  
2020 ◽  
Vol 25 (12) ◽  
pp. 2747 ◽  
Author(s):  
Małgorzata Miastkowska ◽  
Paweł Śliwa
Keyword(s):  
Molecular Dynamics ◽  
Drug Release ◽  
Ursolic Acid ◽  
Drug Loading ◽  
In Vitro Release ◽  
Perillyl Alcohol ◽  
Release Profile ◽  
Theoretical Studies ◽  
Drug Release Profile ◽  
Experimental And Theoretical Studies

The interaction between a drug molecule and its carrier’s components is an important factor which influences the drug release profile. For this purpose, molecular dynamics (MD) may be the in silico tool which can help to understand the mechanism of drug loading/release. The aim of this work is to explain the effect of interactions between different types of terpenes, namely perillyl alcohol, forskolin, ursolic acid, and the nanoemulsion droplet core, on the release by means of experimental and theoretical studies. The basic nanoemulsion was composed of caprylic/capric triglyceride as the oil phase, polysorbate 80 as the emulsifier, and water. The in vitro release tests from a terpene-loaded nanoemulsion were carried out to determine the release profiles. The behavior of terpenoids in the nanoemulsion was also theoretically investigated using the molecular dynamics method. The forskolin-loaded nanoemulsion showed the highest percentage of drug release (almost 80% w/w) in contrast to ursolic acid and perillyl alcohol-loaded nanoemulsions (about 53% w/w and 19% w/w, respectively). The results confirmed that the kinetic model of release was terpene-type dependent. The zero-order model was the best to describe the ursolic acid release profile, while the forskolin and the perillyl alcohol followed a first-order and Higuchi model, respectively. Molecular dynamics simulations, especially energetical analysis, confirmed that the driving force of terpenes diffusion from nanoemulsion interior was their interaction energy with a surfactant.

scholarly journals Development and Characterization of a Theranostic Micelles System using TPGS with Docetaxel and Coumarin-6: A Dual Polymeric Nanocarrier System

2018 ◽  
Vol 5 (1) ◽  
pp. 99-108
Author(s):  
L.H. Ching ◽  
S. Mahmood ◽  
R. Edros ◽  
R.V. Kutty
Keyword(s):  
Drug Release ◽  
Early Stage ◽  
Drug Loading ◽  
Release Profile ◽  
Drug Release Profile ◽  
In Vitro Drug Release ◽  
Dual Modality ◽  
Coumarin 6 ◽  
Polymeric Nanocarrier

Theranostic micelles and polymeric nanocarrier-based drug delivery system are well known techniques that involve a diagnostic agent in polymeric micelles for a combination of therapy by using a co-delivery approach which can help in detection of a cancer cell in an early stage, increase killing effect and suppress multi-drug resistance (MDS) for better therapeutic effectiveness. The aim of this study is to develop a dual modality micellar system using D-α-tocopheryl polyethylene glycol 1000 succinate (TPGS) as a nanocarrier for co-delivery of docetaxel as a model chemotherapeutic drug and coumarin-6 as a model fluorescence imaging agent for simultaneous cancer imaging and therapy in an early stage. The theranostic micelles were prepared by a solvent casting method and characterized by their particle size, drug loading, drug encapsulation efficiency (EE) and in-vitro drug release profile. These dual modality micellar system TPDC6 micelles were successfully developed with average particle size of 79.59±0.57 nm in diameter and drug loading up to 15.46±1.02 % (EE of 78.99±1.26%) and 9.83±0.76 % (EE of 36.20±0.89%) for docetaxel and coumarin-6 respectively. Besides, the in-vitro drug release profile of the micelles revealed a desired sustained and controlled drug release manner for both docetaxel (21.62±0.36%) and coumarin-6 (10.70±0.46%). In conclusion, the micelles size obtained is in the favourable range for passive targeting through enhanced permeability and retention (EPR) effect and the drug loading and encapsulation efficiency attained are adequate for therapy and diagnosis purposes on cancer cells. This dual modality system is taking great advantages for tumour imaging and inhibition of tumour growth which is very important for early cancer detection.

scholarly journals Cisplatin-Loaded Polybutylcyanoacrylate Nanoparticles with Improved Properties as an Anticancer Agent

2019 ◽  
Vol 20 (7) ◽  
pp. 1531 ◽  
Author(s):  
Seyed Alavi ◽  
Sitah Muflih Al Harthi ◽  
Hasan Ebrahimi Shahmabadi ◽  
Azim Akbarzadeh
Keyword(s):  
Lung Cancer ◽  
Drug Release ◽  
Drug Loading ◽  
Release Profile ◽  
Therapeutic Effects ◽  
Drug Release Profile ◽  
Standard Drug ◽  
Loading Efficiency ◽  
Drug Loading Efficiency

This study aims to improve the cytotoxicity and potency of cisplatin-loaded polybutylcyanoacrylate (PBCA) nanoparticles (NPs) for the treatment of lung cancer through the modulation of temperature and polyethylene glycol (PEG) concentration as effective factors affecting the NPs’ properties. The NPs were synthesized using an anionic polymerization method and were characterized in terms of size, drug loading efficiency, drug release profile, cytotoxicity effects, drug efficacy, and drug side effects. In this regard, dynamic light scattering (DLS), scanning electron microscopy (SEM), 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) methods, and hematoxylin and eosin (H&E) staining were used. The results showed that the size and the drug loading efficiency of the synthesized spherical NPs were 355–386 nm and 14–19%, respectively. Also, the drug release profile showed a controlled and slow drug release pattern with approximately 10% drug release over 48 h. In addition, the NPs significantly increased the cytotoxicity of the cisplatin in vitro environment by approximately 2 times and enhanced the therapeutic effects of the drug in vivo environment by increasing the survival time of lung-cancer-bearing mice by 20% compared to the standard drug receiver group. Also, the nanoformulation decreased the drug toxicity in an in vivo environment. According to the results, increasing the temperature and PEG concentration improved the properties of the drug loading efficiency, drug release profile, and cytotoxicity effect of drug-loaded NPs. Consequently, the synthesized formulation increased the survival of tumor-bearing mice and simultaneously decreased the cisplatin toxicity effects. In conclusion, the prepared nanoformulation can be considered a promising candidate for further evaluation for possible therapeutic use in the treatment of lung cancer.

scholarly journals Factors affecting performance and manufacturability of naproxen Liqui-Pellet

2020 ◽  
Vol 28 (2) ◽  
pp. 567-579
Author(s):  
Matthew Lam ◽  
Ali Nokhodchi
Keyword(s):  
Drug Release ◽  
Release Rate ◽  
Flow Property ◽  
Major Effect ◽  
Coating Material ◽  
Drug Release Profile ◽  
Pellet Size ◽  
Drug Release Rate ◽  
R Value ◽  
Pellet Formulation

Abstract Aim Liqui-Pellet is potentially an emerging next-generation oral pill, which has shown promising results with unique advantages as well as displaying potential for commercial feasibility. Since Liqui-Pellet technology is still in its infancy, it is important to explore the parameters that can affect its performance, particularly the drug release rate. Therefore, the aim of this study is to investigate thoroughly the effect of Avicel PH101 (carrier) and Aerosil 300 (coating material) ratio (R-value) in Liqui-Pellet. Methods Key parameter for Liqui-Pellet formulation in this study was the ratio of carrier and coating material. Tests were carried out to assess the physicochemical properties of different formulations. This involved looking into particle size, robustness, flowability, solid-state and drug release profile. The morphology of Liqui-Pellet was investigated by SEM. Results It is found that R-value does not have a major effect on the success of Liqui-Pellet production. However, R-value does seem to have an effect on Liqui-Pellet size at a certain water content level and a slight effect on the drug release rate. A decrease in Avicel PH101 concentration and an increase in Aerosil 300 concentration in Liqui-Pellet formulations can reduce Liqui-Pellet size and slightly increase drug release rate by 9% after 2 h. The data shows Liqui-Pellet is resistant to friability, able to achieve exceptional flow property and have smooth surfaces, which is critical for applying coatings technology. Such properties are ideal in terms of commercial manufacturing. The XRPD and DSC both show the reduction in formulation crystallinity, which is expected in Liqui-Pellet formulation as a result of solubility of the drug in the co-solvent used in the preparation of Liqui-Pellets. Conclusion Overall it seems that R-value can affect Liqui-Pellet drug release rate and size but not on the production success rate. Graphical abstract

scholarly journals Preparation of Silymarin–quercetin Loaded Nanoparticles by Spontaneous Emulsification Solvent Diffusion Method Using D-alpha-tocopheryl Poly (Ethylene Glycol) 1000 Succinate

2021 ◽  
pp. 84-94
Author(s):  
S. Senthila ◽  
P. Manoj Kumar ◽  
P. Venkatesan
Keyword(s):  
Electron Microscopy ◽  
Drug Release ◽  
Ethylene Glycol ◽  
Encapsulation Efficiency ◽  
Drug Loading ◽  
Release Profile ◽  
Poly Ethylene Glycol ◽  
Drug Release Profile ◽  
Spontaneous Emulsification ◽  
Poly Ethylene

Silymarin, a flavonolignan, derived from Silybum marianum, family Asteraceae has long been used as a hepatoprotective remedy. Silymarin has cytoprotective activities due to its antioxidant property and free radical scavenging activity. The pharmacokinetic studies of past three decades revealed that silymarin has poor absorption, rapid metabolism especially by Phase II metabolism and ultimately poor oral bioavailability. Quercetin, a flavonoid present in edible vegetables and fruits, It is a potent antioxidant and shows a wide range of biological functions. Quercetin improves blood levels and efficacy of number of drugs since it is P-Glycoprotein inhibitor and also inhibits drug metabolizing enzymes. Both silymarin and quercetin were, poorly soluble in the water shows low bioavailability. The advanced type of formulation like polymeric nanoparticles (PNPs) can be successfully utilised for bioavailability enhancement and targeting the Silymarin-quercetin to hepatocytes. A controlled release PNPs of silymarin-quercetin were prepared by spontaneous emulsification solvent diffusion (SESD) method using Poly Lactic-co-Glycolic Acid (PLGA) as biodegradable polymer, D-alpha-tocopheryl poly (ethylene glycol) 1000 succinate (TPGS) used as a solubilizer, as an emulsifier. TPGS as an emulsifier and further as a matrix material blended with PLGA was used to enhance the encapsulation efficiency and improve the drug release profile of nanoparticles. Different formulations with various drug: polymer ratios and volume and concentration of surfactant, centrifugation time were evaluated. The effect of formulation parameters such as drug/polymer ratio, volume and surfactant content were evaluated. The surface morphology and size of the nanoparticles were studied by scanning electron microscopy (SEM) Transmission electron microscopy (TEM). Drug encapsulation efficiency and in vitro drug release profiles of nanoparticles were determined using UV spectrophotometry. The nanoparticles prepared with combination of both the drugs in this study were spherical with size range of 100–200 nm. It was shown that TPGS was a good emulsifier for producing nanoparticles of hydrophobic drugs and improving the encapsulation efficiency and drug loading and drug release profile of nanoparticles. Although the amount of the TPGS used had a significant effect on the nanoparticle size and morphology, the drug loading and release profile of nanoparticles

Blending of PLGA-PEG-PLGA for Improving the Erosion and Drug Release Profile of PCL Microspheres

2020 ◽  
Vol 21 (11) ◽  
pp. 1079-1087
Author(s):  
Siyuan Wang ◽  
Xiaobo Feng ◽  
Ping Liu ◽  
Youxiu Wei ◽  
Baojun Xiao
Keyword(s):  
Drug Release ◽  
Release Rate ◽  
Loss Rate ◽  
Mass Loss Rate ◽  
Reduction Rate ◽  
Release Profile ◽  
Drug Release Profile ◽  
Hydrophobic Property ◽  
Erosion Rates ◽  
Phasic Release

Background: PCL has a long history as an industrialized biomaterial for preparing microspheres, but its hydrophobic property and slow degradation rate often cause drug degeneration, quite slow drug release rate and undesirable tri-phasic release profile. Materials and Methods: In this study, we used the blending material of PLGA-PEG-PLGA and PCL to prepare microspheres. The microspheres degradation and drug release behaviors were evaluated through their molecular weight reduction rate, mass loss rate, morphology erosion and drug release profile. The hydrophilic PLGA-PEG-PLGA is expected to improve the degradation and drug release behaviors of PCL microspheres. Results: Microspheres in blending materials exhibited faster erosion rates than pure PCL microspheres, forming holes much quickly on the particle’s surface for the drug to diffuse out. A higher proportion of PLGA-PEG-PLGA caused faster degradation and erosion rates. The blending microspheres showed much faster drug release rates than pure PCL microspheres. Conclusion: With blending of 25wt% PLGA-PEG-PLGA, the release rate of microspheres speeded up significantly, while, with a further increase of PLGA-PEG-PLGA proportion (50%, 75%, 100%), it accelerated a little. The microspheres with PCL/PLGA-PEG-PLGA of 1/1 exhibited a linear-like drug release profile. The results could be a guideline for preparing microspheres based on blending materials to obtain a desirable release.

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