scholarly journals Double-Walled Poly-(D,L-lactide-co-glycolide) (PLGA) and Poly(L-lactide) (PLLA) Nanoparticles for the Sustained Release of Doxorubicin

Polymers ◽  
2021 ◽  
Vol 13 (19) ◽  
pp. 3230
Author(s):  
M. Margarida Cardoso ◽  
Inês N. Peca ◽  
Telma Lopes ◽  
Rui Gardner ◽  
A. Bicho
Keyword(s):  
Rate Control ◽  
Release Kinetics ◽  
Drug Distribution ◽  
In Vitro Tests ◽  
Cellular Viability ◽  
Release Rates ◽  
Zero Order Release ◽  
Evaporation Technique ◽  
Model Drug

Double-walled nanoparticles (DWNPs), containing doxorubicin as a model drug, were produced using poly-(D,L-lactide-co-glycolide) (PLGA) and poly(L-lactide) (PLLA) by the solvent evaporation technique. Double-walled microparticles containing doxorubicin were also produced to make possible the examination of the inner morphology and drug distribution using optical and fluorescence microscopy. The produced microparticles present a double-walled structure with doxorubicin solubilized in the PLGA-rich phase. The DWNPs produced present very low initial burst values and a sustained DOX release for at least 90 days with release rates decreasing with the increase in the PLLA amount. Zero-order release kinetics were obtained after day 15. The results support that the PLLA layer acts as a rate control barrier and that the diffusion of doxorubicin from the drug-loaded inner PLGA core can be retarded by an increase in the thickness of the unloaded outer layer. The unloaded double-walled nanoparticles produced were used in in vitro tests with CHO cells and demonstrate that they are nontoxic, while the double-walled nanoparticles loaded with doxorubicin caused a great cellular viability and decreased when tested in vitro.

scholarly journals Characterization and Compatibility Studies of Different Rate Retardant Polymer Loaded Microspheres by Solvent Evaporation Technique: In Vitro-In Vivo Study of Vildagliptin as a Model Drug

2015 ◽  
Vol 2015 ◽  
pp. 1-12 ◽  
Author(s):  
Irin Dewan ◽  
Swarnali Islam ◽  
Md. Sohel Rana
Keyword(s):  
Drug Release ◽  
Promising Result ◽  
Release Kinetics ◽  
Type Ii Diabetes Mellitus ◽  
Solvent Evaporation ◽  
Ftir Studies ◽  
Evaporation Technique ◽  
Model Drug

The present study has been performed to microencapsulate the antidiabetic drug of Vildagliptin to get sustained release of drug. The attempt of this study was to formulate and evaluate the Vildagliptin loaded microspheres by emulsion solvent evaporation technique using different polymers like Eudragit RL100, Eudragit RS100, Ethyl cellulose, and Methocel K100M. In vitro dissolution studies were carried out in 0.1 N HCl for 8 hours according to USP paddle method. The maximum and minimum drug release were observed as 92.5% and 68.5% from microspheres, respectively, after 8 hours. Release kinetics were studied in different mathematical release models to find out the linear relationship and release rate of drug. The SEM, DSC, and FTIR studies have been done to confirm good spheres and smooth surface as well as interaction along with drug and polymer. In this experiment, it is difficult to explain the exact mechanism of drug release. But the drug might be released by both diffusion and erosion as the correlation coefficient (R2) best fitted with Korsmeyer model and release exponent (n) was 0.45–0.89. At last it can be concluded that all in vitro and in vivo experiments exhibited promising result to treat type II diabetes mellitus with Vildagliptin microspheres.

Design and Charecterization of Anticancer Engineered Resealed Erythrocytes

1970 ◽  
Vol 1 (3) ◽  
pp. 243-250
Author(s):  
R. C. Doijad ◽  
N. V. Deshmukh ◽  
D. S. Bhambere ◽  
Rony Joseph ◽  
F. V. Manvi
Keyword(s):  
Targeted Delivery ◽  
Release Kinetics ◽  
Reticuloendothelial System ◽  
Sem Analysis ◽  
In Vitro Tests ◽  
Mean Corpuscular Hemoglobin ◽  
Laser Scattering ◽  
Zero Order Kinetics ◽  
Model Drug

A number of investigators have been focusing their attention on the encapsulation of antineoplastic drugs within erythrocytes to diminish their side effects. In this study, human erythrocytes have been loaded by methotrexate (MTX) as a model drug using hypotonic hemolysis method for targeted delivery of this drug. A series of in vitro tests have been carried out to characterize the carrier cells in vitro, including loading parameters, hemoglobin release kinetics, particle size distribution, SEM analysis, osmotic and turbulence fragilities. Carrier erythrocytes having acceptable loading parameters, released their drug content according to zero-order kinetics. Mean corpuscular hemoglobin content values of the cells decreased, the apparent cell sizes measured using dynamic laser scattering, were not significantly different from normal erythrocytes, but the real sizes, measured using SEM, and surface topologies were quite different between loaded and unloaded cells. The MTX-loaded cells were remarkably more fragile compared to the normal cells. Drug loaded erythrocytes showed preferential drug targeting to liver followed by lungs, kidney and spleen. Totally, MTX-loaded erythrocytes seem to be a promising delivery system for targeting the drug to reticuloendothelial system (RES).

SYNTHESIS AND CHARACTERIZATION OF THIOLATED GUM KONDAGOGU AND EVALUATION AS MUCOADHESIVE POLYMER

INDIAN DRUGS ◽  
2020 ◽  
Vol 57 (01) ◽  
pp. 37-43
Author(s):  
Ashwin A. Patil ◽  
Ketan B. Patil ◽  
Laxmikant R. Zawar
Keyword(s):  
Drug Release ◽  
Release Kinetics ◽  
Matrix Tablet ◽  
Disintegration Time ◽  
Weight Variation ◽  
Zero Order Release ◽  
Gum Kondagogu ◽  
Ellman’S Method

Present work focused on thiolation for enhancing the mucoadhesive potential of Gum kondagogu (GK). Thiolation of GK was done by esterification process with 80 % thioglycolic acid in presence of 7N HCl. Thiolated Gum kondagogu (ThioGK) was determined to possess 1.59 ±0.04 mmol of thiol groups/g of the polymer by Ellman’s method. ThioGK was characterized by FTIR, NMR, DSC, XRD, and FE-SEM. The tablets were prepared by direct compression using 75 mg of ThioGK and GK. Tablets containing ThioGK (F1) and GK (F2) were subjected to evaluation of weight variation, hardness and friability and show enhanced disintegration time, swelling behavior, drug release and mucoadhesion. In vitro drug release of batch F1 exhibits complete release of drug in 24 hr with zero order release kinetics. Comparative mucoadhesive strength was studied using chicken ileum by texture analyzer and revealed higher mucoadhesion of tablet containing ThioGK. From the above study, ThioGK was suitability exploited as mucoadhesive sustained release matrix tablet.

Formulation and evaluation of proniosome loaded sertaconazole nitrate for topical application

2021 ◽  
Vol 1 (2) ◽  
pp. 023-037
Author(s):  
Shailaja D ◽  
Latha K ◽  
Manasa D ◽  
Shirisha A ◽  
Padmavathi R ◽  
...  
Keyword(s):  
Ex Vivo ◽  
Release Kinetics ◽  
Skin Irritation ◽  
Water Soluble ◽  
Ionic Surfactants ◽  
Release Mechanism ◽  
Stability Studies ◽  
Zero Order Release ◽  
Poorly Soluble

Proniosomal technology is a novel solution for poorly soluble drugs. Proniosomes are water-soluble carrier particles which are coated with non-ionic surfactants. Proniosomal gels were prepared by coacervation phase separation method using non-ionic surfactants, lipid carriers and cholesterol as a membrane stabilizer. FTIR compatibility studies revealed that the drug and excipients were compatible. All formulations were evaluated for pH, drug content, extrudability, spreadability, viscosity, in-vitro, ex-vivo, skin irritation and stability studies. Among formulations prepared, F80H1 has shown higher % EE (83.02) and least diffusion through dialysis membrane i.e., 17.68%. With ex-vivo studies, F80H1 formulation has shown highest skin deposition and lower flux of sertaconazole nitrate through the rat skin. F80H1 was selected as final optimized formulation. F80H1 exhibited good stability and SEM studies revealed that the vesicles were spherical in shape. The optimized formulation was found to follow zero order release kinetics and korsmeyer-peppas release mechanism. F80H1 found to be non-irritant and stable from skin irritation and stability studies.

scholarly journals Formulation and investigation of crushed puffed rice-chitosan-HPMC based polymeric blends as carrier for sustained stomach specific drug delivery of piroxicam using 3(2) Taguchi mathematical design studies

2018 ◽  
Vol 6 (11) ◽  
pp. 61-80 ◽  
Author(s):  
Shashank Soni ◽  
Veerma Ram ◽  
Anurag Verma
Keyword(s):  
Drug Release ◽  
Release Kinetics ◽  
Drug Loading ◽  
Hydroxypropyl Methylcellulose ◽  
Research Work ◽  
Pharmaceutical Journal ◽  
Weight Variation ◽  
Zero Order Release ◽  
Puffed Rice

In the present experimental investigation an attempt has been made to assess the utility of Crushed Puffed Rice (CPR)-High Molecular Weight Chitosan (HMWCH)-Hydroxypropyl Methylcellulose K15M (HPMC K15M) as a polymeric carrier for the sustained stomach delivery of Piroxicam (PRX). A total of nine formulations were prepared by using 3 (2) Taguchi factorial design, physically blending drug and polymer(s) followed by encapsulation into hard gelatin capsules size 1. The prepared capsules were evaluated for various performance such as weight variation, drug contents, in vitro buoyancy and drug release in 0.1 M HCl. The effect of drug loading on in vitro performance of the formulations was also determined. Crushed puffed rice (CPR) remained buoyant for up to average time span of 06 hr as an unwetted irregular mass in 0.1 M HCl. However, when combined with HMWCH or HPMC K15M or HPMC K15M + HMWCH a low -density cylindrical raft type hydrogel was formed which remained buoyant for up to 12 hr and released up to 99% drug in a sustained manner from 8 to 12 hr following zero order release kinetics. It was also observed that drug release from drug + CPR matrices followed Fickian mechanism. Combination of CPR + HMWCH or HMWCH + HPMC K15M also follows Fickian mechanism. Obtained data from the research work suggests that CPR in combination with HMWCH or HPMC K15M or HPMC has sufficient potential to be used as a carrier for stomach specific delivery of gastric irritant drug like PRX.Soni et al., International Current Pharmaceutical Journal, April 2018, 6(11): 61-80http://www.icpjonline.com/documents/Vol6Issue11/01.pdf

scholarly journals Development of a reservoir type prolonged release system with felodipine via simplex methodology

2015 ◽  
Vol 89 (1) ◽  
pp. 128-136
Author(s):  
Rareș Iuliu Iovanov ◽  
Ioan Tomuță ◽  
Sorin Emilian Leucuța
Keyword(s):  
Simplex Method ◽  
Release Kinetics ◽  
Prolonged Release ◽  
Lauryl Sulfate ◽  
Pore Former ◽  
Release System ◽  
Reservoir Type ◽  
Model Drug ◽  
Kinetics Of

Background and aims. Felodipine is a dihydropyridine calcium antagonist that presents good characteristics to be formulated as prolonged release preparations. The aim of the study was the formulation and in vitro characterization of a reservoir type prolonged release system with felodipine, over a 12 hours period using the Simplex method.Methods. The first step of the Simplex method was to study the influence of the granules coating method on the felodipine release. Furthermore the influence of the coating polymer type, the percent of the coating polymer and the percent of pore forming agent in the coating on the felodipine release were studied. Afterwards these two steps of the experimental design the percent of Surelease applied on the felodipine loaded granules and the percent of pore former in the polymeric coating formulation variables were studied. The in vitro dissolution of model drug was performed in phosphate buffer solution (pH 6.5) with 1% sodium lauryl sulfate. The released drug quantification was done using an HPLC method. The release kinetics of felodipine from the final granules was assessed using different mathematical models.Results. A 12 hours release was achieved using granules with the size between 315 – 500 µm coated with 45% Surelease with different pore former ratios in the coating via the top-spray method.Conclusion. We have prepared prolonged release coated granules with felodipine using a fluid bed system based on the Simplex method. The API from the studied final formulations was released over a 12 hours period and the release kinetics of the model drug substance from the optimized preparations fitted best the Higuchi and Peppas kinetic models. 

Controlled Release of Bone Growth Factors from Injectable, Biodegradable Polymer Scaffolds for Bone Tissue Engineering

2000 ◽  
Vol 662 ◽  
Author(s):  
Elizabeth L. Hedberg ◽  
Antonios G. Mikos
Keyword(s):  
Growth Factors ◽  
Controlled Release ◽  
Bone Growth ◽  
Bone Ingrowth ◽  
Release Kinetics ◽  
Salt Content ◽  
Burst Effect ◽  
Plga Microparticles ◽  
Model Drug

AbstractThe objective of this research is to fabricate injectable, polymeric composites that will act as scaffolds for bone ingrowth as well as carriers for the controlled release of bone growth factors. To that end, the injectable polyester poly(propylene fumarate) (PPF) was loaded with poly(DLlactic-co-glycolic acid) (PLGA) microparticles carrying the model drug FITC-dextran. This preparation was then crosslinked with N-vinyl pyrrolidinone in the presence of benzoyl peroxide as initiator and sodium chloride (NaCl) as leachable porogen. The encapsulation of growth factors in microparticles is necessary to minimize their denaturation during scaffold crosslinking. PLGA microparticles (0.04 g microparticles/g PPF) were incorporated into PPF composites having variable NaCl weight percents (50 and 70 wt% NaCl) and the effect on FITC-dextran release kinetics was determined in vitro for cylinders of diameter 6.5 mm and height 13.0 mm. The FITC-dextran loaded microparticles alone exhibited a large initial burst effect, while the composite materials displayed a smaller burst effect and a longer linear region of release. At day 3, 54.6±2.1%, 5.1±0.9%, and 12.5±0.3% of loaded FITC-dextran was released into pH 7.4 phosphate buffered saline from the microparticles, the 50 wt% NaCl, and the 70 wt% NaCl composites, respectively. By day 28, 90.9±6.9%, 12.7±1.7%, and 34.4±0.4% of loaded FITC-dextran was released. Our results demonstrate that PLGA microparticles can be incorporated into PPF composites and that the release kinetics of FITC-dextran can be systematically manipulated through alteration of the composite initial salt content.

10 IN VITRO PROGESTERONE RELEASE KINETICS: A COMPARATIVE STUDY OF DIFFERENT INTRAVAGINAL DEVICES USED IN CATTLE

2011 ◽  
Vol 23 (1) ◽  
pp. 111
Author(s):  
G. C. Gomes ◽  
A. Kehrle ◽  
M. Maturana Filho ◽  
C. V. F. Caetano ◽  
J. R. V. Pimentel ◽  
...  
Keyword(s):  
Statistical Difference ◽  
Release Kinetics ◽  
In Vitro Tests ◽  
Water Mixture ◽  
The Third ◽  
Metabolism Rate ◽  
Alcohol Water ◽  
Reproduction Cost ◽  
Second Use

Since progesterone releasing devices have been used for oestrous cycle control, many studies have been done to evaluate the reduce reproduction cost. However, there are few studies about reused devices. The aim of this study was to evaluate and compare in vitro P4 releasing kinetics from 3 commercially available devices: Sincrogest® (SIN, 1 g of P4), Cronipres® (CRO, 1 g of P4 and 3 rings of 0.1 g of P4 for the third use), and Primer® (PRI, 1 g of P4). For each device, new (first use, n = 2), once-used (second use, n = 2), and twice-used (third use, n = 2) devices were tested. The tests were performed in a dissolutor sink using an alcohol/water mixture (60/40, vol/vol) as a release media. Samples were collected at 0–24 h (1P), 24–48 h (2P), 48–72 h (3P), and 72–96 h (4P). Table 1 shows the P4 amount (mg) and standard deviation in the periods in which there was statistical difference (P < 0.05; a–cdifferent letters in the same period differ statistically). The 3 brands of P4 devices differ in 2 of 4, 3 of 4, and 1 of 4 intervals for 1st-, 2nd, and 3rd-use device tests respectively. Additionally, P4 release decreased according to the number of previous uses. It is known that in vitro tests are more sensible to detect differences between devices. Nevertheless, these findings suggest the possibility of targeting different device categories for different animal categories depending on the animal steroid metabolism rate and consequent need for exogenous P4. However, for such a claim, further studies on this topic are needed. Table 1.Comparison between the 3 types in each of 3 uses Supported by FAPESP – Fundação de Amparo a Pesquisa do estado de São Paulo.

scholarly journals Drug Release Kinetics of Electrospun PHB Meshes

Materials ◽  
2019 ◽  
Vol 12 (12) ◽  
pp. 1924 ◽  
Author(s):  
Vojtech Kundrat ◽  
Nicole Cernekova ◽  
Adriana Kovalcik ◽  
Vojtech Enev ◽  
Ivana Marova
Keyword(s):  
Release Kinetics ◽  
Entrapment Efficiency ◽  
Toxic Substances ◽  
Antimicrobial Efficiency ◽  
Vis Spectroscopy ◽  
Model Drug ◽  
Phosphate Buffered Saline ◽  
Kinetics Of

Microbial poly(3-hydroxybutyrate) (PHB) has several advantages including its biocompatibility and ability to degrade in vivo and in vitro without toxic substances. This paper investigates the feasibility of electrospun PHB meshes serving as drug delivery systems. The morphology of the electrospun samples was modified by varying the concentration of PHB in solution and the solvent composition. Scanning electron microscopy of the electrospun PHB scaffolds revealed the formation of different morphologies including porous, filamentous/beaded and fiber structures. Levofloxacin was used as the model drug for incorporation into PHB electrospun meshes. The entrapment efficiency was found to be dependent on the viscosity of the PHB solution used for electrospinning and ranged from 14.4–81.8%. The incorporation of levofloxacin in electrospun meshes was confirmed by Fourier-transform infrared spectroscopy and UV-VIS spectroscopy. The effect of the morphology of the electrospun meshes on the levofloxacin release profile was screened in vitro in phosphate-buffered saline solution. Depending upon the morphology, the electrospun meshes released about 14–20% of levofloxacin during the first 24 h. The percentage of drug released after 13 days increased up to 32.4% and was similar for all tested morphologies. The antimicrobial efficiency of all tested samples independent of the morphology, was confirmed by agar diffusion testing.

scholarly journals PREPARATION, CHARACTERISATION AND EVALUATION OF ROPINIROLE HYDROCHLORIDE LOADED CONTROLLED RELEASE MICROSPHERES USING SOLVENT EVAPORATION TECHNIQUE

2018 ◽  
Vol 10 (6) ◽  
pp. 57
Author(s):  
Koyel Kar ◽  
R. N. Pal ◽  
N. N. Bala
Keyword(s):  
Controlled Release ◽  
Drug Release ◽  
Release Kinetics ◽  
Drug Loading ◽  
Solvent Evaporation ◽  
In Vitro Drug Release ◽  
Aqueous Solvent ◽  
Evaporation Technique ◽  
Ropinirole Hydrochloride

Objective: The major objective of the research work was to design, characterise and evaluate controlled release microspheres of ropinirole hydrochloride by using non-aqueous solvent evaporation technique to facilitate the delivery of the drug at a predetermined rate for a specific period of time.Methods: Ropinirole hydrochloride microspheres were prepared by using different low-density polymers such as eudragit RL 100, eudragit RS 100 and ethylcellulose either alone or in combination with the help of non-aqueous solvent evaporation technique. All the formulated microparticles were subjected to various evaluation parameters such as particle size analysis, micrometric properties, drug entrapment efficiency, percentage drug loading, percentage yield and in vitro drug release study. The compatibility of the drug and polymers was confirmed by physical compatibility study, fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC) and x-ray diffraction study (XRD). The formation of the most optimized batch of the microsphere (F12) was confirmed by scanning electron microscopy (SEM), DSC, FTIR, and XRD. In vitro drug release study and in vitro drug release kinetics study of the formulated microspheres were also carried out.Results: Drug-polymer compatibility studies performed with the help of FTIR and DSC indicated that there were no interactions. Results revealed that non-aqueous solvent evaporation technique was a suitable technique for the preparation of microspheres as most of the formulations were discrete, free-flowing and spherical in shape with a good yield of 55.67% to 80.09%, percentage drug loading of 35.52% to 94.50% and percentage drug entrapment efficiency of 36.24% to 95.07%. Different drug-polymer ratios, as well as the combination of polymers, played a significant role in the variation of over-all characteristics of formulations. Based on the data of various evaluation parameters such as particle size analysis, percentage drug loading, percentage drug entrapment, percentage yield, rheological studies and in vitro drug release characteristics, formulation F12 was found to fulfil the criteria of ideal controlled release drug delivery system. F12 showed controlled release till the 14th hour (97.99%) and its in vitro release kinetics was best explained by zero-order kinetics and followed Korsemeyer-Pappas model (Non-Fickian mechanism). SEM of F12 revealed the formation of spherical structures. The FTIR study of F12 confirmed the stable nature of ropinirole in the drug-loaded microspheres. DSC and XRD patterns showed that ropinirole hydrochloride was dispersed at the molecular level in the polymer matrix.Conclusion: The controlled release microparticles were successfully prepared and from this study, it was concluded that the developed microspheres of ropinirole hydrochloride can be used for controlled drug release to improve the bioavailability and patient compliance and to maintain a constant drug level in the blood target tissue by releasing the drug in zero order pattern.

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