scholarly journals Furazolidone Immobilized in a Hydrogel Based on Crosslinked Carboxymethyl Cellulose

2017 ◽  
Vol 4 (2) ◽  
pp. 119
Author(s):  
Popa Marcel ◽  
Balaita Rusu Lacramiora ◽  
Sunel Valeriu ◽  
Bajan Nicu
Keyword(s):  
Controlled Release ◽  
Biologically Active ◽  
Active Principle ◽  
Time Interval ◽  
Crosslinking Reaction ◽  
Water Mixture ◽  
Order Kinetic ◽  
Buffer Solution ◽  
Crosslinking Degree

The paper deals with the obtainment of a polymer-drug system with controlled release of the biological active principle, based on furazolidone included in a hydrogel obtained by crosslinking of carboxymethylcellulose with epichlorohydrine. The influence of temperature and duration of crosslinking reaction on the<br />crosslinking degree of carboxymethylcellulose (indirectly appreciated by its swelling capacity in polar liquids as water and dimethylformamide/water mixtures) is studied. Kinetic data concerning the inclusion of furazolidone from solution, in the hydrogel of crosslinked carboxymethylcellulose, as well as the release of the drug from the obtained polymer-drug system, are performed. The obtained results evidence that the inclusion<br />rate as well as the amount of furazolidone diffused into the support depend on the dymethylformamide/water ratio utilized as solvent, and on the drug concentration in solution. The product obtained through the insertion of furazolidone from a DMF/water mixture = 5/1 (with a content of 8.9 mg drug/hydrogel) was studied as to the kinetics of the active principle’s release, in vitro, by using as an eluent a buffer solution, which simulates the gastric fluid (pH = 2.4). The experimental results prove the obtention of a polymerdrug system with controlled release of the biologically active principle, conform to a zero order kinetic, in the time interval ranging between 3–12 hours.

Crosslinked α,β-Polyasparthydrazide Micromatrices for Controlled Release of Anticancer Drugs

1995 ◽  
Vol 10 (1) ◽  
pp. 28-40 ◽  
Author(s):  
Gaetano Giammona ◽  
Giovanna Pitarresi ◽  
Bianca Carlisi ◽  
Gennara Cavallaro
Keyword(s):  
Anticancer Agents ◽  
Crosslinking Agent ◽  
In Vitro Release ◽  
Peroral Administration ◽  
Crosslinking Reaction ◽  
Buffer Solution ◽  
Crosslinking Degree ◽  
Release Studies ◽  
Vitro Release

The preparation of new hydrogels by the reaction of α,β- polyasparthydrazide and glutaraldehyde is reported. A different crosslinking degree was obtained by varying the ratio crosslinking agent/polymer which influenced the swelling behavior of the gel. 5-Fluorouracil, was incorporated into the matrices during the crosslinking reaction and in vitro release studies were performed in simulated gastric juice (pH 1.1) and pH 7.4 buffer solution. The hydrogels prepared were chemically stable in the dissolution media. The observed data show the potential application of these new matrices for peroral administration of anticancer agents.

Controlled Release Characteristics of PLA-Pluronic-PLA Nano-Sized Vesicles In Vitro

2013 ◽  
Vol 785-786 ◽  
pp. 493-497
Author(s):  
Yu Ping Li ◽  
Li Zhen Sun ◽  
Xiang Yuan Xiong ◽  
Zi Ling Li ◽  
Ting Kang Xing ◽  
...  
Keyword(s):  
Controlled Release ◽  
Protein Delivery ◽  
Phosphate Buffer Solution ◽  
Entrapment Efficiency ◽  
Poly Lactic Acid ◽  
Oral Insulin ◽  
Buffer Solution ◽  
The Mean ◽  
The Stability

In the present study, controlled release characteristics of new nanosized PLA-Pluronic-PLA block copolymer vesicles comprising of amphiphilic poly (lactic acid) (PLA) and Pluronic block copolymers (PEO-PPO-PEO) have been evaluated as an oral insulin carrier. The mean size of vesicles was 78 nm for PLA-F127-PLA and 165 nm for PLA-P85-PLA copolymer. The mean insulin entrapment efficiency was 59.6% for PLA-P85-PLA and 26.4% for PLA-F127-PLA. The in vitro release characteristics of insulin from vesicles exhibited an initial burst in the range of pH 1.2-7.4 dissolution mediums. The presence of PLA-Pluronic-PLA vesicles improved the stability of insulin in the gastrointestinal fluids than that of the phosphate buffer solution (PBS) of insulin. More importantly, the released insulin from the vesicles maintained their biological activity. The results from this studies demonstrated that biodegradable PLA-Pluronic-PLA can self-assemble with insulin, form insulin-encapsulated vesicles, and is good carrier materials for oral insulin/protein delivery.

Anticoagulantly active heparin-like molecules from mast cell-deficient mice

1986 ◽  
Vol 250 (5) ◽  
pp. H879-H888 ◽  
Author(s):  
J. A. Marcum ◽  
J. B. McKenney ◽  
S. J. Galli ◽  
R. W. Jackman ◽  
R. D. Rosenberg
Keyword(s):  
Mast Cell ◽  
Mast Cells ◽  
Enzyme Inhibitor ◽  
Biologically Active ◽  
Time Interval ◽  
Heparin Binding ◽  
Similar Time ◽  
A Minor ◽  
Deficient Mice

To assess the contribution of mast cells to the maintenance of blood fluidity, the hindlimb vasculature of mast cell-deficient mice (W/Wv) and littermates containing normal levels of mast cells (+/+), were perfused with purified human thrombin and antithrombin. Enzyme-inhibitor complex generation within the vasculature was enhanced to a comparable extent for W/Wv and +/+ mice over the uncatalyzed rate, that level of complex produced within a similar time interval in the absence of heparin. Perfusion of purified Flavobacterium heparinase prior to infusion of the hemostatic components, or perfusion of antithrombin modified at the heparin-binding domain, reduced W/Wv and +/+ hindlimb thrombin-antithrombin complex formation to the uncatalyzed rate. To further define the cellular source of the vascular-associated heparin-like molecules, endothelial cells isolated from epididymal fat pads of W/Wv and +/+ mice were grown in vitro. The acceleration of thrombin-antithrombin interactions in the presence of endothelial cell-derived glycosaminoglycans was similar for W/Wv and +/+ mice, was abolished with purified bacterial heparinase, and was expressed to only a minor extent when utilizing modified antithrombin. The biologically active mucopolysaccharides appear to be present on the cell surface.

Photothermal triggered protein release from an injectable polycaprolactone-based microspherical depot

2017 ◽  
Vol 5 (20) ◽  
pp. 3634-3639
Author(s):  
Chunling Ge ◽  
Johan S. Basuki ◽  
Jacinta White ◽  
Ruixia Hou ◽  
Yong Peng ◽  
...  
Keyword(s):  
Controlled Release ◽  
Visible Light ◽  
Protein Release ◽  
Biologically Active

Visible light mediated controlled release of biologically active enzymes was confirmed by released horseradish peroxidase's ability to ameliorate H2O2 cytotoxicity in vitro.

Controlled Release of Naproxen Sodium from Eudragit RS 100 Transdermal Film

1970 ◽  
Vol 3 (1) ◽  
Author(s):  
Masuda Khatun ◽  
SM Ashraful Islam ◽  
Parvin Akter ◽  
Mohiuddin Abdul Quadir ◽  
Md. Selim Reza
Keyword(s):  
Controlled Release ◽  
Drug Release ◽  
Naproxen Sodium ◽  
Diffusion Mechanism ◽  
Active Principle ◽  
Burst Release ◽  
Drug Load ◽  
Eudragit Rs ◽  
Peg 4000

Polymeric films of Eudragit RS 100 were prepared by solvent casting method to explore the possibilities of using this polymer in transdermal therapeutic system (TTS). Naproxen was used as a model drug and incorporated in two different percent loading (8.3 % w/w and 20.8 % w/w of films). Effects of two plasticizers ( PEG 1500 and PEG 4000) and two release modifiers ( PVA and HPMC 15cps) on in vitro drug release from naproxen loaded eudragit RS films were assessed. Drug release was found to be a function of drug load, PEG molecular weight and physico-chemical property of the release modifiers incorporated. At low drug load, highest amount of drug was released from flims containing PEG 1500 (more than 95%). However, a burst release was evident in case of all the experimental batches except that loaded with HPMC 15 cps. With this formulation, more than 75 % of active principle was released after 8 hours while only 12 % of naproxen was liberated in the first hour of dissolution. Increasing drug load, increased the rate and extent of drug release from eudragit RS films; however this effect was minimized when PEG 4000 was used as release modifier. For PEG 1500 loaded films, drug release was decreased with increasing drug concentration in the TTS. Inclusion of PEG in eudragit RS films caused the drug to be released by diffusion (Fickian) kinetics whereas PVA and HPMC containing formulations released drug by diffusion mechanism coupled with erosion. Key words: Naproxen sodium, Eudragit RS 100, Controlled release. Dhaka Univ. J. Pharm. Sci. Vol.3(1-2) 2004 The full text is of this article is available at the Dhaka Univ. J. Pharm. Sci. website

scholarly journals INFLUENCE OF AUXIN ON BIOMASS PRODUCTION AND WITHANOLIDE ACCUMULATION IN ADVENTITIOUS ROOT CULTURE OF INDIAN RENNET: WITHANIA COAGULANS

2017 ◽  
Vol 10 (7) ◽  
pp. 131
Author(s):  
Parameswari Murugesan ◽  
Kalaiselvi Senthil
Keyword(s):  
High Performance ◽  
Large Scale ◽  
Root Culture ◽  
Biologically Active ◽  
Active Principle ◽  
Scale Production ◽  
Biomass Growth ◽  
Withania Coagulans ◽  
Medicinal Value

Objective: Withanolides are the biologically active, principle compound present in Withania coagulans, which is having a high medicinal value and possesses potent therapeutic activity. The present study was attempted with an objective to investigate a biomass growth and withanolide production in in vitro root tissues of W. coagulans.Methods: High-performance thin layer chromatography (HPTLC) often serves as a method for quantification of major withanolides. In the present study, methanolic withanolide extract of in vitro cultured W. coagulans root tissue were carried out using HPTLC. The HPTLC analysis was performed using precoated silica gel aluminum plate (20 cm × 20 cm) 60F254 (E.MERCK, Germany) with mobile phase toluene: ethyl acetate: formic acid (5:5:1).Results: The optimization of different combination and concentration of plant growth regulators (indole-3-butyric acid [IBA] and indole-acetic acid) was used to stimulate the biomass growth and withanolide production. The maximum biomass growth (7.48±0.25 g/dL) was observed in medium with 4.93 μM−1 IBA. The higher amount of withanolide A (204.98±0.87 μg/L DW) and withaferin A (227.15±0.57 μg/L DW) accumulation was recorded in culture grown on half Murashiga-Skoog media supplemented with 4.93 μM−1 and 2.46 μM−1 IBA.Conclusion: We concluded that in vitro-cultured system could provide unique opportunities for large-scale production of pharmaceutically important compound than field grown plants.

scholarly journals DEVELOPMENT AND EVALUATION OF BILAYER TABLETS FOR IMMEDIATE AND CONTROLLED RELEASE OF METFORMIN HYDROCHLORIDE

2017 ◽  
pp. 173-179
Author(s):  
Rablee Saikia ◽  
Bhanu Pratap Sahu
Keyword(s):  
Controlled Release ◽  
Sustained Release ◽  
Effective Treatment ◽  
In Vitro Release ◽  
Immediate Release ◽  
Metformin Hydrochloride ◽  
Wet Granulation ◽  
Time Interval ◽  
Weight Variation

Objective: The purpose of this study was to develop and evaluate bi-layer tablets for the immediate and controlled release of Metformin Hydrochloride for effective treatment of type 2 Diabetes mellitus.Methods: The immediate release layer was prepared by using super disintegrants like cross carmellose sodium, sodium starch glycolate and sustained release layer was prepared by using hydrophilic polymer like HPMC K 100 and PVP. Various proportions of super disintegrants and polymer were used to select the best formulation composition. Bilayer tablet of metformin was prepared by wet granulation method and was evaluated for physical characteristics like hardness, weight variation, and friability. In vitro release of drug was performed in USP type II dissolution test apparatus using phosphate buffer (pH 6.8) as dissolution media and dissolution was continued for 9 h for the sustained release layer. For immediate release layer, readings were recorded in each 10 min time interval for the first 1h.Results: From the obtained result it was found that all the formulations were within the limit of the standard. The hardness was found to be in the ranges from 5.1 to 5.5 kg/cm2, weight variation was in the range 0.53% to 0.83%, friability of all the formulations was within the range (<1%)and percentage of drug content was more than 97%. The drug release of the tablet was in the range of 85%-91% in 9 h.Conclusion: From the result obtained, it is found that the formulation F6 satisfies all the criteria as sustained release tablet for the effective treatment of type 2Diabetes mellitus.  

scholarly journals Plasmonic photothermal release of docetaxel by gold nanoparticles incorporated onto halloysite nanotubes with conjugated 2D8-E3 antibodies for selective cancer therapy

2021 ◽  
Vol 19 (1) ◽  
Author(s):  
Reza Taheri-Ledari ◽  
Wenjie Zhang ◽  
Maral Radmanesh ◽  
Nicole Cathcart ◽  
Ali Maleki ◽  
...  
Keyword(s):  
Gold Nanoparticles ◽  
Hydrogen Bonding ◽  
Controlled Release ◽  
Halloysite Nanotubes ◽  
The Body ◽  
Biologically Active ◽  
Strong Hydrogen Bond ◽  
Photothermal Effect ◽  
Scanning Calorimetry

Abstract Background Applied nanomaterials in targeted drug delivery have received increased attention due to tangible advantages, including enhanced cell adhesion and internalization, controlled targeted release, convenient detection in the body, enhanced biodegradation, etc. Furthermore, conjugation of the biologically active ingredients with the drug-containing nanocarriers (nanobioconjugates) has realized impressive opportunities in targeted therapy. Among diverse nanostructures, halloysite nanotubes (NHTs) with a rolled multilayer structure offer great possibilities for drug encapsulation and controlled release. The presence of a strong hydrogen bond network between the rolled HNT layers enables the controlled release of the encapsulated drug molecules through the modulation of hydrogen bonding either in acidic conditions or at higher temperatures. The latter can be conveniently achieved through the photothermal effect via the incorporation of plasmonic nanoparticles. Results The developed nanotherapeutic integrated natural halloysite nanotubes (HNTs) as a carrier; gold nanoparticles (AuNPs) for selective release; docetaxel (DTX) as a cytotoxic anticancer agent; human IgG1 sortilin 2D8-E3 monoclonal antibody (SORT) for selective targeting; and 3-chloropropyltrimethoxysilane as a linker for antibody attachment that also enhances the hydrophobicity of DTX@HNT/Au-SORT and minimizes DTX leaching in body’s internal environment. HNTs efficiently store DTX at room temperature and release it at higher temperatures via disruption of interlayer hydrogen bonding. The role of the physical expansion and disruption of the interlayer hydrogen bonding in HNTs for the controlled DTX release has been studied by dynamic light scattering (DLS), electron microscopy (EM), and differential scanning calorimetry (DSC) at different pH conditions. HNT interlayer bond disruption has been confirmed to take place at a much lower temperature (44 °C) at low pH vs. 88 °C, at neutral pH thus enabling the effective drug release by DTX@HNT/Au-SORT through plasmonic photothermal therapy (PPTT) by light interaction with localized plasmon resonance (LSPR) of AuNPs incorporated into the HNT pores. Conclusions Selective ovarian tumor targeting was accomplished, demonstrating practical efficiency of the designed nanocomposite therapeutic, DTX@HNT/Au-SORT. The antitumor activity of DTX@HNT/Au-SORT (apoptosis of 90 ± 0.3%) was confirmed by in vitro experiments using a caov-4 (ATCC HTB76) cell line (sortilin expression > 70%) that was successfully targeted by the sortilin 2D8-E3 mAb, tagged on the DTX@HNT/Au. Graphic abstract

scholarly journals Nano-Carriers Based on pH-Sensitive Star-Shaped Copolymers for Drug-Controlled Release

Materials ◽  
2019 ◽  
Vol 12 (10) ◽  
pp. 1610 ◽  
Author(s):  
Wenzhao Jiang ◽  
Jianwei Guo ◽  
Weiqiu Wen ◽  
Yong-Guang Jia ◽  
Sa Liu
Keyword(s):  
Controlled Release ◽  
In Vitro Release ◽  
Chemical Properties ◽  
In Vitro Cytotoxicity ◽  
Ph Sensitive ◽  
Oral Drug ◽  
Time Interval ◽  
Selective Hydrolysis ◽  
Drug Controlled Release

Polymeric nano-carriers are considered as promising tools in biomedical applications due to multiple attractive characteristics including their low toxicity, high loading capacity, controlled drug release capabilities, and highly tunable chemical properties. Here, a series of pH-sensitive star-shaped copolymers, Ad-P[(EMA-co-MAA)-b-PPEGMA]4, was prepared via electron transfer atom radical polymerization (ARGETE ATRP) and selective hydrolysis. These star-shaped copolymers can be self-assembled into micelles (Dh = 150–160 nm) and their critical micelle concentrations (CMC) were estimated to be 3.9–5.0 mg/L. The pH-sensitiveness of the micelles was evidenced by transmission electron microscopy (TEM) and dynamic light scattering (DLS). The maximal paclitaxel (PTX) loading efficiency (DLC) and entrapment efficiency (EE) were 18.9% and 36%, respectively. In vitro release studies revealed that about 19% of the PTX released at an acidic condition of pH 1.2 over 70 h, whereas more than 70% was released within the same time interval at pH 6.8. In vitro cytotoxicity suggested that the low cytotoxicity of the blank micelles, while the PTX-loaded micelles providing the cytotoxicity close to that of free PTX. These results indicated that this novel pH-sensitive nano-carriers have great potential applications for oral drug-controlled release.

scholarly journals Formulation and in vitro Evaluation of Betahistine Dihydrochloride Twice Daily Controlled Release Matrix Tablet

2012 ◽  
Vol 10 (2) ◽  
pp. 93-100
Author(s):  
Asraful Islam ◽  
Shimul Halder ◽  
Sitesh Chandra Bachar
Keyword(s):  
Controlled Release ◽  
Release Kinetics ◽  
Matrix Tablets ◽  
In Vitro Dissolution ◽  
Cube Root ◽  
Matrix Tablet ◽  
Buffer Solution ◽  
Simulated Intestinal Fluid ◽  
Betahistine Dihydrochloride

In order to reduce dosing frequency, a sustained release dosage form of betahistine dihydrochloride was developed as a twice daily controlled release tablet formulation that could be used to decrease vertigo resulted in Meniere's disease for a prolonged time. Six formulations were developed by using Methocel K4M CR, Methocel K15M CR and Methocel K 100 LVCR as single and combinations in different percentage. The tablets were prepared by wet granulation method. Physical properties of betahistine dihydrochloride granules and betahistine dihydrochloride matrix tablets were evaluated. The tablets were characterized for Betahistine Dihydrochloride release in both gastric simulated fluid (0.1 N HCl, pH 1.3) and simulated intestinal fluid (buffer solution pH 6.8). The data     were subjected to different models in order to evaluate their release kinetics and mechanisms. The results of the in vitro dissolution study indicate that most of the formulations showed above 80% of drug release in 12 hours but formulations (F-2 and F-4) met the official specification of release profile. Dissolution data were fitted to zero order equation, Higuchi square root law, Korsmeyer-Peppas model and Hixson-Crowell cube root law as these plots showed the highest value of linearity to evaluate kinetic data. The release of betahistine dihydrochloride was prolonged for 12 hours indicating the usefulness of the formulations for twice daily dosage forms, leading to improve efficacy, controlling the release and better patient compliance.   DOI: http://dx.doi.org/10.3329/dujps.v10i2.11786   Dhaka Univ. J. Pharm. Sci. 10(2): 93-100, 2011 (December)    

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