POLY(VINYLPYRROLIDONE)-CHITOSAN HYDROGELS AS MATRICES FOR CONTROLLED DRUG RELEASE

In this study, hydrogels based on poly(vinylpyrrolidone) and chitosan, derived from different mixing ratios of poly(vinylpyrrolidone)/chitosan, were synthesized by the freeze-drying technique with the aim of obtaining new systems that could be used to release tetracycline hydrochloride (TH). Freeze-drying methods were also used to prepare the hydrogels containing TH. The hydrogels were characterized using Fourier transform infrared spectroscopy and scanning electron microscopy, as well as in terms of dynamic water vapour sorption capacity. The poly(vinylpyrrolidone)/chitosan hydrogels were evaluated with regard to the release of TH. The release profiles of TH from the poly(vinylpyrrolidone)/chitosan hydrogels depended on the chitosan content. It could be seen that if the concentration of chitosan was too high, the release was delayed and not fully achieved, because the release of the drug was prevented by the crystalline areas of the chitosan. According to the release study, the drug release mechanism of the poly(vinylpyrrolidone)/chitosan hydrogels loaded with TH perfectly fitted the Higuchi and the Korsmeyer-Peppas models. The highest value of water vapor sorption capacity was obtained for the hydrogel with the poly(vinylpyrrolidone)/chitosan ratio of 50/50. PVP-CS loaded with 3 wt% TH may potentially be used for the controlled delivery of tetracycline to treat oral infections.

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FABRICATION OF NANO CLAY INTERCALATED POLYMERIC MICROBEADS FOR CONTROLLED RELEASE OF CURCUMIN

International Journal of Applied Pharmaceutics ◽

10.22159/ijap.2021v13i1.39965 ◽

2021 ◽

pp. 206-215

Author(s):

DHARMENDER PALLERLA ◽

SUMAN BANOTH ◽

SUNKARI JYOTHI

Keyword(s):

Drug Release ◽

In Vitro Release ◽

Controlled Drug Release ◽

Fickian Diffusion ◽

Simulated Gastric Fluid ◽

Release Mechanism ◽

Release Studies ◽

Swelling Studies ◽

Vitro Release

Objective: The objective of this study was to formulate and evaluate the Curcumin (CUR) encapsulated sodium alginate (SA)/badam gum (BG)/kaolin (KA) microbeads for controlled drug release studies. Methods: The fabricated microbeads were characterized by fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), X-ray diffraction (X-RD), and scanning electron microscopy (SEM). Dynamic swelling studies and in vitro release kinetics were performed in simulated intestinal fluid (pH 7.4) and simulated gastric fluid (pH 1.2) at 37 °C. Results: FTIR confirms the formation of microbeads. DSC studies confirm the polymorphism of CUR in drug loaded microbeads which indicate the molecular level dispersion of the drug in the microbeads. SEM studies confirmed the microbeads are spherical in shape with wrinkled and rough surfaces. XRD studies reveal the molecular dispersion of CUR and the presence of KA in the developed microbeads. In vitro release studies and swelling studies depend on the pH of test media, which might be suitable for intestinal drug delivery. The % of drug release values fit into the Korsmeyer-Peppas equation and n values are obtained in the range of 0.577-0.664, which indicates that the developed microbeads follow the non-Fickian diffusion drug release mechanism. Conclusion: The results concluded that the CUR encapsulated microbeads are potentially good carriers for controlled drug release studies.

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N-(furfural) chitosan hydrogels based on Diels–Alder cycloadditions and application as microspheres for controlled drug release

Carbohydrate Polymers ◽

10.1016/j.carbpol.2015.03.052 ◽

2015 ◽

Vol 128 ◽

pp. 220-227 ◽

Cited By ~ 46

Author(s):

Marcelino Montiel-Herrera ◽

Alessandro Gandini ◽

Francisco M. Goycoolea ◽

Neil E. Jacobsen ◽

Jaime Lizardi-Mendoza ◽

...

Keyword(s):

Drug Release ◽

Controlled Drug Release ◽

Diels Alder ◽

Chitosan Hydrogels

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Synthesis and Characterization of Lyophilized Chitosan-Based Hydrogels Cross-Linked with Benzaldehyde for Controlled Drug Release

Journal of Chemistry ◽

10.1155/2020/8747639 ◽

2020 ◽

Vol 2020 ◽

pp. 1-10 ◽

Cited By ~ 1

Author(s):

Fouad Damiri ◽

Yahya Bachra ◽

Chaimaa Bounacir ◽

Asmae Laaraibi ◽

Mohammed Berrada

Keyword(s):

Ascorbic Acid ◽

Drug Release ◽

Drug Loading ◽

In Vitro Release ◽

Controlled Drug Release ◽

Tween 20 ◽

Release Mechanism ◽

Synthetic Process ◽

Chitosan Salt

In this study, chitosan-based hydrogels were produced by incorporating three drugs with a different solubility into a polymer matrix. The lyophilized chitosan salt was prepared using an innovative and less-expensive synthetic process by the freeze-drying technique. Firstly, the three drugs (caffeine, ascorbic acid, and 5-fluorouracil (5-FU)) were selected as model drugs to test the in vitro release behavior of the hydrogel. The drugs were solubilized in chitosan salt, lyophilized, and cross-linked with benzaldehyde involving the formation of a Schiff base with (–C=N-) linkage to produce a physical hydrogel. Subsequently, the physicochemical properties of N-benzyl chitosan and lyophilized chitosan salt were evaluated by Fourier-transform infrared (FTIR) spectra, scanning electron microscopy (SEM), and thermogravimetric analysis (TGA). The intrinsic viscosity of the conventional chitosan was determined by the Mark–Houwink–Sakurada equation. Moreover, the kinetics of hydrogel swelling and drug release were studied by the UV-visible method at physiological conditions (pH = 7.4 at 37°C). The results show that lyophilized N-benzyl chitosan had a maximum swelling ratio of 720 ± 2% by immersion in phosphate-buffered saline solutions (PBS) (pH = 7.4 at 37°C). In vitro drug releases were evaluated in PBS, and the obtained results show that the maximum drug release after 24 h was 42% for caffeine, 99% for 5-FU, and 94% for ascorbic acid. Then, to optimize the cumulative release of caffeine, Tween 20 was added and 98% as a release percentage was obtained. The drug-loading results were investigated with the Korsmeyer–Peppas kinetic model and applied to determine the drug release mechanism.

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The Measurement and Mathematical Analysis of 5-Fu Release from Magnetic Polymeric Nanocapsules, following the Application of Ultrasound

Anti-Cancer Agents in Medicinal Chemistry ◽

10.2174/1871520617666170921124951 ◽

2018 ◽

Vol 18 (3) ◽

pp. 438-449 ◽

Cited By ~ 5

Author(s):

Ziaeddin Abed ◽

Samideh Khoei ◽

Behafarid Ghalandari ◽

Jaber Beik ◽

Ali Shakeri-Zadeh ◽

...

Keyword(s):

Drug Release ◽

Mathematical Analysis ◽

Ultrasound Irradiation ◽

Controlled Drug Release ◽

Release Profile ◽

Release Mechanism ◽

Drug Release Profile ◽

Ultrasound Intensity ◽

Dialysis Bag

Objective: To study the effects of ultrasound irradiation on the release profile of 5-fluorouracil (5-Fu) loaded magnetic poly lactic co-glycolic acid (PLGA) nanocapsules. Also, the controlled drug-release behaviour of the nanocapsules was mathematically investigated. Methods: The nanocapsules were synthesized, dispersed in phosphate buffered saline (PBS), transferred to a dialysis bag, and finally, irradiated by various ultrasound parameters (1 or 3MHz; 0.3-1W/cm2; 5-10 minutes). The release profile of the irradiated nanocapsules was recorded for 14 days. To find the in vitro drug release mechanism in the absence and presence of various intensities of ultrasound, the obtained data were fitted in various kinetic models for drug release. Results: The results demonstrated that the ultrasound speeded up the rate of drug release from the nanocapsules. The mathematical analysis illustrated that when the ultrasound intensity is increased, the probability of controlled release behaviour of the nanocapsules is raised. We found that drug release from the irradiated nanocapsules follows an erosion-controlled mechanism with the decrease in the velocity of diffusion. Conclusion: In conclusion, to attain a controlled drug-delivery strategy in the area of cancer therapy, the drug release profile of the nano-carriers may be well-controlled by ultrasound.

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Reduction-Responsive Molecularly Imprinted Poly(2-isopropenyl-2-oxazoline) for Controlled Release of Anticancer Agents

Pharmaceutics ◽

10.3390/pharmaceutics12060506 ◽

2020 ◽

Vol 12 (6) ◽

pp. 506 ◽

Cited By ~ 1

Author(s):

Michał Cegłowski ◽

Valentin Victor Jerca ◽

Florica Adriana Jerca ◽

Richard Hoogenboom

Keyword(s):

Controlled Release ◽

Drug Release ◽

Anticancer Agents ◽

Release Kinetics ◽

Controlled Drug Release ◽

Release Mechanism ◽

Molecularly Imprinted ◽

Responsive Materials ◽

Future Work ◽

Specific Trigger

Trigger-responsive materials are capable of controlled drug release in the presence of a specific trigger. Reduction induced drug release is especially interesting as the reductive stress is higher inside cells than in the bloodstream, providing a conceptual controlled release mechanism after cellular uptake. In this work, we report the synthesis of 5-fluorouracil (5-FU) molecularly imprinted polymers (MIPs) based on poly(2-isopropenyl-2-oxazoline) (PiPOx) using 3,3′-dithiodipropionic acid (DTDPA) as a reduction-responsive functional cross-linker. The disulfide bond of DTDPA can be cleaved by the addition of tris(2-carboxyethyl)phosphine (TCEP), leading to a reduction-induced 5-FU release. Adsorption isotherms and kinetics for 5-FU indicate that the adsorption kinetics process for imprinted and non-imprinted adsorbents follows two different kinetic models, thus suggesting that different mechanisms are responsible for adsorption. The release kinetics revealed that the addition of TCEP significantly influenced the release of 5-FU from PiPOx-MIP, whereas for non-imprinted PiPOx, no statistically relevant differences were observed. This work provides a conceptual basis for reduction-induced 5-FU release from molecularly imprinted PiPOx, which in future work may be further developed into MIP nanoparticles for the controlled release of therapeutic agents.

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Weibull Modeling of Controlled Drug Release from Ag-PMA Nanosystems

Polymers ◽

10.3390/polym13172897 ◽

2021 ◽

Vol 13 (17) ◽

pp. 2897

Author(s):

Carmelo Corsaro ◽

Giulia Neri ◽

Angela Maria Mezzasalma ◽

Enza Fazio

Keyword(s):

Drug Release ◽

Controlled Drug Release ◽

Drug Carriers ◽

Polymer Chains ◽

Patient Treatment ◽

Release Mechanism ◽

Release Process ◽

Precise Control ◽

Biochemical Processes ◽

Drug Selectivity

Traditional pharmacotherapy suffers from multiple drawbacks that hamper patient treatment such as antibiotic resistances or low drug selectivity and toxicity during systemic applications. Some functional hybrid nanomaterials are designed to handle the drug release process under remote-control. More attention has recently been paid to synthetic polyelectrolytes for their intrinsic properties which allow them to rearrange into compact structures, ideal to be used as drug carriers or probes influencing biochemical processes. The presence of Ag nanoparticles (NPs) in the Poly methyl acrylate (PMA) matrix leads to an enhancement of drug release efficiency, even using a low-power laser whose wavelength is far from the Ag Surface Plasmon Resonance (SPR) peak. Further, compared to the colloids, the nanofiber-based drug delivery system has shown shorter response time and more precise control over the release rate. The efficiency and timing of involved drug release mechanisms has been estimated by the Weibull distribution function, whose parameters indicate that the release mechanism of nanofibers obeys Fick’s first law while a non-Fickian character controlled by diffusion and relaxation of polymer chains occurs in the colloidal phase.

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Linear-g-hyperbranched and cyclodextrin-based amphiphilic block copolymer as a multifunctional nanocarrier

Beilstein Journal of Organic Chemistry ◽

10.3762/bjoc.10.284 ◽

2014 ◽

Vol 10 ◽

pp. 2696-2703 ◽

Cited By ~ 2

Author(s):

Yamei Zhao ◽

Wei Tian ◽

Guang Yang ◽

Xiaodong Fan

Keyword(s):

Drug Release ◽

Drug Loading ◽

Controlled Drug Release ◽

Release Mechanism ◽

The Novel ◽

Reversible Addition ◽

Diagnostic Agents ◽

Triblock Polymer ◽

One Step ◽

Multifunctional Nanocarriers

In this paper, a novel, multifunctional polymer nanocarrier was designed to provide adequate volume for high drug loading, to afford a multiregion encapsulation ability, and to achieve controlled drug release. An amphiphilic, triblock polymer (ABC) with hyperbranched polycarbonsilane (HBPCSi) and β-cyclodextrin (β-CD) moieties were first synthesized by the combination of a two-step reversible addition-fragmentation transfer polymerization into a pseudo-one-step hydrosilylation and quaternization reaction. The ABC then self-assembled into stable micelles with a core–shell structure in aqueous solution. These resulting micelles are multifunctional nanocarriers which possess higher drug loading capability due to the introduction of HBPCSi segments and β-CD moieties, and exhibit controlled drug release based on the diffusion release mechanism. The novel multifunctional nanocarrier may be applicable to produce highly efficient and specialized delivery systems for drugs, genes, and diagnostic agents.

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Polyelectrolyte Complex Based Nanocapsules Carrying Novel 5-Nitroindazole Thiazolidines with Potential Use in Treating Oral Infections

Materiale Plastice ◽

10.37358/mp.17.1.4808 ◽

2017 ◽

Vol 54 (1) ◽

pp. 160-167

Author(s):

Toni Andor Cigu ◽

Mihaela Nicoleta Holban ◽

Anca Niculina Cadinoiu ◽

Valeriu Sunel ◽

Catalina Lionte ◽

...

Keyword(s):

Drug Release ◽

Salmonella Enteritidis ◽

Controlled Drug Release ◽

Bacterial Strains ◽

Oral Infections ◽

Chemical Structures ◽

Particle Stability ◽

Eudragit E100 ◽

And Staphylococcus Aureus ◽

Potential Use

The aim of this research was the synthesis of novel 2,3-disubstituted 1,3 thiazolidines, derived from 5-nitroindazole with antimicrobial activity and their encapsulation into polymer nanocapsules. Starting from previously synthesised hydrazones, there have been obtained novel thiazolidines by reaction with thioglycolic acid. The envisaged chemical structures were confirmed by spectral and elemental analysis. Two of the obtained thiazolidines were encapsulated into cationic Eudragit E100 nanocapsules, obtained by nanoprecipitation. In order to enhance drug release characteristics and particle stability, Eudragit E100 nanocapsules were covered with anionic polysaccharide (sodium alginate), thus forming a complex polyelectrolyte based membrane. The obtained nanocapsules presented a slower and more controlled drug release. The synthesized active principles, in free state and encapsulated into polymer nanocapsules, were tested for their acute toxicity and their influence on the development of model bacterial strains (Staphylococcus mutans, Actinobacillus actinomycetemcomitans, Bacillus subtilis, Bacillus cereus, Salmonella enteritidis, Escherichia coli and Staphylococcus aureus).

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