scholarly journals Determining the Optimal Conditions for the Production by Supercritical CO2 of Biodegradable PLGA Foams for the Controlled Release of Rutin as a Medical Treatment

Polymers ◽  
2021 ◽  
Vol 13 (10) ◽  
pp. 1645
Author(s):  
Diego Valor ◽  
Antonio Montes ◽  
Marilia Monteiro ◽  
Ignacio García-Casas ◽  
Clara Pereyra ◽  
...  

Poly(D,L,-lactide-co-glycolide) (PLGA) foam samples impregnated with rutin were successfully produced by supercritical foaming processes. A number of parameters such as pressure (80–200 bar), temperature (35–55 °C), depressurization rate (5–100 bar/min), ratio lactide:glycolide of the poly(D,L,-lactide-co-glycolide) (50:50 and 75:25) were studied to determine their effect on the expansion factor and on the glass transition temperature of the polymer foams and their consequences on the release profile of the rutin entrapped in them. The impregnated foams were characterized by scanning electron microscopy, differential scanning calorimetry, and mercury intrusion porosimetry. A greater impregnation of rutin into the polymer foam pores was observed as pressure was increased. The release of rutin in a phosphate buffer solution was investigated. The controlled release tests confirmed that the modification of certain variables would result in considerable differences in the drug release profiles. Thus, five-day drug release periods were achieved under high pressure and temperature while the depressurization rate remained low.

2017 ◽  
Vol 757 ◽  
pp. 78-82 ◽  
Author(s):  
Weenawan Somphon ◽  
Siriporn Samnaree

This work prepared and characterized of chitosan (Cs)-gelatin (Gel) films for the controlled release of the nitrofurantoin (NF) antibacterial drug. The side effects of NF are nausea and emesis due to its high absorption rate immediately after oral administration. The use of Cs-Gel films enables economic production of the drug carrier system. Cs-Gel films were prepared by mixing Cs with Gel at different ratios and were cross-linked with Na2SO4 with different concentrations. NF was loaded into the films by soaking of drug solution. Films were characterized by Fourier transform infrared spectroscopy (FT-IR), differential scanning calorimetry (DSC) and evaluated for thickness, water absorption capacity, swelling behaviour and invitro NF drug release in phosphate buffer solution pH 5.8 and pH 7.4. The results indicated that additional amount of gelatin and sulfate ion cross-linked to the films increased the swelling, water absorption ability and also improved NF release.


Gels ◽  
2021 ◽  
Vol 7 (3) ◽  
pp. 110
Author(s):  
Muhammad Suhail ◽  
Chih-Wun Fang ◽  
Arshad Khan ◽  
Muhammad Usman Minhas ◽  
Pao-Chu Wu

The purpose of the current investigation was to develop chondroitin sulfate/carbopol-co-poly(acrylic acid) (CS/CBP-co-PAA) hydrogels for controlled delivery of diclofenac sodium (DS). Different concentrations of polymers chondroitin sulfate (CS), carbopol 934 (CBP), and monomer acrylic acid (AA) were cross-linked by ethylene glycol dimethylacrylate (EGDMA) in the presence of ammonium peroxodisulfate (APS) (initiator). The fabricated hydrogels were characterized for further experiments. Characterizations such as Scanning electron microscopy (SEM), Thermogravimetric analysis (TGA), Differential scanning calorimetry (DSC), Powder X-ray diffractometry (PXRD), and Fourier transform infrared spectroscopy (FTIR) were conducted to understand the surface morphology, thermodynamic stability, crystallinity of the drug, ingredients, and developed hydrogels. The swelling and drug release studies were conducted at two different pH mediums (pH 1.2 and 7.4), and pH-dependent swelling and drug release was shown due to the presence of functional groups of both polymers and monomers; hence, greater swelling and drug release was observed at the higher pH (pH 7.4). The percent drug release of the developed system and commercially available product cataflam was compared and high controlled release of the drug from the developed system was observed at both low and high pH. The mechanism of drug release from the hydrogels followed Korsmeyer–Peppas model. Conclusively, the current research work demonstrated that the prepared hydrogel could be considered as a suitable candidate for controlled delivery of diclofenac sodium.


2010 ◽  
Vol 148-149 ◽  
pp. 1427-1430 ◽  
Author(s):  
Kui Lin Deng ◽  
Li Rong Dong ◽  
Yu E Shi ◽  
Yu Bo Gou ◽  
Qian Li ◽  
...  

As a drug delivery carrier, a novel pH/temperature sensitive bead (pTSB) with core-shelled structure from poly(N-acryloylglycine) (PAG), copoly(N-acryloylglycine methyl este and N-acryloylglycine ethyl ester) was prepared by two steps. In pH=7.4 phosphate buffer solution (PBS), the cumulative release amount of indomethacin loaded in the pTSB was about 60.1 % within 500 mins, but this value only reached to 22.3 % in pH=2.1 PBS. The release behaviors of indomethacin from pTSB also exhibited a remarkable dependence on PAG content in the core. Additionally, the release rate of indomethacin was much faster at 18 oC than that at 37 oC due to the temperature sensitivity of poly(N-acryloylglycinates). The experimental results indicate that pTSB seems to have a potential application in the drug release system controlled via pH or temperature in the biomedical fields.


e-Polymers ◽  
2005 ◽  
Vol 5 (1) ◽  
Author(s):  
Chunxue Zhang ◽  
Xiaoyan Yuan ◽  
Lili Wu ◽  
Jing Sheng

AbstractSubmicron poly(vinyl alcohol) (PVA) fibre mats embedded with Aspirin and bovine serum albumin (BSA) were prepared by electrospinning of their aqueous solutions. Fibre morphology was investigated by scanning electron microscopy. The composition of the fibre mats was characterized by Fourier transform IR spectroscopy and X-ray photoelectron spectroscopy. The in vitro drug release was investigated by immersing the fibre mats in phosphate buffer solution at 37°C. Results indicated that the morphology of fibre mats was influenced by the amount of drug, and more beaded and irregularly shaped fibres were found with increasing drug amounts. There were drug molecules distributed on the surface of the PVA fibres. Studies of in vitro drug release showed that both Aspirin and BSA were released more quickly from PVA fibre mats than from PVA films because of the large surface area and high porosity of the fibre mats.


INDIAN DRUGS ◽  
2013 ◽  
Vol 50 (10) ◽  
pp. 30-38
Author(s):  
S Vidyadhara ◽  
◽  
R. L. C. Sasidhar ◽  
P Thrilochani ◽  
L. K. Lavanya

The present investigation was focused on the development and evaluation of controlled release pellets of losartan potassium with Eudragit S 100 and hydroxypropyl methyl cellulose phthalate (HPMCP) by employing pan coating technique. Eudragit S 100, a high viscosity grade controlled release polymer, was mainly used as coating agent for regulating the drug release from pellets. HPMCP, an enteric coating polymer was used in the present study to regulate the drug release at varied G.I. pH conditions. The prepared pellets were evaluated for particle size, drug content, friability and for in vitro drug release. The formulations were further characterized to identify any possible interactions by FTIR spectroscopy and differential scanning calorimetry. The surface morphology of the pellets was studied by scanning electron microscopy. From the results it was observed that due to increase in the concentration of Eudragit the drug release was extended up to 12 hours. The increase in the HPMCP polymeric concentration in formulations showed initial delay in drug release.


2018 ◽  
Vol 5 (1) ◽  
pp. 1 ◽  
Author(s):  
Jessica Oliveira ◽  
Raquel Rodrigues ◽  
Lillian Barros ◽  
Isabel Ferreira ◽  
Luís Marchesi ◽  
...  

In this study, hydrophilic magnetic nanoparticles were synthesized by green routes using a methanolic extract of Rubus ulmifolius Schott flowers. The prepared magnetic nanoparticles were coated with carbon-based shell for drug delivery application. The nanocomposites were further chemically functionalized with nitric acid and, sequentially, with Pluronic® F68 (CMNPs-plur) to enhance their colloidal stability. The resulting material was dispersed in phosphate buffer solution at pH 7.4 to study the Doxorubicin loading. After shaking for 48 h, 99.13% of the drug was loaded by the nanocomposites. Subsequently, the drug release was studied in different working phosphate buffer solutions (i.e., PB pH 4.5, pH 6.0 and pH 7.4) to determine the efficiency of the synthesized material for drug delivery as pH-dependent drug nanocarrier. The results have shown a drug release quantity 18% higher in mimicking tumor environment than in the physiological one. Therefore, this study demonstrates the ability of CMNPs-plur to release a drug with pH dependence, which could be used in the future for the treatment of cancer "in situ" by means of controlled drug release.


2013 ◽  
Vol 22 ◽  
pp. 31-40
Author(s):  
Jin Qiao Xu ◽  
Hai Xing Xu ◽  
Zubad Newaz ◽  
Ran Li ◽  
Yu Zhang ◽  
...  

A new method of reversible association of melphalan (MEL) to magnetic Fe3O4 nanoparticles preparing MEL magnetic microspheres was developed for magnetically targeted chemotherapy. The efficacy of this approach was evaluated in terms of encapsulation efficiency (EE), drug loading content (DLC), delivery properties and cytotoxicity in vitro. Magnetic Fe3O4 nanoparticles were synthesized by co-precipitation methods and characterized by X-ray diffraction (XRD), fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM) and magnetization measurements. The MEL magnetic microspheres were obtained through emulsion cross-linking method and characterized by FTIR, magnetization measurements and scan electron microscopy (SEM). The EE and DLC were determined using a Spectro Vision DB-18805 spectrophotometer. The MEL magnetic microspheres showed good EE values, between 60.6% and 75.6%, as well as good DLC values, between 16.7% and 32.2%, and the magnetic properties were not significantly affected by incorporation of the drug. The in vitro drug release study was carried out in phosphate buffer solution (PBS), simulating physiologic body fluid conditions at 37o C with pH = 7.4. The release profiles showed an initial fast release rate, which decreased as time progressed; about 60% of the drug was released in the first 4 h, and about 78.23 % had been released after 24 h. The results indicated that the prepared magnetic microspheres may be useful for potential applications of MEL for magnetically targeted chemotherapy.


2013 ◽  
Vol 785-786 ◽  
pp. 493-497
Author(s):  
Yu Ping Li ◽  
Li Zhen Sun ◽  
Xiang Yuan Xiong ◽  
Zi Ling Li ◽  
Ting Kang Xing ◽  
...  

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.


2014 ◽  
Vol 12 (7) ◽  
pp. 788-795 ◽  
Author(s):  
Raul-Augustin Mitran ◽  
Daniela Berger ◽  
Laura Băjenaru ◽  
Silviu Năstase ◽  
Cristian Andronescu ◽  
...  

AbstractA light-responsive material, aminoazobenzene functionalized AlMCM-41, was synthesized and characterized in order to be used as carrier for drug delivery devices. The light-induced hydrophobic-hydrophilic switching effect of azobenzene functionalized aluminosilicate was exploited in the release of irinotecan, a cytostatic drug. To obtain the functionalized mesoporous support, an azobenzene-silane precursor was synthesized by coupling 4-(4′-aminophenylazo) benzoic acid with 3-aminopropyl triethoxysilane and further grafted on AlMCM-41. The azobenzene functionalized mesoporous aluminosilicate exhibited no significant toxicity towards murine fibroblast healthy cells and a reduced toxicity towards murine melanocyte cells. The hybrid materials obtained by loading irinotecan on AlMCM-41 (wt. 35.4%) and aminoazobenzene modified AlMCM-41 (wt. 22%), respectively were characterized by FTIR, small and wide angle XRD, N2 adsorption-desorption isotherms and DSC analyses. A two-fold increase in the drug release rate from azobenzene functionalized aluminosilicate in phosphate buffer solution under UV irradiation was noticed, as compared with dark conditions. Moreover, the azobenzene functionalization of AlMCM-41 significantly increased the irinotecan delivery rate and total cumulative release in comparison with the pristine AlMCM-41 in similar conditions.


2015 ◽  
Vol 2015 ◽  
pp. 1-14 ◽  
Author(s):  
Manjanna Kolammanahalli Mallappa ◽  
Rajesh Kesarla ◽  
Shivakumar Banakar

The aim of the present study was to formulate and investigate the calcium alginate- (CA-) Neusilin US2 nanocomposite microbeads containing preconcentrate of aceclofenac sodium (ACF-Na) liquid microemulsion (L-ME) for enhancement of oral bioavailability. The preconcentrate L-ME is prepared by using Labrafac PG, Labrasol, and Span 80 as oil, surfactant, and cosurfactant, respectively. The solid CA nanocomposite microbeads of L-ME prepared by microemulsification internal gelation technique using sodium alginate (SA) gelling agent, Neusilin US2 as adsorbent, and calcium chloride as crosslinking agent. L-ME has good thermodynamic stability; globule size was found to be 32.4 nm with polydispersity index 0.219 and −6.32 mV zeta potential. No significant interactions of excipients, drug in the formulations observed by FT-IR, DSC and XPRD. The concentration of SA and Neusilin US2 influences the flow properties, mean particle size, mechanical strength, drug entrapment efficiency, and percentage of drug release. All the formulations show minimum drug release in simulated gastric fluid (SGF) pH 1.2 for initial 2 h, maximum drug release in pH 6.8 phosphate buffer solution (PBS) at 6 h, followed by sustaining in simulated intestinal fluid (SIF) of pH 7.4 up to 12 h. The interaction of SA with Neusilin US2 creates a thick thixotropic gel network structure which acts as barrier to control the release of drug in the alkaline pH environment. Neusilin US2 is a novel filler used to convert L-ME into solid nanocomposite microbeads to enhance dissolution rate of poor water soluble drugs sustaining the drug release for prolonged period of time.


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