scholarly journals Invitro Photo-Controlled Drug Release System Based on Amphiphilic Linear-Dendritic Diblock Copolymers; Self-Assembly Behavior and Application as Nanocarrier

2011 ◽  
Vol 14 (2) ◽  
pp. 162 ◽  
Author(s):  
Hassan Namazi ◽  
Saeed Jafarirad
Keyword(s):  
Diblock Copolymers ◽  
Uv Light ◽  
Drug Carrier ◽  
In Vitro Release ◽  
Simple Type ◽  
Release Behavior ◽  
Trans Form ◽  
Ability To Act ◽  
Micellar Aggregates ◽  
In Trans

Purpose. A simple type of photoresponsive amphiphilic linear-dendritic diblock copolymer has been synthesized and investigated for its ability to act as a drug carrier. These structures contain hydrophilic polyethylene oxide monomethyl ether (PEOM) as hydrophilic block and carbosiloxane dendritic branches as hydrophobic block grafted by two and six Magneson II as azo chromophore, PEOM-Azo, 2 and PEOM-Azo, 6 respectively. Self-assembling of the amphiphilic macromolecules of PEOM-Azo, 2 and PEOM-Azo, 6, briefly were represented as PEOM-Azo [2, 6], leads to the formation of their micellar aggregates in aqueous media. Method. Their micellar properties such as critical micelle concentration (CMC), aggregation number and thereby total numbers of azo-groups in each micellar aggregates were determined. Also, they were characterized by TEM, SEM and DLS. Results. The unloaded aggregates examined under UV light (366 nm), which were observed to be smaller than 300 nm. The release patterns of the encapsulated drug molecule from these aggregates were investigated as regulated by the PEOM-Azo [2, 6] systems in trans and cis forms. Conclusion. A comparison of the release behavior of the loaded PEOM-Azo [2, 6] systems indicated that the release rate of the encapsulated active molecules from the carriers was slower when the azo moieties were in trans form as compared to that the azo in the cis form. The in vitro release behavior of drug from these polymeric systems represents potential of the carriers for controlled drug delivery. This article is open to POST-PUBLICATION REVIEW. Registered readers (see “For Readers”) may comment by clicking on ABSTRACT on the issue’s contents page.

scholarly journals Formulation and development of metformin-loaded microspheres using Khaya senegalensis (Meliaceae) gum as co-polymer

2020 ◽  
Vol 6 (1) ◽  
Author(s):  
Chukwuebuka H. Ozoude ◽  
Chukwuemeka P. Azubuike ◽  
Modupe O. Ologunagba ◽  
Sejoro S. Tonuewa ◽  
Cecilia I. Igwilo
Keyword(s):  
Controlled Release ◽  
Sodium Alginate ◽  
Release Kinetics ◽  
Drug Carrier ◽  
In Vitro Release ◽  
Entrapment Efficiency ◽  
Metformin Hydrochloride ◽  
Scanning Calorimetry ◽  
Khaya Senegalensis

Abstract Background Khaya gum is a bark exudate from Khaya senegalensis (Maliaecae) that has drug carrier potential. This study aimed to formulate and comparatively evaluate metformin-loaded microspheres using blends of khaya gum and sodium alginate. Khaya gum was extracted and subjected to preformulation studies using established protocols while three formulations (FA; FB and FC) of metformin (1% w/v)-loaded microspheres were prepared by the ionic gelation method using 5% zinc chloride solution as the cross-linker. The formulations contained 2% w/v blends of khaya gum and sodium alginate in the ratios of 2:3, 9:11, and 1:1, respectively. The microspheres were evaluated by scanning electron microscopy, Fourier transform-infrared spectroscopy, differential scanning calorimetry, entrapment efficiency, swelling index, and in vitro release studies. Results Yield of 28.48%, pH of 4.00 ± 0.05, moisture content (14.59% ± 0.50), and fair flow properties (Carr’s index 23.68 ± 1.91 and Hausner’s ratio 1.31 ± 0.03) of the khaya gum were obtained. FTIR analyses showed no significant interaction between pure metformin hydrochloride with excipients. Discrete spherical microspheres with sizes ranging from 1200 to 1420 μm were obtained. Drug entrapment efficiency of the microspheres ranged from 65.6 to 81.5%. The release of the drug from microspheres was sustained for the 9 h of the study as the cumulative release was 62% (FA), 73% (FB), and 80% (FC). The release kinetics followed Korsmeyer-Peppas model with super case-II transport mechanism. Conclusion Blends of Khaya senegalensis gum and sodium alginate are promising polymer combination for the preparation of controlled-release formulations. The blend of the khaya gum and sodium alginate produced microspheres with controlled release properties. However, the formulation containing 2:3 ratio of khaya gum and sodium alginate respectively produced microspheres with comparable controlled release profiles to the commercial brand metformin tablet.

scholarly journals Folate-Functionalized Mesoporous Hollow SnO2 Nanofibers as a Targeting Drug Carrier to Improve the Antitumor Effect of Paclitaxel for Liver Cancer Therapy

2018 ◽  
Vol 2018 ◽  
pp. 1-11
Author(s):  
Huiling Lv ◽  
Chao Wu ◽  
Xuan Liu ◽  
Andi Bai ◽  
Yue Cao ◽  
...  
Keyword(s):  
Cancer Therapy ◽  
Liver Cancer ◽  
Drug Carrier ◽  
In Vitro Release ◽  
Hollow Structure ◽  
Amorphous State ◽  
Outer Diameter ◽  
Drug Delivery Carrier

In this study, we prepared PTX-loaded mesoporous hollow SnO2 nanofibers conjugated with folic acid (SFNFP) for liver cancer therapy. According to SEM and TEM characterization, SFNF showed a mesoporous hollow structure. The average outer diameter was 200 nm, and the wall thickness was 50 nm. The DSC and XRD study showed that PTX in the channels of nanofibers was present in an amorphous state. The in vitro release experiments demonstrated that SFNF could efficiently improve the dissolution rate of PTX. Both in vitro cell experiments and in vivo antitumor experiments showed that SFNFP could efficiently inhibit the growth of liver cancer cells. Therefore, SFNF is a promising targeting antitumor drug delivery carrier.

scholarly journals Regulation of rice root development by a retrotransposon acting as a microRNA sponge

eLife ◽  
2017 ◽  
Vol 6 ◽  
Author(s):  
Jungnam Cho ◽  
Jerzy Paszkowski
Keyword(s):  
Gene Regulation ◽  
Transcription Factors ◽  
Root Development ◽  
Binding Sites ◽  
Transcriptional Control ◽  
Specific Expression ◽  
Ability To Act ◽  
Specific Accumulation ◽  
In Trans ◽  
Microrna Sponge

It is well documented that transposable elements (TEs) can regulate the expression of neighbouring genes. However, their ability to act in trans and influence ectopic loci has been reported rarely. We searched in rice transcriptomes for tissue-specific expression of TEs and found them to be regulated developmentally. They often shared sequence homology with co-expressed genes and contained potential microRNA-binding sites, which suggested possible contributions to gene regulation. In fact, we have identified a retrotransposon that is highly transcribed in roots and whose spliced transcript constitutes a target mimic for miR171. miR171 destabilizes mRNAs encoding the root-specific family of SCARECROW-Like transcription factors. We demonstrate that retrotransposon-derived transcripts act as decoys for miR171, triggering its degradation and thus results in the root-specific accumulation of SCARECROW-Like mRNAs. Such transposon-mediated post-transcriptional control of miR171 levels is conserved in diverse rice species.

scholarly journals Cellulose/guar gum hydrogel microspheres as a magnetic anticancer drug carrier

BioResources ◽  
2019 ◽  
Vol 14 (2) ◽  
pp. 3615-3629 ◽  
Author(s):  
Yanli Li ◽  
Yucheng Feng ◽  
Jun Jing ◽  
Fei Yang
Keyword(s):  
Anticancer Drug ◽  
Guar Gum ◽  
Drug Carrier ◽  
Drug Loading ◽  
In Vitro Release ◽  
Adsorption Effect ◽  
Magnetic Hydrogel ◽  
Vitro Release ◽  
Hydrogel Microspheres

A novel magnetic anticancer drug carrier based on cellulose, guar gum, and Fe3O4 hydrogel microspheres was synthesized by chemical crosslinking. These microspheres were crosslinked with epoxy chloropropane and loaded with 5-fluorouracil (5-fu). The effect of the ratio of cellulose to guar gum on bead size, drug loading, and in vitro release behaviors were investigated. The influence of the magnetic content on drug loading and in vitro release behaviors were also evaluated. The magnetic hydrogel microspheres were characterized via an optical microscope, Fourier transform infrared spectroscopy, swelling behavior analysis, vibrating sample magnetometer, and ultraviolet absorption spectroscopy. The results showed that as the ratio of cellulose to guar gum increased from 3:1 to 5:1, the particle size increased from 395 to 459 um. Moreover, the drug loading capacity, encapsulation efficiency, and in vitro release behavior were influenced by the ratio of cellulose/guar gum and Fe3O4 content. Finally, the Fe3O4 particle had an adsorption effect on the drug, thereby reducing the maximum cumulative release.

Calcium phosphate porous pellets as drug delivery systems: Effect of drug carrier composition on drug loading and in vitro release

2012 ◽  
Vol 32 (11) ◽  
pp. 2679-2690 ◽  
Author(s):  
Hiva Baradari ◽  
Chantal Damia ◽  
Maggy Dutreih-Colas ◽  
Etienne Laborde ◽  
Nathalie Pécout ◽  
...  
Keyword(s):  
Drug Delivery ◽  
Calcium Phosphate ◽  
Drug Delivery Systems ◽  
Drug Carrier ◽  
Drug Loading ◽  
In Vitro Release ◽  
Delivery Systems ◽  
Vitro Release

scholarly journals Analysis of Drug Release Behavior Utilizing the Swelling Characteristics of Cellulosic Nanofibers

Polymers ◽  
2019 ◽  
Vol 11 (9) ◽  
pp. 1376 ◽  
Author(s):  
Sung Won Ko ◽  
Ji Yeon Lee ◽  
Joshua Lee ◽  
Byeong Cheol Son ◽  
Se Rim Jang ◽  
...  
Keyword(s):  
Drug Release ◽  
Uv Spectroscopy ◽  
Drug Carrier ◽  
High Water ◽  
Nanofibrous Membrane ◽  
Release Behavior ◽  
Noticeable Increase ◽  
Drug Release Behavior ◽  
Drug Of Choice ◽  
Swelling Characteristics

It is known that the behavior of a drug released from a supporting carrier is influenced by the surrounding environment and the carrier. In this study, we investigated the drug behavior of a swellable electrospun nanofibrous membrane. Nanofibrous mats with different swelling ratios were prepared by mixing cellulose acetate (CA) and polyurethane (PU). CA has excellent biocompatibility and is capable of high water uptake, while PU has excellent mechanical properties. Paclitaxel (PTX) was the drug of choice for observing drug release behavior, which was characterized by UV-spectroscopy. FE-SEM was used to confirm the morphology of the nanofibrous mats and to measure the average fiber diameters. We observed a noticeable increase in the total volume of the nanofibrous membrane when it was immersed in water. Also, the drug release behavior increased proportionally with increasing swelling rate of the composite nanofibrous mat. Biocompatibility testing of nanofiber materials was confirmed by CCK-8 assay and cell morphology was observed. Based on these results, we propose nanofibrous mats as promising candidates in wound dressing and other drug carrier applications.

Fabrication of curcumin-loaded whey protein microgels: Structural properties, antioxidant activity, and in vitro release behavior

LWT ◽  
2019 ◽  
Vol 103 ◽  
pp. 94-100 ◽  
Author(s):  
Mehdi Mohammadian ◽  
Maryam Salami ◽  
Shima Momen ◽  
Farhad Alavi ◽  
Zahra Emam-Djomeh
Keyword(s):  
Antioxidant Activity ◽  
Whey Protein ◽  
Structural Properties ◽  
In Vitro Release ◽  
Release Behavior ◽  
Vitro Release
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