Skip to main content Accessibility help
×
Home

Organic Biodegradable Aerogels Used in Controlled Drug Release

Published online by Cambridge University Press:  24 March 2011


Anja Veronovski
Affiliation:
University of Maribor, Faculty of Chemistry and Chemical Engineering Smetanova ul. 17, SI-2000 Maribor, Slovenia
Zoran Novak
Affiliation:
University of Maribor, Faculty of Chemistry and Chemical Engineering Smetanova ul. 17, SI-2000 Maribor, Slovenia
Knez Željko
Affiliation:
University of Maribor, Faculty of Chemistry and Chemical Engineering Smetanova ul. 17, SI-2000 Maribor, Slovenia

Abstract

There are a lot of synthetic polymers which can be used for controlled drug delivery, however they are not easily accepted by the organism. Also incorporation of drugs into carriers runs under difficult conditions. Therefore scientists have been inclined to use natural-origin polymers, such as proteins and polysaccharides. Some of these promising natural polysaccharidic candidates are alginic acid sodium salt, guar gum and chitosan due to their outstanding merits. They are similar to extracellular matrix having high chemical versatility, good biological performance and cell or enzyme-controlled degradability. Many polysaccharidic hydrogels for drug delivery have already been prepared, but one of their weakness is their short life in dry air conditions; thus, special coating materials are being developed for enhancing their life time.

Alginates were used in the present research for synthesis of organic biodegradable gels by sol-gel process, which were further easily converted to aerogels by supercritical drying. They are safe for use, nontoxic, and derived from renewable sources. Aerogels made of alginate are dry and stable materials, which makes them interesting as a substitute to hydrogels. Alginates undergo reversible gelation in aqueous solution through interaction with divalent cations such as Ca2+, which create ionic inter-chain bridges. Two fundamental methods of ionic cross-linking were used to prepare alginate hydrogels: the diffusion method, where spheres are created and the internal setting method resulting in monoliths. After producing the hydrogel, alcogels were formed by solvent exchange using 100% ethanol. Ethanol was later replaced by supercritical CO2 with supercritical drying (100 bar, 35°C). Aerogels made from natural polysaccharides combine both biocharacteristics and aerogel characteristics such as high porosity and specific surface area, which makes them really attractive in drug delivery applications. The aerogels obtained in present research were therefore studied as drug carriers. The effects of the alginate composition and synthesis method on model drug nicotinic acid release were investigated. The results indicated that by using the internal setting cross-linking method for obtaining aerogels nicotinic acid was released in a more controlled manner. That is why further investigation was done on alginate spherical beads for prolonging their drug release. A multi-step sol-gel process was applied to generate complex aerogels with multi-membranes. First ionically cross-linked spherical cores were obtained by dropwise addition of sodium alginate solution into a CaCl2 solution. These cores were further immersed into alginate solution, filtered through a sieve and dropped into a salt solution again. By repeating the above process, different multi-membrane hydrogels were produced and further converted to aerogels. By adding more membranes around core burst drug release was successfully inhibited.


Type
Research Article
Copyright
Copyright © Materials Research Society 2011

Access options

Get access to the full version of this content by using one of the access options below.

References

1. Malafaya, P., Silva, G., Reis, R., Advanced Drug Delivery Reviews 59, 207 (2007).10.1016/j.addr.2007.03.012CrossRefGoogle Scholar
2. Novak, Z., Knez, Ž., Journal of Non-Crystalline Solids 221, 163 (1997).10.1016/S0022-3093(97)00342-6CrossRefGoogle Scholar
3. Liu, Z., Jiao, Y., Wang, Y., Advanced Drug Delivery Reviews 60, 1650 (2008).10.1016/j.addr.2008.09.001CrossRefGoogle Scholar
4. Patil, S., Pharmaceutical Reviews E-journal, 2008.Google Scholar
5. Akhondi, H., Taheri-Nassaj, E., Sarpoolaky, H., Ceramics International 35, 1033 (2009).10.1016/j.ceramint.2008.04.023CrossRefGoogle Scholar
6. Horga, Raluca, Di Renzo, Francesco and Quignard, Françoise, Applied Catalysis A: General 325, 251 (2007).10.1016/j.apcata.2007.02.042CrossRefGoogle Scholar
7. Onofre, F., Wang, Y., Mauromoustakos, A., Carbohydrate Polymers 76, 541 (2009).10.1016/j.carbpol.2008.11.016CrossRefGoogle Scholar
8. Cefali, E., Bova, D. U.S. Patent 6818229, filed October 31, 1997, and issued November 16, 2004.Google Scholar

Full text views

Full text views reflects PDF downloads, PDFs sent to Google Drive, Dropbox and Kindle and HTML full text views.

Total number of HTML views: 0
Total number of PDF views: 12 *
View data table for this chart

* Views captured on Cambridge Core between September 2016 - 1st December 2020. This data will be updated every 24 hours.

Hostname: page-component-6d4bddd689-54zsc Total loading time: 0.371 Render date: 2020-12-01T16:21:49.379Z Query parameters: { "hasAccess": "0", "openAccess": "0", "isLogged": "0", "lang": "en" } Feature Flags last update: Tue Dec 01 2020 15:44:26 GMT+0000 (Coordinated Universal Time) Feature Flags: { "metrics": true, "metricsAbstractViews": false, "peerReview": true, "crossMark": true, "comments": true, "relatedCommentaries": true, "subject": true, "clr": false, "languageSwitch": true }

Send article to Kindle

To send this article to your Kindle, first ensure no-reply@cambridge.org is added to your Approved Personal Document E-mail List under your Personal Document Settings on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part of your Kindle email address below. Find out more about sending to your Kindle. Find out more about sending to your Kindle.

Note you can select to send to either the @free.kindle.com or @kindle.com variations. ‘@free.kindle.com’ emails are free but can only be sent to your device when it is connected to wi-fi. ‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.

Find out more about the Kindle Personal Document Service.

Organic Biodegradable Aerogels Used in Controlled Drug Release
Available formats
×

Send article to Dropbox

To send this article to your Dropbox account, please select one or more formats and confirm that you agree to abide by our usage policies. If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your <service> account. Find out more about sending content to Dropbox.

Organic Biodegradable Aerogels Used in Controlled Drug Release
Available formats
×

Send article to Google Drive

To send this article to your Google Drive account, please select one or more formats and confirm that you agree to abide by our usage policies. If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your <service> account. Find out more about sending content to Google Drive.

Organic Biodegradable Aerogels Used in Controlled Drug Release
Available formats
×
×

Reply to: Submit a response


Your details


Conflicting interests

Do you have any conflicting interests? *