NOTICE: Due to a lapse in annual appropriations, most of this website is not being updated. Learn more.
Form submissions will still be accepted but will not receive responses at this time. Sections of this site for programs using non-appropriated funds (such as NVLAP) or those that are excepted from the shutdown (such as CHIPS and NVD) will continue to be updated.
An official website of the United States government
Here’s how you know
Official websites use .gov
A .gov website belongs to an official government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.
Liposome-Templated Supramolecular Assembly of Responsive Alginate Nanogels
Published
Author(s)
Jennifer S. Hong, Wyatt N. Vreeland, Silvia H. De Paoli Lacerda, Laurie E. Locascio, Michael Gaitan, Srinivasa R. Raghavan
Abstract
Nanosized gel particles (nanogels) are of interest for a variety of applications, including controlled release of drugs and single-molecule encapsulation. Here, we employ the cores of nanoscale liposomes as reaction vessels to template the assembly of calcium alginate nanogels. For our experiments, a liposome formulation with a high bilayer melting temperature (Tm) is formed with sodium alginate encapsulated within and suspended in an aqueous buffer containing calcium chloride. The entry of divalent calcium ions into the liposomal core to crosslink the alginate chains within is mediated by heating the sample to temperatures in the vicinity of Tm, at which point transbilayer permeability is known to be increased. Subsequently, the lipid bilayer covering the gel is removed by addition of a detergent. The resulting alginate gels have a size distribution consistent with that of the template liposomes (120-200 nm), as confirmed by transmission electron microscopy (TEM) and by multi-angle laser light scattering (MALLS) coupled with asymmetric flow field-flow fractionation (AF4). We have synthesized nanogels of different average sizes by varying the template dimensions, and have demonstrated that the gel size can be further tuned after synthesis by the addition of monovalent salt to the solution.
Hong, J.
, Vreeland, W.
, De Paoli Lacerda, S.
, Locascio, L.
, Gaitan, M.
and Raghavan, S.
(2008),
Liposome-Templated Supramolecular Assembly of Responsive Alginate Nanogels, Langmuir, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=32779
(Accessed October 13, 2025)