John Garner

PolySciTech PLGA-Fluorescein used for nanoparticle tracking and cellular uptake assay

Blog Post created by John Garner on Aug 24, 2015

PolySciTech ( provides a wide variety of biodegradable research polymers. These include fluorescently conjugated PLGA to assist in imaging nanoparticles and other polymer structures by microscopy and other techniques. Recently PolyVivo AV01 (PLGA-Fluorescein) was combined with other polymer to generate a functionalized nanoparticle and the uptake of this particle by cells was monitored. This technique holds promise for cellular delivery of drug payloads which could be used as a means of cancer therapy. Read more:  Park, Joonyoung, Tarsis F. Brust, Hong Jae Lee, Sang Cheon Lee, Val J. Watts, and Yoon Yeo. "Polydopamine-based simple and versatile surface modification of polymeric nano drug carriers." ACS nano 8, no. 4 (2014): 3347-3356.

“Abstract: The surface of a polymeric nanoparticle (NP) is often functionalized with cell-interactive ligands and/or additional polymeric layers to control NP interaction with cells and proteins. However, such modification is not always straightforward when the surface is not chemically reactive. For this reason, most NP functionalization processes employ reactive linkers or coupling agents or involve prefunctionalization of the polymer, which are complicated and inefficient. Moreover, prefunctionalized polymers can lose the ability to encapsulate and retain a drug if the added ligands change the chemical properties of the polymer. To overcome this challenge, we use dopamine polymerization as a way of functionalizing NP surfaces. This method includes brief incubation of the preformed NPs in a weak alkaline solution of dopamine, followed by secondary incubation with desired ligands. Using this method, we have functionalized poly(lactic-co-glycolic acid) (PLGA) NPs with three representative surface modifiers: a small molecule (folate), a peptide (Arg-Gly-Asp), and a polymer [poly(carboxybetaine methacrylate)]. We confirmed that the modified NPs showed the expected cellular interactions with no cytotoxicity or residual bioactivity of dopamine. The dopamine polymerization method is a simple and versatile surface modification method, applicable to a variety of NP drug carriers irrespective of their chemical reactivity and the types of ligands. Keywords: polymeric nanoparticles; drug delivery; surface modification; dopamine polymerization; cell−nanoparticle interactions”

Park, 2014 polydopamine nanoparticles tracked using PLGA-FITC.png