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Development of surface functionalized engineered nanomaterials for biological applications


The main research theme is the design and implementation of novel surface functionalities on engineered nanomaterials, by chemical approach, for biological applications. This project involves (1) the creation of biocompatible nanomaterial systems as drug delivery templates, (2) characterization of physico-chemical properties, (3) assessing colloidal stability study under various conditions (physiological circumstances), (4) discovery of bioactivity (e.g. toxicity, release of drug moiety, etc.) and metabolism (interaction with bio entities inside body) mechanisms, in accordance with (5) measurement method development for qualification/quantification of functionalities, and (6) enhancement of manufacturing efficiency through methodological studies for the particular nanomaterials. For successful achievement of this project, our team is establishing collaborations internally at NIST, with other federal entities and/or academia (in US and overseas) to conduct insightful studies.  Long-term goals involve development of a program for ‘Design and recognition of bioactive nanomaterials as nanomedicines’ which will include (a) invention, (b) metrology development for discovery of physico-chem-biological behaviors, and (c) manufacturing.

Example Studies

2015 AuPEI
Au-PEIs produced by ligand exchange of citrate capped gold nanoparticles with differently structured PEI (MW and branched vs linear) resulted in varying physicochemical properties and colloidal stability.  On the right, ATR-FTIR spectra demonstrates differences in Au-PEI surface chemistry depends on applied PEI.

Tae Joon Cho, et. al, “Unexpected Changes in Functionality and Surface Coverage for Au Nanoparticle PEI Conjugates: Implications for Stability and Efficacy in Biological Systems”, Langmuir, 31, 7673−7683 (2015)

Cartoon depiction of conjugation and complexation steps in processing of AuNP-(dendron), AuNP-(dendron)-(SH-PEG) and cisplatin (PtII) complexed products.

Jiaojie Tan, Tae Joon Cho, et. al, “Surface Modification of Cisplatin-Complexed Gold Nanoparticles and Its Influence on Colloidal Stability, Drug Loading, and Drug Release”, Langmuir, 34, 154−163 (2018)

Created March 28, 2018, Updated May 22, 2018