Description:
Reference #: 01041
The University of South Carolina is offering licensing opportunities for this novel method of purifying nanocrystals.
Invention Description:
The invention introduces a highly precise and effective gel permeation chromatography (GPC) purification technique, which can be used to prepare colloidal quantum dots (QDs) with well-defined surface characteristics. The inventors have found that it removes impurities that are not removed by a commonly used precipitation and redissolution methods that depend on solubility. Examples are presented for CdSe QDs and CdSe/CdxZn1-xS core/shell QDs that absorb and emit visible light and are representative of QDs with potential for applications in solar energy, opto-electronic, and biomedical imaging applications.
Advantages and Benefits:
This invention will aid, for example, vendors of QDs and QD-derived imaging agents by providing a scalable and repeatable, preparative technique, and via the products of such purification, well-defined benchmarks with which to characterize subsequent chemical reactions and measurements of physical properties.
Background:
The traditional method for purification of QDs is a sequential precipitation and redissolution (PR) process. In the PR process, QDs are precipitated from a solution mixture by introducing anti-solvents. Polarity is an essential factor in the precipitation of QDs; however, due to its variance among different QD batches and uncertainty as to the solubility characteristics of undesired impurities and/or excess ligands, it is an unreliable property on which to base the isolation of QDs.
Potential Applications:
The mobile phase for the size-based, GPC purification technique can be an organic solvent in which the QDs remain miscible, and therefore affords a single-phase purification that does not risk disturbing the original binding environment. Furthermore, some QD samples can present solubility limitations after multiple precipitations, which are amply circumvented by the GPC purification technique.