Pushing indium phosphide quantum dot emission deeper into the near infrared

A. M. Saeboe; J. Kays; A. H. Mahler; A. M. Dennis

doi:10.1117/12.2295370

23 February 2018 Pushing indium phosphide quantum dot emission deeper into the near infrared

A. M. Saeboe, J. Kays, A. H. Mahler, A. M. Dennis

Proceedings Volume 10507, Colloidal Nanoparticles for Biomedical Applications XIII; 1050715 (2018) https://doi.org/10.1117/12.2295370
Event: SPIE BiOS, 2018, San Francisco, California, United States

Abstract

Cadmium-free near infrared (NIR) emitting quantum dots (QDs) have significant potential for multiplexed tissue-depth imaging applications in the first optical tissue window (i.e., 650 – 900 nm). Indium phosphide (InP) chemistry provides one of the more promising cadmium-free options for biomedical imaging, but the full tunability of this material has not yet been achieved. Specifically, InP QD emission has been tuned from 480 – 730 nm in previous literature reports, but examples of samples emitting from 730 nm to the InP bulk bandgap limit of 925 nm are lacking. We hypothesize that by generating inverted structures comprising ZnSe/InP/ZnS in a core/shell/shell heterostructure, optical emission from the InP shell can be tuned by changing the InP shell thickness, including pushing deeper into the NIR than current InP QDs. Colloidal synthesis methods including hot injection precipitation of the ZnSe core and a modified successive ion layer adsorption and reaction (SILAR) method for stepwise shell deposition were used to promote growth of core/shell/shell materials with varying thicknesses of the InP shell. By controlling the number of injections of indium and phosphorous precursor material, the emission peak was tuned from 515 nm to 845 nm (2.41 – 1.47 eV) with consistent full width half maximum (FWHM) values of the emission peak ~0.32 eV. To confer water solubility, the nanoparticles were encapsulated in PEGylated phospholipid micelles, and multiplexing of NIR-emitting InP QDs was demonstrated using an IVIS imaging system. These materials show potential for multiplexed imaging of targeted QD contrast agents in the first optical tissue window.

Conference Presentation

Citation Download Citation

A. M. Saeboe, J. Kays, A. H. Mahler, and A. M. Dennis "Pushing indium phosphide quantum dot emission deeper into the near infrared", Proc. SPIE 10507, Colloidal Nanoparticles for Biomedical Applications XIII, 1050715 (23 February 2018); https://doi.org/10.1117/12.2295370

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available