Mn-Doped Quinary Ag–In–Ga–Zn–S Quantum Dots for Dual-Modal Imaging

Abstract

Doping of transition metals within a semiconductor quantum dot (QD) has a high impact on the optical and magnetic properties of the QD. In this study, we report the synthesis of Mn2+-doped Ag–In–Ga–Zn–S (Mn:AIGZS) QDs via thermolysis of a dithiocarbamate complex of Ag+, In3+, Ga3+, and Zn2+ and of Mn­(stearate)2 in oleylamine. The influence of the Mn2+ loading on the photoluminescence (PL) and magnetic properties of the dots are investigated. Mn:AIGZS QDs exhibit a diameter of ca. 2 nm, a high PL quantum yield (up to 41.3% for a 2.5% doping in Mn2+), and robust photo- and colloidal stabilities. The optical properties of Mn:AIGZS QDs are preserved upon transfer into water using the glutathione tetramethylammonium ligand. At the same time, Mn:AIGZS QDs exhibit high relaxivity (r 1 = 0.15 mM–1 s–1 and r 2 = 0.57 mM–1 s–1 at 298 K and 2.34 T), which shows their potential applicability for bimodal PL/magnetic resonance imaging (MRI) probes.

Review of Mn-Doped Semiconductor Nanocrystals for Time-Resolved Luminescence Biosensing/Imaging

“…Although all aforementioned papers focused on the development of Mn-doped NCs toward achieving the desired optical features as discussed in the Introduction, it should be noted that there are many studies using Mn doping to tune the NC luminescence in a wide-wavelength range (from yellow to red to NIR) − or to achieve NCs with double emission peaks covering green to red for the application of photovoltaic devices (e.g., LEDs). − Although the exact luminescence mechanisms still need to be investigated further, the Mn–Mn coupling and interaction between Mn and host NCs still can be applied to explain unique luminescence properties in these studies, as discussed by many researchers in their own studies. Generally, it was observed that Mn-doped NCs with emission color tuning presented short lifetimes in the range of several microseconds to tens or hundreds of microseconds.…”

Hybridized quantum dot, silica, and gold nanoparticles for targeted chemo-radiotherapy in colorectal cancer theranostics

“…2i, l ). The hysteresis curve of VSM results and the paramagnetic properties of QD and QD@MSN were clearly confirmed with their increased magnetization (Ms) by high magnetic field 44 , 45 . In order to confirm that Gd and Au content was sufficient to produce contrast in an MR and CT image, the same serial concentrations of nanoparticles were assessed (Fig.…”

Biosynthesis of Quantum Dots and Their Therapeutic Applications in the Diagnosis and Treatment of Cancer and SARS-CoV-2

“…Accordingly, QDs have been proposed to increase the resolution of these imaging techniques. 83 In other words, bioimaging by QDs is based on the identification of the specific biomarkers of cancer cells and is divided into in-vitro and in-vivo categories. In in-vitro bioimaging, numerous studies have been considered to develop the use of QDs to image the cancer cells of melanoma, ovary, breast, pancreatic, glioblastoma, ovarian epidermoid, lung, hepatocellular, and adenocarcinoma.…”