Stable nanoconjugates of transferrin with alloyed quaternary nanocrystals Ag–In–Zn–S as a biological entity for tumor recognition

Abstract

One way to limit the negative effects of anti-tumor drugs on healthy cells is targeted therapy employing functionalized drug carriers. Here we present a biocompatible and stable nanoconjugate of transferrin anchored to Ag-In-Zn-S quantum dots modified with 11-mercaptoundecanoic acid (Tf-QD) as a drug carrier versus typical anticancer drug, doxorubicin. Detailed investigations of Tf-QD nanoconjugates without and with doxorubicin by fluorescence studies and cytotoxic measurements showed that the biological activity of both the transferrin and doxorubicin was fully retained in the nanoconjugate. In particular, the intercalation capabilities of free doxorubicin versus ctDNA remained essentially intact upon its binding to the nanoconjugate. In order to evaluate these capabilities, we studied the binding constant of doxorubicin attached to Tf-QDs with ctDNA as well as the binding site size on the ctDNA molecule. The binding constant slightly decreased compared to that of free doxorubicin while the binding site size, describing the number of consecutive DNA lattice residues involved in the binding, increased. It was also demonstrated that the QDs alone and in the form of a nanoconjugate with Tf were not cytotoxic towards human non-small cell lung carcinoma (H460 cell line) and the tumor cell sensitivity of the DOX-Tf-QD nanoconjugate was comparable to that of doxorubicin alone.

From Red to Green Luminescence via Surface Functionalization. Effect of 2-(5-Mercaptothien-2-yl)-8-(thien-2-yl)-5-hexylthieno[3,4-c]pyrrole-4,6-dione Ligands on the Photoluminescence of Alloyed Ag–In–Zn–S Nanocrystals

“…This type of research is highly desirable in the case of quaternary Ag–In–Zn–S nanocrystals, especially, because by changing their composition it is possible to tune their efficient luminescence over the whole visible spectral range. This strongly facilitates their application in electronics − and biomedical sciences. − The analysis of ligand exchange-induced photoluminescence changes is especially important in this respect. In the case of binary CdSe nanocrystals the luminescence is governed by the classical radiative recombination mechanism 1S­(e) → 1S­(h).…”

Quantum Dots as a Good Carriers of Unsymmetrical Bisacridines for Modulating Cellular Uptake and the Biological Response in Lung and Colon Cancer Cells

“…Fluorometric measurements were performed using Scinco-FS2 spectrofluorometer (Scinco, Seoul, South Korea) with low volume (200 µL) optical cuvette (Product no. 16.100 F/Q/10 from Starna Scientific, Co, Ilford, UK) compatible in terms of size and aperture position with the apparatus.…”

“…QDs are spherical semiconductor NPs with versatile surface chemistry, which can be modulated. They have high potential in various biological applications, including bioimaging and drug delivery systems [15,16]. Furthermore, QDs have many superiorities compared to other drug carriers, such as larger specific surface area, smaller size, and stronger adsorption capacity [17].…”

Applications and Immunological Effects of Quantum Dots on Respiratory System

“…showed that Ag–In–Zn–S QDs nanocrystals which were decorated with L−cysteine, 11−mercaptoundecanoic acid (MUA), and lipoic acid modified with folic acid (FA) can be employed as a good approach for engaging doxorubicin (DOX) to FRs in A549. The QD–MUA–FA–DOX complex had a great genotoxicity and cytotoxicity, and also inhibited the migration of A549 significantly ( 22 ).…”