Using CdTe/ZnSe core/shell quantum dots to detect DNA and damage to DNA

Abstract

CdTe/ZnSe core/shell quantum dot (QD), one of the strongest and most highly luminescent nanoparticles, was directly synthesized in an aqueous medium to study its individual interactions with important nucleobases (adenine, guanine, cytosine, and thymine) in detail. The results obtained from the optical analyses indicated that the interactions of the QDs with different nucleobases were different, which reflected in different fluorescent emission maxima and intensities. The difference in the interaction was found due to the different chemical behavior and different sizes of the formed nanoconjugates. An electrochemical study also confirmed that the purines and pyrimidines show different interactions with the core/shell QDs. Based on these phenomena, a novel QD-based method is developed to detect the presence of the DNA, damage to DNA, and mutation. The QDs were successfully applied very easily to detect any change in the sequence (mutation) of DNA. The QDs also showed their ability to detect DNAs directly from the extracts of human cancer (PC3) and normal (PNT1A) cells (detection limit of 500 pM of DNA), which indicates the possibilities to use this easy assay technique to confirm the presence of living organisms in extreme environments.

Detection of ROS Generated by UV‐C Irradiation of CdS Quantum Dots and their Effect on Damage to Chromosomal and Plasmid DNA

“…A concentration-dependent genotoxicity of mercaptoacetic acid-coated CdSe QDs towards plasmid DNA observed even in the dark was discussed in terms of the cadmium-mercaptoacetic acid complex formation in the solution of QDs and an interaction of this complex with DNA through the groove-binding mode [42]. Various interactions of the CdTe/ZnSe core/shell QDs with purines and pyrimidines have been shown recently and used in a novel QD-based method for the detection of presence of the DNA, damage to DNA, and mutation [43]. Damage to ct DNA caused by CdSe QDs using nucleic acid molecular "light switches" was reported as to be not due to photo-induced liberation of Cd 2 + , but due to the production of free radicals and ROS [44].…”

Selenium Species: Current Status and Potentials in Cancer Prevention and Therapy

“…Aside from direct therapeutic effects, chemically modified SeNPs can function as vehicles that endow the carried objects with favorable properties like tumor targeting [150,157], high efficacy [137,144], and low toxicity [139]. Notably, chemosynthetic SeNPs were also examined as diagnostic agents [145,147,149], imaging agents [146,153], and radiosensitizers [130,158]. Overall, chemosynthesis is the most common method used to obtain and modify SeNPs, because the process is easy to implement and control.…”

“…So far, results from laboratories regarding the anticancer property of SeNPs have mainly been positive. SeNPs showed anticancer effects in a range of cancers, including hepatocarcinoma [128,140], breast cancer [122,129,141], colon adenocarcinoma [124,132], lymphoma [133], esophageal cancer [143], prostate cancer [136,147], ovarian cancer [137], and glioma [148]. Further studies and clinical trials are needed to elucidate the possible applications of SeNPs in oncology.…”

Review: immunoassays in DNA damage and instability detection

“…DNA damage and quantification of nucleic acids may be achieved through graphene quantum dots binding to damaged ssDNA pre-labeled with gold nanoparticles [34]. Recently, CdTe/ZnSe QDs have been proved to interact with nucleobases (which show different fluorescent emission for every base), allowing to apply this method to detect DNA damage and mutations at the level of 500 pM of DNA [84]. A different study shows the possibility of detection of DNA damage caused by UV radiation and hydroxyl radicals through binding carbon dots (C-dots) to the genomic DNA extracted from PC3 cells [85].…”