Influence of Quantum Dot Surface on Electrochemical DNA Sensing Mechanism

Abstract

Owing to their high surface‐to‐volume ratio, electrocatalytic activity, biocompatibility and novel electron transport properties, quantum dots (QDs) are highly attractive materials for the ultrasensitive detection of biological macromolecules via bioelectronic devices. In this study, a QD‐based genosensor was developed, in which Ga2Te3‐based QDs were synthesized using an aqueous solution approach by mixing 3‐mercaptosuccinic acid (3MSA)‐capped gallium metal precursor with reduced tellurium metal. The results enabled us to reach an original understanding related to the active material involved in the probe DNA sensing mechanism. The morphological and structural characterization of the QDs was performed prior to their utilization in a DNA sensor construction. High‐resolution TEM (HR‐TEM) and atomic force microscopy (AFM) images confirmed the spherical and crystalline nature of the QDs, whereas X‐ray photoelectron spectroscopy (XPS) and X‐ray diffraction (XRD) analyses were able to confirm the oxidation states and formation of the prepared QDs. UV/Vis was capable of finding the optical band gap energy and the photostability of the QDs. The resultant Ga2Te3 QDs together with metal ions confirmed their use for DNA signal detection through their DNA binding mechanism in the genosensor construction. Genosensing in Cs+ and Li+ ions exhibited high sensitivity (2.74–3.69 μA ng−1 mL) and very low detection limits (0.4 pg mL−1) with a linear dynamic range of 0.1–1 ng mL−1.

Decoding the Atomic Structure of Ga2Te5 Pulsed Laser Deposition Films for Memory Applications Using Diffraction and First-Principles Simulations

“…In other words, a controlled crystallization of the amorphous Ga2Te5 PLD film yields a high-quality, stable tetragonal crystal promising for photovoltaic, thermoelectric, en- Even more surprisingly, gallium pentatelluride appears to be perfectly stable after 15 months at room temperature, Figure S1 (Supplementary Information), in contrast to bulk Ga 2 Te 5 , transforming into cubic Ga 2 Te 3 and trigonal tellurium within several weeks [30]. In other words, a controlled crystallization of the amorphous Ga 2 Te 5 PLD film yields a highquality, stable tetragonal crystal promising for photovoltaic, thermoelectric, energy storage, and memory applications [33][34][35][36][37]. On the contrary, the slow cooling or fast quenching of molten Ga 2 Te 5 gives a polycrystalline mixture of cubic gallium sesquitelluride and trigonal Te, Figure S1, fully consistent with the Ga-Te phase diagram, Figure 1d.…”

“…Consequently, the relationship between the amorphous material—obtained by the near instantaneous freezing of the highly excited fragments, particles, liquid globules, etc., existing in the laser-induced plasma (plume)—and a metastable crystal is expected to be complex, leaving room for various intermediate configurations and states. Deep insights into the atomic structure and associated electronic, optical, thermal, and other properties are a key for the rational design of next-generation PCMs and new functional materials for use in photovoltaic, thermoelectric, DNA sensing, and energy storage applications [ 33 , 34 , 35 , 36 , 37 ].…”

Ultrasensitive Label-Free DNA Detection Based on Solution-Gated Graphene Transistors Functionalized with Carbon Quantum Dots

“…Carbon quantum dots (CQDs) are a good biorecognition linker because their surfaces have rich functional groups. − Many types of CQDs have been designed in many applications of biosensors to enhance their performances. ,, However, the CQDs of fluorescence technology for DNA detection suffer from a low detection limit of nanomolar level (17.4 nM) . Recently, our group presented a new CQD-functionalized SGGT for Fe 3+ ion detection and Cu 2+ ion detection.…”

SARS‐CoV‐2 N Gene‐Targeted Anodic Stripping Voltammetry Sensor Using a Novel CoS‐NGQD/Pt@Pd Platform and Au‐DNA‐CdTe QD Probe

“…[11,40,41] Quantum dots (QDs) are one of promising because of their inherent electrochemical activity, tunable catalytic activity, and large surface area, which can ease the adsorption of biomolecules and the adjustable surface chemistry to attach recognition probes at the surface of QDs, which enables improved electrochemical sensing applications and bioimaging without the use of expensive fluoroprobes . [42,43] QD-attached capturing probes have gained substantial attention in electrochemical sensing applications because the synergistic effect between the probe and QD can amplify the electrochemical response significantly and it has been utilized mainly for the detection of pathogenic DNA and RNA. [44][45][46] Among the carbonbased nanomaterials, graphene QDs (GQD) are mostly used in electrochemical sensor platforms.…”