Quantum Dots (QDs) are ultra-fine nanometer-sized semiconductor particles with a core-shell structurepossess both electrical and optical properties. Their unique ability to emit pure, monochromatic light on being exposed to light makes them extremely versatile in their applications. The color of the light emitted directly depends on their size and shape. Smaller QDs emit shorter wavelengths, closer to the violet end of the visible light spectrum (~380-450 nm), while larger QDs emit longer wavelengths i.e in reddish spectrum (~620-750 nm). Owing to their “tunability”, QDs can be exploited in a wide range of fluorescent, photonic, and electrochemical applications. QDs represent elements mainly from Group II-VI (e.g., CdSe) or Group III-V (e.g., InP) with the resultant optical and electronic properties of the quantum dots being somewhere between bulk semiconductor material and individual atoms or molecules. Besides applications in energy and photonics, they are under extensive investigation and development for use in disease diagnosis and therapy, specifically in the area of controlled drug delivery, biosensing and imaging. This review surveys the progress of research explores their properties, synthesis, applications, delivery systems in biology, and their toxicity.

中文翻译：

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量子点的合成及其生物医学应用综述

量子点 (QD) 是具有核壳结构的超细纳米级半导体粒子，具有电学和光学特性。它们在暴露于光线下时发出纯净单色光的独特能力使它们在应用中极为通用。直接发出的光的颜色取决于它们的大小和形状。较小的 QD 发射较短的波长，更接近可见光谱的紫色端 (~380-450 nm)，而较大的 QD 发射较长的波长，即在红色光谱 (~620-750 nm) 中。由于它们的“可调性”，QD 可用于广泛的荧光、光子和电化学应用。QD 代表主要来自 II-VI 族（例如 CdSe）或 III-V 族（例如，InP)，量子点的光学和电子特性介于块状半导体材料和单个原子或分子之间。除了在能源和光子学方面的应用外，它们还在广泛的研究和开发中用于疾病诊断和治疗，特别是在受控药物输送、生物传感和成像领域。这篇综述调查了研究进展，探讨了它们的特性、合成、应用、生物学中的传递系统及其毒性。