Carbon dots (CDs) have become a potential material for biosensing, drug delivery, and bioimaging because of their strong fluorescence, for which they are referred to as fluorescent carbon dots. CDs have drawn significant attention as a new class of carbonaceous nanomaterials with accelerating applications in varying different technologies. This attention is mainly based on a multitude of appealing properties of CDs, such as high hydrophilicity, biodegradability, biocompatibility, chemical stability, and ease of surface modification, together with their unique optic properties. In this review, CDs were classified and evaluated based on the difference in precursors and preparation methods. The synthetic methods of CDs were summarized, and their luminescence mechanism was analyzed. The applications of CDs in biosensing, drug delivery, energy, and bioimaging were also discussed. The issues and challenges of CDs were analyzed for their further development, with specific emphasis on the toxicity profiles or lack thereof, especially that of cytotoxicity and long-term genotoxicity developed secondary to nanotoxic effects, of carbon dot-based systems. Additional research in toxicity is sure to lead to improved baseline nanosafety statistics for CDs and will be a crucial determinant in the adoption of CDs into many fields across all scientific disciplines, as well as indirectly assist in the development of more efficient and cost-effective technologies. Suggestions for the development of the concepts contemplated herein were also provided, along with additional insight into the controversy concerning the phenomenon of emission and the upconverted photoluminescence.

中文翻译：

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荧光碳点是新的量子点：它们在新兴技术和纳米安全方面的潜力概述

碳点（CDs）由于具有很强的荧光，已成为生物传感、药物输送和生物成像的潜在材料，因此被称为荧光碳点。CDs 作为一种新型碳纳米材料，在不同的技术中加速应用，引起了人们的极大关注。这种关注主要基于 CD 的众多吸引人的特性，例如高亲水性、生物降解性、生物相容性、化学稳定性和易于表面改性，以及它们独特的光学特性。在这篇综述中，根据前体和制备方法的差异对 CD 进行了分类和评估。综述了CDs的合成方法，分析了其发光机理。CDs在生物传感、药物输送、能源、还讨论了生物成像。分析了 CD 的问题和挑战，以进一步发展，特别强调毒性特征或缺乏毒性特征，尤其是细胞毒性和长期遗传毒性，这些毒性是继发于纳米毒性效应的碳点系统。额外的毒性研究肯定会改善 CD 的基线纳米安全统计数据，并将成为将 CD 应用于所有科学学科的许多领域的关键决定因素，并间接协助开发更高效和更具成本效益的技术. 还提供了对此处设想的概念的发展的建议，以及对有关发射现象和上转换光致发光的争议的额外见解。分析了 CD 的问题和挑战，以进一步发展，特别强调毒性特征或缺乏毒性特征，尤其是细胞毒性和长期遗传毒性，这些毒性是继发于纳米毒性效应的碳点系统。对毒性的额外研究肯定会改善 CD 的基线纳米安全统计数据，并将成为将 CD 应用于所有科学学科的许多领域的关键决定因素，并间接协助开发更有效和更具成本效益的技术. 还提供了对此处设想的概念的发展的建议，以及对有关发射现象和上转换光致发光的争议的额外见解。分析了 CD 的问题和挑战，以进一步发展，特别强调毒性特征或缺乏毒性特征，尤其是细胞毒性和长期遗传毒性，这些毒性是继发于纳米毒性效应的碳点系统。额外的毒性研究肯定会改善 CD 的基线纳米安全统计数据，并将成为将 CD 应用于所有科学学科的许多领域的关键决定因素，并间接协助开发更高效和更具成本效益的技术. 还提供了对此处设想的概念的发展的建议，以及对有关发射现象和上转换光致发光的争议的额外见解。