This work describes the basic principles of Total-reflection X-Ray Fluorescence (TXRF) spectrometry and some of its most outstanding applications for investigating metal traces, mainly in biological and biomedical samples. TXRF is an analytical technique that combines the versatility of elemental analysis by X-ray energy dispersion with a low detection limit in the order of picograms of absolute mass or a few ppb (μg L⁻¹) as concentration. The microanalytical capacity of TXRF allows the study of small sample quantities. The TXRF can perform qualitative and mass ratio analyses of the elements present in a sample of only a few hundred nanograms. These properties are of great importance in the research of metal traces in biological systems, as they allow fast, precise, and accurate characterisation of the elemental fingerprint at trace level. Its successful application in studies of the coordination kinetics of new platinum-based antitumor drugs with DNA, its application in the study profile of the metal in healthy and cancerous human tissues, or even its application in the study of the processes of metal diffusion through cell membranes are just a few examples of TXRF capabilities in the biomedical sciences. This brief review's main objective is to provide an overview of the physical principles and possibilities of TXRF spectrometry. It also highlights some of the most outstanding applications that have been developed so far, mainly in the biological field, so that the reader can evaluate their potential applications.

中文翻译：

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生物分析科学中的 TXRF 光谱法：简要回顾

这项工作描述了全反射 X 射线荧光 (TXRF) 光谱法的基本原理及其在研究金属痕量（主要是在生物和生物医学样品中）中的一些最杰出的应用。TXRF 是一种分析技术，它结合了通过 X 射线能量分散进行元素分析的多功能性和绝对质量皮克级或几 ppb (μg L ^-1) 作为浓度。TXRF 的微量分析能力允许研究小样本量。TXRF 可以对仅几百纳克的样品中存在的元素进行定性和质量比分析。这些特性在生物系统中金属痕量的研究中非常重要，因为它们可以在痕量水平上快速、精确和准确地表征元素指纹。其成功应用于研究新型铂类抗肿瘤药物与 DNA 的配位动力学，应用于研究金属在健康和癌性人体组织中的分布，甚至应用于研究金属通过细胞的扩散过程膜只是生物医学科学中 TXRF 能力的几个例子。这个简短的回顾' 主要目的是概述 TXRF 光谱法的物理原理和可能性。它还重点介绍了迄今为止开发的一些最杰出的应用，主要是在生物领域，以便读者评估它们的潜在应用。