In situ quantification of gold nanoparticles using the total reflection X-ray fluorescence

本申请的目的是购买全反射x射线荧光（TXRF）光谱仪及相关设备，用于细胞培养物和组织中以金纳米颗粒形式的金的原位低水平定量，这是纳米颗粒辅助治疗研究进展的基本要求，也是目前的限制要求。超声微泡与金纳米颗粒联合应用于改善癌组织放射治疗和激光热疗的治疗效果。虽然金纳米颗粒在辅助治疗中的作用的一般物理机制在很大程度上是已知的，但治疗递送的最佳方法以及对金纳米颗粒进入细胞的理解仍然缺失。这就要求我们能够准确地在原位测量输送到癌细胞中的金的含量。在这种情况下，金的定量是一个挑战，因为大多数湿化学方法需要完全破坏样品，并且通常没有足够的检测限，这些检测限足以在用金纳米颗粒处理后检测和定量细胞中预期的极低水平的金。TXRF提供非常低的检测限（ppb水平），并且基于x射线荧光，可以对薄层样品中的金进行完全的原位定量，包括单层和多层细胞培养。TXRF的一个类似但互补的潜在应用领域将是评估人体组织中的其他微量元素，如牙齿或骨骼，或环境，考古和艺术样品。

This proposal is for the purpose of purchasing a total reflection X-ray fluorescence (TXRF) spectrometer, and associated equipment, for the purpose of the in situ low-level quantification of gold, in the form of gold nanoparticle, in cell cultures and tissues, a fundamental, and currently limiting requirement for the advancement of the study of nanoparticle aided therapies. The application of ultrasound-microbubbles in combination with gold nanoparticles is being investigated to improve therapeutic outcome of radiotherapy and laser-mediated thermal therapy of cancerous tissues. Although the general physical mechanism of the action of gold nanoparticles in aiding such therapies is largely known, the optimal method of therapeutic delivery, and an understanding of gold nanoparticle uptake into cells, is still missing. This requires that an accurate in situ measure of gold delivered to cancerous cells be known. Gold quantification is a challenge in such a case as most wet chemical methods require total destruction of the sample, and do not generally present limits of detection which are sufficient to detect and quantify the very low levels of gold expected in cells after treatment with gold nanoparticles. TXRF offers very low limits of detection (at ppb levels), and being based on X-ray fluorescence allows for complete in situ quantification of gold in thin layer samples, including, mono- and multi-layer cell cultures. A similar, but complementary, area of potential application of TXRF would be in the assessment of other trace elements in human tissues, such as in teeth or bone, or in environmental, archeological and art samples in the future.