膀胱内灌注被认为是检测膀胱癌的有效途径。但是，只有很小一部分的给药剂量渗透到肿瘤组织中，以及保留时间不足限制了它们的应用。在本研究中，开发了一种新型的膀胱内双向灌流样给药模式，以提高膀胱肿瘤成像的诊断准确性。具体而言，超小的AuPd-P-FA纳米探针由于电子结构扰动表现出优异的NIR-II FL成像性能。由于肾代谢和FA靶向特异性的尺寸优势，AuPd-P-FA可以有效地治疗膀胱肿瘤。当AuPd-P-FA在注射后1小时达到最大富集时，激光照射产生的局部微弱热能激活了相变。这种热敏特性可以延长在膀胱中的保留时间，并且在注射后6小时可以清晰地观察到荧光信号，并具有高准确性。这种新型的膀胱内双向灌流样给药模式有望实现早期膀胱癌的无创诊断。版权所有©2023 Elsevier Inc.发表。

Intravesical instillation has been considered an efficient route for detecting bladder cancer. However, only a small fraction of administered dose permeates into tumor tissues, and insufficient retention time limits their application. In this work, a novel intravesical bidirectional perfusion-like administered mode was developed to improve diagnostic accuracy of bladder tumor imaging. Specifically, the ultrasmall AuPd-P-FA Nanoprobe exhibit excellent NIR-II FL imaging performance due to electronic structure perturbation. Benefiting from the size advantage for kidney metabolism and FA targeting specificity, AuPd-P-FA could effectively administration to bladder tumor. When AuPd-P-FA reached maximum enrichment at 1 h post-injection, the localized and mild thermal energy produced upon laser irradiation activated a phase transition. This thermo-sensitive characteristic could prolong the retention time in bladder and the fluorescence signal could be clearly observed at 6 h post-injection with high accuracy. This novel intravesical bidirectional perfusion-like administered mode is expected to achieve a non-invasive diagnosis of early bladder cancer.Copyright © 2023. Published by Elsevier Inc.