Key Laboratory of Graphene Technologies and Applications of Zhejiang Province, Ningbo Institute of Materials Technology & Engineering, Chinese Academy of Sciences, Ningbo 315201, P. R. China.
Nanoscale. 2018 Sep 27;10(37):17834-17841. doi: 10.1039/c8nr03435d.
Photoacoustic imaging (PAI) has emerged as a promising clinical technology, thanks to its high-resolution in deep tissues. However, the lack of specificity towards analytes limits further application of the PA probe in molecular imaging. To this end, we herein report a PA and fluorescence (FL) dual-modal probe for the selective detection of ascorbic acid (AA). To realize this design, cobalt oxyhydroxide (CoOOH) was adopted as a multifunctional platform (PA contrast agent, FL quencher and specific oxidant to AA) and hybridized with red-emissive carbon dots (RCDs). In the presence of AA, CoOOH is reduced to Co2+ and meanwhile releases RCDs, resulting in the decrease of PA and recovery of FL signals. We demonstrated the AA detection capabilities of the probe in complicated biological fluids (human serum and urine), living cells, and dual-modal FL/PA imaging in vivo. This work revealed the PAI capacity of CoOOH for the first time, which may inspire researchers to design other CoOOH-based PA probes and further employ RCDs in biology and the clinic.
光声成像是一种有前途的临床技术，这要归功于它在深部组织中的高分辨率。然而，由于对分析物缺乏特异性，限制了 PA 探针在分子成像中的进一步应用。为此，我们在此报告了一种用于选择性检测抗坏血酸 (AA) 的光声 (PA) 和荧光 (FL) 双模态探针。为了实现这一设计，采用了 CoOOH 作为多功能平台 (PA 造影剂、FL 猝灭剂和 AA 的特异性氧化剂) 并与红色发射碳点 (RCD) 杂交。在 AA 的存在下，CoOOH 被还原为 Co2+，同时释放出 RCD，导致 PA 信号降低和 FL 信号恢复。我们在复杂的生物流体 (人血清和尿液)、活细胞中以及体内的双模态 FL/PA 成像中证明了该探针的 AA 检测能力。这项工作首次揭示了 CoOOH 的 PAI 能力，这可能启发研究人员设计其他基于 CoOOH 的 PA 探针，并进一步将 RCD 应用于生物学和临床。
