Photodynamic therapy (PDT) is a noninvasive protocol for the treatment of various cancers and nonmalignant diseases. Light, oxygen, and photosensitizer (PS) are the essential three elements in a typical PDT process. Currently, there are two major barriers limiting the further development of PDT. One issue is limited tissue penetration, and the other is the lack of high‐performance PSs. Therefore, the newly emerging two‐photon excited PDT (2PE‐PDT) has attracted considerable attention in recent years due to its advantages such as a higher spatial resolution and a greater penetration depth. In this review, focus is on (i) the principle of 2PE‐PDT, (ii) the progression of PSs for 2PE‐PDT, and (iii) the potential indications and future directions in this field.

中文翻译：

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用于两光子激发光动力疗法的光敏剂

光动力疗法（PDT）是一种用于治疗各种癌症和非恶性疾病的非侵入性治疗方案。在典型的PDT工艺中，光，氧和光敏剂（PS）是必不可少的三个元素。当前，有两个主要的障碍限制了PDT的进一步发展。一个问题是组织渗透受限，另一个问题是缺乏高性能PS。因此，近年来新兴的双光子激发PDT（2PE-PDT）由于具有诸如更高的空间分辨率和更大的穿透深度等优点而备受关注。在本综述中，重点是（i）2PE-PDT的原理，（ii）2PE-PDT的PS的发展，以及（iii）该领域的潜在适应症和未来方向。