Photodynamic therapy (PDT) has been clinically applied to cure various diseases including cancer. Indeed, photophrin (porfimer sodium, Axcan Pharma, Montreal, Canada), a heterogenous mixture of porphyrins, was the first photosensitizer (PS) approved for the treatment of human bladder cancer in 1993 in Canada. Over the past 10 years the use of PDT in the treatment of benign and malignant lesions has increased dramatically. However, PDT is still considered as an adjuvant strategy due to its limitations, primarily including low tissue penetration by light and inaccurate lesion selectivity by the PSs. To overcome this scenario, new technologies and approaches including nanotechnology have been incorporated into the concept of PS formulations as PS delivery systems, as PSs per se or as energy transducers. The ideal nanophotosensitizer (NPS) for cancer therapy should possess the following characteristics: biocompatibility and biodegradability without toxicity, stability in physiological conditions, tumor specific targeting, strong near infrared absorption for efficient and sufficient light absorbance and large singlet oxygen quantum yield for PDT. To fulfill these requirements, several nanoscale delivery platforms and materials have been developed. In this review we will focus on the state of the art of nanotechnology contributions to the optimization of PDT as a therapeutic alternative to fight against cancer. For this purpose we will start from the basic concepts of PDT, discuss the versatility in terms of NPS formulations and how to tackle the deficiencies of the current therapy. We also give our critical view and suggest recommendations for improving future research on this area.

光动力疗法（PDT）已在临床上应用于治疗包括癌症在内的各种疾病。事实上，卟啉的异质混合物 photophrin（porfimer sodium，Axcan Pharma，Montreal，Canada）是 1993 年在加拿大批准用于治疗人类膀胱癌的第一种光敏剂 (PS)。在过去的 10 年中，PDT 在治疗良恶性病变中的应用急剧增加。然而，由于其局限性，PDT 仍被认为是一种辅助策略，主要包括光对组织的低穿透性和 PS 对病变选择性不准确。为了克服这种情况，包括纳米技术在内的新技术和方法已被纳入 PS 制剂的概念中，作为 PS 递送系统、PS 本身或作为能量转换器。用于癌症治疗的理想纳米光敏剂（NPS）应具备以下特性：生物相容性和生物降解性，无毒性，生理条件下的稳定性，肿瘤特异性靶向，强近红外吸收，有效和充分的光吸收，以及大的单线态氧量子产率用于 PDT。为了满足这些要求，已经开发了几种纳米级交付平台和材料。在这篇综述中，我们将重点关注纳米技术对优化 PDT 作为抗癌治疗替代方案的最新贡献。为此，我们将从 PDT 的基本概念开始，讨论 NPS 制剂的多功能性以及如何解决当前疗法的不足。