Disclosed herein are photosensitizer particle contrast agents suitable for medical imaging and/or photodynamic therapy. The photosensitizer particle contrast agent has a shell and a core encased by the shell. The shell consists essentially of multiple photosensitizer conjugates. Each photosensitizer conjugate consists of a photosensitizer and at least one biodegradable polymer covalently bound to the photosensitizer. According to certain examples, the core has an echogenic contrast-enhancing material loaded therein. In alternative examples, the photosensitizer of at least one of the multiple photosensitizer conjugates has a magnetic contrast-enhancing agent, e.g., a paramagnetic ion, chelated thereto. Also disclosed herein are methods for medical imaging which use imaging compositions containing the photosensitizer particle contrast agents taught in the present disclosure.在此揭示一種光感粒子顯影劑,可應用於顯影和/或光動力療法。所述光感粒子顯影劑具有一殼體和一核體,所述核體被包覆於殼體內。所述殼體主要由複數個光感接合體所組成。每一光感接合體係由一光敏感劑和至少一生物可分解聚合物所組成,所述生物可分解聚合物與光敏感劑共價鍵結。依據具體的實施例,所述核體具有一超音造影增強物質。在可任選的實例中,所述光感接合體有一與之螯合的磁性造影增強劑,如,一順磁離子。再者,本揭示內容更揭示一應用於醫學顯影之方法,此方法包含使用含有本揭示內容之光感粒子顯影劑之組合物。100‧‧‧光感粒子110‧‧‧核體120‧‧‧殼體130、130A、130B‧‧‧光感接合體132A‧‧‧卟啉衍生物132B‧‧‧二氫卟酚衍生物134‧‧‧聚乳酸臂
