Choi Hye Eun, Park Jeong-Min, Jeong Woo Yeup, Lee Su Bin, Kim Jae-Hyuk, Kim Ki Su
School of Chemical Engineering and Institute for Advanced Organic Materials, Pusan National University, Busan 46241, Republic of Korea.
Department of Civil and Environmental Engineering, Pusan National University, Busan 46241, Republic of Korea.
Biomater Res. 2024 Nov 19;28:0106. doi: 10.34133/bmr.0106. eCollection 2024.
Photomedicine, which utilizes light for therapeutic purposes, has several hurdles such as limited tissue penetration for short-wavelength light and inadequate deep tissue efficacy for long-wavelength light. Photon energy upconversion (UC) reveals promise in photomedicine because it enables the conversion of lower-energy photons into higher-energy photon. Lanthanide (Ln)-based inorganic UC system has been extensively studied but faces challenges, including high excitation laser power density, intrinsically subpar UC quantum efficiency, and potential biotoxicity. Recently, an organic-based triplet-triplet annihilation UC (TTA-UC) system has emerged as a novel UC system due to its prolonged emission lifetime upon low power laser excitation and exceptional UC quantum yield. In this study, we developed water-dispersible hyaluronic acid (HA)-conjugated polycaprolactone (PCL) nanoparticles loaded with TTA-UC chromophores (HA-PCL/UC NPs), which allow deeper tissue penetration by converting red light (635 nm) into blue light (470 nm) for noninvasive transdermal delivery. HA-PCL/UC NPs demonstrated a 1.6% high quantum yield in distilled water, improved cellular imaging in HeLa cells, and effectively penetrated the deep tissue of porcine skin, showing upconverted blue light. Our strategy holds significant potential as a next-generation noninvasive photomedicine platform for bioimaging, photo-triggered drug delivery, and photodynamic therapy, ultimately advancing targeted and effective therapeutic interventions.
光医学利用光进行治疗，存在几个障碍，如短波长光的组织穿透有限，长波长光的深部组织疗效不足。光子能量上转换（UC）在光医学中显示出前景，因为它能将低能量光子转换为高能量光子。基于镧系元素（Ln）的无机UC系统已得到广泛研究，但面临挑战，包括高激发激光功率密度、固有的次优UC量子效率和潜在的生物毒性。最近，基于有机的三重态-三重态湮灭UC（TTA-UC）系统因其在低功率激光激发下延长的发射寿命和优异的UC量子产率而成为一种新型UC系统。在本研究中，我们开发了负载TTA-UC发色团的水分散性透明质酸（HA）共轭聚己内酯（PCL）纳米颗粒（HA-PCL/UC NPs），通过将红光（635 nm）转换为蓝光（470 nm）实现无创透皮给药，从而实现更深的组织穿透。HA-PCL/UC NPs在蒸馏水中表现出1.6%的高量子产率，改善了HeLa细胞中的细胞成像，并有效穿透猪皮肤的深部组织，呈现上转换蓝光。我们的策略作为下一代用于生物成像、光触发药物递送和光动力治疗的无创光医学平台具有巨大潜力，最终推动靶向且有效的治疗干预。
