Fluorescence imaging has become an essential tool in biomedical research.However,non-invasive deep-tissue threedimensional optical in vivo imaging with the high spatiotemporal resolution is challenging due to the inte...Fluorescence imaging has become an essential tool in biomedical research.However,non-invasive deep-tissue threedimensional optical in vivo imaging with the high spatiotemporal resolution is challenging due to the interaction between photons and tissues.Beam shaping has been used to tailor microscopy techniques to enhance microscope performance.The nearinfrared window(NIR)between 700 and 1,700 nm,generally emphasized as the NIR-II(1,000–1,700 nm)window,has been developed into a promising bio-optical solution chosen as the lower interaction effect in this spectrum,showing potential in basic biological research and clinical application.In this review,we summarize the existing methods to increase penetration depth and extensively describe biological microscopy techniques,NIR-II spectral windows,and fluorophores.Strategies to improve bioimaging performance and NIR-II imaging applications are introduced.Based on the current research achievements,we elucidate the main challenges and provide some recommendations and prospects for deep tissue penetration fluorescence for future biomedical applications.展开更多
Experimental techniques for measurement of optical penetration depth and refractive index of human tissue are presented, respectively. Optical penetration depth can be obtained from the measurement of the relative flu...Experimental techniques for measurement of optical penetration depth and refractive index of human tissue are presented, respectively. Optical penetration depth can be obtained from the measurement of the relative fluencc-depth distribution inside the target tissue. The depth of normal and carcinomatous human lung tissues irradiated with the wavelengths of 406.7, 632.8 and 674.4 nm in vitro are respectively determined. In addition, a novel simple method based on total internal reflection for measuring the refractive index of biotissue in vivo is developed, and the refractive indices of skin from people of different age, sex and skin color are measured. Their refractive indices are almost same and the average is 1.533.展开更多
Photothermal therapy(PTT)triggered by second near-infrared(NIR-II)light(1000–1400 nm)has shown great potential in tumor ablation because of its good tissue penetrability.However,NIR-II PTT still cannot treat tumors u...Photothermal therapy(PTT)triggered by second near-infrared(NIR-II)light(1000–1400 nm)has shown great potential in tumor ablation because of its good tissue penetrability.However,NIR-II PTT still cannot treat tumors underneath skin because of the light scattering effect of skin components.This research aims to promote the NIR-II penetrability of skin tissue by weakening the light scattering effect from the refractive index inhomogeneity among skin constituents.展开更多
Photodynamic therapy(PDT)has been applied in clinical treatment of tumors for a long time.However,insufficient supply of pivotal factors including photosensitizer(PS),light,and oxygen in tumor tissue dramatically redu...Photodynamic therapy(PDT)has been applied in clinical treatment of tumors for a long time.However,insufficient supply of pivotal factors including photosensitizer(PS),light,and oxygen in tumor tissue dramatically reduces the therapeutic efficacy of PDT.Nanoparticles have received an influx of attention as drug carriers,and recent studies have demonstrated their promising potential to overcome the obstacles of PDT in tumor tissue.Physicochemical optimization for passive targeting,ligand modification for active targeting,and stimuli-responsive release achieved efficient delivery of PS to tumor tissue.Various trials using upconversion NPs,two-photon lasers,X-rays,and bioluminescence have provided clues for efficient methods of light delivery to deep tissue.Attempts have been made to overcome unfavorable tumor microenvironments via artificial oxygen generation,Fenton reaction,and combination with other chemical drugs.In this review,we introduce these creative approaches to addressing the hurdles facing PDT in tumors.In particular,the studies that have been validated in animal experiments are preferred in this review over proof-of-concept studies that were only performed in cells.展开更多
基金This work was financially supported by the China Postdoctoral Science Foundation(No.2019M661026)the National Key Research and Development Program of China(No.2021YFF1200700)+3 种基金the National Natural Science Foundation of China(Nos.91859101,81971744,U1932107,814717866,and 11804248)the Natural Science Foundation of Tianjin(Nos.20JCQNJC01270 and 21JCBJC00460)the Public Health Science and Technology Major Project of Tianjin(No.21ZXGWSY00070)the Independent Innovation Foundation Tianjin University(No.2021XT-0018).
文摘Fluorescence imaging has become an essential tool in biomedical research.However,non-invasive deep-tissue threedimensional optical in vivo imaging with the high spatiotemporal resolution is challenging due to the interaction between photons and tissues.Beam shaping has been used to tailor microscopy techniques to enhance microscope performance.The nearinfrared window(NIR)between 700 and 1,700 nm,generally emphasized as the NIR-II(1,000–1,700 nm)window,has been developed into a promising bio-optical solution chosen as the lower interaction effect in this spectrum,showing potential in basic biological research and clinical application.In this review,we summarize the existing methods to increase penetration depth and extensively describe biological microscopy techniques,NIR-II spectral windows,and fluorophores.Strategies to improve bioimaging performance and NIR-II imaging applications are introduced.Based on the current research achievements,we elucidate the main challenges and provide some recommendations and prospects for deep tissue penetration fluorescence for future biomedical applications.
基金This work was supported by the National Natural Science Foundation of China under Grant No.60178022the Fujian Provincial Natural Science Foundation under Grant No.2002F008.
文摘Experimental techniques for measurement of optical penetration depth and refractive index of human tissue are presented, respectively. Optical penetration depth can be obtained from the measurement of the relative fluencc-depth distribution inside the target tissue. The depth of normal and carcinomatous human lung tissues irradiated with the wavelengths of 406.7, 632.8 and 674.4 nm in vitro are respectively determined. In addition, a novel simple method based on total internal reflection for measuring the refractive index of biotissue in vivo is developed, and the refractive indices of skin from people of different age, sex and skin color are measured. Their refractive indices are almost same and the average is 1.533.
基金from the National Natural Science Foundation of China(grant no.21825503).
文摘Photothermal therapy(PTT)triggered by second near-infrared(NIR-II)light(1000–1400 nm)has shown great potential in tumor ablation because of its good tissue penetrability.However,NIR-II PTT still cannot treat tumors underneath skin because of the light scattering effect of skin components.This research aims to promote the NIR-II penetrability of skin tissue by weakening the light scattering effect from the refractive index inhomogeneity among skin constituents.
基金supported by Basic Research Program(2016R1C1B3013951,2021R1F1A1061286,and 2021R1A4A3031875)through the National Research Foundation of Korea(NRF)funded by the Korean government(Ministry of Science,ICT,and Future Planning).
文摘Photodynamic therapy(PDT)has been applied in clinical treatment of tumors for a long time.However,insufficient supply of pivotal factors including photosensitizer(PS),light,and oxygen in tumor tissue dramatically reduces the therapeutic efficacy of PDT.Nanoparticles have received an influx of attention as drug carriers,and recent studies have demonstrated their promising potential to overcome the obstacles of PDT in tumor tissue.Physicochemical optimization for passive targeting,ligand modification for active targeting,and stimuli-responsive release achieved efficient delivery of PS to tumor tissue.Various trials using upconversion NPs,two-photon lasers,X-rays,and bioluminescence have provided clues for efficient methods of light delivery to deep tissue.Attempts have been made to overcome unfavorable tumor microenvironments via artificial oxygen generation,Fenton reaction,and combination with other chemical drugs.In this review,we introduce these creative approaches to addressing the hurdles facing PDT in tumors.In particular,the studies that have been validated in animal experiments are preferred in this review over proof-of-concept studies that were only performed in cells.