Two-dimensional singlet oxygen imaging with its near-infrared luminescence during photosensitization

Abstract

Abstract. Photodynamic therapy is a promising cancer treatment that involves activation of photosensitizer by visible light to create singlet oxygen. This highly reactive oxygen species is believed to induce cell death and tissue destruction in PDT. Our approach used a near-infrared area CCD with high quantum efficiency to detect singlet oxygen by its 1270-nm luminescence. Two-dimensional singlet oxygen images with its near-infrared luminescence during photosensitization could be obtained with a CCD integration time of 1 s, without scanning. Thus this system can produce singlet oxygen luminescence images faster and achieve more accurate measurements in comparison to raster-scanning methods. The experimental data show a linear relationship between the singlet oxygen luminescence intensity and sample concentration. This method provides a detection sensitivity of 0.0181 μg/ml (benzoporphyrin derivative monoacid ring A dissolved in ethanol) and a spatial resolution better than 50 μm. A pilot study was conducted on a total of six female Kunming mice. The results from this study demonstrate the system's potential for in vivo measurements. Further experiments were carried out on two tumorbearing nude mice. Singlet oxygen luminescence images were acquired from the tumor-bearing nude mouse with intravenous injection of BPD-MA, and the experimental results showed real-time singlet oxygen signal depletion as a function of the light exposure. C 2011 Society of Photo-Optical Instrumentation Engineers (SPIE).

Photoprotective Effect of the PlantCollaea argentinaagainst Adverse Effects Induced by Photodynamic Therapy

“…With the aim to know if the photoprotective effect was exclusive to ALA-PDT or if it was independent on the PS used, we evaluated the photoprotection of C. argentina against PDT with the other two PSs of clinical use, Verteporfin and Temoporfin which produce singlet oxygen as the main ROS [4,6,7]. Figure 5 shows the effect of C. argentina against PDT under different schemes and extract concentrations.…”

“…ALA and other PSs currently employed in clinical PDT, such as Verteporfin and Temoporfin, produce singlet oxygen during the light exposure and in addition all the PSs are retained in other sites other than the tumor, thus inducing skin photosensitivity [4][5][6][7].…”

Singlet Oxygen Luminescence Image in Blood Vessels During Vascular‐Targeted Photodynamic Therapy

“…For this, Hu et al . developed a 1 O 2 luminescence imaging system with cooled NIR InGaAs camera and two BP filters (16). The 1150 nm long pass (LP) filter and the 1270 nm BP filter were used to block the background signal and to extract 1 O 2 luminescence.…”

Dual-channel imaging system for singlet oxygen and photosensitizer for PDT

“…Recently, Hu et al . reported the images of the 1 O 2 emission with only using a 1.27 μm optical filter with a cooled InGaAs CCD camera with detection limit of ~0.0181 μg/ml BPD-MA in 75% ethanol [ 22 ]. They claimed that a long-pass filter (LP1150) was sufficient to achieve spectral discrimination of the 1 O 2 emission from other possible radiations, such as PS fluorescence, backscattered laser light, and autofluorescence from tissues in vivo .…”