Solubilization of Hexyl Aminolevulinate by Surfactants for Tumor Fluorescence Detection

Abstract

Hexyl aminolevulinate (HAL) is a lipophilic derivative of 5‐aminolevulinic acid (5‐ALA) and can induce more protoporphyrin IX (PpIX) formation and stronger fluorescence intensity (FI) than 5‐ALA, which will greatly facilitate photodynamic diagnosis and therapy. The main drawback of HAL is its low solubility in neutral aqueous media. In this study, surfactants were used to increase HAL solubility in the cell culture medium and serum, followed by in vitro fluorescence formation measurement in human pancreatic cancer cells (SW1990) and in vivo fluorescence detection in tumor‐bearing mice. The results showed that Tween 80 (TW80) and Kolliphor® HS 15 (HS15) increased the solubility of HAL in the selected media. Although TW80 and HS15 exhibited in vitro cytotoxicity at high concentrations (5 mg mL−1), they facilitated fluorescent signal formation at the early stage of cell incubation. When surfactants were used, the FI should be determined without the routine washing process because surfactant‐containing culture medium caused the loss of synthesized PpIX during the washing process. When HAL dissolved in TW80 solution was injected intraperitoneally into pancreatic cancer‐bearing mice at a dose of 50 mg kg−1, the tumors exhibited red fluorescence, which indicated that systemic administration of surfactant‐solubilized HAL might be applicable for tumor fluorescence detection in vivo.

Photocatalytic Activity of ZnO–SnO2 Ceramic Nanofibers for RhB Dye Degradation: Experimental Design, Modeling, and Process Optimization

“…A lot of these pollutants, beside their visual unaesthetic appearance, have a high level of toxicity . Rhodamine B (RhB) is an important dye of xanthene group used in many industrial processes, such as paper and textile dyeing and the production of dye lasers . There are several known treatment methods of effluents and among them: adsorption, coagulation, ion flotation, and sedimentation have been reported.…”