Ethidium bromide eb

Ethidium bromide (EB) was purchased from Solarbio Science & Technology Co. Ltd (Beijing, China); and was formulated into different concentration gradients. Triton X-100 was purchased from Baoxin biotechnological Co. Ltd (Luoyang, China), and was made as a 0.1% stock solution. After 8 h cultured in 1 M medium, D. salina cells were harvested and then re-suspended with the 0.1 M fresh medium. Meanwhile, different concentrations of Triton X-100 (5, 10, 15, 20, 25 and 30 µL) and EB (1.25%, 2.5%, 3.75%, 5%, 6.25% and 7.5%) were immediately added to 1 mL D. salina separately. And then, this mixture was blended briefly using inverting tube. D. salina cells were observed quickly at the point in time of 60 s, 90 s, 120 s, 150 s and 180 s under a fluorescence microscope. In this experiment, four factors were determined orderly which including salt gradient, time, TritonX-100 concentration and EB amount. When one variable of four variables was optimized, the other three parameters were unchanged as described above. The independent experiments were repeated three times at least.

HNTs were provided by Guangzhou Runwo Materials Technology Co., Ltd., China and used without further purification. The elemental composition of used HNTs by X-ray fluorescence (XRF) was determined as follows (wt%): SiO₂, 58.91; Al₂O₃, 40.41; Fe₂O₃, 0.275; P₂O₅, 0.138; TiO₂, 0.071. The weight loss of HNTs was 19.20%, which was mainly occurred in the temperature range of 400–500 °C. Fluorescein isothiocyanate (FITC) (analytical grade) was purchased from Shanghai Yeasen Biotechnology Co., Ltd., Shanghai, China. Indocyanine green (ICG) and streptavidin (SA) were purchased from Sigma-Aldrich (St. Louis, MO, US). Anti-EpCAM aptamer was purchased from Sangon Biotech, Shanghai. Acridine orange (AO) and ethidium bromide (EB) were purchased from Solarbio Science and Technology Co., Ltd., Beijing, China. Ultrapure water was obtained from Milli-Q water system. All the other chemicals were analytically graded and used directly without further purification.