Lycopersicon Esculentum (Tomato) Lectin (LEL, TL), Fluorescein, 1 mg. Tomato lectin (from Lycopersicon esculentum) is an effective marker of blood vessels and microglial cells in rodents. Conjugation of the lectin with fluorescein facilitates fast, one-step detection and visualization using intravascular perfusion methods or direct application to tissue sections. The recommended concentration range for use is 5–20 µg/ml. Fluorescein has an excitation maximum of 495 nm and an emission maximum of 515 nm.