(2,4,5- triphenylimidazole; Fig. 6) Nitrogenous organic base that exhibits lemon yellow chemiluminescence when it reacts with oxygen in presence of a strong base (such as NaOH). Is one of the few long-lasting chemiluminescent molecules. It forms dimers that have photochromic properties can reversibly change colour in presence of electromagnetic radiation such as light). Lophine is also used as an analytical reagent for trace metal ion detection and in biomedical science, since some of its derivatives can detect organic substances in biological materials.