The difference between isothioblue and methylene blue

1 and isothioblue (molecular weight 543.6KD) are 1 blue dye tracers approved by the US Food and Drug Administration. Isothiocyanate has large molecular weight and weak binding force with protein. After injection, it quickly enters lymphatic vessels and rarely spreads to surrounding tissues and blood. Its advantages are deep dyeing and low incidence of adverse reactions. The disadvantage is that it takes a short time to maintain the blue staining state of lymph nodes, which is expensive and difficult to buy in China.

2. Methylene blue (molecular weight 373.9KD) is a widely used blue dye tracer in China. Due to its small molecular weight, methylene blue soon spread to the surrounding tissues after injection, some of which entered the blood, and only a small amount entered the lymphatic vessels and concentrated in SLN. The advantages of methylene blue are low price, intuitive operation and easy popularization. The disadvantage is that the dyeing is shallow and the incidence of adverse reactions is high. Methylene blue, isothioblue and patent blue have similar success rates and false negative rates. Methylene blue is an effective and reliable substitute when there is no imported blue dye in the domestic market.