toluidine blue + dextran 40

Toluidine blue + dextran 40 (TB-Dex-40) is a lymphatic tracer agent being investigated for sentinel lymph node (SLN) detection and lymphatic mapping, particularly in head and neck cancers. The combination consists of toluidine blue (a metachromatic dye, also known as tolonium chloride) conjugated or combined with dextran-40, a low molecular weight polysaccharide. Dextran-40 acts as a macromolecular carrier that modifies the pharmacokinetic profile of the dye, reducing its diffusion at the injection site and increasing its affinity and retention time within the lymphatic system. Preclinical studies have shown that TB-Dex-40 provides significantly longer staining persistence in sentinel lymph nodes compared to toluidine blue alone, facilitating more accurate surgical identification of drainage pathways. It is designed to improve the specificity of lymphatic vessel staining and prolong the visibility of lymph nodes during surgical procedures.

Other names

toluidine blue-dextran-40tolonium chloride + dextran 40