Novel synthetic approach for accessing drug-dye conjugates for targeted tumour therapy

The use of heptamethine cyanine dyes (HMCD) as a vehicle for targeted delivery of drugs to cancer tissues shows promise. The synthesis of drug-dye conjugates is hampered by scalability and purification issues. Herein we disclose synthetic procedure to procure such drug-dye conjugates that avoid the formation of undesired side products. This novel procedure also avoids the use of HPLC, thereby improving the yield and scalability of such drug-dye conjugates. Improving the atom-efficient coupling of drugs to HMCDs, will facilitate the clinical translation of HMCDs as a drug-delivery system for targeted tumour therapies.