Cyanocobalamin conjugates of cisplatin and diaminocyclohexane-platinum(ii): matrix-assisted laser desorption ionization mass spectrometry characterization using 4-chloro-α-cyanocinnamic acid as the matrix

cis-Diamminedichloroplatinum(ii), also known as cisplatin, is a widely used chemotherapeutic agent to treat several malignant tumours, but unfortunately it causes serious side effects, especially nausea, vomiting and nephrotoxicity.