In this study we demonstrate for the first time a new approach for highly specific targeting of viable human leukocytes by functionalised gold nanoconjugates made on the basis of citrate-stabilised gold nanoparticles. This immobilisation involves highly specific recognition of the cells of interest by plasma membrane-associated receptor ligands or functional antibodies attached to gold nanoconjugates. Using this technology we managed to deliver pharmacological inhibitors into the target cells. Also we immobilized fully functional human leukocytes utilising both cell lines and rare primary human cells (basophils). This approach demonstrates possibilities of using nanoconjugates for diagnostics, drug delivery and immune therapy.