Fluorescent Neomannosyl Bovine Serum Albumin as Efficient Probe for Mannose Receptor Imaging and MCF-7 Cancer Cell Targeting

Robust carbohydrate conjugated fluorescent bovine serum albumin (BSA) as useful tool to study carbohydrate–receptor interactions and in vivo targeting is reported. Amine terminated α-mannoside was attached to fluorescein labeled BSA via diethyl squarate strategy. The surface functionalization and lectin binding specific to fluorescent neomannosyl glycoprotein were confirmed using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS), surface plasmon resonance (SPR), and microarray imaging. The glycoconjugate was further used to image concanavalin A (ConA), pili of E. coli K12, and lysosomes in MCF-7 cancerous cells successfully, suggesting that this neomannosyl glycoprotein can be used as suitable probe to elucidate carbohydrate–protein interactions, image cancers, and target drug specifically toward tumors.