Desolvation-induced formation of recombinant camel serum albumin-based nanocomposite for glutathione colorimetric determination

Protein-based enzyme mimics hold advantages of easy preparation, desirable compatibility and superior catalytic performance. Taking advantage of the remarkable stability of Bactrian camel serum albumin (CSA) compared with its counterpart in human and bovine, here a novel hemin-loaded nanozyme system was prepared through the desolvation method using a recombinant CSA (rCSA). The obtained hemin-rCSA nanoparticles exhibited improved enzyme mimic activity with higher affinity to the substrates compared with bare hemin and horseradish peroxidase. Moreover, the particle size and morphology of hemin-rCSA NPs was adjustable by the optimization of ethanol addition during the desolvation process. With the efficient encapsulation of hemin in the protein nanocomposite, a colorimetric detection of glutathione with the linear calibration concentration range of 3.2–100 μM with an LOD of 0.667 μM was achieved within 8 min. The available camel-derived serum albumin of recombinant form of improved stability provides a robust and manipulable protein-based nanoplatform for the molecular design of nanozyme system with enormous biomedical potentials. Desolvation-induced formation of hemin-encapsulated recombinant camel serum albumin nanocomposite for the colorimetric detection of glutathione • Recombinant camel serum albumin (rCSA) is prepared to load hemin via the desolvation method. • The produced rCSA-hemin nanoparticles (NPs) exhibit enhanced enzyme-mimicking activity. • rCSA-hemin NPs show improved storage stability. • The size of rCSA-hemin NPs is adjustable. • A rapid colorimetric detection of glutathione using a smartphone was achieved.