Facile synthesis of hydrangea-like copper–tannic acid networks for separation and purification of His-rich proteins with exceptional performance†

Abstract

Highly selective separation and purification of histidine-rich (His-rich) proteins from complex biological samples is crucial for disease diagnosis, but it still remains a challenge. In this work, hydrangea-like Cu–tannic acid (TA) networks were fabricated via one-step assembly of Cu²⁺ and natural polyphenol for separation and purification of bovine hemoglobin (BHb) from complex biosamples. The preparation procedure was simple, fast and cost-effective. Interestingly, hydrangea-like morphology was obtained by the cross-linked assembly of Cu–TA nanosheets and resulted in a hierarchically porous structure. Benefiting from the large surface area and highly abundant Cu²⁺, hydrangea-like Cu–TA networks exhibited exceptional adsorption performance towards BHb including ultra-high adsorption capacity (25 116.6 mg g⁻¹) and excellent selectivity. Moreover, hydrangea-like Cu–TA networks possessed good reusability for five adsorption–desorption cycles without the need for regeneration in fresh reaction solution. In addition, hydrangea-like Cu–TA networks were successfully adopted for highly selective separation and purification of BHb from a complex biosample (bovine whole blood). In a word, this work demonstrated that hydrangea-like Cu–TA networks could act as a cost-effective and sustainable adsorbent with exceptional performance, which showed great potential in separation and purification of His-rich proteins for the omics analysis and disease diagnosis.