Isolation of hemoglobin with metal–organic frameworks Y(BTC)(H2O)6

The hierarchical metal–organic frameworks (MOFs), such as Y(BTC)(H2O)6, are prepared with yttrium nitrate and benzene-1,3,5-tricarboxylic acid at room temperature. The product is characterized by Fourier transform infrared (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM) and thermogravimetric analysis (TGA). The Y(BTC)(H2O)6 particles are sufficiently rigid for performing solid phase extraction and they exhibit favorable selectivity toward the adsorption of hemoglobin. The adsorption behavior of hemoglobin onto the Y(BTC)(H2O)6 fits the Langmuir adsorption model with a theoretical adsorption capacity of 555.6 mg g−1. An adsorption efficiency of 87.7% for 100 μg mL−1 hemoglobin in 1 mL sample solution (at pH 6.0) is achieved with 0.40 mg Y(BTC)(H2O)6. 77.3% of the retained hemoglobin is readily recovered using a 0.5% (m/v) SDS solution as the stripping reagent. Circular dichroism spectra indicated that the conformation of hemoglobin is maintained during the adsorption–desorption process. The MOFs material is applied for the isolation of hemoglobin from human blood and the purity of the obtained hemoglobin is further verified by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS–PAGE).

The metal–organic frameworks, Y(BTC)(H2O)6, exhibits favorable adsorption toward hemoglobin that is attributed to the coordination interactions between the metal cations and the histidine residues in proteins.Figure optionsDownload as PowerPoint slide