Chromium(III) Binding Phage Screening for the Selective Adsorption of Cr(III) and Chromium Speciation.
The screening of suitable sorption medium is the key for highly selective solid phase extraction (SPE) of heavy metals. Herein, we demonstrate a universal protocol for producing selective SPE adsorbent through an evolutional approach based on phage display peptide library. By choosing chromium(III) as the model target, immobilized Cr(III) resins are first prepared using Ni-NTA affinity resins for the interaction with NEB heptapeptide phage library. After three rounds of positive biopanning against target Cr(III) and negative biopanning against foreign metal species, Cr(III) binding phages with high selectivity are obtained. The binding affinity and selectivity are further assessed with ELISA. The phages bearing peptide (YKASLIT) is finally chosen and immobilized on cytopore beads for Cr(III) preconcentration. The retained Cr(III) is efficiently recovered by 0.10 mol L(-1) HNO3 and quantified with ICP-MS. By loading 4000 μL of sample solution at pH 7.0 for 2 h and stripping with 400 μL of 0.10 mol L(-1) HNO3, a linear range of 0.05-0.50 μg L(-1) is achieved along with an enrichment factor of 7.1. The limit of detection is derived to be 15 ng L(-1) (3σ, n = 7) with a RSD of 3.6% (0.25 μg L(-1), n = 7). The procedure is validated by analyzing chromium content in a certified reference material GBW08608 (simulate water). In addition, chromium speciation in real water samples is demonstrated. Cr(VI) is first converted into Cr(III), and the latter subjected to the sorption onto the Cr(III) binding phage, followed by elution and quantification of the total chromium amount, and finally speciation is achieved by difference.
Research Center for Analytical Sciences, Northeastern University , Box 332, Shenyang 110819, China.
Ting
T
Yang
Research Center for Analytical Sciences, Northeastern University , Box 332, Shenyang 110819, China.
Xiao-Yu
XY
Zhang
Research Center for Analytical Sciences, Northeastern University , Box 332, Shenyang 110819, China.
Xiao-Xiao
XX
Zhang
Research Center for Analytical Sciences, Northeastern University , Box 332, Shenyang 110819, China.
Ming-Li
ML
Chen
Research Center for Analytical Sciences, Northeastern University , Box 332, Shenyang 110819, China.|Collaborative Innovation Center of Chemical Science and Engineering, Tianjin 300071, China.
Jian-Hua
JH
Wang
D000327:Adsorption; D000595:Amino Acid Sequence; D002857:Chromium / Q000302:isolation & purification*; D006863:Hydrogen-Ion Concentration; D013058:Mass Spectrometry; D008863:Microspheres; D008969:Molecular Sequence Data; D019151:Peptide Library; D010455:Peptides / Q000737:chemistry; D052616:Solid Phase Extraction; D013997:Time Factors; D014874:Water Pollutants, Chemical / Q000302:isolation & purification
D019151:Peptide Library; D010455:Peptides; D014874:Water Pollutants, Chemical; D002857:Chromium
Cr(III); metal binding peptide; phage display peptide library; preconcentration; solid phase extraction