A phosphate (P i )-selective adsorption system featuring immobilized P i -binding proteins (PBP) has recently attracted attention for ultralow P i removal followed by recovery. This study investigated the adsorption kinetics, affinity, thermodynamics, and selectivity, as well as the effect of pH and temperature on P i adsorption using immobilized PBP (PBP resin). Immobilizing PBP did not affect its P i affinity. Kinetic studies at 22 °C and pH 7.1 showed that the PBP resin achieved 95% of its equilibrium capacity within 0.64 ± 0.2 min. The estimated Langmuir affinity constant (K L ) was 21 ± 5 μM −1 P i (220 ± 52 L/mg-P i ), which is higher than P i adsorbents recently reported in literature. The ideal operating ranges for high-affinity P i adsorption using PBP resin were pH 4.5 to 9 and temperature 14 to 37 °C. The P i -PBP resin adsorption process was not affected by the presence of common anions (Cl − , Br − , NO 2 − , NO 3 − , SO 4 2− , and HCO 3 − ). Adsorption using the P i -PBP resin was exothermic (ΔH = −6.3 ± 1.3 kJ/mol) and spontaneous (ΔG = −39.7 ± 0.1 to −43.2 ± 0.2 kJ/mol) between 14 and 43 °C. These results indicate that PBP resin's P i adsorption rate and affinity surpass those of existing adsorbents. Future work to increase the PBP resin's adsorption capacity is important to its application as a viable P i adsorbent.

The proportion of LTx performed for CF has significantly decreased over time, a trend especially pronounced in pediatric patients. The change in pre-transplant characteristics across eras indicates a trend to perform LTx in more clinically ill and older patients with CF. The overall post-LTx survival has not changed.

There is a strong impetus to establish a circular phosphorus economy by securing internally renewable phosphate (Pi) resources for use as agricultural fertilizers. Reversible Pi adsorption technologies such as ion exchange can remove and recover Pi from water/wastewater for reuse. However, existing reversible adsorbents cannot effectively discriminate against arsenate (As(V)) due to the similarity between As(V) and Pi chemical structure. If As(V) is co‐recovered with Pi, the value of the recovered products for agricultural reuse is low. The objective of this study was to construct an immobilized phosphate‐binding protein (PBP)‐based Pi removal and recovery system and analyze its selectivity for Pi adsorption in the presence of As(V). A range of conditions was tested, including independent, sequential, and simultaneous exposure of the two oxyanions to immobilized PBP (PBP resin). The purity of the recovered Pi product was assessed after inducing controlled desorption of the adsorbed oxyanions at high pH (pH 12.5). Pi constituted more than 97% of the adsorbed oxyanions in the recovered product, even when As(V) was initially present at twofold higher concentrations than Pi. Therefore, PBP resin has potential to selectively remove Pi, as well as release high‐purity Pi free of As(V) contamination suitable for subsequent agricultural reuse. Practitioner points Existing reversible phosphate (Pi) adsorbents cannot effectively discriminate against arsenate (As(V)) due to the similarity in their chemical structure. Co‐recovery of As(V) with Pi can reduce the recovered product's reuse as a fertilizer. An immobilized phosphate‐binding protein (PBP)‐based system can be highly selective for Pi even in the presence of As(V). Pi constituted more than 97% of the recovered product, even when As(V) was present at 2‐fold higher concentrations than Pi. Immobilized PBP offers advantages over existing Pi adsorbents by providing high‐purity Pi products free of As(V) contamination for reuse.

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