Mild post-modified metal-organic frameworks applied as solid-phase microextraction coatings for the trace detection of polybrominated biphenyls in human serum

Polybrominated biphenyls (PBBs), as a persistent organic pollutant, have attracted much attention due to their strong toxicity, long half-life, and bioaccumulation. Studies have shown that it can be transmitted through multiple generations. Until now, the presence of PBBs in human serum has been detected in many places worldwide. However, due to the complex of human serum matrix, the methods for the detection of PBBs from serum is complex, time-consuming, and labor-intensive. In order to better promote the understanding of PBBs, it is necessary to establish a method for the detection of trace PBBs in human serum. Therefore, in this paper, the modified metal-organic framework MOF808(Hf)-OPA (octadecylphosphonic acid) was prepared by a simple and mild post-modification method for MOF808(Hf). OPA was successfully modified on the surface of MOF808(Hf), which enhanced the hydrophobicity and stability of MOF without changing the crystallinity, providing a new solution to the current problem of poor stability of MOF. The prepared MOF808(Hf)-OPA was applied in SPME and coupled with GC-MS to develop a new method for the determination of trace PBBs in human serum. The fiber exhibited high enrichment capacity towards PBBs due to its resemblance to PBB in terms of small pore size and hydrophobicity. Moreover, the fiber had a good anti-interference ability under different pH values and matrix, which indicated the feasibility of the method for detecting PBBs in complex substrates. In summary, this study established a simple and green sample pretreatment method for the detection of PBBs in complex matrices. The fiber exhibited excellent stability and anti-interference capabilities, achieving high sensitivity in the detection of PBBs in human serums.