Detection of Placental Extracellular Vesicle Biomarker with Terbium Coordination Polymer

Preeclampsia is a leading cause of maternal and fetal morbidity, with altered placental function being a key contributor to its pathogenesis. Extracellular vesicles (EVs) derived from the placenta have emerged as promising biomarkers for early diagnosis of preeclampsia. However, current EV isolation techniques face challenges related to specificity, yield, and preservation of vesicle integrity. In this proof-of-concept study, we develop a work scheme for the selective isolation of placental EVs and the detection of messenger RNA (mRNA) biomarkers. The coordination polymer is formed using terbium ions and guanosine monophosphate, with the incorporation of monoclonal antibodies targeting placental alkaline phosphatase (PLAP), a marker of trophoblast-derived EVs. Our results show that antibody-functionalized terbium coordination polymer particles efficiently captured PLAP-positive EVs, which could be gently released, preserving their integrity for downstream analysis. Transmission electron microscopy confirms the recovery of intact EVs, while Quantitative Reverse Transcription Polymerase Chain Reaction analysis is performed for the detection of KISS1 mRNA, a potential biomarker for preeclampsia. This method offers a gentle, efficient, and specific approach for EV isolation, providing a valuable tool for studying placental dysfunction and advancing biomarker analysis in preeclampsia.