Low-picomolar, label-free procalcitonin analytical detection with an electrolyte-gated organic field-effect transistor based electronic immunosensor

Preethi Seshadri, Kyriaki Manoli, Nicole Schneiderhan-Marra, Uwe Anthes, Piotr Wierzchowiec, Klaus Bonrad, Cinzia Di Franco, Luisa Torsi

Research output: Contribution to journalArticleScientificpeer-review

97 Citations (Scopus)
93 Downloads (Pure)


Herein a label-free immunosensor based on electrolyte-gated organic field-effect transistor (EGOFET) was developed for the detection of procalcitonin (PCT), a sepsis marker. Antibodies specific to PCT were immobilized on the poly-3-hexylthiophene (P3HT) organic semiconductor surface through direct physical adsorption followed by a post-treatment with bovine serum albumin (BSA) which served as the blocking agent to prevent non-specific adsorption. Antibodies together with BSA (forming the whole biorecognition layer) served to selectively capture the procalcitonin target analyte. The entire immunosensor fabrication process was fast, requiring overall 45 min to be completed before analyte sensing. The EGOFET immunosensor showed excellent electrical properties, comparable to those of bare P3HT based EGOFET confirming reliable biosensing with bio-functional EGOFET immunosensor. The detection limit of the immunosensor was as low as 2.2 pM and within a range of clinical relevance. The relative standard deviation of the individual calibration data points, measured on immunosensors fabricated on different chips (reproducibility error) was below 7%. The developed immunosensor showed high selectivity to the PCT analyte which was evident through control experiments. This report of PCT detection is first of its kind among the electronic sensors based on EGOFETs. The developed sensor is versatile and compatible with low-cost fabrication techniques.

Original languageUndefined/Unknown
Pages (from-to)113–119
JournalBiosensors and Bioelectronics
Issue number104
Publication statusPublished - 2018
MoE publication typeA1 Journal article-refereed


  • Immunosensor
  • Procalcitonin
  • Label-free detection
  • Electrolyte-gated organic field-effect transistors

Cite this