Novel Respiratory Disease Diagnosis Tool: Development of an Au-ReS₂-Functionalized Extended-gate Field-Effect...

Spirometry is influenced by the patient's subjective condition, which limits the reproducibility of diagnostic results despite being a key diagnostic tool for respiratory diseases. To overcome this, an extended-gate field-effect transistor-type aptasensor for detecting granzyme B (GzmB) and perforin (PRF) is introduced as a proof-of-concept for diagnosing localized immune responses in respiratory diseases. The novel GzmB and PRF aptamers are synthesized using systematic evolution of ligands by exponential enrichment and are subsequently truncated to enhance the target-binding affinity. Au-ReS₂ and the alternating current electrothermal flow technique are applied to amplify the biosensing signal and accelerate detection within 10 min, respectively. Under the 10% human serum, a linear response is observed depending on the target concentration, with the detection limits of 330 fM for GzmB and 440 fM for PRF. The targeted dual-biomarker indicates a strong clinical correlation with bronchial conditions in chronic obstructive pulmonary disease patients. The proposed device demonstrates clear advantages in rapid, selective, and sensitive detection, suggesting its use as a preemptive diagnostic tool for respiratory diseases. This approach is expected to establish promising diagnostic strategies for early detection and therapeutic monitoring of various respiratory diseases, potentially replacing conventional spirometry.