A molecularly imprinted SPR biosensor for label-free detection of neuron-specific enolase as a cancer biomarker
Microchemical Journal, cilt.227, 2026 (SCI-Expanded, Scopus)
- Yayın Türü: Makale / Tam Makale
- Cilt numarası: 227
- Basım Tarihi: 2026
- Doi Numarası: 10.1016/j.microc.2026.118787
- Dergi Adı: Microchemical Journal
- Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, BIOSIS, Chemical Abstracts Core, Chimica, Index Islamicus, Academic Search Ultimate (EBSCO), Engineering Source (EBSCO)
- Gazi Üniversitesi Adresli: Evet
Özet
Neuron-specific enolase (NSE) is a pivotal clinical biomarker for the diagnosis, staging, and monitoring of neuroendocrine tumors and neurological injuries. Despite its clinical relevance, there remains a critical need for sensitive, cost-effective, and label-free sensing platforms that overcome the limitations of conventional immunoassay-based methods. In this work, a gold nanoparticle (AuNP)-enhanced surface plasmon resonance (SPR) biosensor, based on molecularly imprinted polymer (MIP) technology, was developed for the real-time detection of NSE. The sensing interface was engineered by integrating AuNPs into a poly(2-hydroxyethyl methacrylate-N-methacryloyl-L-histidine methyl ester) [poly(HEMA-MAH)] nanofilm to generate template-specific recognition cavities through metal-coordination and complementary molecular interactions. Surface characterization including water contact angle measurements, atomic force microscopy (AFM), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) confirmed the successful formation of a nanostructured sensing layer with a high surface roughness (Ra = 11.85 ± 2.1 nm). Kinetic and isotherm analyses revealed that the Au-MIP SPR sensor exhibited a broad linear range of 0.15–500 nM and a limit of detection (LOD) of 0.15 nM (equivalent to 7.06 ng/mL). The binding behavior was best described by the Langmuir–Freundlich model (R2 = 0.9945), indicating a heterogeneous distribution of imprinted recognition sites. Selectivity studies against human serum albumin (HSA) and immunoglobulin G (IgG) demonstrated superior NSE recognition on the imprinted surface compared with the non-imprinted polymer (NIP) control, with the calculated imprinting factor validating the template-specific contribution. The sensor maintained excellent reusability over repeated regeneration cycles with a relative standard deviation (RSD) below 1.5%. Preliminary validation in spiked serum and urine matrices demonstrated the feasibility of NSE detection in complex biological environments. Overall, the developed AuNP-integrated MIP-SPR platform provides a stable, antibody-free, and label-free sensing strategy, representing a promising basis for the development of next-generation synthetic receptor-based biomarker monitoring systems.