Preparation of a Sandwich-like Complex "MIPs-Target Molecule-Magnetic SERS Probe" and SERS Determination of Immunoglobulin G

Application of microfluidic technology based on surface-enhanced Raman scattering in cancer biomarker detection: A review

With the continuous discovery and research of predictive cancer-related biomarkers, liquid biopsy shows great potential in cancer diagnosis. Surface-enhanced Raman scattering (SERS) and microfluidic technology have received much attention among the various cancer biomarker detection methods. The former has ultrahigh detection sensitivity and can provide a unique fingerprint. In contrast, the latter has the characteristics of miniaturization and integration, which can realize accurate control of the detection samples and high-throughput detection through design. Both have the potential for point-of-care testing (POCT), and their combination (lab-on-a-chip SERS (LoC-SERS)) shows good compatibility. In this paper, the basic situation of circulating proteins, circulating tumor cells, exosomes, circulating tumor DNA (ctDNA), and microRNA (miRNA) in the diagnosis of various cancers is reviewed, and the detection research of these biomarkers by the LoC-SERS platform in recent years is described in detail. At the same time, the challenges and future development of the platform are discussed at the end of the review. Summarizing the current technology is expected to provide a reference for scholars engaged in related work and interested in this field.

Imprinted biopolymers as green abiotic route in immunoglobulin affinity plasmonic sensing

The relentless research in material science is pushing towards sustainable building blocks, which may be exploited in the molecularly imprinting technology, a potentially ground-breaking tool for producing affinity mimetic receptors. In this scenario, we report and characterize a novel polynorepinephrine (PNE)-based mimetic for IgG detection, biomolecules of utmost clinical interest, coupled to a label-free and real-time sensing based on Surface Plasmon Resonance (SPR). A "molecular walk" around the Y-shaped IgG structure is performed to select small peptide portions to be used as templates during the epitope imprinting process. For real-time diagnosis, the mimetic receptor is integrated into SPR sensing platform, to directly target the IgG both in standard solutions and human serum specimens using the standard addition method. The designed platform is characterized in terms of binding kinetic/affinity parameters and analytical figures of merit, (selectivity, repeatability, limit of detection and quantification, namely 0.90 ± 0.02 μg mL^-1 and 3.01 ± 0.07 μg mL^-1, respectively), displaying excellent promising outcomes also when the material is subjected to thermal stress. Comprehensively, the excellent analytical performances of the MIP-based SPR sensing and the well-known versatility of such biopolymer encourage the further development of serological point-of-care testing for IgG antibodies detection.

Application progress of magnetic molecularly imprinted polymers chemical sensors in the detection of biomarkers

Specific recognition and highly sensitive detection of biomarkers play an essential role in identification, early diagnosis and prevention of many diseases. Magnetic molecularly imprinted polymers (MMIPs) have been widely used to capture biomimetic receptors for targets in various complex matrices due to their superior recognition ability, structural stability, and rapid separation characteristics, which overcome the existing deficiencies of traditional recognition elements such as antibodies, aptamers. The integration of MMIPs as recognition elements with chemical sensors opens new opportunities for the development of advanced analytical devices with improved selectivity and sensitivity, shorter analysis time, and lower cost. Recently, MMIPs-chemical sensors (MMIPs-CS) have made significant progress in detection, but many challenges and development spaces remain. Therefore, this review focuses on the research progress of the sensor based on biomarker detection and introduces the surface modification of the magnetic support material used to prepare high selective MMIPs, as well as the selective extraction of target biomarkers by MMIPs from the complex biological sample matrix. Based on the understanding of optical sensors and electrochemical sensors, the applications of MMIPs-optical sensors (MMIPs-OS) and MMIPs-electrochemical sensors (MMIPs-ECS) for biomarker detection were reviewed and discussed in detail. Moreover, it provides an overview of the challenges in this research area and the potential strategies for the rational design of high-performance MMIPs-CS, accelerating the development of multifunctional MMIPs-CS.