SPR Platform

YanGeneBio is an innovative biotechnology service company focused on drug target discovery and mechanism validation, providing solutions from target discovery to mechanism validation for new drug development, modernization of traditional Chinese medicine, and natural product research. We integrate drug targeting technologies such as ABPP, TPP, Lip-MS, cross-linking mass spectrometry, Lip-MS+molecular docking to identify drug target interaction sites, SPR/MST/BLI/ITC/DSF to detect drug target affinity platforms, protein chips, Olink multi factor high-throughput screening and detection platforms, small nucleic acid drug synthesis, and organoid screening core technologies to provide customers with high-precision compound target identification, binding site analysis, affinity validation, and functional validation services. Principles and core advantages of SPR technology Technical Principles Surface Plasmon Resonance (SPR) is a real-time label free biomolecule interaction detection technology based on metal dielectric interface optical effects, and is currently recognized as the gold standard for quantitative analysis of intermolecular binding dynamics. The core principle is that polarized light illuminates the gold/silver nanofilm on the surface of the chip at a specific angle, exciting free electrons to form surface plasmon waves. At this point, the reflected light intensity drops sharply, forming a characteristic resonance angle; When the ligand molecules fixed on the surface of the film bind to the analyte molecules flowing through, the refractive index around the film undergoes a slight change, and the resonance angle shifts accordingly. The shift is converted into response units (RU, 1 RU ≈ 1pg/mm ² mass change), ultimately generating a real-time binding dissociation kinetic curve. The three core parameters of binding rate constant (ka), dissociation rate constant (kd), and equilibrium dissociation constant (KD=kd/ka) are accurately calculated. Core advantages Compared to similar molecular interaction technologies such as MST, ITC, BLI, etc., SPR has three irreplaceable advantages: firstly, it has no labeling interference, does not require fluorescence or isotope labeling, maximally preserves the natural conformation and biological activity of the molecule, and avoids false positive results caused by labeling; Secondly, the dynamic detection accuracy is high, which can track the dynamic process of molecular binding and dissociation throughout the process, accurately distinguishing the interaction characteristics of "rapid binding and rapid dissociation" and "slow binding and long-term effects"; The third is the combination of throughput and cost-effectiveness. Regenerative sensor chips can achieve multiple repeated detections, significantly reducing the cost of single sample detection, and high throughput is suitable for large-scale sample screening. Compared with traditional enzyme activity experiments and mass spectrometry detection, SPR shows a correlation of over 99% and a 3-5 fold increase in detection efficiency when determining the kinetic parameter kinact/ki of covalent inhibitors. The core advantages of SPR technology in experimental application scenarios SPR technology, with its precision and versatility, has become a cross disciplinary core detection method in biomedical research, covering key experimental directions such as drug development, target validation, natural product screening, and membrane protein research. The core application scenarios are as follows: 1. Quantitative analysis of biomolecule interactions: applicable to various interaction systems such as protein-protein, protein small molecule, protein nucleic acid, antigen antibody, etc., it can accurately determine binding affinity and kinetic parameters, providing direct data support for the study of intermolecular interaction mechanisms; 2. Drug target validation and site analysis: Direct binding validation of candidate targets is performed, combined with site directed mutagenesis technology to locate key binding amino acid sites between drugs and targets, providing molecular basis for drug structure optimization; 3. Screening of active ingredients in natural products: Targeted screening of active monomers that bind to target proteins from complex systems such as plant extracts and microbial metabolites, achieving an integrated "screening validation identification" process and significantly reducing false positive rates; 4. Research on membrane protein interactions: Innovative strategies such as lipid nanodisks and SpyTag/SpyCatcher covalent fixation are used to solve the technical bottleneck of membrane protein inactivation and difficult fixation in vitro, and to achieve the detection of membrane protein targets such as GPCR and ion channels; 5. Covalent inhibitor kinetic characterization: It can quickly determine the kinact/ki value of irreversible covalent inhibitors. Compared with traditional enzyme activity experiments and mass spectrometry methods, the detection time is reduced by 60%, and the cost is reduced by more than 70%. Classic application cases and scientific research results of SPR technology Case 1: Molecular Interaction Verification in the Pathogenesis of Vitiligo In the study of the mechanism between gut microbiota and vitiligo skin lesions, the research team used SPR technology to verify the direct binding between metabolite hippuric acid and oxidative stress-related proteins. The experiment immobilized NOS2, MPO, and MAPK14 proteins on SPR chips, and dynamic detection was performed using hippuric acid as the analyte. The results showed that the binding affinity of hippuric acid to NOS2 was KD=32.05 μ M, and to MAPK14 was KD=14.24 μ M, and both binding processes showed concentration dependence, while no significant binding signal was detected to MPO. This result directly confirms that uric acid can regulate skin oxidative stress by targeting NOS2 and MAPK14, providing key molecular evidence for the gut skin axis regulation mechanism of vitiligo. Relevant studies have been published in Microbiome (IF=12.7). Case 2: Screening and identification of uric acid lowering active ingredients in natural products Using xanthine oxidase (XO) as the target protein for anti gout drugs, the research team used SPR technology to screen active ingredients from red kidney bean extracts. XO was fixed on the CM5 chip by amine coupling method, with gradient diluted extract as the analyte and allopurinol as the positive control. The results showed that the binding response value of a certain component in the extract to XO was significantly higher than that of the negative control, and the binding kinetics were stable (ka=3.1 × 10 ⁵ M ⁻¹ s ⁻¹, kd=1.2 × 10 ⁻³ s ⁻¹). By combining SPR and mass spectrometry techniques, the component was identified as Dp-3G, which binds to XO at KD=0.32 μ M. After mutating the FAD active site of XO, the SPR binding signal decreased by 92%, confirming its targeted binding to the XO active site to exert uric acid lowering effects. Compared with traditional ELISA screening, this study eliminates the small molecule labeling step, improves detection efficiency by 4 times, and reduces false positive rate by 80%. Case 3: Biosensing Applications of Portable SPR Sensors A compact SPR sensor developed based on laser interference lithography technology has achieved high sensitivity and rapid detection of biomolecules. The sensor uses a 781nm periodic silver nano grating, with a refractive index detection sensitivity of 715.5nm/RIU and a resolution of 3.91 × 10 ⁻⁵ RIU. The detection limit for human IgG is as low as 14.35nM, which is two orders of magnitude lower than traditional ELISA methods. In food safety testing, the sensor has a detection limit of 0.5pM for Escherichia coli O157: H7, with a detection time of less than 2 minutes, which is 20 times more efficient than traditional cultivation methods; In blood glucose monitoring, the sampling volume is less than 50 μ L, the cost of a single test is less than 0.02 US dollars, and the total cost is reduced by 82% compared to traditional laboratory testing. This technology breaks through the bottleneck of large volume and high cost of traditional SPR equipment, providing a new solution for rapid on-site detection. SPR technology, with its core advantages of label free, real-time dynamic, and high precision, has become the gold standard for research on biomolecule interactions. Its applications have extended from basic scientific research to drug development, clinical diagnosis, food safety, and other fields, especially playing an irreplaceable role in cutting-edge directions such as covalent inhibitor development, membrane protein target research, and natural product screening. With the technological upgrades of miniaturization of sensor chips, portability of detection systems, and multi-channel high-throughput, SPR technology will further lower the detection threshold and achieve full coverage from laboratory precision detection to on-site rapid screening. In the field of biopharmaceutical research and development, SPR technology will continue to serve as a core tool for target validation, drug screening, and mechanism research, providing more efficient and accurate molecular data support for innovative drug development and promoting the full chain technology upgrade from "targeted discovery" to "clinical translation". 划译