Wentao Bai

Helicobacter pylori (H. pylori) infection is closely associated with the development of chronic gastritis, peptic ulcers, and gastric cancer, highlighting the importance of rapid and accurate detection for disease prevention and clinical management. In this study, a one-pot LAMP-CRISPR/Cas12b assay targeting the CagA gene was developed for H. pylori detection. First, the LAMP system was optimized by systematically screening key reaction components. Subsequently, a one-step LAMP-CRISPR/Cas12b detection platform was established through optimization of the ratio between the LAMP premix and CRISPR buffer, reaction temperature, Cas12b concentration, and ssDNA reporter concentration. Under optimal conditions, the assay achieved a detection limit of 3.14 × 10¹ copies/µL, representing a tenfold improvement in sensitivity compared with conventional LAMP and PCR assays (3.14 × 10² copies/µL). In addition, the entire detection process could be completed within 1 h. Validation using 17 culture-positive and 17 culture-negative samples demonstrated complete concordance with culture-based results, with no false-positive or false-negative detections observed. These findings indicate that the proposed platform possesses high sensitivity, excellent specificity, rapid turnaround, and operational simplicity, demonstrating strong potential for point-of-care testing and applications in resource-limited settings.

Pseudomonas aeruginosa (PA) is a significant pathogen of clinical concern that is frequently associated with multidrug resistance, leading to respiratory tract, wound, and hospital-acquired infections. To enable rapid and accurate detection, we developed a fluorescence-based loop-mediated isothermal amplification (LAMP) method, targeting the PA-specific ecfX gene. Among ten primer sets designed, the optimal set (EC2) was identified, and reaction conditions were optimized (Bst polymerase 320 U/mL, Mg²⁺ 8 mM, dNTP 1.4 mM, inner/outer primer ratio 1:8, 64 °C, 20 min). The assay demonstrated a detection limit that was comparable to a real-time polymerase chain reaction and immunochromatographic assays, but with a markedly reduced turnaround time. No cross-reactivity was observed with non-PA pathogens, and reproducibility tests confirmed high stability. In addition, the reliability of the results was further verified using 60 standard bacterial strains, and the feasibility of the assay was validated with 2 real soil samples and 1 water sample. This LAMP method offers a simple, rapid, and sensitive tool for on-site detection of PA, with potential applications in clinical diagnostics and public health surveillance.