Nanozymes featuring a mesoporous silica shell for rapid enrichment and ultrasensitive lateral flow immunoassay of influenza A

• Published in: Analytica chimica acta 2025-01, Vol.1335, p.343474, Article 343474
• Main Authors: Liang, Jing, Liu, Xiaoxian, Liu, Zhenzhen, Xu, Xuanming, Sun, Yinuo, Chen, Yuan, Xiao, Rui, Wang, Yajie
• Format: Article
• Language: English
• Subjects: Colorimetric; Colorimetry - methods; Composite nanozymes; Humans; Immunoassay - methods; Influenza A; Influenza A virus - immunology; Influenza A virus - isolation & purification; Influenza A Virus, H1N1 Subtype - immunology; Influenza A Virus, H1N1 Subtype - isolation & purification; Influenza, Human - diagnosis; Lateral flow immunoassay; Limit of Detection; Mesoporous material; Platinum - chemistry; Porosity; Silicon Dioxide - chemistry
• ISSN: 0003-2670; 1873-4324; 1873-4324
• DOI: 10.1016/j.aca.2024.343474

Respiratory illnesses stemming from influenza A viruses represent a significant worldwide health concern. There is an immediate need for a rapid and sensitive method to detect influenza A viruses early, without requiring extra equipment. Here, we established a lateral flow immunoassay (LFIA) for the detection of influenza A (Flu A) using a "three-in-one" multifunctional mesoporous Fe3O4@SiO2@Pt nanozymes (Fe3O4@MSiO2@Pt NZs) with excellent magnetic separation properties, colorimetric, and peroxidase-like (POD-like) activities. Effective enrichment of target Flu A in complex samples as well as greater loading of Pt particles by mesoporous structures with large specific surface area to enhance POD-like activity can significantly improve the detection sensitivity of the LFIA. After colorimetric amplification by Fe3O4@MSiO2@Pt tags catalysis, the qualitative and quantitative results of detection for Flu A nucleoprotein (Flu A-NP) were 0.01 and 0.0089 ng mL−1, respectively. This indicated a sensitivity approximately 100 times greater than commercially available colloidal Au nanoparticle (AuNP)-based LFIA strips. For detection of inactivated H1N1 virus, quantification can be as low as 33 copies mL−1. Moreover, it demonstrated high accuracy in pharyngeal swab sample simulation experiments. Therefore, the proposed platform based on Fe3O4@MSiO2@Pt NZs-LFIA offered a promising approach for point-of-care testing (POCT), enabling rapid and ultrasensitive diagnosis of Flu A. [Display omitted] •Controlled-thickness mesoporous SiO2 layers provide high stability and larger surface area.•The synthesized Fe3O4@MSiO2@Pt NZs have superior magnetic, colorimetric, and POD-like activity.•Fe3O4@MSiO2@Pt NZs were used to construct LFIA with good sensitivity, specificity and accuracy.•The method's detection limit surpasses commercial colloidal AuNP-based LFIA strips by 100-times.