Developing active targeting strategies for agrochemical delivery is paramount for simultaneously enhancing fungicide efficacy and mitigating off-target environmental risks. This study reports the development of wheat germ agglutinin (WGA)-functionalized mesoporous silica nanoparticles (MSNs) as a nanocarrier system designed to actively target fungal cell walls. These MSNs were loaded with the fungicide Fluazinam (Flu) to yield Flu@MSNs-WGA, which exhibited an average hydrodynamic diameter of 44.54 nm and a Fluazinam loading content of 10.89 % ± 0.27 %. Studies investigating transport and distribution in rice plants demonstrated that the WGA-functionalized nanoparticles were absorbed by roots and leaves and exhibited specific accumulation at sites of Rhizoctonia solani infection, confirming active targeting. Furthermore, In vitro assays revealed that the antifungal activity of Flu@MSNs-WGA against R. solani was significantly enhanced compared to the non-targeted nanocarrier (Flu@MSNs-COOH) and was 2.7 times higher than that of a commercial Fluazinam suspension concentrate (Flu SC) formulation. Representing the first application of WGA for targeted pesticide delivery, this work validates the feasibility of this approach, providing essential proof-of-concept and technical support for developing novel, actively targeted nano-pesticides for improved crop protection.
O-GlcNAcylation is a very important post-translational modification of nucleocytoplasmic proteins. Aberrant O-GlcNacylation has been found in a variety of human diseases including many types of cancers, diabetes, and Alzheimer's disease. However, analysis of protein O-GlcNacylation still remains a great challenge due to its low levels and labile nature. Herein, a highly sensitive and reliable colorimetric method is developed by use of wheat germ agglutinin (WGA) lectin for specific recognition of O-GlcNAc and gold nanoparticle (AuNP)-catalyzed copper deposition for signal amplification. In presence of the target molecule, AuNP is specifically introduced onto the sensing surface and then catalyzes the copper deposition. An Au@Cu core–shell structure is produced from the deposition. The obtained copper shell on AuNP is dissolved by FeCl3 due to the oxidation–reduction reaction between copper and Fe3+, resulting in Cu2+ and Fe2+, which subsequently form a red coordination complex in the presence of bathophenanthrolinedisulfonic acid disodium salt (BPT2−). Thus, the amount of the red complex is proportional to the level of O-GlcNAc. Qualitative O-GlcNAc detection is realized by direct readout with the naked eye, while the quantitative analysis is achieved by measurement of the absorbance using a UV-Vis spectrophotometer. With increasing time, more and more copper is deposited on the surface of AuNP, thus achieving significant signal amplification. Under optimal conditions, an ultralow limit of detection (LOD) down to 0.02 pg mL−1 is achieved with GlcNAc-conjugated BSA as a model analyte. The developed platform was also successfully applied to analyze O-GlcNAcylation levels in prostate cancer cell line PC-3 and normal cell line RWPE-1. The results obtained by the proposed method are in good agreement with the data from protein microarray assays, demonstrating its great potential for sensitive and reliable O-GlcNAcaylation detection in fundamental research and in cancer diagnosis.
Yang Guotai,Huang Min,Wang Yutong,Chen Guanhua,Zhao Yu,Xu Hengyi
A lectin magnetic separation (LMS) method for Staphylococcus aureus ( S. aureus ) was developed with the aim to improve the efficiency of magnetic nanoparticles and to expand the scope of bacterial recognition. Poly(ethylene glycol) (PEG)-mediated magnetic nanoparticles modified with streptavidin (MNP-PEG-SA) were synthesized and then applied to a two-step LMS based on the use of wheat germ agglutinin (WGA). Three specific methods for S. aureus detection (suitable for different requirements including detection time and sensitivity) were designed. The new LMS has improved anchoring efficiency (compared to two-step LMS methods) and requires a reduced number of magnetic particles. The Baird–Parker (B-P) method can detect S. aureus with a detection limit of 3 × 10 0 CFU·mL −1 within 15 h; the polymerase chain reaction (PCR) method can be finished within 4 h, with the lowest detection limit (LOD) of 3 × 10 2 CFU·mL −1 . The LOD of HRP-pig IgG-based colorimetric method is 3 × 10 5 CFU·mL −1 , and the method only lasts for 2 h. If combined with specific detection methods, it meets different needs for rapid detection of S. aureus .
Schematic representation of lectin magnetic separation (LMS) based on biotin-wheat germ agglutinin (WGA) and poly (ethylene glycol) (PEG)-mediated streptavidin-modified magnetic nanoparticles (MNP-PEG-SA) and three different quantification strategies (including B-P culture assay, PCR assay, and colorimetric assay) for S. aureus .
Guotai Yang,Xiangyu Meng,Yutong Wang,Mingyao Yan,Zoraida P. Aguilar,Hengyi Xu
A novel 2-step lectin-magnetic separation (LMS) method combined with gold nanoparticle (AuNPs) -based colorimetric system for specifically and quantitatively detecting S. aureus in blood samples was established. In this study, wheat germ agglutinin lectin from Triticum vulgaris (wheat) (WGA) was applied for the first time as a recognition agent in a 2-step magnetic separation method using magnetic nanoparticles (MNPs) for effective and low-cost bacteria enrichment. A quantitative detection strategy based on the long dsDNA amplicons stabilized with AuNPs against salt-induced aggregation was investigated. The 2-step LMS method resulted in a high enrichment efficiency even at low concentrations (10 0 –10 2 CFU/mL) of S. aureus in pure culture and blood samples. The AuNPs-based colorimetric system was applied for quantitative detection of S. aureus with a limit of detection (LOD) at 3.5 × 10 0 CFU/mL. The complete process starting with the blood samples treatment, 2-step LMS, and AuNPs-based colorimetric detection took only 7 h. The low cost and sensitive 2-step LMS combined with AuNPs-based colorimetric detection holds considerable potential for early sepsis diagnosis.
危险品化学品经营许可证（带存储）