RESUMEN
Pesticides are biological or chemical substances used to manage pests and diseases. Encapsulation of pesticides in biodegradable carriers creates a slow-release system that can improve water dispersibility and prolong residual activity. We prepared two kinds of poly (lactic-co-glycolic acid)(PLGA) nanoparticles (NPs) with polyvinyl alcohol (PVA) and sodium dodecyl sulfate (SDS) surfactants. These were used to encapsulate the fungicide fluazinam (Flu) against Rhizoctonia solani using the Shirasu Porous Glass (SPG) membrane emulsification method. Both nanoparticles had uniform spherical shapes with average diameters of 314.13 nm (SDS) and 612.80 nm (PVA). The slow-release microspheres had excellent sustained-release properties, resistance to UV degradation, storage stability, leaf surface coverage and antifungal efficacy compared to the commercial formulation.
Asunto(s)
Aminopiridinas/farmacocinética , Fungicidas Industriales/farmacocinética , Nanopartículas/química , Copolímero de Ácido Poliláctico-Ácido Poliglicólico/química , Aminopiridinas/farmacología , Fungicidas Industriales/farmacología , Microesferas , Tamaño de la Partícula , Copolímero de Ácido Poliláctico-Ácido Poliglicólico/metabolismo , Alcohol Polivinílico/química , Porosidad , Rhizoctonia/efectos de los fármacos , Dodecil Sulfato de Sodio/química , Espectrofotometría Ultravioleta , Tensoactivos/químicaRESUMEN
Aggregation-induced emission luminogens (AIEgens) have attracted considerable interest for application towards the development of various biosensors due to their unique optical properties. However, the major challenge associated with generating a suitable fluorescent signal for constructing an AIEgens-based immunoassay platform, is the complex surface modification and additional chemical reaction required to activate the AIE process. This work reports a novel AIEgens nanobeads-based fluorescence-linked immunosorbent assay (FLISA) platform wherein the fluorescent labels are hexaphenylsilole (HPS) nanobeads, which were synthesized through Shirasu porous glass (SPG) membrane emulsification method and could provide a strong, direct fluorescent signal without any pretreatment. Moreover, the particle-based signal amplification effect affords this platform significantly improved detection sensitivity for carcinoembryonic antigen (CEA) quantitation. Compared to FLISA which uses R-phycoerythrin (PE) or commercial green QDs nanobeads as fluorescent labels, this AIEgens nanobeads-based FLISA platform exhibits detection sensitivity improved up to 45-fold and 12-fold, respectively. Clinical validation experiments applying this AIEgens nanobeads-based FLISA immunoassay platform to analyze human serum samples produce results consistent with those obtained by the clinical gold-standard method, electrochemiluminescence immunoassay (ECLIA). The strong photobleaching resistance and excellent fluorescent stability of the HPS nanobeads negate the need for light shielding, which improves the efficiency and makes the operating conditions more comfortable. Thus, this AIEgens nanobeads-based FLISA platform, with attractive features including direct fluorescent signal generation and significant signal amplification, creates a new, versatile route for the application of AIEgens in biosensors and clinical diagnosis.
Asunto(s)
Anticuerpos Inmovilizados/química , Antígeno Carcinoembrionario/sangre , Colorantes Fluorescentes/química , Técnicas de Inmunoadsorción , Nanopartículas/química , Técnicas Biosensibles/métodos , Dimerización , Humanos , Inmunoadsorbentes/química , Nanopartículas/ultraestructuraRESUMEN
Suspension arrays based on optical encoded microspheres have attracted great attention for multiplexed detection in gene analysis, protein profiling, early disease diagnosis, treatment monitoring and so on. However, the fluorescence stability of barcodes and detection sensitivity require further improvement to meet the increasing demands of "precision diagnosis". Methods: This work reports a novel suspension array platform based on extremely stable AIEgens (AIE33 and AIE NIR800) microbeads as barcodes and AIEgens (1,1,2,3,4,5-Hexaphenyl-1H-silole, HPS) nanobeads as fluorescent signal reporter coupled with flow cytometry for multiplexed detection. Results: Due to the excellent fluorescent signal amplification effect of the HPS nanobeads, our multiplex assay showed enhanced detection sensitivity, compared to multiplex assay using QDs nanobeads (up to 3-fold improvement) and commercial organic dye of phycoerythrin (up to 5-fold improvement) as the fluorescent signal reporters. Conclusion: Furthermore, validating experiments showed similar detection performance to the clinical gold-standard method of ImmunoCAP for allergen detection in patient serum samples, demonstrating the suspension array platform based on AIEgens microbeads with excellent fluorescence stability and AIEgens nanobeads with strong signal amplification ability is promising for high-sensitivity multiplexed bioassay applications.