One of the major disadvantages of common Fluorescent Immunoassays is the Fluorophore per Protein ratio. In the normal settings several fluorophores such as FITC are covalently linked to one specific antibody. The problem which occurs with an increased number of fluorescent molecules per binding event is an appearing quenching effect and with this a decrease of fluorescence and signal. To overcome this weakness of Fluorescent Immunoassays, different types of organic fluorescent nanoparticles were fabricated with an easy one step top down method, using cavitation forces for breaking down larger fluorophore powder. After the fabrication and well characterization, two of the chosen fluorophores were aggregation induce emissive: TPEDH and novel scaffold TPEA. The other non-direct fluorophore...[ Read more ]

One of the major disadvantages of common Fluorescent Immunoassays is the Fluorophore per Protein ratio. In the normal settings several fluorophores such as FITC are covalently linked to one specific antibody. The problem which occurs with an increased number of fluorescent molecules per binding event is an appearing quenching effect and with this a decrease of fluorescence and signal. To overcome this weakness of Fluorescent Immunoassays, different types of organic fluorescent nanoparticles were fabricated with an easy one step top down method, using cavitation forces for breaking down larger fluorophore powder. After the fabrication and well characterization, two of the chosen fluorophores were aggregation induce emissive: TPEDH and novel scaffold TPEA. The other non-direct fluorophore is FDA which fabricated nanoparticles react to single fluorescent molecules after a hydrolyzation. All types of fabricated fluorescent nanoparticles were physical or covalent functionalized with antibodies for potential applications. Targeting the AIE related nanoparticles, they were applied separately on a developed paper pad immunoassay which was pre tested with different paper membranes and HRP for enzymatic signal generation. Using AIE nanoparticles for signal generation, it was possible to develop immunoassay in microgram and nanogram per millilitre antigen range with good linear regression. Further as a second way of application, FDA nanoparticles were applied in a PDMS multiplex lateral flow system which was first tested with an anti-cardiolipin assay. The speciality of the PDMS test is the enhancement of surface area by filling up a detection zone by deposition of labelled particles. Using FDA nanoparticles in a separate PDMS lateral flow assay, its strong fluorescence signal after triggered reaction could be analysed with good linearity. Overall, the aim of nanoparticle fabrication and application in low cost assay systems was achieved throughout the progress.