Investigation Of New Biosensing Based On Multifunctional Protein Nanowire

Nanotechnology refer to investigating and exploring the property and application of materials on the nanometer scale.According to the concept of nanotechnology,prions belong to natural nanomaterials.This noble nanomaterial has attracted extention attention owingto its high ordered,chemical stability and larger surface based on prion self-assembling and widely used in multifunctional nanomaterial investigating.Here,a preparation method for multifunctional protein nanowires has established based on controllable self-assembling by magnetic sepration.And a magnetic bead-nanowire 3D composite and a fluorescence barcode nanowire are constructed by this method,respectively.Bsed on above,the highly effective pathogen capturing method has been developed,which significantly improve the sensitivity of the pathogen detection.Firstly,a magnetic bead-nanowires composite engineering for 3D diagnosis.The composite was constructed by biotinylation seed-induced self-assembling of the yeast prion domain that genetically fused with HIV-1 p24 antigen protein and protein G(SPG)on the streptavidin modified magenetic beads,resulting p24 antigen could be immobilized on the three-dimensional(3D)surface.The hight densty of the receptor,displayed on the 3D composite,could be more affinity and specificity to the ligands because of multivalent effect.As a result,100-fold enhancement of the sensitivity compared with tranditional ELISA when applied in detecting HIV-1 p24 antibody,the limit of detection was 0.1 ng/mL.Moreover,the time of detection could be reduced less than 30 min because of separation based on magnetic beads.Based on this model,the magnetic bead-nanowire 3D composite was applied in sandwich ELISA modol to detect HIV-1 p24 antigen.The sensitivity of this model reach at 1 ng/mL.Secondly,a fluorescence barcode nanowire was obtained by displaying different fluorescent proteins on the protein nanowire based on stepwise self-assembling.Three-segment(green-red-green)pattern had be observed in the co-localization image of fluorescence nanowires by ordinary fluorescence microscope.The novel fluorescence barcode nanowire has great potentials for multiplexed,high-throughput and conveniently detection of biomolecules.This method provides a new idea for constructing the fluorescence barcode probes.