Nucleic Acid-metal Nanoparticles In Cell Imaging Analysis

The nanomaterial has been attracting a lot of attention in every field due to its unique properties.The noble metal nano-particles are widely developed and utilized in the aspects of biochemical sensing,biological imaging and biological monitoring due to their good physicochemical properties and biocompatibility.Utilizing the local surface plasmon resonance effect,quantum size effect and surface characteristics of noble metal nanoparticles,combined with high sensitivity dark field imaging technology,it is of great significance for the analysis and detection of intracellular biological processes.Based on this,the asymmetric modification of gold nanoparticles was carried out,and a series of stable and well-targeted modified probes were constructed,and their properties and applications in biomolecules were explored.The main research contents are as follows:1.When modified AuNPs are introduced as probes,plasma dimers with stronger scattering efficiency can be formed in the presence of the target.After AuNPs modified using azide-and alkyne-respectively,the Cu⁺catalyzed cycloaddition reaction forming AuNPs dimers.After Au₁-N₃ and Au₂-C?C are injected into sample,the dark-field situ imaging of Cu²⁺in rat serum and cells will be constructed.To overcome nonspecific to biomolecules,we proposed DNA/Au₁-N₃ probe and Anti-HER2/Au₂-C?C probe to DFM for HER2 protein on cells.Anti-HER2 modified Au₂-C?C,can not only combined with HER2 protein specificity,but also form an effective LSPR region on the target protein after binding to AuNPs.By controlling the rolling circle amplification?RCA?product tomatch the expression zone of the HER2protein-specific aptamer,DNA/Au₁-N₃ was hybridzed by RCA product and could link the Anti-HER2/Au₂-C?C via a click reaction.So an efficient visible plasmonic polymer can be produce.2.To recognize ATP specifically,a designed DNA1?containing ATP aptamer sequences?waschosentoattachonmagneticbeads?MB?asthecaptureprobe.MB/DNA1/DNA2/Au₁-?E?cyclooctene probe?MB/Au₁?was constituted by DNA1/DNA2hybridization.In the meantime,these structure of MB/Au₁ formed steric resistance to avoid a contact between-?E?cyclooctene on Au₁ and-N₄ on Au₃.After DNA1 combining with ATP,DNA2/Au₁-?E?cyclooctene was released from MB/Au₁ probe and can react with Au₃-N₄ probe to produce AuNPs polymers,which led to AuNP close to each other and color changed from pink to gray for visual quantitative.This strategy will be widely used in the identification and determination of nanoparticles in biological imaging and analysis.3.A versatile cellular signal amplification approach,integrating biodegradable MnO₂nanosheet with target-triggered DNAzyme recycling amplification in one nanosystem,was designed for highly specific and sensitive imaging analysis of microRNAs in living cells.In summary,this paper combines nanomaterials and imaging techniques to place analytical and detection studies on the nanoscale,enabling the detection of specificity and specificity of biomolecules in vivo.This is of great significance for the discovery and treatment of cancer in the future,providing theoretical basis and direction for future research.