SERS-Based Biosensors Combined with Machine Learning for Medical Application.

Surface-enhanced Raman spectroscopy (SERS) has shown strength in non-invasive, rapid, trace analysis and has been used in many fields in medicine. Machine learning (ML) is an algorithm that can imitate human learning styles and structure existing content with the knowledge to effectively improve learning efficiency. Integrating SERS and ML can have a promising future in the medical field. In this review, we summarize the applications of SERS combined with ML in recent years, such as the recognition of biological molecules, rapid diagnosis of diseases, developing of new immunoassay techniques, and enhancing SERS capabilities in semi-quantitative measurements. Ultimately, the possible opportunities and challenges of combining SERS with ML are addressed.

Crown monitoring: Trace the dynamic changes of caspase-3 and H2O2 in real-time imaging based on FRET/SERS.

Caspase-3 and hydrogen peroxide (H2O2) are closely associated with numerous diseases, both of them are vital in different physiological and pathological conditions. They are closely related and also can act independently. The selective and accurate determination of caspase-3 and H2O2 simultaneously to determine their state of being in different situations is of great significance for further study of their molecular mechanisms and the elucidation of their biological functions. In our latest research, a AuNPL-crown nanoprobe was obtained by attaching (4-aminosulfonylphenyl) boronic acid (4-APBA) and peptide-FITC (NH2-Asp-Glu-Val-Asp (DEVD)-FITC) to gold nanoplates (AuNPLs). The fabricated AuNPL-crown nanoprobe was used for dual-channel and real-time tracking of the dynamic changes in caspase-3 and H2O2 based on fluorescence resonance energy transfer (FRET)/surface-enhanced Raman spectroscopy (SERS) technology. The AuNPL-crown nanoprobe not only provides synergy but can also achieve noninterference, making the results more reliable and repeatable. This study simultaneously traced the dynamic changes of caspase-3 and H2O2 on a single probe, which provides a potential new platform for the analysis of caspase-3 and H2O2 in the biological environment with high accuracy, sensitivity, convenience, and efficiency. In summary, we develop a new strategy for the simultaneous detection of different substances on a single probe.

Detection of cell-surface sialic acids and photodynamic eradication of cancer cells using dye-modified polydopamine-coated gold nanobipyramids.

A nanoprobe based on polydopamine-coated gold nanobipyramids surface modified with molecules of a phenylboronic acid-substituted distyryl boron dipyrromethene has been fabricated and characterised using various physical and spectroscopic methods. It serves as an ultrasensitive sensor for sialic acids on the surface of cancer cells based on its dual surface-enhanced Raman scattering and fluorescence response. This biomarker can also trigger the photodynamic activity of these nanobipyramids, effectively eradicating the cancer cells mainly through apoptosis as shown by various bioassays.

A green electrolysis of silver-decorated MoS2 nanocomposite with an enhanced antibacterial effect and low cytotoxicity.

To tackle the devastating microbial infections for the public health, a continuous search for effective and safe nanobiocides based on their prominent nanoscale effects has been extensively explored during past decades. In this study, a green electrolysis method was employed to synthesize silver-doped molybdenum sulfide (Ag@MoS2) composite materials. The obtained nanocomposites exhibited a sheet-like structure with a large specific surface area, which contributed to the efficient loading and refined distribution of silver nanoparticles. G- E. coli and G + S. aureus were used as model bacteria for the antibacterial test, which revealed enhanced antibacterial activity of produced nanocomposites with an identified destructive effect on preformed biofilms. It was found that within 72 hour incubation, 20 µg mL-1 Ag@MoS2 was sufficient to inhibit the growth of E. coli and S. aureus without visible colony formation, pointing to a desirable long-term antibacterial activity. Further a mechanistic antibiosis study of Ag@MoS2 indicated the involvement of a generation of reactive oxygen species. Notably, owing to the well-distributed silver nanoparticles on the nontoxic MoS2 nanosheet, the cytotoxicity evaluation results revealed that produced nanocomposites exhibited negligible toxicity to mammalian cells, and thereby held promising potential for biomedical applications.

A Gold Nanoparticle Bouquet held on plasma membrane: An ultrasensitive dark-field imaging approach for Cancer Cell Analysis.

Rational: p53 is suppressing tumor protein correlated with the cell cycle factors and apoptosis. Here, a gold nanoparticle bouquet is designed for an ultrasensitive dark-field imaging approach for cancer cell analysis. Methods: AuNP60/APBA is functionalized by a gold nanoparticle bouquet-plasmonic 60 nm gold nanoparticles. And consistent APBA can be held on the plasma membrane. After 13 nm gold nanoparticles are functionalized with mannose (AuNP13/MN), the AuNP60/APBA gold nanoparticles are captured. The absorption spectrum of aggregation gold nanoparticles (AuNPs) shifts to near-infrared (NIR) region which can be observed under dark-field microscopy (DFM) and is treated the subsequent with photothermal therapy. Results: The results that MCF-7 cells were successfully destroyed under the near-infrared (NIR) irradiation and the intracellular WTp53 increased while the MTp53 decreased. These results indicated that p53 is the key molecule in the apoptosis signaling pathway. Photothermal therapy can stimulate the MTp53 in the cell signal conductive pathway. Conclusion: This work offers a new method for intracellular p53 analysis and a potential targeted cancer treatment.