Long-range surface plasmon aptasensor for label-free monitoring of vancomycin

Koji Toma, Yui Satomura, Kenta Iitani, Takahiro Arakawa, Kohji Mitsubayashi

Research output: Contribution to journalArticlepeer-review


Vancomycin (VCM) causes poisoning symptoms at high concentrations; thus, therapeutic drug monitoring is recommended to measure and control blood levels regularly. However, blood analysis at regular intervals does not allow knowing the detailed temporal change in concentration. To address this challenge, we developed a long-range surface plasmon (LRSP) aptasensor for measuring VCM label-free and real-time by combining a sensitive LRSP sensor and a peptide aptamer with a VCM recognition site. First, three different biosensors for VCM were compared. One was prepared by immobilizing the peptide aptamer directly on (Direct-Apt) or via a self-assembled monolayer (SAM) on a gold surface (SAM-Apt). The other used anti-VCM antibodies immobilized on a gold surface via the SAM (SAM-Ab). The Direct-Apt showed larger sensor output to VCM than the other biosensors. The dynamic range for VCM was 0.78–100 μM, including the therapeutic range (6.9–13.8 μM). The Direct-Apt also showed the sensor output only from VCM among four different antibiotics, demonstrating the high selectivity for VCM. The VCM captured by the aptamer could be removed by rinsing with phosphate-buffered saline. The measurement was rapid, with 72- and 77-sec response and recovery times, allowing not only repeated but also real-time measurements. Finally, the Direct-Apt in 20% serum solutions showed comparable sensitivity to VCM in the buffer solution, indicating high capability for real-sample.

Original languageEnglish
Article number114959
JournalBiosensors and Bioelectronics
Publication statusPublished - 2023 Feb 15


  • Aptasensor
  • Surface plasmon
  • Therapeutic drug monitoring
  • Vancomycin

ASJC Scopus subject areas

  • Biotechnology
  • Biophysics
  • Biomedical Engineering
  • Electrochemistry


Dive into the research topics of 'Long-range surface plasmon aptasensor for label-free monitoring of vancomycin'. Together they form a unique fingerprint.

Cite this