Tunable Signal-Off and Signal-On Electrochemical Cisplatin Sensor

Yao Wu, Rebecca Y. Lai

Research output: Contribution to journalArticlepeer-review


We report the first electrochemical cisplatin sensor fabricated with a thiolated and methylene blue (MB)-modified oligo-adenine (A)-guanine (G) DNA probe. Depending on the probe coverage, the sensor can behave as a signal-off or signal-on sensor. For the high-coverage sensor, formation of intrastrand Pt(II)-AG adducts rigidifies the oligo-AG probe, resulting in a concentration-dependent decrease in the MB signal. For the low-coverage sensor, the increase in probe-to-probe spacing enables binding of cisplatin via the intrastrand GNG motif (N = A), generating a bend in the probe which results in an increase in the MB current. Although both high-coverage signal-off and low-coverage signal-on sensors are capable of detecting cisplatin, the signal-on sensing mechanism is better suited for real time analysis of cisplatin. The low-coverage sensor has a lower limit of detection, wider optimal AC frequency range, and faster response time. It has high specificity for cisplatin and potentially other Pt(II) drugs and does not cross-react with satraplatin, a Pt(IV) prodrug. It is also selective enough to be employed directly in 50% saliva and 50% urine. This detection strategy may offer a new approach for sensitive and real time analysis of cisplatin in clinical samples.

Original languageEnglish (US)
Pages (from-to)9984-9989
Number of pages6
JournalAnalytical Chemistry
Issue number18
StatePublished - Sep 19 2017
Externally publishedYes

ASJC Scopus subject areas

  • Analytical Chemistry


Dive into the research topics of 'Tunable Signal-Off and Signal-On Electrochemical Cisplatin Sensor'. Together they form a unique fingerprint.

Cite this