Rapid and molecular selective electrochemical sensing of phthalates in aqueous solution

Asif I. Zia, Subhas Chandra Mukhopadhyay, Paklam Yu, Ibrahim H. Al-Bahadly, Chinthaka Pasan Gooneratne, Jürgen Kosel

Research output: Contribution to journalArticlepeer-review

44 Scopus citations


Reported research work presents real time non-invasive detection of phthalates in spiked aqueous samples by employing electrochemical impedance spectroscopy (EIS) technique incorporating a novel interdigital capacitive sensor with multiple sensing thin film gold micro-electrodes fabricated on native silicon dioxide layer grown on semiconducting single crystal silicon wafer. The sensing surface was functionalized by a self-assembled monolayer of 3-aminopropyltrietoxysilane (APTES) with embedded molecular imprinted polymer (MIP) to introduce selectivity for the di(2-ethylhexyl) phthalate (DEHP) molecule. Various concentrations (1-100. ppm) of DEHP in deionized MilliQ water were tested using the functionalized sensing surface to capture the analyte. Frequency response analyzer (FRA) algorithm was used to obtain impedance spectra so as to determine sample conductance and capacitance for evaluation of phthalate concentration in the sample solution. Spectrum analysis algorithm interpreted the experimentally obtained impedance spectra by applying complex nonlinear least square (CNLS) curve fitting in order to obtain electrochemical equivalent circuit and corresponding circuit parameters describing the kinetics of the electrochemical cell. Principal component analysis was applied to deduce the effects of surface immobilized molecular imprinted polymer layer on the evaluated circuit parameters and its electrical response. The results obtained by the testing system were validated using commercially available high performance liquid chromatography diode array detector system.
Original languageEnglish (US)
Pages (from-to)342-349
Number of pages8
JournalBiosensors and Bioelectronics
StatePublished - May 2015

ASJC Scopus subject areas

  • Biomedical Engineering
  • Electrochemistry
  • Biotechnology
  • Biophysics


Dive into the research topics of 'Rapid and molecular selective electrochemical sensing of phthalates in aqueous solution'. Together they form a unique fingerprint.

Cite this