Hormone mimics or endocrine disrupting compounds (EDCs) that may

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					      Detection of Endocrine Disrupting compounds by a Tyrosinase

                                       Biosensor

Endocrine disrupt compounds (EDCs) or environmental hormones are steroid-like

compounds that exist in nature or are produced during industrial process. EDCs, once

ingested, may interfere with the functions of normal endocrine system in both wildlife

and humans, becoming a major concern world wide. Hence, the development of a quick

and easy operated biosensing device is necessary. In this study, an electrochemical

biosensor for the detection of endocrine disrupt compounds based on tyrosinase

entrapped within gelatin film is designed and developed. The synthetic oestrogens and

phenolic compounds, the suspected endocrine disrupt compounds, including bisphenol A,

diethylstilbestrol (DES), paraben and 3-aminophenol are tested on the developed

biosensor. Amperometric response of biosensor to EDCs in a phosphate buffer at pH 6

was measured as a function of concentrations at fixed bias voltage of −0.2 V versus

Ag/AgCl.The electrode gives linear response range of 0.1 – 20 M, 10–100 M, 1–50

M and 20-100 M for bisphenol A, diethylstilbestrol (DES), 3-aminophenol and

paraben , respectively. The detection limit for bisphenol A, diethylstilbestrol (DES),

3-aminophenol and paraben are, nM, nM, 20 nM and 5 M, respectively. Moreover,

the developed biosensor exhibits a good reproducibility with a relative standard devision

(R.S.D) of 5.8 %.