Polyaniline assisted USB based sensor for determination of benzene biomarker

Benzene is a known Hemotoxic carcinogen for humans. The carcinogenic properties justify that any exposure to Benzene in ambient air needs to be monitored. Exposure to Benzene is indicated by presence of trans-trans Muconic Acid (ttMA) in urine of human as a biomarker. Currently the levels of biomarker are measured by sophisticated and costly equipment like High Precision Liquid Chromatography (HPLC). This commercial procedure is time consuming due to rigorous sample preparation, involvement of expensive equipment and need of expertise for analysis. To remedy this, USB assisted and Polyaniline (PANI) based point of care electrochemical sensor for detection of biomarker of Benzene is developed. To operate this system, one does not require sample preparation and trained hands.The system is USB based portable potentiostat which performs Linear Sweep Voltammetry (LSV) for detection of ttMA. The design comprises of potentiostat interfaced with microcontroller FRDM-KL 25Z of NXP semiconductors. The system detects nanoampere current with linear sweep voltage resolution of 800 μV. Graphical User Interface (GUI) facilitates to set the parameters like start potential, end potential, step size and scan rate of linear sweep voltage. The real time serial plotter equips the viewing and capture of real-time sensor data from electrochemical cell. The three-electrode electrochemical cell consists of PANI coated Aluminum as working, Graphite Pencil Electrode (GPE) as counter, and Saturated Calomel Electrode (SCE) as reference which is utilized for electrochemical detection of ttMA in urine sample.This system is capable of detecting ttMA in Urine which corresponds to intermediate (1-5 ppm) and high (>5 ppm) level exposure of Benzene in ambient air. Keywords: Linear sweep voltammetry, Trans trans muconic acid, Serial plotter, EM PANI, Graphical user interfac

Sensibility of polyaniline nanofibers to biomarker of benzene recognized as a carcinogen

Alarming situation of toxic substances such as benzene and its analogs in the environment and workplaces, making it important to monitor these chemicals and their metabolites in order to evaluate risk hazards and potential problems caused by exposure to toxic compounds. Benzene is omnipresent in usage across industries. International Agency for Research on Cancer (IARC) which is a part of World Health Organization (WHO) has classified Benzene as a human carcinogen. trans-trans Muconic acid (ttMA) is the most important biomarker of benzene for biomonitoring of its low level exposure. In this paper the sensing ability of polyaniline (PANI) to ttMA is investigated for development of cheap, portable and effective electrochemical biosensor. To take this ahead for biosensor device application, successful self-assembling of PANI nanofibers of 40–70 nm range on SS 304 working electrode was achieved. Fourier transform infrared spectroscopy and X-ray diffraction was used to characterize the chemical structure of PANI. Morphology of sample was observed by field emission gun scanning electron microscopy (FEG-SEM). The detection potential of ttMA in phosphate buffer solution of pH 5.8 acting as a supporting electrolyte was found to be at 0.26 V by linear sweep voltammetry