DETERMINATION OF UREA IN BLOOD SERUM BY CONDUCTOMETRIC BIOSENSOR Screen Printed Carbon Electrode (SPCE) – NATA DE COCO

• Main Authors: Sendy Kurniawan, Dian Nur Fajariati, Helmi Auliyah Istiqomah, Oki Mandalia Antasari, Ani Mulyasuryani
• Format: Article
• Language: English
• Published: Jenderal Soedirman University 2011-11-01
• Series: Molekul
• Subjects: Conductometric biosensor; Nata de coco membrane; Urea in blood
• Online Access: http://www.jmolekul.com/downloads/10_2_97-103.pdf
• ISSN: 1907-9761; 1907-9761

Urea is byproduct of protein degradation in normal serum about 10.7 – 42.8 mg/dL. Conductometric biosensor for determination urea in blood serum based on hydrolysis reaction of urea by urease produce ammonia (NH3) and carbon dioxide (CO2) which will be ionized in water. The research, optimum condition of urease mass, nata de coco membrane thickness, and pH urea solution were studied for determination performance of biosensor while the biosensor was applied for blood serum sample. The biosensor was made from Screen Printed Carbon Electrode (SPCE) which coated nata de coco immobilized urease. Accordingly, various pH (6; 7; 8; 9), urease mass (0.1; 0.5; 1,0; 1.5 µg), and membran thickness (5; 10; 15 µm) was studied in detail with range concentrations of urea solution were 0 to 5 ppm in phophate buffer 0.01 M pH 8 and SPCE area 5 mm2. The result showed that the optimum performance in 1 µg urease mass, 5 µm membrane thickness, and pH solution was 8, whereas the sensitivity was 14.8 µS/ppm, detection limit was 0.035 ppm, and range concentrations of urea were 0.035 to 0.400 ppm. The biosensor have 73 to 87 % accuration.when be applied in blood serum sample.