Amperometric bi-enzyme based biosensor for the determination of lactose with an extended linear range

Çelik

J of Applied Polymer Sci

2013

Lactose biosensor based on surfactant doped polypyrrole (PPy) was developed. Galactose oxidase and β‐galactosidase was coimmobilized in PPy matrix during electropolymerization process with the presence of sodium dodecylbenzene sulphonic acid as surfactant. Bi‐enzyme entrapped PPy was characterized with Fourier transform infrared spectroscopy (FTIR), cyclic voltammetry (CV), and scanning electron microscopy (SEM). The response of the enzyme electrode was measured by CV in the range of −0.1 to 1.0 V versus Ag/AgCl which was due to the electrooxidation of enzymatically produced H2O2. The effect of lactose concentration was investigated. Response time of biosensor was found to be 8–10 s (the time required to obtain the maximum peak current) and upper limit of the linear working portions was found to be 1.22 mM lactose concentration with a detection limit of (2.6 × 10−6 M). The apparent Michaelis–Menten constant was found to be 0.117 mM lactose. The effects of interferents (ascorbic acid and uric acid) were determined. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40200.

Section: Introductionmentioning

confidence: 99%

“…Biosensors offer a cheap, quick, and reliable alternative for the determination of lactose. Several types of lactose biosensors have been reported in literature …”

Section: Introductionmentioning

confidence: 99%

Electrochemical Biosensor Based on surfactant doped polypyrrole (PPy) matrix for lactose determination

Çelik

J of Applied Polymer Sci

2013

Analytical and Bioanalytical Chemistry

“…The optimized procedure of PCS preparation has been described earlier [54,55]. PCS solution were prepared by dissolving 150 mg PCS prepolymer in 400 µL water.…”

Section: Sensor Preparationmentioning

confidence: 99%

Biosensors and flow-through system for the determination of creatinine in hemodialysate

Erlenkötter

Fobker

Chemnitius

2002

Self Cite

Biosensors for the determination of creatinine have been developed and integrated into a flow-through system. The sensors are based on a screen-printed three electrode transducer with a platinum working electrode. Applying the multi-enzyme sequence of creatininase (CA), creatinase (CI) and sarcosine oxidase (SO) hydrogen peroxide has been detected amperometrically. An optimal enzyme load was found to be 4.4 U/0.28 U/0.20 U (CA/CI/SO) and 0.28 U/0.20 U (CI/SO) per electrode for the creatinine sensor and for the creatine sensor, respectively. Among a variety of polymers Nafion has shown the highest efficiency to exclude interfering substances like ascorbic acid, acetaminophen and uric acid. First determinations of creatinine in dialysate samples obtained during hemodialysis treatments have shown a good correlation to the conventional methods, the Jaffé reaction (y=0.945x+ 2.8, R=0.9882, n=9) and the enzymatic photometric method (y=0.891x+3.5, R=0.9917, n=9).

“…Studies on the enzymatic determination of sucrose on the basis of amperometric electrodes were performed in our group as well as in others [3,4]. Besides that, lactose electrodes were also prepared for food analysis up to 2-5 mm lactose concentration [5,6].…”

Section: Introductionmentioning

confidence: 96%

Measurement of glucose, sucrose and lactose in food samples with enzyme-immobilised packed-bed column reactors integrated to an amperometric enzyme electrode

Boyaci

Mutlu

2002

Nahrung

An amperometric enzyme electrode integrated with packed-bed column reactors containing immobilised enzymes was improved to measure glucose, sucrose and lactose content of food samples with only one sampling. Performance parameters of the system were investigated on the bases of linearity, sensitivity and response time. Those values were found to be 20 mM, 24.9 nA/mM and 20 s for glucose; 20 mM, 12.0 nA/mM and 3 min for sucrose; 12 mM, 10.8 nA/mM and 4 min for lactose, respectively. Overall analysis time for three analytes with one sampling was less than 8 min without pretreatment and interference of electroactive compounds and substrates. Glucose, sucrose and lactose content of the model and food samples were measured with both the improved system and commercial enzyme kits. There was high correlation between the results. This gives us the opportunity to use the improved electrode system for determination of glucose, sucrose and lactose in food samples. Also this result was found to be very promising in extending the spectrum of detectable analytes simply by addition of new columns containing immobilised enzymes that are specific to target analytes.