Fast analysis method of aspartame from foods using an amperometric enzymatic biosensor







Project number: PN-III-P2-2.1-PED-2016-0503; Contract no. PED- 180/2017


Project Director: Ph.D Petruta-Madalina BUCUR;


Project category: PED;


Project budget: 475.000

Contract period: 17 months (17.08.2017- –31.12.2018);


Contracting Authority: Executive Unit for Higher Education, Research, Development and Innovation Funding- (UEFISCDI);


Contractant: National Institute of Research and Development for Biological Sciences;

Contract number: PED180/2017;

 Contact: Madalina Bucur









     Project Manager: CS II Dr. Petruta Madalina BUCUR


Dr. Petruta Madalina BUCUR (ResearcherID: B-9624-2011) has obtained his Ph.D. in 2007 at University of Bucharest with thesis entitled: “Chemical and biochemical sensors for analytical control of some pollutants in environmental sample”. Her research interest covers different domains of analytical chemistry and biochemistry such as: enzymatic biosensors, electrochemical sensors, flow injection analysis methods, piezoelectric analysis, enzymatic biosensor development for substrate or inhibitor detection, different methods for enzyme immobilization and stabilization, use of electrochemical mediators. She is author of 15 original papers in peer-reviewed journals and 3 Romanian patents. She was director/responsible of 3 national project: PN-II-RU-TE-0076/2011 and SAFEFOOD, project no. 61030/2007, PN-II-PT-PCCA-2013-4-0297, SENSWINE). She has been researcher in 3 European contracts and has extensive experience in national grants (more then 10 projects).




Faculty of Electronics, Telecommunications and Information Technology

     Responsible P2: Conf. Dr. ing. Ion RUSU


Dr. eng.  Ion Rusu, conf eng, University POLITEHNICA of BUCHAREST, Faculty of Electronic, Telecommunication and Information Technology- has obtained his Ph.D. in 2001 at University Politehnica of Bucharest, project: “Microwave Circuits and Devices for hyperthermia therapy". His research interest: Electronic devices and microwave circuits, for medical  therapies. He is co-author of 31 original papers in conference proceedings or journals and 2 Romanian patent. He has been researcher in over 38 national and international projects/grants and has extensive experience in national grants (director/scientific responsible for 18 research grants). He is co-author of 2 original book, "Biological effects of radiation RF and Microwave" and “Absorption of electromagnetic field and human head area ".






Public budget (lei)





TOTAL (lei)






         This demonstrative project aims to develop and validate in laboratory a fast analytical method for detection of aspartame from food samples based on a combination of an amperometric enzymatic biosensor and a Low-noise potentiostat. The growing use of aspartame in the food industry requires the development of rapid and effective methods for its determination. The project aims to provide a cost effective and easy to use analytical method of aspartame.  The detection principle of the biosensor is based on enzymatic oxidation of aspartame catalyzed by carboxyl esterase (CaE) and alcohol oxidize (AOX), with the production of hydrogen peroxide that is electrochemically quantified. The developed potentiostat used for the quantification of the biosensors’ amperometric signals has two building blocks: (i) a potentiostat circuit that provides constant continuous voltage and (ii) current sensing circuit to quantify the current solution ICELL related with the concentration of aspartame. Low-pass filter will be added to the current sensing circuit’s feedback loop to diminish the induced electromagnetic noise effects. The consortium combines the vast experience in the field of biosensors and enzymology of National Institute of R&D for Biological Sciences with the know-how in electronic potentiostat design of the University Politehnica of Bucharest.




Ø  Preliminary studies for aspartame biosensor development (31 December 2017);

Ø  Development of analytical methods for the fast and selective quantification of aspartame. Method validation by comparison with alternative technique (31 December 2018)






Phase 1/2017


         In this phase the  experiments were carried out to modify electrodes with a stable Prussian blue layer containing copper ions for stabilization. It was studied the operational parameters of the biosensor based on the amperometric quantification of hydrogen peroxide which has a direct proportional concentration with the analytes. Studies have also been carried out to develop a complex potentiostat that has a good stability at low currents and reduction of the ambient noises using an integrated filter.






Fig. 1. Cyclic voltammograms  for modified electrodes with PB       


Fig 2. The calibration plots obtained for methanol using a biosensor with alcohol oxidase













   Fig. 3. The general scheme for sensor.



Fig.4 Frequences characteristic of  instrumentation amplifier with  FTJ filter

Fig.5 Noise characteristic of instrumentation amplifier with FTJ filter


Phase 2/2018

Development of analytical methods for the fast and selective quantification of aspartame.


In this phase it was developed a fast analytical method for detection of aspartame from food samples based on a combination of an amperometric enzymatic biosensor and a Low-noise potentiostat. The biosensors were produced by co-immobilisation of carboxylesterase and alcohol oxidase on carbon paper electrodes electromodified with a Prussian blue-copper mixt mediator layer. The low nois- potentiostat developed in the project has very good stability and is powered by a 5 V accumulator. The results obtained with the biosensors were compared with a HPLC method.



Fig.1. The potentiostat developed in the project


Fig.2. The calibration plots obtained with the bienzymatic biosensor and recorded with the develloped potentiostat






A. Articles:


1. E. Rusen, A. Diacon, A. Mocanu, F. Rizea,  B.  Bucur,  M.  P. Bucur,  G.-L. Radu, E. Bacalum, M.  Cheregi, V. David, RSC Advances, 7, 2017, 50844-50852, IF=3.108

2. P.M. Bucur, B. Bucur,G. L. Radu, RSC Advances, 8, 2018, 23931-23936, I.F. 2,94


B. Conferences:

 1. C. M. Radulescu, P.M. Bucur, B. Bucur, G.L. Radu, Carbon Fiber Composite Paper Electrodes Modified with Stable Prussian Blue-Copper Used for Bienzymatic Determination of Sweeteners in Food, ElecNano8, Electrochemistry for Nano & Nano for Electrochemistry, Nancy, Franta 2018.

2. G. Pristavu, G. Brezeanu, R. Pascu, M. Badila, F.Draghici, I. Rusu,  Series Resistance Effect on Inhomogeneous SiC-Schottky Diode Forward Characteristics – An Ideal Interpretation, European European Conference on Silicon Carbide and Related Materials (ECSCRM 2018), Birmingham, UK, 2018.

3. M.C. Radulescu P.M. Bucur, B. Bucur,G. L. Radu, Flavors detection in foods with a bi-enzymatic biosensor based on a stable pb-cu film/ carbon paper electrode, PRIOCHEM XIV,2018, Bucuresti,

4. P.M. Bucur, B. Bucur,G. L. Radu Immobilization of Cholinesterase in Sol-Gel Protective Microporous Matrix for Insecticide Detection in OrganicSolvents Mixtures, Electrochemistry for Nano & Nano for Electrochemistry, Nancy, Franta 2018.


C. Patent:

A/00945/26.11.2018, Modalitate de reducere a perturbatiilor electromagnetice parazite in sistemul de masura de tip potentiostat cu senzori bioelectrochimici


Update:December 2018