Project's information
| Project's title | Study on the fabrication of electrochemical sensors modified by organic-inorganic composite materials – metal nanostructures for the analysis of some antibiotics in the environment |
| Project’s code | VAST07.02/22-23 |
| Research hosting institution | Institute of Chemistry |
| Project leader’s name | Dr. Pham Thi Hai Yen |
| Project duration | 01/01/2022 - 31/12/2023 |
| Project’s budget | 600 million VND |
| Classify | Grade A |
| Goal and objectives of the project | The main objective of the project is to synthesize and modify electrode materials to create electrochemical sensors, aiming to enhance the capability of detecting and quantifying certain antibiotics in surface water environments through electrochemical methods. |
| Main results | Theoretical results:
- Successfully fabricated polyglutamic acid/graphite using a two-step electrochemical potential method.The electrode exhibits excellent electrochemical activity with a 1.5 times larger active surface area than the unmodified electrode. It shows an enhancement in the enrofloxacin (ENR) signal (13.5 times) compared to the unmodified electrode. Demonstrates good repeatability (Relative Standard Deviation, RSD = 4.3%) and a linear analysis range of 0.1 – 5 µM. Achieves a low detection limit (LOD) of 0.122 µM and high recovery in standard sample analysis (97.5%).
- Screening of MOFs, including FeBTC and CuBTC, significantly increased ENR oxidation signals on modified electrodes. The highest signal was obtained with CuBTC-modified electrodes.
- Electrode Modification with CuBTC MOF 10% w/w (CuBTC@CPE): Displays good electrochemical activity with enhanced ENR signal (7.7 times) compared to the unmodified electrode. Shows good repeatability (RSD = 4.5%), a linear analysis range of 0.01 µM – 12 µM, and a low LOD of 0.009 µM. Exhibits good selectivity and good recovery in different water and milk samples (96.5-105%). Demonstrates good durability over 30 days.
- Successfully fabricated electrodes modified with multi-layered nano graphite (G-DMSO) and nano carbon tubes (rCNT/GCE): Exhibit excellent charge transfer ability, a larger electrochemical active surface, and high sensitivity to enrofloxacin (ENR) with a low detection limit (LOD) of 0.002 µM. Successfully applied for the analysis of ENR in tap water (G-DMSO electrode) and shrimp samples (rCNT/GCE electrode) with good recoveries (105.5% and 96.3%).
- Successfully synthesized the CuBTC-CNT@CPE electrode. The synergistic effects of carbon nanotubes and CuBTC significantly increased the ENR signal by 12.5 times. The electrodes demonstrate excellent sensitivity (LOD = 0.003 µM), three times better than CuBTC@CPE, and comparable to nanocarbon electrodes with a shorter enrichment time. Shows good repeatability (RSD = 4.42%), high selectivity, good durability over 38 days.
- Investigated the electrochemical oxidation reaction mechanism of enrofloxacin (ENR) on the fabricated electrodes.
Applied results:
The developed electrodes have been successfully tested for the analysis of the antibiotic enrofloxacin (ENR) in various real samples, including tap water, West Lake water, seawater, milk, shrimp, and synthetic urine samples. These results demonstrate the high applicability of the project's outcomes in assessing the contamination levels of the antibiotic ENR in environmental samples, certain food products. The electrodes are suitable for deployment in analytical applications both in laboratory and in the field. |
| Novelty and actuality and scientific meaningfulness of the results | Developed electrodes modified with various materials, including polyglutamic acid, rCNT, multi-layered nano graphite, CuBTC, and CuBTC-CNT, have been successfully developed. These modified electrodes have been effectively applied for the analysis of the antibiotic enrofloxacin in diverse sample matrices. Their sensitivity is notably lower compared to many types of electrochemical electrodes that have been researched and published worldwide. |
| Products of the project | Scientific papers in referred journals (list):
- Electrochemical Determination of Enrofloxacin Using an Electrode Composed of Graphite Nanosheets Fabricated by Expansion in Dimethyl Sulfoxide. Thi Nhat Quyen Do, Thi Thu Ha Vu, Quoc Hung Le, Thi Phuong Nam Pham, Thi Thao Ta, Thi Lieu Nguyen & Thi Hai Yen Pham*. Analytical Letters, DOI: 10.1080/00032719.2023.2284222 (SCIE, Q3, IF 2.267)
- Fabrication and application of functionalized carbon nanotubes for highly sensitive and selective sensing of Enrofloxacin. Tien Dat Doan, Yen Thi Hai Pham*, Hac Thi Nhung, Ho Thi Oanh, Tuyen Nguyen Duc, Hung Quoc Le, Thu Ha Thi Vu, Phong Hong Pham, Mai Ha Hoang*. Vietnam J. Chem. 2024;62:76–85 (VAST 1, Scopus, Q3).
Technological products (describe in details: technical characteristics, place):
- Three electrodes modified with conducting polymer with LOD of 0.122 µM for ENR, an accuracy higher than 95% (recovery = 96.0%).
- Three electrodes modified with metal-organic framework material with LOD of 0.009 µM for ENR, an accuracy higher than 95% (recovery of 96.5-103.0% in water samples).
- Three electrodes modified with composite material with LOD of 0.003 µM for ENR, an accuracy higher than 95% (recovery of 98.5-101.5%).
- Three electrodes modified with multi-layered nano graphite with LOD of 0.002 µM for ENR, an accuracy of approximately 95% (recovery of 105.5%).
- Three electrodes modified with functionalized nano carbon tubes LOD of 0.003 µM for ENR, with an accuracy higher than 95% (recovery rate of 96.3%).
These electrodes are stored at the Institute of Chemistry.
Other products (if applicable): Training 02 doctoral students. |
| Recommendations | Request to facilitate the continued development of the following research directions: combining MOF with functionalized CNT and with G-DMSO; experimenting with simultaneous analysis of multiple antibiotics; improving the repeatability of electrodes or studying the optimization of electrode cleaning processes, thereby developing sensors capable of on-site analysis. |
| Images of project |
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