Publications by authors named "Asamee Soleh"

2 Publications

  • Page 1 of 1

Discrimination of dopamine by an electrode modified with negatively charged manganese dioxide nanoparticles decorated on a poly(3,4 ethylenedioxythiophene)/reduced graphene oxide composite.

J Colloid Interface Sci 2021 Mar 31;597:314-324. Epub 2021 Mar 31.

Center of Excellence for Trace Analysis and Biosensor, Prince of Songkla University, Hat Yai, Songkhla 90112, Thailand; Center of Excellence for Innovation in Chemistry, Faculty of Science, Prince of Songkla University, HatYai, Songkhla 90112, Thailand; Division of Health and Applied Sciences, Faculty of Science, Prince of Songkla University, Hat Yai, Songkhla 90112, Thailand. Electronic address:

A unique nanocomposite was fabricated using negatively charged manganese dioxide nanoparticles, poly (3,4-ethylenedioxythiophene) and reduced graphene oxide (MnO/PEDOT/rGO). The nanocomposite was deposited on a glassy carbon electrode (GCE) functionalized with amino groups. The modified GCE was used to electrochemically detect dopamine (DA). The surface morphology, charge effect and electrochemical behaviours of the modified GCE were characterized by scanning electron microscopy, energy dispersive X-ray analysis (EDX), cyclic voltammetry and electrochemical impedance spectroscopy, respectively. The MnO/PEDOT/rGO/GCE exhibited excellent performance towards DA sensing with a linear range between 0.05 and 135 µM with a lowest detection limit of 30 nM (S/N = 3). Selectivity towards DA was high in the presence of high concentrations of the typical interferences ascorbic acid and uric acid. The stability and reproducibility of the electrode were good. The sensor accurately determined DA in human serum. The synergic effect of the multiple components of the fabricated nanocomposite were critical to the good DA sensing performance. rGO provided a conductive backbone, PEDOT directed the uniform growth of MnO and adsorbed DA via pi-pi and electrostatic interaction, while the negatively charged MnO provided adsorption and catalytic sites for protonated DA. This work produced a promising biosensor that sensitively and selectively detected DA.
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http://dx.doi.org/10.1016/j.jcis.2021.03.162DOI Listing
March 2021

A portable electrochemical sensor for detection of the veterinary drug xylazine in beverage samples.

J Pharm Biomed Anal 2021 May 8;198:113958. Epub 2021 Feb 8.

Center of Excellence for Trace Analysis and Biosensors (TAB-CoE), Prince of Songkla University, Hat Yai, Songkhla, 90112, Thailand; Center of Excellence for Innovation in Chemistry, Faculty of Science, Prince of Songkla University, Hat Yai, Songkhla, 90112, Thailand; Division of Health and Applied Sciences, Faculty of Science, Prince of Songkla University, Hat Yai, Songkhla, 90112, Thailand. Electronic address:

A portable electrochemical sensor was developed to determine xylazine in spiked beverages by adsorptive stripping voltammetry (AdSV). The sensor was based on a graphene nanoplatelets-modified screen-printed carbon electrode (GNPs/SPCE). The electrochemical behavior of xylazine at the GNPs/SPCE was an adsorption-controlled irreversible oxidation reaction. The loading of graphene nanoplatelets (GNPs) on the modified SPCE, electrolyte pH, and AdSV accumulation potential and time were optimized. Under optimal conditions, the GNPs/SPCE provided high sensitivity, linear ranges of 0.4-6.0 mg L (r = 0.997) and 6.0-80.0 mg L (r = 0.998) with a detection limit of 0.1 mg L and a quantitation limit of 0.4 mg L. Repeatability was good. The accuracy of the proposed sensor was investigated by spiking six beverage samples at 1.0, 5.0, and 10.0 mg L. The recoveries from this method ranged from 80.8 ± 0.2-108.1 ± 0.3 %, indicating the good accuracy of the developed sensor. This portable electrochemical sensor can be used to screen for xylazine in beverage samples as evidence in cases of sexual assault or robbery.
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http://dx.doi.org/10.1016/j.jpba.2021.113958DOI Listing
May 2021