Yazar "Saeidi, Mohsen" seçeneğine göre listele

Listeleniyor 1 - 3 / 3
  • Küçük Resim Yok
    Öğe
    Efficient electrochemical CO2 conversion by cobalt-based metal organic frameworks modified by bimetallic gold-silver nanostructures
    (Royal Soc Chemistry, 2023) Beheshti, Mohammadali; Saeidi, Mohsen; Adel-Rastkhiz, MahsaSadat; Shahrestani, Shohreh; Zarrabi, Ali; Bai, Jing; Simchi, Abdolreza
    The ongoing and rapid growth of atmospheric CO2 levels causes a crucial worldwide concern. Herein, an efficient electrocatalyst has been introduced for electrochemical CO2 reduction reaction (CO2RR) to address the stability issue of ZIF-67. The catalyst consists of gold and silver nanostructures electrodeposited on the surface of a cobalt-based metal-organic framework (Au-Ag@ZIF-67). The uniform distribution of the Au-Ag alloy without any agglomeration on ZIF-67 was confirmed through microscopic observations. After 13.3 h of CO2RR, the specific surface area of Au-Ag@ZIF-67 slightly decreased, whereas that of ZIF-67 declined drastically, indicating excellent structural stability of the Au-Ag alloy. Additionally, Au-Ag@ZIF-67/GCE revealed a faradaic efficiency of 53% and 38% for CO and H-2, respectively. The enhanced CO2 absorption coupled with the effect of noble metal catalysts offered a current density of 16.4 mA cm(-2) at -1 V (vs. RHE) with 91% Faradaic efficiency. The results indicate that ZIF-67 enhanced the adsorption capacity of CO2 molecules in comparison with the bare GCE. The combination of ZIF-67 with bimetallic Au-Ag nanostructures offers enhanced CO2 absorption and reduced charge transfer resistance, leading to improved catalytic activity and selectivity toward CO gas. The results suggest that the use of Au-Ag nanostructures provides superior catalytic activity compared to traditional catalysts, making this approach a promising development for CO2 gas elimination in the environment.
  • Küçük Resim Yok
    Öğe
    Functionalization of metal-organic frameworks with metallic nanoclusters for ultra-sensitive monitoring of morphine in biological fluids
    (Elsevier Science Sa, 2023) Saeidi, Mohsen; Chenani, Hossein; Amidian, Mohammadali; Rajabi, Nooshin; Alimohammadi, Homayoon; Zarrabi, Ali; Simchi, Abdolreza
    A reliable, fast, and cost-effective method of monitoring morphine (MO) concentration in biological fluids is highly desired in clinical and modern medicine. Nanotechnology has opened up new possibilities for developing morphine biosensors, but the most advanced electrodes available offer a detection limit (LOD) of >= 10 nM. This work introduces a new, ultrasensitive electrochemical biosensor based on microporous metal-organic frameworks (-1100 cm2 g-1 surface area) modified by Ag clusters (-2 nm) and functionalized by Au nanoparticles (-180 nm). Electrochemical studies show that functionalizing the microporous crystalline particles (620 +/- 45 nm) with metal nanoclusters enhances charge transfer kinetics and electrochemical surface area by about 50 and 10 folds, respectively, resulting in high sensitivity (0.127 mu A mu M-1), broad linear dynamic range (0.05-600 mu M), and low LOD (3 +/- 0.2 nM). The differential pulse voltammetry confirms the stability (over 6 weeks), repeatability (RSD=3.0%), and reproducibility (RSD=4.0%) of the hybrid biosensor. The decent selectivity and specificity (RSD=7.4%) of the biosensor against various analogs co-existing with MO in urine have also been determined. Therefore, the hybrid metal-inorganic biosensor presents a promising prospect for simple, lowcost, and precise monitoring of biomolecules, including morphine, in biological fluids and clinical medicine.
  • Küçük Resim
    Öğe
    Multilayered mesoporous composite nanostructures for highly sensitive label-free quantification of cardiac troponin-I
    (PMC, 2022) Saeidi, Mohsen; Amidian, Mohammad Ali; Sheybanikashani, Sana; Mahdavi, Hossein; Alimohammadi, Homayoon; Syedmoradi, Leila; Mohandes, Fatemeh; Zarrabi, Ali; Tamjid, Elnaz; Omidfar, Kobra; Simchi, Abdolreza
    Cardiac troponin-I (cTnI) is a well-known biomarker for the diagnosis and control of acute myocardial infarction in clinical practice. To improve the accuracy and reliability of cTnI electrochemical immunosensors, we propose a multilayer nanostructure consisting of Fe3O4 -COOH labeled anti-cTnI monoclonal antibody (Fe3O4 -COOH-Ab1 ) and anti-cTnI polyclonal antibody (Ab2 ) conjugated on Au-Ag nanoparticles (NPs) decorated on a metal–organic framework (Au-Ag@ZIF67-Ab2 ). In this design, Fe3O4 -COOH was used for separation of cTnI in specimens and signal amplification, hierarchical porous ZIF-67 extremely enhanced the specific surface area, and Au-Ag NPs synergically promoted the conductivity and sensitivity. They were additionally employed as an immobilization platform to enhance antibody loading. Electron microscopy images indicated that Ag-Au NPs with an average diameter of 1.9 ± 0.5 nm were uniformly decorated on plate-like ZIF-67 particles (with average size of 690 nm) without any agglomeration. Several electrochemical assays were implemented to precisely evaluate the immunosensor performance. The square wave voltammetry technique exhibited the best performance with a sensitivity of 0.98 mA mL cm?2 ng?1 and a detection limit of 0.047 pg mL?1 in the linear range of 0.04 to 8 ng mL?1 .