5 research outputs found
Multilayered Mesoporous Composite Nanostructures for Highly Sensitive Label-Free Quantification of Cardiac Troponin-I
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@ZIF-67-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
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Anti-inflammatory effects of eugenol nanoemulsion as a topical delivery system
Eugenol is the main constituent of clove oil with anti-inflammatory properties. In this work, for the first time, O/W nanoemulsion of eugenol was designed for the evaluation of anti-inflammatory effects as a topical delivery system. Topical formulations containing 1%, 2% and 4% of eugenol as well as a nanoemulsion system containing 4% eugenol and 0.5% piroxicam were prepared. Further to physicochemical examinations, such as determination of particle size, polydispersity index, zeta potential and physical stability, anti-inflammatory activity was examined in carrageenan-induced paw edema in rats. The optimum formulation was found to contain 2% eugenol (oil phase), 14% Tween 20 (surfactant) and 14% isopropyl alcohol (co-surfactant) in water. Nanoemulsion with polydispersity index of 0.3 and median droplet diameter of 24.4 nm (d50) was obtained. Animal studies revealed that the nanoemulsions exhibited significantly improved anti-inflammatory activity after 1.5 h, compared with marketed piroxicam gel. Additionally, it was shown that increasing the concentration of eugenol did not show higher inhibition of inflammation. Also, the nanoemulsion having piroxicam showed less anti-inflammatory properties compared with the nanoemulsion without piroxicam