Search for: aptamer
Predicting the cardiac troponin I (cTnI) aptamer/methylene blue configuration using computational modeling studies: a screening search method for constructing aptasensors, Article ChemistrySelect ; Volume 5, Issue 35 , September , 2020 , Pages 10958-10969 ; Khajehsharifi, H ; Hashemnia, S ; Shahrokhian, S ; Sharif University of Technology
Acute Myocardial Infarction (AMI) is the most common cause of mortality, and cardiac troponin I (cTnI) is the gold standard for AMI diagnosis. Some aptamers have been reported to detect cTnI, but there is rarely any structural information on their binding with cTnI. There are many studies involving electrochemical aptasensors with methylene blue (MB) as a redox indicator that does not provide any significant new information. Our study, however, involves the computational modeling of the complexes of a documented 40-mer ssDNA-cTnI aptamer with its target and MB. Here, MB was used as a model system to investigate the rather complex interaction modes between small redox molecules and a...
Article BioMed Research International ; Volume 2021 , 2021 ; 23146133 (ISSN) ; Moosavi, A ; Alexandrakis, G ; Mofrad, M. R. K ; Sharif University of Technology
Hindawi Limited 2021
Interest in the design and manufacture of RNA and DNA aptamers as apta-biosensors for the early diagnosis of blood infections and other inflammatory conditions has increased considerably in recent years. The practical utility of these aptamers depends on the detailed knowledge about the putative interactions with their target proteins. Therefore, understanding the aptamer-protein interactions at the atomic scale can offer significant insights into the optimal apta-biosensor design. In this study, we consider one RNA and one DNA aptamer that were previously used as apta-biosensors for detecting the infection biomarker protein TNF-α, as an example of a novel computational workflow for...
Specific targeting delivery to MUC1 overexpressing tumors by albumin-chitosan nanoparticles conjugated to DNA aptamer, Article International Journal of Pharmaceutics ; Volume 515, Issue 1-2 , 2016 , Pages 607-615 ; 03785173 (ISSN) ; Mohammadi, A ; Atyabi, F ; Nabavi, S. M ; Ebrahimi, S. M ; Shahmoradi, E ; Shiri Varnamkhasti, B ; Ghahremani, M. H ; Dinarvand, R ; Sharif University of Technology
Elsevier B.V 2016
Chitosan-coated human serum albumin nanoparticles were functionalized by MUC1 aptamer to obtain a selective drug carrier toward cancers overexpressing MUC1. The negative charges of albumin nanoparticles were shifted to positive charges by surface modification with chitosan, and MUC1 was conjugated through an acrylate spacer. The cytotoxicity of targeted nanoparticles was significantly more than non-aptamer nanoparticles, and also the chitosan-coated nanoparticles had more cytotoxic effects than the negatively charged albumin nanoparticles. The IC50 of targeted nanoparticles was 28 and 26% of free paclitaxel in MCF7 and T47D cells at 48 h, respectively. Confocal laser scanning electron...
M.Sc. Thesis Sharif University of Technology ; Vosoughi, Manouchehr ; Alemzadeh, Iran
Cancer is a major cause of mortality worldwide, with a disease burden estimated to grow over the coming decades. Circulating tumor cells (CTCs) are rare cancer cells released from the primary or metastatic tumors and transported though the peripheral circulatory system to their specific secondary locations. The presence of CTCs in a cancer patient’s blood has been used as a prognostic biomarker, with lower CTC count correlating with greater overall survival. In spite of its clinical potential, the isolation and detection of CTCs has been a challenging task due to its rare presence amongst other blood cells (as low as 1–10 CTCs per billions of blood cells) and variability in terms of both...
M.Sc. Thesis Sharif University of Technology ; Shamloo, Amir ; Hosseini, Vahid
Due to the urgent need for early diagnosis of many blood and gastrointestinal diseases, the development and optimization of rapid diagnosis kits is considered important. One of the best ways to make these kits is to use paper microfluidics. The paper platform is inexpensive and compatible with diagnostic processes and can enable rapid and high-sensitivity detection. In the present study, filter paper has been used as the main platform and hydrophobic channels have been created with the help of a hydrophobic marker to guide the fluid on the paper substrate. To perform the detection process, color changes resulting from the aggregation of nanoparticles on the paper are used. In this case, in...
Enhancement mitochondrial apoptosis in breast cancer cells by paclitaxel-triphenylphosphonium conjugate in DNA aptamer modified nanoparticles, Article Journal of Drug Delivery Science and Technology ; Volume 54 , 2019 ; 17732247 (ISSN) ; Mohammadi, A ; Atyabi, F ; Ebrahimi, S. M ; Shahmoradi, E ; Amini, M ; Mirzaie, Z. H ; Ghahremani, M. H ; Dinarvand, R ; Sharif University of Technology
Editions de Sante 2019
Mitochondria is a major regulator of inducing tumor apoptosis and it is as a prime target for chemotherapy. Anticancers need to access specific tumor cells and also pass through different barriers such as outer and inner membranes of mitochondria. Targeted accumulation of paclitaxel (PTX) within the mitochondria was achieved by direct conjugation of PTX with triphenylphosphonium (TPP) as a mitochondrial membrane-permeable cation. PTX-TPP prodrug was synthesized by pH-sensitive ester bond between the hydroxyl function of PTX and the carboxylic function of TPP. This ester bond is only cleaved by the mitochondrial aldehyde dehydrogenase. Prodrug was loaded in the albumin nanoparticles by...
Design, Construction and Application of Nanostructured Electrochemical Biosensor Based on Aptamers for Diagnosis Some of the Pathogenic Bacteria, Ph.D. Dissertation Sharif University of Technology ; Shahrokhian, Saeed
Since that pathogenic bacteria have a predominant role in different aspects of human life such as clinical analysis and spread of contagious disease, food quality control and monitoring of environmental microbial infections, the aim of these studies is design and construction of electrochemical and electro-optical biosensors based on nanomaterials employing specific aptamer and antibody for detection of different bacteria in various real samples. An impedimetric biosensor based on nanoporous gold (NPG) was presented in the first part of the thesis for detection of Salmonella typhimurium as one of the main food- borne pathogenic bacterium. Three-dimensional structure of NPG was synthesized...
Specific picomolar detection of a breast cancer biomarker her-2/neu protein in serum: electrocatalytically amplified electroanalysis by the aptamer/peg-modified electrode, Article ChemElectroChem ; Volume 4, Issue 4 , 2017 , Pages 872-879 ; 21960216 (ISSN) ; Kékedy Nagy, L ; Ferapontova, E. E ; Sharif University of Technology
Wiley-VCH Verlag 2017
Specific and sensitive electroanalysis of blood-circulating protein cancer biomarkers is often complicated by interference from serum proteins nonspecifically adsorbing at the biosensing interface and masking specific reactions of interest. Here, we have developed an electrocatalytically amplified assay for specific and sensitive analysis of human epidermal growth factor receptor-2 (HER-2/neu, a protein cancer biomarker over-expressed in breast cancers) that allows us to avoid both the interference from bovine serum albumin (BSA) and electrocatalytic amplification of the signal stemming from the specific aptamer−HER-2/neu binding. A HER-2/neu-specific thiolated aptamer sequence was...
Recent advancements in aptamer-bioconjugates: Sharpening stones for breast and prostate cancers targeting, Article Journal of Drug Delivery Science and Technology ; Volume 53 , 2019 ; 17732247 (ISSN) ; Shahraki, B. T ; Rabiee, N ; Afshari, R ; Fatahi, Y ; Dinarvand, R ; Ahmadi, S ; Bagherzadeh, M ; Rabiee, M ; Tahriri, M ; Tayebi, L ; Sharif University of Technology
Editions de Sante 2019
Breast and prostate cancers are common types of cancers with various strategies, such as chemotherapy and radiotherapy, for their therapy. Since these methods have undesired side effects and poor target affinity, neoteric strategies—known as aptamer-based smart drug delivery systems (SDDSs)—have been developed in recent years to overcome the obstacles of current treatment, and investigated for a clinical trial. The high affinity and versatility of aptamers for binding to the corresponding targets make them highly noticeable agents in the drug delivery domains. In addition to their exceptional benefits, aptamers are able to overcome tumor resistance because of their high selectivity and low...
Aptamer hybrid nanocomplexes as targeting components for antibiotic/gene delivery systems and diagnostics: a review, Article International Journal of Nanomedicine ; Volume 15 , 2020 , Pages 4237-4256 ; Arab, Z ; Safarkhani, M ; Nasseri, B ; Rabiee, M ; Tahriri, M ; Webster, T. J ; Tayebi, L ; Rabiee, N ; Sharif University of Technology
Dove Medical Press Ltd 2020
With the passage of time and more advanced societies, there is a greater emergence and incidence of disease and necessity for improved treatments. In this respect, nowadays, aptamers, with their better efficiency at diagnosing and treating diseases than antibodies, are at the center of attention. Here, in this review, we first investigate aptamer function in various fields (such as the detection and remedy of pathogens, modification of nanoparticles, antibiotic delivery and gene delivery). Then, we present aptamer-conjugated nanocomplexes as the main and efficient factor in gene delivery. Finally, we focus on the targeted co-delivery of genes and drugs by nanocomplexes, as a new exciting...
Evaluation of molecular imprinted polymerized methylene blue/aptamer as a novel hybrid receptor for cardiac troponin I (cTnI) detection at glassy carbon electrodes modified with new biosynthesized ZnONPs, Article Sensors and Actuators, B: Chemical ; Volume 320 , 1 October , 2020 ; Khajehsharifi, H ; Hashemnia, S ; Solati, Z ; Azimpanah, R ; Shahrokhian, S ; Sharif University of Technology
Elsevier B.V 2020
In this research, a novel, rapid, and non-immune electrochemical method was used to detect cardiac troponin I (cTnI) using a double recognition approach. Amine terminus cTnI aptamers immobilized on COOH-ZnO nanoparticles (COOH-ZnONPs) modified GCE surface were applied to capture cTnI for imprinting recognition. The COOH-ZnONPs were synthesized in a biological manner. Then, the methylene blue (MB) monomers were electro-polymerized around the cTnI-aptamer complexes. Following the removal of cTnI, cavities were constructed and converted to a new aptamer and molecular imprinted polymer (MIP) hybrid receptor (aptamer/MIP/ZnONPs). FT-IR spectra, SEM images, XRD patterns, and electrochemical...
Personalised deposition maps for micro- and nanoparticles targeting an atherosclerotic plaque: attributions to the receptor-mediated adsorption on the inflamed endothelial cells, Article Biomechanics and Modeling in Mechanobiology ; Volume 18, Issue 3 , 2019 , Pages 813-828 ; 16177959 (ISSN) ; Forouzandehmehr, M ; Sharif University of Technology
Springer Verlag 2019
Endothelial inflammation as a prominent precursor to atherosclerosis elicits a distinct pathological surface expression of particular vascular proteins. To exhibit a site-specific behaviour, micro- and nanoparticles, as carriers of therapeutics or imaging agents, can distinguish and use these proteins as targeted docking sites. Here, a computational patient-specific model capturing the exclusive luminal qualities has been developed to study the transport and adsorption of particles decorated with proper antibodies over an atherosclerotic plaque located in the LAD artery of the patient. Particles, in nano- and micron sizes, have been decorated with Sialyl Lewisx (sLex), P-selectin aptamer...
Design and fabrication of an electrochemical aptasensor using Au nanoparticles/carbon nanoparticles/cellulose nanofibers nanocomposite for rapid and sensitive detection of Staphylococcus aureus, Article Bioelectrochemistry ; Volume 123 , 2018 , Pages 70-76 ; 15675394 (ISSN) ; Shahrokhian, S ; Sharif University of Technology
Elsevier B.V 2018
Since that pathogenic bacteria are major threats to human health, this paper describes the fabrication of an effective and durable sensing platform based on gold nanoparticles/carbon nanoparticles/cellulose nanofibers nanocomposite (AuNPs/CNPs/CNFs) at the surface of glassy carbon electrode for sensitive and selective detection of Staphylococcus aureus (S. aureus). The AuNPs/CNPs/CNFs nanocomposite with the high surface area, excellent conductivity, and good biocompatibility was used for self-assembled of the thiolated specific S. aureus aptamer as a sensing element. The surface morphology of AuNPs/CNPs/CNFs nanocomposite was characterized with field emission scanning electron microscopy...