RESUMO
Food allergies have become a global issue and are estimated to affect approximately 220 million people worldwide. Allergy to peanuts can easily become life-threatening and induce anaphylactic reactions. Mislabeling and cross-contamination during food processing can occur in the frame of world population growth and pose a serious health issue. As the mandatory allergen list is not uniform worldwide, the development of routine analytical strategies with high specificity and sensitivity is a demanding task to aid in the rapid identification of allergenic foods. In this work, an electrochemical aptasensor for Ara h1 peanut allergen was developed by immobilizing the specific aptamer by the inserting method. First, a layer of p-aminothiophenol (p-ATP) was immobilized on the gold surface of screen-printed electrodes (GSPE) to improve the aptamer insertion and reduce the fouling effects at the electrode surface. The grafting of the p-ATP and Ara h1 aptamer on the GSPE surface was monitored by cyclic voltammetry (CV), differential pulse voltammetry (DPV), and electrochemical impedance spectroscopy (EIS). The resulting disposable aptasensor allowed for indirect electrochemical detection of Ara h1 protein in the presence of 5 mM ferro/ferricyanide as a redox probe. The electrochemical response upon aptamer-target interaction was monitored in the concentration range 1-250 nM, and two limits of detection in the nanomolar range were estimated based on DPV (2.78 nM Ara h1) and EIS (0.82 nM Ara h1) measurements. The aptasensor was successfully applied to real sample analysis.
Assuntos
Compostos de Anilina , Incrustação Biológica , Hipersensibilidade Alimentar , Compostos de Sulfidrila , Humanos , DNA , Oligonucleotídeos , Arachis , Ouro , Alérgenos , Trifosfato de AdenosinaAssuntos
Cromossomos Humanos Par 12 , Cromossomos Humanos Par 5 , Transtornos Mieloproliferativos/tratamento farmacológico , Transtornos Mieloproliferativos/genética , Translocação Genética , Benzamidas , Doença Crônica , Eosinofilia/diagnóstico , Humanos , Mesilato de Imatinib , Masculino , Pessoa de Meia-Idade , Piperazinas/uso terapêutico , Pirimidinas/uso terapêuticoRESUMO
Using flow cytometry, we investigated the clinical and hematologic relevance of expression of heat-shock proteins (HSP) HSP27, HSP60, HSP70, HSP90 and HSP110 in bone marrow of 142 patients with newly diagnosed myelodysplastic syndromes, together with that of the membrane differentiation antigen CD34 and the drug-resistance related protein, P170 (Pgp).