Identificação de microcistina LR ao nível molecular empregando microscopia de força atômica

Abstract

Recebido em 21/10/09; aceito em 15/6/10; publicado na web em 22/9/10 IDENTIFICATION OF MICROCISTIN LR AT THE MOLECULAR LEVEL USING ATOMIC FORCE MICROSCOPY. Microcystins are non-ribosomal peptides that must be detected for its health concern. Here, microcystin LR and its specific antibody were respectively tethered to the substrate and to the tip of an atomic force microscope, after surface functionalization using 3-aminopropyltriethoxysilane and glutaraldehyde. Functionalization was confirmed comparing topographic images taken on bare and modified tips. Force versus distance curves were successfully used to measure the specific antibody-antigen interactions comparing with a control in which microcystin was initially blocked by incubation with free antibodies. The results showed unequivocally the specific recognition of MLR, suggesting that this method could be useful for biosensor development.

A highly specific and sensitive nanoimmunosensor for the diagnosis of neuromyelitis optica spectrum disorders

“…AFM rectangular cantilevers of silicon nitride (AC40, Bruker, Nano Inc., Billerica, USA) were used with spring constant ( k ) of 0.02 N.m −1 and tip radius of 8 nm, suitable for force curve measurements 41 , and mica sheets (TedPella Inc., Redding, USA) of 15 × 15 mm 2 were cleaned in UV/Ozone radiation (ProCleaner TM , UV.PC.220, Bioforce Nanosciences, Ames, USA) during 20 min. Both surfaces were aminated with 3-aminopropyltrietoxisilane (APTES) and triethylamine (Sigma-Aldrich®, St. Louis, USA), following an established protocol 13,42,43 .…”