GARCIA SANHUEZA, CAMILO ANDRES
Email Address
Birth Date
Search Results
Molecularly imprinted nanoparticles assay (MINA) in pseudo ELISA: An alternative to detect and quantify octopamine in water and human urine samples
In 2004, octopamine was added to the list of drugs banned by the world anti-doping agency (WADA) and prohibited in any sport competition. This work aims to develop a new analytical method to detect octopamine in water and human urine samples. We proposed a pseudo-enzyme-linked immunosorbent assay (pseudo-ELISA) by replacing traditional monoclonal antibodies with molecularly imprinted polymer nanoparticles (nanoMIPs). NanoMIPs were synthesised by a solid-phase approach using a persulfate initiated polymerisation in water. Their performance was analysed in pseudo competitive ELISA based on the competition between free octopamine and octopamine-HRP conjugated. The final assay was able to detect octopamine in water within the range 1 nmol·L-1-0.1 mol·L-1 with a detection limit of 0.047 ± 0.00231 ?g·mL-1 and in human urine samples within the range 1 nmol·L-1-0.0001 mol·L-1 with a detection limit of 0.059 ± 0.00281 ?g·mL-1. In all experiments, nanoMIPs presented high affinity to the target molecules and almost no cross-reactivity with analogues of octopamine such as pseudophedrine or l-Tyrosine. Only slight interference was observed from the human urine matrix. The high affinity and specificity of nanoMIPs and no need to maintain a cold chain logistics makes the nanoMIPs a competitive alternative to antibodies. Furthermore, this work is the first attempt to use nanoMIPs in pseudo-ELISA assays to detect octopamine. © 2019 Elsevier B.V., All rights reserved.
Synthesis and characterization of a novel colorimetric and fluorometric probe Turn-on for the detection of Cu2+ of derivatives rhodamine
A new Rhodamine-based Turn On fluorescent probe (E)- 3?,6?-bis(diethylamino)-2-((2,5-dimethoxybenzylidene)amino)spiro[isoindoline-1,9?-xanthen]-3-one (WGB) was synthesized. Results show that WGB is selective for Cu2+ cations, forming a WGB-Cu2+ complex in a 2:1 stoichiometry, confirmed through density functional theory (DFT) electronic structure calculations and reactive molecular dynamics (MD) simulations. Theoretical calculations agreed with the experimental data. The detection limit of WGB-Cu+2 complex is 6.76 × 10-8 M. Preliminary studies employing epifluorescence microscopy demonstrate that Cu2+ can be imaged in neuroblastoma SH-SY5Y cells treated with WGB. © 2022 Elsevier B.V., All rights reserved.