Molecularly imprinted silica-silver nanowires for tryptophan recognition

Abstract

We report on silver nanowires (AgNWs) coated with molecularly imprinted silica (MIP SiO2) for recognition of tryptophan (Trp). The use of AgNWs as a template confers an imprinted material with adequate mechanical strength and with a capability of recognizing Trp due to its nanomorphology when compared to spherical microparticles with a similar surface-to-volume ratio. Studies on adsorption isotherms showed the MIP-SiO2-AgNWs to exhibit homogeneous affinity sites with narrow affinity distribution. This suggests that the synthesized material behaves as a 1D nanomaterial with a large area and small thickness with very similar affinity sites. Trp release from MIP-SiO2-AgNWs was demonstrated to be dominated by the diffusion rate of Trp as controlled by the specific interactions with the imprinted silica shell. Considering these results and the lack of toxicity of silica sol-gel materials, the material offers potential in the field of drug or pharmaceutical controlled delivery, but also in optoelectronic devices, electrodes and sensors.

A novel surface molecularly imprinted polymer as the solid-phase extraction adsorbent for the selective determination of ampicillin sodium in milk and blood samples

“…The surface molecularly imprinted polymers (SMIPs) are a new type of selective sorbent which is prepared by anchoring MIPs shells on the spherical surface (silica, chitosan or Fe 3 O 4 particles) via a surface molecular imprinting process [24] , [25] . The surface imprinted technique can get SMIPs with uniform morphology size, high specific surface, improved recognition, high binding capacity and fast mass transfer rate [26] , [27] .…”

Optical sensing of phenylalanine in urine via extraction with magnetic molecularly imprinted poly(ethylene-co-vinyl alcohol) nanoparticles

“…[28] The nanoparticles were examined directly by Raman spectroscopy to measure bound target, adding to the convenience of a potential sensing system. Other potential uses of such nanoparticles are in controlled drug release [29,30], and as artificial antibodies in biological systems and for bioimaging [22]. Note: the urine samples were diluted fivefold before measurement.…”

An Update on the Use of Molecularly Imprinted Polymers in Beta-Blocker Drug Analysis as a Selective Separation Method in Biological and Environmental Analysis

“…Magnetic nanoparticles are a type of nanoparticle (1-100 nm) with super-paramagnetism, unusual reactivity, and a huge specific surface area due to their nano size. Several nanoparticles, such as iron, nickel, cobalt, and their oxides, are employed as the core of the sorbents [95], with Fe 3 O 4 being one of the most commonly used [96][97][98]. Magnetic separation has several benefits, such as its strength and flexibility, ease of the separation procedure because it eliminates the centrifugation and/or filtration process, high efficiency, and high adsorption [98].…”