Protamine/heparin optical nanosensors based on solvatochromism

Abstract

Novel optical nanosensors for the selective detection of the polycationic protamine based on solvatochromic signal change allow one to detect heparin in plasma.

Recent improvements to the selectivity of extraction-based optical ion sensors

“…This then alters its local polarity and changes the absorption of the solvatochromic dye, providing an optical readout. 61 The two proposed sensing mechanisms depend on whether protamine accumulates at the surface or is extracted and are illustrated in Fig. 6 .…”

“…Fig.6Reproduced from Soda et al61 Proposed protamine (polycationic protein) detection mechanisms using a hyperpolarization-based sensor. The highly localised charge of DNNS strongly polarizes the solvatochromic dye, an interaction that is only interrupted by polyions that either localize in (i) or on (ii) the particle.…”

Chloride ion-selective dye liquid nanoemulsion: improved sensor performance due to intermolecular interactions between dye and ionophore

“…Plasticized PVC membranes or nanoemulsions containing lipophilic dyes and other functional materials, such as ionophores, have been used as optical sensors (optodes). [1][2][3][4][5][6][7][8][9][10][11] Our group developed a single-step microanalytical device using an optode which was highly sensitive with respect to ion sensing, 12,13 biosensing, 14 and immunoassays. 15 In general, conventional optodes are prepared by dissolving solid lipophilic dyes in a plasticizer.…”

“…20 In recent years, many studies on nanoscale optodes have been reported. [6][7][8][9][10][11] Of these, nanoemulsion-type optodes (NE optodes) have various advantages. 6,[22][23][24][25][26][27] For instance, their response times are significantly shortened owing to their large specific surface area.…”

Mass Transfer from Ion-Sensing Component-Loaded Nanoemulsions into Ion-Selective Membranes: An Electrochemical Quartz Crystal Microbalance and Thin-Film Coulometry Study

“…As an example, some ion-selective optical nanosensors are based on a spectral absorption shift of a solvatochromic dye induced by the solution polarity difference that is driven by the concentration change of the ion of interest. 5,6 Single-entity electrochemistry also utilizes encapsulated NEs in combination with a redox probe to study singleparticle collision events during electron or ion transfer reactions. 4,7 Recently, our group proposed a new approach to prepare ion-selective membranes (ISMs) that relies on membrane doping through nanoemulsions loaded with appropriate sensing components.…”