Advances in electrochemical and optical polyion sensing: A review

Potentiometric Sensing

“…Meyerhoff's group recently published a thorough review about key accomplishments in electrochemical and optical sensing of polyions over the past 25 years. 179 The authors discussed the basic sensing principles of single-use and fully reversible polymeric membrane-type potentiometric polyion sensors, voltammetric polyionsensitive electrodes, and single-use polyion-sensitive optodes. In the last two years the same group significantly contributed to the development of the analytical protocols for the quantification of polyquaterniums (PQs), polymeric quaternary ammonium salts.…”

Pentamethinium Salts Nanocomposite for Electrochemical Detection of Heparin

“…CV voltammograms were measured on the modified GC electrodes when the composite mixture AuNPs/PMS1 dispersed either methanol or tetrahydrofuran and deposited on the surface of the GC electrode, after being covered with the PVC-plasticized membrane ( Figure 5 ). It should be noted that Meyerhoff et al [ 18 ] reported the first detection of heparin by using a PVC layer. Therefore, we can suppose that the proposed method can be suitable for sensing heparin in a biological matrix.…”

“…However, only the electrode modified with AuNPs/PMS1 dispersed in THF can be used for the voltammetric determination of heparin in the field of a higher concentration range (31.37–45.02 IU mL −1 ). Tetrahydrofuran is a solvent that is traditionally used for the preparation of plasticized poly(vinyl chloride) (PVC) membranes [ 18 ]. One of the advantages of tetrahydrofuran is its ability to rapidly evaporate after deposition on the electrode surface.…”

“…Heparin is used as an anticoagulant drug able to accelerate the rate at which antithrombin inhibits serine proteases in the blood coagulation cascade [ 16 , 17 ]. Recently, various electrochemical sensors have been reported to detect heparin using an ion-exchanger mechanism [ 18 ]. In this paper, we report the detection of heparin using voltammetric sensors based on pentamethinium salts’ nanocomposite.…”

Nanoscale electrostatic gating of molecular transport through nuclear pore complexes as probed by scanning electrochemical microscopy

“…Ion-selective SECM tips based on liquid/liquid microinterfaces (Fig. 2) were prepared by filling glass micropipettes with a nitrobenzene (NB) solution of charged ionophores for the polyions,42 protamine and Arixtra, and a supporting organic electrolyte, tetradodecylammonium tetrakis(pentafluorophenyl)borate (TDATFAB). The interfaces were formed with a low salt buffer (LSB) containing 1 mM KCl, 0.5 mM MgCl 2 , and 10 mM HEPES at pH 7.5 (ref.…”