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Articles 1 - 9 of 9
Full-Text Articles in Physical Sciences and Mathematics
Potential Driven Deposition Of Poly(Diallyldimethylammonium Chloride) Onto The Surface Of 3-Mercaptopropionic Acid Monolayers Assembled On Gold, Wesley Sanders, Mark Anderson
Potential Driven Deposition Of Poly(Diallyldimethylammonium Chloride) Onto The Surface Of 3-Mercaptopropionic Acid Monolayers Assembled On Gold, Wesley Sanders, Mark Anderson
Mark R. Anderson
Electrochemical impedance spectroscopy (EIS) and quartz crystal microbalance (QCM) measurements are used to examine the ability of applied potential to drive the ionic self-assembly of poly(diallyldimethylammonium) chloride (PDDA) onto a substrate modified with a monolayer of 3-mercaptopropionic acid (3-MPA). The potential of zero charge (PZC) of the gold electrode modified with a monolayer of 3-MPA was found by differential capacitance measurements to be −0.12 (±0.01) V versus Ag−AgCl. Changing the substrate potential to values positive (−0.01 V vs Ag−AgCl) of the PZC induces interfacial conditions that are favorable for the electrostatic deposition of cationic polymers onto the surface of 3-MPA …
Impedance Of Contact-Printed Alkanethiol Self-Assembled Monolayers On Gold, Leslie Adamczyk, Mark Anderson
Impedance Of Contact-Printed Alkanethiol Self-Assembled Monolayers On Gold, Leslie Adamczyk, Mark Anderson
Mark R. Anderson
Contact printing (CP) is a common method for creating modified interfaces having two-dimensional patterns. The popularity of this method is due to the ease and low cost of this method. When printing an interfacial pattern with n-alkanethiols, the desired properties are those of a homogeneous, solution deposited monolayer. Patterning a surface, however, may cause defects to occur within the monolayer where two thiol domains meet. If large enough, the activity of these areas can dominate the electrochemical response. Creating patterned monolayer modified interfaces, therefore, may generate vast user defined domain boundaries that impact the electrochemical behavior of the modified interface …
Potential Driven Polyelectrolyte Adsorption Onto Monolayer Modified Electrodes, Mark Anderson, Weslie Sanders
Potential Driven Polyelectrolyte Adsorption Onto Monolayer Modified Electrodes, Mark Anderson, Weslie Sanders
Mark R. Anderson
Preparation of interfacial structures by molecular self-assembly has been actively studied for many years. Well-defined modified interfaces can be used to study fundamental interfacial properties, or they can be used in different practical applications. To broaden the utility of interfaces prepared by molecular self-assembly, monolayers containing terminal functionality are frequently used. These interfaces have structural and physical properties that can be controlled by both the identity of the functionalization as well as the ensemble structure of the modified interface. This suggests that the chemical and physical properties of an interface can be designed and/or controlled to some extent by altering …
Potential Driven Polyelectrolyte Adsorptoin Onto Monolayer Modified Electrodes, Mark Anderson
Potential Driven Polyelectrolyte Adsorptoin Onto Monolayer Modified Electrodes, Mark Anderson
Mark R. Anderson
No abstract currently available.
Characterization Of Carboxylic Acid-Terminated Self-Assembled Monolayers By Electrochemical Impedance Spectroscopy And Scanning Electrochemical Microscopy, Wesley Sanders, Ricardo Vargas, Mark Anderson
Characterization Of Carboxylic Acid-Terminated Self-Assembled Monolayers By Electrochemical Impedance Spectroscopy And Scanning Electrochemical Microscopy, Wesley Sanders, Ricardo Vargas, Mark Anderson
Mark R. Anderson
Electrochemical impedance spectroscopy (EIS) and scanning electrochemical microscopy (SECM) are used to monitor changes in the ionization of monolayers of 11-mercaptoundecanoic acid. When using an anionic redox probe, Fe(CN)6−4, the charge-transfer resistance of the 11-mercaptoundecanoic acid monolayer-modified interface increases in a sigmoidal fashion as the solution is made basic. The opposite effect is observed when using a cationic redox probe. The inflection points of these two titration curves, however, differ when using the different redox probes. This result is taken as being characteristic of the influence that applied potential has on the ionization of the monolayer. The role of substrate …
Simultaneous Determination Of Glucose And L‐Glutamate Using A Capillary Enzyme Reactor With Electrochemical Detection, Stephanie Hooper, Mark Anderson
Simultaneous Determination Of Glucose And L‐Glutamate Using A Capillary Enzyme Reactor With Electrochemical Detection, Stephanie Hooper, Mark Anderson
Mark R. Anderson
An electrophoresis capillary that incorporates two enzymes for the simultaneous determination of glucose and l-glutamate is described. The enzymes deposited along the separation capillary walls react with their respective substrate as they are separated during the electrophoresis to produce hydrogen peroxide that is detected by amperometry as the hydrogen peroxide zone emerges from the end of the capillary. Even though both enzyme reactions produce a common product, hydrogen peroxide, the hydrogen peroxide produced by each enzyme reaction stays in narrow zones that migrate the length of the capillary at different rates. The rate of migration for the individual H2O2 zones …
Manipulating Interfacial Structure And Properties, Mark Anderson
Manipulating Interfacial Structure And Properties, Mark Anderson
Mark R. Anderson
No abstract is available at this time.
Selective Formation Of A Symmetric Sc3n@C78 Bisadduct: Adduct Docking Controlled By An Internal Trimetallic Nitride Cluster, Ting Cai, Liaosa Xu, Chunying Shu, Hunter Champion, Jonathan Reid, Clemins Anklin, Mark Anderson, Harry Gibson, Harry Dorn
Selective Formation Of A Symmetric Sc3n@C78 Bisadduct: Adduct Docking Controlled By An Internal Trimetallic Nitride Cluster, Ting Cai, Liaosa Xu, Chunying Shu, Hunter Champion, Jonathan Reid, Clemins Anklin, Mark Anderson, Harry Gibson, Harry Dorn
Mark R. Anderson
In this paper we report a regioselective Bingel−Hirsch reaction of Sc3N@C78 yielding a single mono- and a dominate bis-ethyl malonate derivative for the first time. The Cs-symmetric monoadduct 1 and C2v-symmetric bisadduct 2 were isolated by HPLC and characterized by MS, UV−vis, and NMR spectroscopy. The symmetric bisadduct 2 clearly demonstrate the remarkable regioselectivity control exerted by the encapsulated Sc3N cluster. We have employed a LUMO electron density surface computational approach to predict multiadduct docking sites on the ellipsoidal fullerene cage surface.
Application Of A Square‐Wave Potential Program For Time‐Dependent Amperometric Detection In Capillary Electrophoresis, Stephanie Hooper, David Roach, Mark Anderson
Application Of A Square‐Wave Potential Program For Time‐Dependent Amperometric Detection In Capillary Electrophoresis, Stephanie Hooper, David Roach, Mark Anderson
Mark R. Anderson
Use of a square-wave potential program for time-dependent amperometric detection of analyte zones in capillary electrophoresis (CE) is described. Electrochemical detection for CE requires that the separation field be isolated from that of the electrochemical detection. This is generally done by physically separating the CE separation field from that of the detection. By applying a time variant potential program to the detection electrode, the detector current has a time dependence that can be used to help isolate the electrochemical detection current from that of the separation. When using a 20 μm inner-diameter capillary, we find that a square-wave potential program …