Potential Oscillations Related to Proton Concentration in Formaldehyde Oxidation

We report a small molecule enzyme pair for optical voltage sensing via quenching of bioluminescence. This Quenching Bioluminescent Voltage Indicator, or Q-BOLT, pairs the dark absorbing, voltage-sensitive dipicrylamine with membrane-localized bioluminescence from the luciferase NanoLuc (NLuc). As a result, bioluminescence is quenched through resonance energy transfer (QRET) as a function of membrane potential. Fusion of HaloTag to NLuc creates a two-acceptor bioluminescence resonance energy transfer (BRET) system when a tetramethylrhodamine (TMR) HaloTag ligand is ligated to HaloTag. In this mode, Q-BOLT is capable of providing direct visualization of changes in membrane potential in live cells via three distinct readouts: change in QRET, BRET, and the ratio between bioluminescence emission and BRET. Q-BOLT can provide up to a 29% change in bioluminescence (ΔBL/BL) and >100% ΔBRET/BRET per 100 mV change in HEK 293T cells, without the need for excitation light. In cardiac monolayers derived from human induced pluripotent stem cells (hiPSC), Q-BOLT readily reports on membrane potential oscillations. Q-BOLT is the first example of a hybrid small molecule – protein voltage indicator that does not require excitation light and may be useful in contexts where excitation light is limiting.

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A Small Molecule – Protein Hybrid for Voltage Imaging via Quenching of Bioluminescence

10.26434/chemrxiv.13426412 ◽

2020 ◽

Author(s):

Brittany Benlian ◽

Pavel Klier ◽

Kayli Martinez ◽

Marie Schwinn ◽

Thomas Kirkland ◽

...

Keyword(s):

Energy Transfer ◽

Membrane Potential ◽

Small Molecule ◽

Resonance Energy Transfer ◽

Resonance Energy ◽

Live Cells ◽

Potential Oscillations ◽

Excitation Light ◽

Voltage Imaging ◽

Induced Pluripotent

We report a small molecule enzyme pair for optical voltage sensing via quenching of bioluminescence. This Quenching Bioluminescent Voltage Indicator, or Q-BOLT, pairs the dark absorbing, voltage-sensitive dipicrylamine with membrane-localized bioluminescence from the luciferase NanoLuc (NLuc). As a result, bioluminescence is quenched through resonance energy transfer (QRET) as a function of membrane potential. Fusion of HaloTag to NLuc creates a two-acceptor bioluminescence resonance energy transfer (BRET) system when a tetramethylrhodamine (TMR) HaloTag ligand is ligated to HaloTag. In this mode, Q-BOLT is capable of providing direct visualization of changes in membrane potential in live cells via three distinct readouts: change in QRET, BRET, and the ratio between bioluminescence emission and BRET. Q-BOLT can provide up to a 29% change in bioluminescence (ΔBL/BL) and >100% ΔBRET/BRET per 100 mV change in HEK 293T cells, without the need for excitation light. In cardiac monolayers derived from human induced pluripotent stem cells (hiPSC), Q-BOLT readily reports on membrane potential oscillations. Q-BOLT is the first example of a hybrid small molecule – protein voltage indicator that does not require excitation light and may be useful in contexts where excitation light is limiting.

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Shock-Tube Kinetics Studies of Formaldehyde Oxidation Reactions Involving NO2, NO, and N2O with and without O2.

10.21236/ada129014 ◽

1983 ◽

Author(s):

K. G. P. Sulzmann

Keyword(s):

Shock Tube ◽

Oxidation Reactions ◽

Kinetics Studies ◽

Formaldehyde Oxidation

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Galvanostatic dissolution of mercury from the surface of glassy carbon into thiocyanate solution

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19800169 ◽

1980 ◽

Vol 45 (1) ◽

pp. 169-178 ◽

Cited By ~ 2

Author(s):

František Opekar ◽

Karel Holub

Keyword(s):

Glassy Carbon ◽

Electrode Surface ◽

High Current Density ◽

High Current ◽

Nernst Equation ◽

Potential Oscillations ◽

Thiocyanate Solution ◽

Theoretical Assumptions ◽

Solution Proceeds ◽

Dissolution Current

The galvanostatic dissolution of mercury from the surface of glassy carbon into a thiocyanate solution proceeds in accord with theoretical assumptions, as manifested by the constant product of the dissolution current and transition time. Under certain relations between the amount of oxidised mercury and concentration of thiocyanate at the electrode surface, however, a small part of the mercury dissolves at more positive potentials than correspond to the Nernst equation. This dissolution can be accompanied by potential oscillations. The anomalous behaviour is elucidated by the concept about coverage of a certain part of mercury with a film of sparingly soluble compounds of SCN- ions with mercury. This film is formed at the end of the galvanostatic dissolution on certain places of the electrode surface covered with mercury droplets, where SCN- ions are much exhausted as a result of a high current density.

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Study of potential oscillations during reaction of an aluminium single crystal with an aqueous KOH solution

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19900345 ◽

1990 ◽

Vol 55 (2) ◽

pp. 345-353 ◽

Cited By ~ 4

Author(s):

Ivan Halaša ◽

Milica Miadoková

Keyword(s):

Aqueous Solutions ◽

Single Crystal ◽

Single Crystals ◽

Periodic Potential ◽

Optimum Conditions ◽

Potential Oscillations ◽

Dilute Aqueous Solutions ◽

Experimental Findings ◽

Kinetics Of

The authors investigated periodic potential changes measured on oriented sections of Al single crystals during spontaneous dissolution in dilute aqueous solutions of KOH, with the aim to find optimum conditions for the formation of potential oscillations. It was found that this phenomenon is related with the kinetics of the reaction investigated, whose rate also changed periodically. The mechanism of the oscillations is discussed in view of the experimental findings.

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Hierarchical nanostructures self-assembled from δ-MnO2 ultrathin nanosheets and Mn3O4 octahedrons for efficient room-temperature HCHO oxidation

New Journal of Chemistry ◽

10.1039/d0nj05515h ◽

2021 ◽

Author(s):

Lifang Qi ◽

Yao Le ◽

Chao Wang ◽

Rui Lei ◽

Tian Wu

Keyword(s):

Room Temperature ◽

Hierarchical Nanostructures ◽

Low Level ◽

Ultrathin Nanosheets ◽

Self Assembling ◽

Formaldehyde Oxidation ◽

Self Assembled

Self-assembling ultrathin active δ-MnO2 nanosheets and Mn3O4 octahedrons into hierarchical texture enhances room-temperature formaldehyde oxidation at a low-level of Pt.

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