Uses of Colloidal Graphite Solutions

Photothermal excitation is a cantilever excitation method that enables stable and accurate operation for dynamic-mode AFM measurements. However, the low excitation efficiency of the method has often limited its application in practical studies. In this study, we propose a method for improving the photothermal excitation efficiency by coating cantilever backside surface near its fixed end with colloidal graphite as a photothermal conversion (PTC) layer. The excitation efficiency for a standard cantilever of PPP-NCHAuD with a spring constant of ≈40 N/m and a relatively stiff cantilever of AC55 with a spring constant of ≈140 N/m were improved by 6.1 times and 2.5 times, respectively, by coating with a PTC layer. We experimentally demonstrate high stability of the PTC layer in liquid by AFM imaging of a mica surface with atomic resolution in phosphate buffer saline solution for more than 2 h without any indication of possible contamination from the coating. The proposed method, using a PTC layer made of colloidal graphite, greatly enhances photothermal excitation efficiency even for a relatively stiff cantilever in liquid.

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Colloidal Graphite-Assisted Laser Desorption/Ionization MS and MSnof Small Molecules. 2. Direct Profiling and MS Imaging of Small Metabolites from Fruits

Analytical Chemistry ◽

10.1021/ac0706170 ◽

2007 ◽

Vol 79 (17) ◽

pp. 6575-6584 ◽

Cited By ~ 130

Author(s):

Hui Zhang ◽

Sangwon Cha ◽

Edward S. Yeung

Keyword(s):

Small Molecules ◽

Laser Desorption ◽

Laser Desorption Ionization ◽

Colloidal Graphite ◽

Desorption Ionization ◽

Ms Imaging

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Investigation of colloidal graphite as a matrix for matrix-assisted laser desorption/ionisation mass spectrometry of low molecular weight analytes

Journal of Mass Spectrometry ◽

10.1002/jms.3774 ◽

2016 ◽

Vol 51 (7) ◽

pp. 491-503 ◽

Cited By ~ 8

Author(s):

Alexander D. Warren ◽

Ulric Conway ◽

Christopher J. Arthur ◽

Paul J. Gates

Keyword(s):

Mass Spectrometry ◽

Molecular Weight ◽

Laser Desorption ◽

Low Molecular Weight ◽

Colloidal Graphite ◽

Ionisation Mass Spectrometry ◽

Ionisation Mass ◽

Matrix Assisted Laser ◽

Matrix Assisted Laser Desorption

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The Rate of Feeding by Mytilus in Different Kinds of Suspension

Journal of the Marine Biological Association of the United Kingdom ◽

10.1017/s0025315400023249 ◽

1949 ◽

Vol 28 (2) ◽

pp. 333-344 ◽

Cited By ~ 44

Author(s):

C. Barker Jørgensen

Keyword(s):

Particle Size ◽

Mytilus Edulis ◽

Feeding Rate ◽

Colloidal Graphite

The feeding rate of small specimens of Mytilus edulis (L.) has been determined in suspensions of colloidal graphite (‘Prodag’, grade ‘C’, and ‘Aquadag’, grade ‘S’), of flagellates, and of Nitzschia dosterium. The feeding rate was measured as the volume of water cleared from particles per unit time. In graphite suspensions, with particle size of about 4–5μ, as a rule only a small percentage of the particles was retained by the gills, whereas flagellates of about the same size were normally nearly all retained.

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