High-precision drop shape analysis (HPDSA) of quasistatic contact angles on silanized silicon wafers with different surface topographies during inclining-plate measurements: Influence of the surface roughness on the contact line dynamics

To quantitate surface hydrophobicity of the intestine, we measured contact angles formed with water droplets in multiple regions of rabbit intestine at varying ages (suckling, weanling, and adult) and after dinitrochlorobenzene-induced colitis. Contact angles were measured using novel methods: axisymmetric drop-shape analysis-contact diameter for contact angles less than 90 degrees and axisymmetric dropshape analysis-maximum diameter for contact angles greater than 90 degrees. To determine whether mucus was present on the surface of intestine used, indirect immunofluorescence was performed using antibody specific to goblet cell mucin. To confirm that intestinal mucus could be responsible for the physical properties of surface mucosa, surface tensions of mucus prepared from distal ileum, distal colon, and inflamed distal colon of adult rabbits were measured by axisymmetric drop-shape analysis on pendant drops. Contact angles of adult small intestine [duodenum, 38.0 +/- 11.2 degrees (SD); jejunum, 44.0 +/- 22.9 degrees; ileum, 56.4 +/- 23.3 degrees] were less than proximal colon (93.2 +/- 6.7 degrees; P less than 0.05) and distal colon (86.4 +/- 24.2 degrees; P less than 0.05). Contact angles on proximal colon from suckling rabbits (53.2 +/- 8.4 degrees) were less than both weanling (93.2 +/- 23.3 degrees; P less than 0.05) and adult rabbits (93.2 +/- 6.7 degrees; P less than 0.05). Contact angles on inflamed adult distal colon (54.7 +/- 20.6 degrees) were decreased from values on normal distal colons (86.4 +/- 24.2 degrees). Indirect immunofluorescence demonstrated that mucin was present in both vacuoles of goblet cells and on the colonic surface.(ABSTRACT TRUNCATED AT 250 WORDS)

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Automation of axisymmetric drop shape analysis for measurements of interfacial tensions and contact angles

Colloids and Surfaces ◽

10.1016/0166-6622(90)80286-d ◽

1990 ◽

Vol 43 (2) ◽

pp. 151-167 ◽

Cited By ~ 376

Author(s):

P. Cheng ◽

D. Li ◽

L. Boruvka ◽

Y. Rotenberg ◽

A.W. Neumann

Keyword(s):

Shape Analysis ◽

Contact Angles ◽

Drop Shape ◽

Interfacial Tensions ◽

Axisymmetric Drop Shape Analysis

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A New Approach for Study of pH- Solubility Profile of Bleached Shellac Film by Drop Shape Analysis

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1060.141 ◽

2014 ◽

Vol 1060 ◽

pp. 141-144 ◽

Cited By ~ 1

Author(s):

S. Saengsod ◽

Manee Luangtana-Anan

Keyword(s):

Contact Angle ◽

Shape Analysis ◽

Contact Line ◽

Buffer Solution ◽

Simple Method ◽

Drop Shape ◽

Solubility Profile ◽

Angle Method ◽

Bleached Shellac

The aim of this study was to apply contact angle method for the determination of the pH solubility profile of bleached shellac film. Various pH of buffer solution was dropped on the bleached shellac film and drop shape analysis was investigated. The changes in the contact angle and contact line were recorded during 10-min measurement. The graphs of change in slope –obtained from plot between contact angle and time-and % change in contact line were plotted against various pH. The results illustrated the slight change in slope and % change in contact line at low pH while the significant change was reported at high pH. The results were in agreement with % dissolved film at various pH. The bleached shellac film started to dissolve at pH 7. The higher % dissolved film was obtained at pH 8 and 9 and at pH 10 was completely dissolved. Therefore, the contact angle method by the drop shape analysis, a simple method and less solvent used, can be an indicator for determination of pH solubility profile of bleached shellac. The result obtained could then be applied to the other substances.

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