The Role of pH and Ionic Strength in the Attraction–Repulsion Balance of Fibrinogen Interactions

SummaryThe ethanol (EtOH) stability of skim milk and the stability towards aggregation of casein micelles diluted into ethanolic buffer solutions were compared using data obtained from previously published experiments. Differences in absolute stability and in relative response were observed when Ca2+ level and pH were adjusted, the buffer system results lying below those from skim milk in both cases. Increasing the ionic strength of skim milk adjusted to pH 7·0 lowered its EtOH stability whereas increasing the ionic strength of the diluting buffer increased the stability of the casein micelles. The hypothesis is put forward that the differences are due to the simultaneous precipitation of Ca phosphate when EtOH is added to skim milk. This draws calcium from the caseinate sites of the micelle, counteracting the destabilizing effects of the EtOH towards the micelle. Such removal and the consequent restructuring are kinetically controlled and micellar precipitation in skim milk finally occurs when the micellar coagulation time falls within the time scale of the restructuring reactions.

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The role of polarization-induced reorientation of DNA strands on organic field-effect transistor-based biosensors sensitivity at high ionic strength

Applied Physics Letters ◽

10.1063/1.4930303 ◽

2015 ◽

Vol 107 (10) ◽

pp. 103301 ◽

Cited By ~ 13

Author(s):

S. Lai ◽

M. Barbaro ◽

A. Bonfiglio

Keyword(s):

Ionic Strength ◽

Field Effect ◽

Field Effect Transistor ◽

High Ionic Strength ◽

Organic Field Effect Transistor ◽

Dna Strands ◽

Effect Transistor

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Rheology of bentonite dispersions: Role of ionic strength and solid content

Applied Clay Science ◽

10.1016/j.clay.2021.106275 ◽

2021 ◽

Vol 214 ◽

pp. 106275

Author(s):

Yuan Lin ◽

Huaitao Qin ◽

Jin Guo ◽

Jiawang Chen

Keyword(s):

Ionic Strength ◽

Solid Content

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Attachment of the flagellate Giardia lamblia: role of reducing agents, serum, temperature, and ionic composition

Molecular and Cellular Biology ◽

10.1128/mcb.2.4.369-377.1982 ◽

1982 ◽

Vol 2 (4) ◽

pp. 369-377

Author(s):

F D Gillin ◽

D S Reiner

Keyword(s):

Sodium Chloride ◽

Ionic Strength ◽

Oxygen Tension ◽

Giardia Lamblia ◽

Bovine Serum ◽

Ionic Composition ◽

Short Term ◽

Reduced Temperature

The flagellated protozoan Giardia lamblia has been grown only in highly complex media under reduced oxygen tension. Therefore, the organic and physiological requirements for in vitro attachment and short-term (12-h) survival of this organism were determined. In defined maintenance media, a thiol reducing agent (e.g., cysteine) was absolutely required for attachment and survival of this aerotolerant anaerobe. The crude bovine serum Cohn III fraction greatly stimulated attachment and survival. Attachment was decreased at a reduced temperature (24 degrees C as compared with 35.5 degrees C) and absent at 12 degrees C or below. Attachment and survival were strongly dependent upon pH and ionic strength, with optima at pH 6.85 to 7.0 and 200 to 300 mosmol/kg. Sodium chloride was better tolerated than KC1. Reduction of Ca2+ and Mg2+ to below 10(-8) M did not significantly affect attachment.

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