Differential effect of chelation on the pH tolerance of corneal epithelium in tissue culture

D. R. Meyer, James P McCulley

Research output: Contribution to journalArticle

3 Citations (Scopus)

Abstract

The impact of chelation on the biocompatibility of various vehicles was determined after 1- to 32-min exposures using stratified rabbit corneal epithelial cultures. Each formulation ws tested at either pH 5.0 or 7.5 to mimic the specifications of most commercial ophthalmic preparations. Adding ethylenediamine tetraacetic acid (EDTA) to balanced salt solutions was unremarkable, and all of the formulations were essentially nontoxic. In contrast, EDTA moderately reduced the toxicity of the acidic acetate/citrate-buffered vehicles, but enhanced the toxicity of the alkaline solutions. The preservative, on the other hand, had little impact on the biotolerance of acidic unbuffered and phosphate-buffered vehicles, although it also increased the toxicity of the alkaline formulations. These findings are interpreted in terms of the different pK(a) values of the chelating agents, and an unsuspected interaction between citrate and the preservative. We believe that this type of testing can be used to develop guidelines for the use of buffers, excipients and preservatives in commercial formulations.

Original languageEnglish (US)
Pages (from-to)204-212
Number of pages9
JournalOphthalmic Research
Volume23
Issue number4
StatePublished - 1991

Fingerprint

ethylenediamine
Corneal Epithelium
Citric Acid
Acids
Excipients
Chelating Agents
Buffers
Acetates
Salts
Phosphates
Guidelines
Rabbits

Keywords

  • Chelation
  • Corneal epithelium
  • pH
  • Pharmaceutical formulations
  • Tissue culture
  • Topical drugs
  • Toxicity
  • Vehicles

ASJC Scopus subject areas

  • Ophthalmology

Cite this

Differential effect of chelation on the pH tolerance of corneal epithelium in tissue culture. / Meyer, D. R.; McCulley, James P.

In: Ophthalmic Research, Vol. 23, No. 4, 1991, p. 204-212.

Research output: Contribution to journalArticle

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