Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: KEGG:D03393 (Carbopol 934)
 103 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The electrophoretic mobility of nitrofurantoin (based on the microelectrophoresis method) has been studied in dilute dispersions of the drug. Specifically, the effect of NaCl, CaCl2 and AlCl3, pH, and a thickener, Carbopol 934, was determined. The electrophoretic mobility (mu) increases in absolute terms when the pH is raised between 3 and 9, although mu remains negative in this pH range. The variation of absolute mobility ([mu[) with NaCl concentration shows a pronounced maximum for a concentration of about 10(-4) M. However, when the concentration of CaCl2 in the medium is increased, [mu[ decreases steadily. The effect of AlCl3 concentration on the mobility is markedly influenced by the pH of the dispersing medium although a general trend is observed for mu to become more positive with increasing concentration of the salt. Finally, Carbopol 934 appears to impart an extra negative charge to the nitrofurantoin surface, since higher negative mobilities were measured in the presence of the polymer.
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PMID:Electrophoretic study of nitrofurantoin in aqueous suspensions. Effect of the addition of a polymeric thickener. 197 87

An experimental investigation is described of the electrokinetic properties of nitrofurantoin. The experiments are based on measurements of electrophoretic mobility in suspensions of this drug and the calculation of its zeta potential (zeta) following two different procedures. A simple mechanism is proposed for explaining the sign of the surface charge of nitrofurantoin and its increase with the pH of the medium. The effect on zeta of changes in the concentration of NaCl, CaCl2, or AlCl3 is studied for different pH values of the suspensions. The behavior of zeta in the presence of NaCl shows evidence of Cl- adsorption on the particles, especially at low electrolyte concentrations. The AlCl3 salt was capable of reversing the sign of the surface charge, changing it to positive when a given, pH-dependent concentration was added to the suspension. The effect of this salt on zeta for different pH values was probably due to the hydrolysis of the cation Al3+. A significant increase of the negative surface charge was observed when a small amount (0.1%) of a synthetic polymer, Carbopol 934, was present in NaCl or AlCl3 systems. This appears to indicate that the large polymer molecules adsorb on nitrofurantoin particles as part of their stabilizing mechanism.
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PMID:A study of the electrokinetic and stability properties of nitrofurantoin suspensions. I: Electrokinetics. 231 82