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Study of acid–base equilibria of fleroxacin
Journal of Pharmaceutical and Biomedical Analysis, 1998The acid-base equilibria of fleroxacin were studied by means of potentiometry and spectrophotometry. It was established that fleroxacin undergoes a complex acid-base equilibrium due to its zwitterionic nature and two proton-binding sites of similar acidity.
G, Popović +2 more
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Principles of Acid-Base Equilibria
2022Abstract This chapter describes the basic concepts of acids and bases, including different ways to define them, the differences between strong and weak acids and bases, and the relevant equilibrium expressions. The underlying principles involved in solving acid-base equilibrium problems is a major focus of the chapter.
Patrick L. Brezonik, William A. Arnold
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Microscopic acid—base equilibria of arginine
Talanta, 1991Three and two protonation macroconstants as well as twelve and four microconstants have been determined for arginine and citrulline, respectively. These data include microscopic basicity values of the arginine guanidino group, for which no reliable constants have been reported earlier.
B, Noszál, R, Kassai-Tánczos
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Acid-Base Equilibria of Minoxidil
Analytical Letters, 1991Abstract Minoxidil, (2, 4-diamino-6-piperidinopyrimidine-3-oxide) a potent orally active antihypertensive agent, has been studied. The acid-base behaviour has been investigated above pH = 2, where this compound is stable. At lower acidity levels, a protonation equilibrium takes place, leading to pK = − 0.285 ± 0.018 when freshly prepared solutions were
B. García +3 more
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Tryptophan as a probe for acid–base equilibria in peptides
Peptide Science, 2003AbstractWe present results of time resolved fluorescence measurements performed in Tryptophan (Trp) derivatives and Trp‐containing peptides in the pH range 3.0–11.0. For each compound a set of decay profiles measured in a given range of pH values was examined as a whole, using the global analysis technique. The data were fitted to two or three lifetime
Cássia Alessandra, Marquezin +3 more
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Acid—base equilibria of β-blockers in acetonitrile
Journal of Pharmaceutical and Biomedical Analysis, 1990The acid-base equilibria of a series of beta-adrenoceptor blocking drugs in acetonitrile have been studied, and pKHB+ values determined. The theory of such titrations is discussed and simple potentiometric and visual methods in acetonitrile media are proposed for the assay of beta-adrenoceptor blocking drugs.
J, Barbosa, V, Sanz-Nebot, M E, Torrero
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1982
Our discussion of acid—base equilibria will use the Bronsted-Lowry definition of an ACID as a proton donor, and a BASE as a proton acceptor.
David A. Robinson, John McK. Woollard
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Our discussion of acid—base equilibria will use the Bronsted-Lowry definition of an ACID as a proton donor, and a BASE as a proton acceptor.
David A. Robinson, John McK. Woollard
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Acid—base equilibria in clay suspension
Journal of Colloid and Interface Science, 1979Abstract The thermodynamics governing the equilibria of weakly basic compounds in dilute clay suspensions is developed in considerable detail. Quantities suitable for characterizing the equilibrium are shown to be: Keff, an apparent equilibrium constant for the acid—base reaction in suspension; Δ G BH + , and Δ G B ,
Joseph R Feldkamp, Joe L White
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Redox properties and acid–base equilibria of zucchini mavicyanin
Journal of Inorganic Biochemistry, 2001The reduction potential of mavicyanin isolated from zucchini peelings, which is a blue copper protein belonging to the subclass of the phytocyanins, has been determined through direct electrochemistry as a function of temperature and pH. The enthalpy and entropy changes accompanying protein reduction were found to be very similar with those determined ...
BATTISTUZZI, Gianantonio +6 more
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The acid-base equilibria of carbonic anhydrase
Inorganica Chimica Acta, 1980Abstract The electronic spectra of cobalt substituted bovine and human carbonic anhydrase B have been recorded both in ion free solutions and in presence of ‘non interacting’ buffers, at different pH values. The water proton longitudinal relaxation times in solution of the cobalt substituted human enzyme have also been measured as a function of pH ...
BERTINI, IVANO +2 more
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