Evaluation of the pH, titratable acidity and viscosity of various brands of syrups sampled from various pharmacy stores in Benin.
Uyi M. Ogbeide Emeka A. Okorie, Henry A. Okeri
Department of Pharmaceutical Chemistry, Faculty of Pharmacy, University of Benin, Benin City, Edo State, Nigeria.
Corresponding author : Uyi M. Ogbeide
Email:uyi.ogbeide@uniben.edu; Phone: +234(0)7038058676
ABSTRACT
Background: For so long now, medicated syrups have been used in paediatric practice for the treatment of disease conditions, as palliatives and even as food supplements / haematinics. Pharmaceutical firms sweeten liquid preparations with sucrose to aid compliance, and this in turn increases their viscosity. Some of the constituents of these syrups are acidic and are capable causing erosion of the dentiture.
Objectives This in vitro study aims to evaluate the endogenous pH, titratable acidity and viscosity of different syrups sampled from different pharmacy stores in Benin City.
Methods Sixteen (16) commonly used syrups were evaluated. The pH of each syrup was determined using a digital pH meter. The titratable acidity was assessed by titrating 0.1 N sodium hydroxide solution against 30 ml of each syrup until a pH of 8.2 was reached. The viscosity of the syrups was determined using a suspended level viscometer.
Results The pH of the syrup brands ranged from 3.25 to 6.18. All the syrups had an acidic pH and 82% of the samples showed pH below the critical value of 5.5 which is capable of causing enamel dissolution. The titratable acidity of the syrups ranged from 0.93-7.50 g/100 ml while the kinematic viscosity of the syrups ranged from 6.51- 2 -1 75.96 mm S .
Conclusion The outcome of this study confirms that all syrups investigated had high values of pH, titratable acidity and viscosity.
Keywords: Tiratable acidity, syrups, viscosity, pH, enamel dissolution.