[Effect of excipients on the preparation and properties of antibiotic solution for intravenous application]

To evaluate the effect of excipients disodium-edetate dihydrate and citric acid monohydrate on rate of antibiotic powder dissolution, particle size after dissolution and chemical stability of the product after reconstitution with water for injection and 5% glucose solution.

The product containing excipients (Tazocin) was compared with generic products without excipients. Rate of dissolution was evaluated organoleptically and spectrophotometrically, particle size was determined microscopically after reconstitution and after 4 hours of standing at laboratory temperature and chemical stability was assessed by HPLC.

Tazocin dissolved significantly faster in both solvents compared to products without excipients (3-4 min versus 10-13 min). The limit for maximal number of particles larger than 25 mm in the reconstituted solution was not exceeded in any of the products either after using water for injection or after using 5% glucose, both after reconstitution and after 4 hours of standing at laboratory temperature. Nevertheless, only for Tazocin the number of unwanted larger particles decreased in time in both solvents. Disodium-edetate dihydrate and citric acid stabilized the dissolved particles of the active substance and prevented its transformation into the insoluble form, which results in lower number of unwanted large particles. Tazocin was more stable, but the stability was not significantly better than its generic products.

Disodium-edetate dihydrate and citric acid monohydrate (and possibly the used method of lyophilisation) therefore have a positive effect on the preparation and properties of antibiotic solution for intravenous application.