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Tablets & Capsules May 2018 39 using compaction forces between 2 and 15 kilonewtons. The tablets were then compared in terms of powder flow, ejection force, and functional tablet characteristics such as crushing strength and friability. Coated tablets with the same crushing strength as the reference product were pro- duced, and their disintegration time and dissolution profiles were ana- lyzed and compared with the original cetirizine tablets. Powder characteristics of dextrates and spray-dried lactose The similarities between the pow- der characteristics of dextrates and spray-dried lactose are shown in Table 1. Both are water-soluble, crys- tallized powders with a porous struc- ture and a spherical particle shape (Photo 2). The particle shape and high bulk density results in excellent powder flow for both materials. Furthermore, both excipients are appropriate for direct compression applications and mainly deform by brittle fracture. Cetirizine tablet reformulation The quantitative composition of the reformulated tablets is shown in Table 2. The proportion between MCC and lactose monohydrate in the original tablets was assessed by separating water-soluble and insolu- ble components and weighing them out. In addition to the API, the water-soluble fraction mostly con- tained lactose monohydrate, whereas the water-insoluble fraction chiefly consisted of MCC, resulting in rela- tive proportions of about 30 percent MCC and 59.7 percent lactose monohydrate. Furthermore, 1 per- cent silicon dioxide and 1 percent magnesium stearate were added to the formulation. The only difference between the lactose-based tablets and the dextrates-based tablets was the substitution of dextrates for lac- tose monohydrate. Results and discussion Powder flow and tablet character- istics of uncoated tablet cores. The lactose- and dextrates-based formula- tions showed similar results in terms of powder flow, ejection force, and compactibility (Figure 1). Both formu- lations had excellent flowability resulting in a very low Flodex index of 8 millimeters. The ejection force of both types of tablets remained below 200 newtons, even at a high compac- tion force of 15 kilonewtons, and an appropriate tablet hardness was obtained. Both formulations produced tablets with a very low friability. At moderate compaction forces (≥ 7 Photo 2: SEM pictures of dextrates (left) and spray-dried lactose (right) Table 2 Composition of reformulated cetirizine tablets (120 mg total weight) Notes: Vivapur is a registered trademark of JRS Pharma. Aerosil 300 is a registered trademark of Evonik, Essen, Germany. Ligamed MF-2-V is a registered trademark of Peter Greven, Bad Münstereifel, Germany. Vivacoat PC-1P-101 is a registered trademark of JRS Pharma. Ingredient Lactose-based formulation (%) Dextrates-based formulation (%) Cetirizine dihydrochloride 8.3 8.3 Microcrystalline cellulose Vivapur 102 30.0 30.0 Lactose monohydrate Spray-dried lactose 59.7 – Dextrates Non-GMO Emdex – 59.7 Silicon dioxide Aerosil 300 1.0 1.0 Magnesium stearate Ligamed MF-2-V 1.0 1.0 Opadry Y-1-7000 Vivacoat PC-1P-101 additional additional Total: 100.0 100.0 Table 3 Friability of lactose and dextrates-based tablets Friability (%) 2 kN 5 kN ≥7 kN Dextrates formulation N/A 0.06 < 0.1 Lactose formulation N/A 0.26 < 0.1