Ciprofloxacin kinetic release profiles of cements composed of HAp1 and HAp2 alone and HAp1 and HAp2 mixed in 85/15 and 50/50 weight ratios (a). Linear fits of the release data for the four different cements, including HAp2 (b), HAp1/HAp2 50/50 (c), HAp1/HAp2 85/15 (d) and HAp1 (e), to the Korsmeyer–Peppas model, from which the Korsmeyer–Peppas exponent, n, was derived. Variation in the parameter n and the release rate constant, km, as a function of the content of HAp1 in the mixed cements (f).