Lab 4 Assignment Details: Drug dissolution from an immediate release vs modified release preparation There are four tasks that need to be completed as part of your assignment for this lab session. Plot the calibration graph and using linear regression analysis, determine the equation ofthe line and linear correlation coefficient (10 marks). 2. Calculate the % drug released at each time point on the basis of the theoretical dose of drug (200mg). Present your findings as arithmetic mean ± standard deviation for both the immediate release and the modified release preparation. (20 marks) 3. Determine a possible model to describe the drug release/drug dissolution from the two preparations studied by plotting the following relationships (use mean values for this): (a) mg drug released = f(time) (b) In (mg drug released) = f (time) (c) mg drug released = f (square root of time) (d) mg drug released = f (cube root of time) [zero order process] [first order process] [Higuchi square root law] [Hixon-Crowell cube root law] The most likely model to describe the drug release would result in a straight line in one of these four graphs. (Note, however, that due to the complexity of the dissolution process the models often only describe some part of it i.e. a straight line is obtained in between a certain time span only.) On the basis of the most suitable model, for the modified release formulation predict the times, where 50%, 75% and 95% drug would have been released, using the correct numerical expression/time law (30 marks) 4. Discuss briefly (max. 400 words) the effect of formulation design on the drug release pattern exhibited by the two dosage forms (40 marks 9