CSA743 - Practical Report Assessment - Pharmacy Research Assignment - Research Assignment

Internal Code: MAS5372

Research Assignment:

Scenario: The high performance liquid chromatography system consisted of a Prostar 230 solvent delivery module, Prostar 335 UV detector and Prostar 410 autosampler. The Shodex OHpak SB-802.5 HQ 8 mm×300 mm size exclusion column was used for the separation of enoxaparin and heparin. Samples were analyzed with 0.3M sodium sulfate (pH adjusted to 5.0 with 0.1 M HCl) as a mobile phase with a flow rate of 0.26 mL/minute. Samples were diluted to1 mg/mL with mobile phase before injection of 15 ?l. Detection was carried out at 230 nm. Instrument control and data acquisition were carried out using Star Chromatography Workstation software. Questions:  In clinical practice, the efficacy of heparin is determined using biological assays such as anti-factor Xa (AFXa) and AFIIa. Why is it not appropriate to determine the clinical efficacy of heparin based on its plasma concentration (mg/ml or ?g/ml or gm/l etc.)? 2. Fondaparinux is a new synthetic pentasaccharide ultra low-molecular-weight heparin. Do you think it is possible, at least in theory, to determine fondaparinux clinical efficacy based on its plasma concentration rather than AFXa activity? 3. In week 5, the linearity of AFXa assay (estimated using correlation coefficient ) was investigated using 0, 0.2, 0.4 and 0.8 IU/ml of heparin solution. Linearity was found to be lower than 0.90. Discuss, in detail, why the obtained r2 value was lower than the anticipated value. Use chromatograms and linearity graph(s) to support your answer.   4.a. Describe the methodology you used to perform AFXa assay in week 7. b. Describe the working principle of AFXa assay. 5. Discuss THREE distinct limitations of high-performance size-exclusion chromatography when used for the analysis of glycosaminoglycans. 6. Enoxaparin is a low-molecular-weight heparin and has an average molecular weight of 4500Da. Heparin has an average molecular weight of 15000 to 20000Da. High-performance size-exclusion chromatograms of enoxaparin and heparin are shown in Figure 1 and 2, respectively. Scenario 2: Linezolid, a type of oxazolidinone, is an antibacterial agent used for the treatment of infections caused by bacteria resistant to penicillins and cephalosporins. It is also used for the treatment of infections in patients allergic to penicillins and/or cephalosporins.  Aimed to conduct a study investigating the physicochemical stability of linezolid in three different types of peritoneal dialysis solutions (namely, Physioneal®, Extraneal® and Dianeal®) at three different temperatures for various time points. Questions: a. The stability of linezolid in three different types of peritoneal dialysis solutions should be investigated at which THREE temperatures? Discuss why is it important to investigate the stability of linezolid at the temperatures you have listed above. b. Discuss the importance of developing and validating the stability indicating assay for the stability determination of linezolid in three different types of peritoneal dialysis solutions at three temperatures for various time points. c. List the stability indicating parameters you would consider while validating the developed method? Discuss why it is important to consider the parameters you have listed above.