BIOMATERIALS LAB Drug Delivery Controlled Release Monday March
BIOMATERIALS LAB Drug Delivery & Controlled Release Monday, March 19 th and Tuesday, March 20 th BME 245/445 – Lab 4
PRE-LAB § Sign-in § Quiz (Lin. 2009) BME 245/445 – Lab 4
Big Picture: Drug Delivery § Control drug delivery rate, dose & location Toxic Level Drug Concentration Therapeutic Range With Delivery Device Period of Efficacy Traditional Delivery Time BME 245/445 – Lab 4
Big Picture: Drug Delivery § Monolithic Device § Drug is released by diffusion out of polymer matrix § Release rate depends on: § § Drug loading Drug size Mesh size Shape of device http: //www. sigmaaldrich. com/materials-science/biomaterials/tutorial. html § Applied in Norplant – implantable contraceptive device § Release hormone over 5 years § Discontinued – unpopular, not cost-effective BME 245/445 – Lab 4
LINEAR MOLECULES § PEGMA (2, 10, 20 k. D) § Increase number of repeat units (n) § Alter mesh size and thus rate of BSA release Small Mesh Size Large Mesh Size BME 245/445 – Lab 4
METHACRYLATE POLYMERIZATION Step-growth Polymerization 1 “Arm” PEG MA (Lin, C. C. , Pharmaceutical Research. 26(3): 631 -643. 2009) BME 245/445 – Lab 4
SECTION 1 PEGMA Network Synthesis 1. 10 wt% PEGDA in PBS+BSA (10 mg/m. L) 2. 10% photo-initiator by volume (LAP) 3. 40μL placed in 1 m. L syringe (tip cut off) § to create cylindrical hydrogel sample geometry 4. exposed to UV-lamp for 10 min 5. Remove and place in PBS PEG (mg) 28. 3 PBS solution (μl) 225 Initiator (μl) 25
SECTION 2 Protein Collection Time Course (done by TA) § BSA in hydrogel will release into surrounding PBS § PBS will be routinely changed (stored in -80°C freezer) § BSA concentration will be assessed for total release BME 245/445 – Lab 4
SECTION 3 Protein Detection Assay – Coomassie § Compared unknowns to known [BSA] standards § Measure Absorbance at 590 nm BME 245/445 – Lab 4
From plate reader…. Absorbance at 590 nm PEG MW Sample 2 k. Da # 10 k. Da 20 k. Da 1 2 … n BME 245/445 – Lab 4
% BSA released What we are interested in…. Time BME 245/445 – Lab 4
Theoretical Governing Eqns Drug diffuses out z=L/2 Drug diffuses out z=0 BME 245/445 – Lab 4
Drug Concentration CA C 0 0 Governing Eqns z=0 time z=L BME 245/445 – Lab 4
Simplifying Governing Eqns BME 245/445 – Lab 4
Mesh Size Calculations BME 245/445 – Lab 4
Safety § General § PEG/PBS/BSA are relatively benign § Lab glasses, gloves, closed toed shoes § No food, no drinks, no applying makeup
LAB TEAMS- Monday TEAM A 2 k TEAM B 2 k TEAM C 10 k TEAM D 10 k TEAM E 20 k Ripa Chowdhury Chris Farrar Matt Hazelett Caressa Chen Ruth Davis Eric Comeau Christine Mclin Rachel Rakvica Tonima Quabili Corinne Lampe Margaret Fettis Kristen Harding Yi Rao Ka Lai Tsang Mitchell Long Andrea Wong Stephen Zhang Chris Schmitt Bingqing Wang BME 245/445 – Lab 4
LAB TEAMS- Tuesday TEAM F 2 k TEAM G 10 k TEAM H 20 k Team I 20 k Ibrahima Bah Raymond Goo Seung Hoon Lee Alex Kotelsky Joseph Mozingo Sara Nowacki David Narrow Jennifer Williams Carly Sombric Spencer Putnam Erin Schnellinger Yoon-Suk Yi Nicole Varble Shijie Zhong Sean Rodriguges Sijia Zhang Douglas Clift Robert Mcwhorter Shijie Zhong BME 245/445 – Lab 4
- Slides: 18