Impact of Various Hydrophobic Cargoes on the Structural Properties of Pluronic-F127 Based Micelles near the Standard Critical Transition Zone
Pluronic F-127 is a triblock copolymer (PEO-PPO-PEO) that can form a micelle at critical micelle concentration (CMC). CMC for Pluronic F-127 is 0.7% at 25 0C. Micelles are lipid molecules that can arrange themselves in a spherical form in an aqueous solution with a hydrophobic core and hydrophilic shell. Pluronic F-127 can encapsulate poor water-soluble drugs and administrate the medicine to the targeted area with a controlled drug release rate and low toxicity. The purpose of this study is to understand the structural variation in Pluronic F-127 micelles after loading with different hydrophobic cargoes (alkanes, fatty acids, anticancer therapeutic agents). Different preparation methods have been applied to get a homogenous solution of samples. Temperature and concentration have been varied in near-critical micellar transition zone to observe the phase transition. SAXS (Small Angle X-ray Scattering) is used to get the scattering intensity profile of samples, and then data is processed and reduced by Foxtrot and Mantidplot software. Finally, all structural variation has investigated using core-shell hard-sphere, core-shell Hayter MSA, and core-shell Guinier Porod models. The purpose of this work is to investigate radius, thickness, SLD, volume fraction, and other structural parameters and getting a transparent idea about the micellar interaction near-critical micellar zone, which has a promising contribution to improving drug encapsulation and drug release at a controlled rate. The scattering intensity profile of samples provides strong evidence of micelle formation near CMC and CMT (critical micellization temperature). The radius of the core increases proportionally with longer alkane chain. pH value decreased with increased Linoleic acid concentration and structural parameters are fully reversible with temperature variation. For temperature-dependent samples, micelle formation has been observed around 20-30 0C and sol-gel transition around 35-40 0C.
Condensed matter physics|Polymer chemistry
Iqbal, Tahmida Raheen, "Impact of Various Hydrophobic Cargoes on the Structural Properties of Pluronic-F127 Based Micelles near the Standard Critical Transition Zone" (2021). ETD Collection for University of Texas, El Paso. AAI28541485.