title: Fluorescence of commercial Pluronic F127 samples: Temperature-dependent micellization.
abstract: We present a novel approach of using the butylated hydroxytoluene (BHT) antioxidant found in commercial Pluronic F127 samples as a marker of polymer aggregation. The BHT marker was compared to the pyrene dye and static light scattering methods as a way to measure the critical micelle concentration (CMC) and critical micelle temperature (CMT). The n→π(∗) transitions of BHT are sensitive to the microenvironment as demonstrated by plotting the fractional intensities of its excitation (≈280nm) and emission (≈325nm) peaks. BHT is more sensitive to changes in temperature than concentration. The partition coefficient increases ≈40-fold for pyrene compared to ≈2-fold for BHT when the temperature is increased from 25 to 37°C. CMT values determined using the BHT fluorescence decrease with increasing F127 concentration. Our results show that BHT can be used as a reliable marker of changes in the microenvironment of Pluronic F127.
authors.affiliation: Division of Biochemistry, School of Medicine, Loma Linda University, Loma Linda, CA 92350, United States. chperry@llu.edu
authors.forename: Christopher C
authors.initials: CC
authors.lastname: Perry
authors.forename: Theodore S
authors.initials: TS
authors.lastname: Sabir
authors.forename: Wesley J
authors.initials: WJ
authors.lastname: Livingston
authors.forename: Jamie R
authors.initials: JR
authors.lastname: Milligan
authors.forename: Qiao
authors.initials: Q
authors.lastname: Chen
authors.forename: Victoria
authors.initials: V
authors.lastname: Maskiewicz
authors.forename: Danilo S
authors.initials: DS
authors.lastname: Boskovic
mesh_terms: D000975:Antioxidants / Q000737:chemistry; D002084:Butylated Hydroxytoluene / Q000737:chemistry*; D005453:Fluorescence; D008823:Micelles; D020442:Poloxamer / Q000737:chemistry*; D013696:Temperature
chemical_list: D000975:Antioxidants; D008823:Micelles; D020442:Poloxamer; D002084:Butylated Hydroxytoluene