Role of the tracer in characterizing the aggregation behavior of aqueous block copolymer solutions using fluorescence correlation spectroscopy

Bioinspired Poly(2-oxazoline)s

“…The self-assembly of fluorescently labeled PMeOx-b-PNonOx copolymers was investigated in detail by Papadakis et al using fluorescence correlation spectroscopy (FCS) [57,58]. The PNonOx was found to be fully stretched by SANS while the PMeOx is coiled in the corona [59].…”

Poly(2‐oxazoline): eine Polymerklasse mit vielfältigen Anwendungsmöglichkeiten

“…[124] Selbst die Position des Fluoreszenzmarkers (am hydrophoben oder hydrophilen Block) hatte keinen Einfluss auf die Resultate, allerdings führte die Zugabe eines freien Markers zu einer ähnlichen CMC, aber einem kleineren hydrodynamischen Radius. [125] Diese Abweichung wurde mit der Aufteilung des freien Farbstoffs zwischen der Wasserphase und den Micellen erklärt. Kleinwinkel-Neutronenstreuung zufolge bilden die PMeOx-b-PNonOx-Copolymere kugelförmige Kern-SchaleMicellen, in denen der PNonOx-Kernblock gestreckt und der PMeOx-Koronablock spiralförmig vorliegen.…”

Fluorescence correlation spectroscopy in polymer science

“…178 The apparent increase of the radius was rather explained by the attachment of dyes to the micelles/aggregates. Binding of free dyes to micelles/aggregates is an equilibrium process and even though the chosen dyes are poorly watersoluble, and thus will be bound most of the time to the micelle/ aggregate, there are also periods of free diffusion.…”

“…Compared to other methods, FCS is especially powerful to detect a very low critical micelle concentration 174,[176][177][178][179] (CMC) and a very low critical aggregation concentration [176][177][178] (CAC) as they oen appear in block copolymers solutions. The sensitivity of FCS surpasses other uorescence spectroscopy methods such as evaluating the ratio between two absorption bands of pyrene to detect the local polarity of its surrounding and, thus, the appearance of incorporation into micelles.…”

“…Apart from the determination of the CMC, the average size of micelles and aggregates [176][177][178][179] can be studied using FCS. The obtained correlation time can be used to calculate the translational diffusion coefficient of the uorescent probe attached to the micelle using a reference of known diffusion coefficient.…”