Aggregation-based fluorescence amplification strategy: “turn-on” sensing of aminoglycosides using near-IR carbocyanine dyes and pre-micellar surfactants

Imaging-Guided Delivery of a Hydrophilic Drug to Eukaryotic Cells Based on Its Hydrophobic Ion Pairing with Poly(hexamethylene guanidine) in a Maleated Chitosan Carrier

“…Hydrophobic ion pairing is an appropriate type of binding for a hydrophilic drug when its imaging is required. As we have recently shown [21], HIPs (for example, formed by cephalosporin anion and cetyltrimethylammonium cation) can incorporate a hydrophobic dye with a considerable fluorescence enhancement. We synthesized [21] a new series of pentamethine carbocyanine dyes with appropriate hydrophobicity to be solubilized in the HIPs.…”

“…As we have recently shown [21], HIPs (for example, formed by cephalosporin anion and cetyltrimethylammonium cation) can incorporate a hydrophobic dye with a considerable fluorescence enhancement. We synthesized [21] a new series of pentamethine carbocyanine dyes with appropriate hydrophobicity to be solubilized in the HIPs. In aqueous buffer solution, the dye exists as nanoparticles, and its fluorescence is quenched (aggregation-induced quenching [22]).…”

“…We consider that these systems could be suitable for non-covalent imaging of a hydrophilic drug as a component of the ion pair. The incorporated dye-containing fluorescent HIPs ("ternary aggregates" [21]), when placed in an appropriate nanocarrier, may indicate the position of the drug in the organism. Moreover, it will be possible to observe the nanocontainer lysis that might be predictably accompanied by a change in the quantum yield of the IR fluorophore upon contact with the internal milieu.…”

“…The purpose of this study is to assess the feasibility in application of the dye-containing chitosan-encapsulated ternary aggregates for the delivery of a hydrophilic drug to eukaryotic cells. We used ceftriaxone as a model drug, which is known to form [21] stable ternary aggregates with CTAB and capable of fluorescence enhancement of a pentamethyne carbocyanine dye. We replaced the toxic surfactant (CTAB) used as a counter-ion in [21] with a cationic polymer-oligomer poly(hexamethylene guanidine) (PHMG).…”

Средства Визуализации Доставки Лекарственных Веществ С Использованием Анионированных Хитозанов

“…Хитозан образует комплексы (К) с флуоресцирующими тройными агрегатами доставляемое вещество -противоион -гидрофобный карбоцианиновый краситель (см. структуру), обнаруженными нами ранее [2]. Обнаружено, что комплексы К, сшитые глутаровым альдегидом, устойчивы -время разрушения в режиме диализа составило более часа.…”