title: Spontaneous temperature-sensitive Pluronic(®) based niosomes: Triggered drug release using mild hyperthermia.
abstract: Inclusion of lipids or polymers with a transition temperature closer to physiological body temperature (40-42°C) is a strategy used in tumor therapy for more than 30 years, because it allows induction of drug release from delivery systems by mild hyperthermia. Unfortunately, most of these thermo-sensitive carriers are removed from circulation before completion of their function. Thus, novel multi-functional niosomes possessing spontaneous stealth and thermo-sensitive properties were developed from L64 Pluronic(®) and L64ox as its derivative, in presence or absence of cholesterol. The use of L64 both as amphiphilic constituent and thermo-sensitive molecule, gave the possibility to bypass the use of additional excipients and increased the system biocompatibility. Niosomes diameter ranged from 400 to 750nm and were long term stable. Calcein and 5-FU possess great affinity to niosomal matrices rich in PEO groups. Negative Z-potential values were attributed to the negative charges onto the niosomes surface and generally change according to the temperature. The in vitro drugs release studies were performed at 25°C, 37°C and 42°C, that are representative of certain conditions (storage, physiological condition and mild hyperthermia, respectively). Results showed that L64-based niosomes possess spontaneous thermo-sensitive properties: drugs releases were found to be more pronounced at 42°C. These early results are a promising first step for the development of multi-functional devices that combine several advantages such as stealth properties and temperature controllability at the desired location and time, for a more specific and efficient pharmacological therapy.
authors.affiliation: Department of Pharmacy, Health and Nutritional Sciences, University of Calabria Via Pietro Bucci, Ed. Polifunzionale, 87036 Arcavacata di Rende, Italy.
authors.forename: Lorena
authors.initials: L
authors.lastname: Tavano
authors.affiliation: Department of Chemistry and Chemical Technologies, University of Calabria Via Pietro Bucci, 87036 Arcavacata di Rende, Italy.
authors.forename: Cesare
authors.initials: C
authors.lastname: Oliviero Rossi
authors.affiliation: Department of Pharmacy, Health and Nutritional Sciences, University of Calabria Via Pietro Bucci, Ed. Polifunzionale, 87036 Arcavacata di Rende, Italy.
authors.forename: Nevio
authors.initials: N
authors.lastname: Picci
authors.affiliation: Department of Pharmacy, Health and Nutritional Sciences, University of Calabria Via Pietro Bucci, Ed. Polifunzionale, 87036 Arcavacata di Rende, Italy. Electronic address: rita.muzzalupo@unical.it.
authors.forename: Rita
authors.initials: R
authors.lastname: Muzzalupo
mesh_terms: D002784:Cholesterol / Q000737:chemistry; D004337:Drug Carriers; D065546:Drug Liberation; D004355:Drug Stability; D005452:Fluoresceins / Q000737:chemistry / Q000493:pharmacokinetics*; D005472:Fluorouracil / Q000737:chemistry / Q000493:pharmacokinetics*; D008081:Liposomes / Q000737:chemistry*; D010316:Particle Size; D020442:Poloxamer / Q000737:chemistry*; D013696:Temperature
chemical_list: D004337:Drug Carriers; D005452:Fluoresceins; D008081:Liposomes; D020442:Poloxamer; D002784:Cholesterol; C514452:pluronic L64; D005472:Fluorouracil; C007740:fluorexon
keywords: Drug release; Hyperthermia; Niosomes; Pluronic(®); Thermo-sensitivity