Ali Rassouli; Sakineh Khanamani Falahatipour; Yalda Hosseinzadeh Ardakani; Hamid Akbari Javar; Katayoun Kiani
Abstract
BACKGROUND: Frequent drug dosing and animal handling are usually required in conventional antimicrobial therapy but sustained release formulations can improve compliance. OBJECTIVES: This study aimed to evaluate the pharmacokinetic (PK) parameters of a novel sustained release enroflox-acin (ENR) ...
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BACKGROUND: Frequent drug dosing and animal handling are usually required in conventional antimicrobial therapy but sustained release formulations can improve compliance. OBJECTIVES: This study aimed to evaluate the pharmacokinetic (PK) parameters of a novel sustained release enroflox-acin (ENR) hydrogel in comparison to a conventional ENR formulation in rabbit animal model. METHODS: A total of 20 rabbits were randomly divided into three groups and received a single dose of ENR or blank by subcutaneous (SC) injection as following: Group 1 (n=8) received ENR (10 mg/kg) using a conventional product (Enrovet®); Group 2 (n=8) received ENR (33.3 mg/kg) using a hydrogel formulation; and Group 3 or control group (n=4) received equal volumes of a blank hydrogel formulation. Blood samples were collected at different time points post-dosing. ENR concen-trations in plasma were estimated by high-performance liquid chromatographic (HPLC) method and PK parameters were calculated using a non-compartmental analysis. RESULTS: The ENR hydrogel released the drug in a sustained manner with mean residence time (MRT) of 78.4 ± 15.3 h, which was significantly more than that of the conventional formulation (7.39 ± 2.37 h, p <0.05). However, maximal plasma concentration (Cmax) for ENR hydrogel (1.41 ± 0.76 μg/mL) was significantly less than that of the conventional product (2.86 ± 0.79 μg/mL). The relative bioavailability (Frel) was not significantly different between the two formula-tions. CONCLUSIONS: The hydrogel formulation significantly increased the MRT of ENR. Hence, it could be a promising delivery system to prolong the pharmacological activity of ENR in animals and enhance compliance.
Katayoun Kiani; Ali Rassouli; Yalda Hosseinzadeh Ardakani; Hamid Akbari Javar; Sakineh Khanamani Falahatipour; Pegah Khosraviyan; Taghi Zahraee Salehi
Abstract
Background: Sustained release delivery system can reduce the dosage frequency and maintain the therapeutic level of drugs for a longer time. Biodegradable, biocompatible and thermosensitive chitosan-beta-glycerophosphate (C-GP) solutions can solidify at body temperature and maintain their physical integrity ...
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Background: Sustained release delivery system can reduce the dosage frequency and maintain the therapeutic level of drugs for a longer time. Biodegradable, biocompatible and thermosensitive chitosan-beta-glycerophosphate (C-GP) solutions can solidify at body temperature and maintain their physical integrity for a longer duration. OBJECTIVES: To develop a novel delivery system based on the integration of liposomes in hydrogel using mesoporous silica nanoparticles (MSNs) for sustained release of danofloxacin in farm animals. METHODS: The MSNs were prepared using N-cetyltrimethylammonium bromide and tetraethylortho silica. The liposomes were prepared by thin film hydration method. C-GP solution containing danofloxacin-loaded MSN liposomes underwent different in-vitro tests, including evaluation of the entrapment efficiency, gelation time, morphology, drug release pattern as well as antimicrobial activities against S. aureus and E. coli. RESULTS: The mean pore size of MSNs was 2.8 nm and the mean MSN entrapment efficiency was 45%. Kinetics of danofloxacin release from liposomal hydrogel followed the Higuchi’s model. This formulation was capable of sustaining the danofloxacin release for more than 96 h. The FTIR studies showed that there were no interactions between danofloxacin and hydrogel excipients. Scanning electron microscopy (SEM) showed that the formed gel had a continuous texture, while the swelled gel in the phosphate buffer had a porous structure. Microbiological tests revealed a high antibacterial activity for lipomosal hydrogel of danofloxacin-loaded MSN comparable with danofloxacin solution. CONCLUSIONS: The liposomal hydrogel solidified at body temperature, effectively sustained the release of danofloxacin and showed in vitro antibacterial effects.