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Hydrophobic ion pairing as a strategy to improve the encapsulation efficiency of PLGA nanoparticles.
Laviaha, Lizaveta ; Šnejdrová, Eva (advisor) ; Smékalová, Monika (referee)
Charles University Faculty of Pharmacy in Hradec Kralove Department of Pharmaceutical Technology Author: Lizaveta Laviaha Title of thesis: Hydrophobic ion pairing as a strategy to improve the encapsulation efficiency of PLGA nanoparticles. Supervisor: PharmDr. Eva Šnejdrová, Ph.D. Сonsultant: Mgr. Vladislav Frolov The aim of this thesis was to increase the encapsulation efficiency (EE) and capacity of PLGA nanoparticles (NPs) for the hydrophilic antibiotics gentamicin (GEN) and vancomycin (VAN). The method of hydrophobic ion pairing (HIP) and docusate sodium as anionic surfactant (AOT) were chosen. PLGA nanoparticles loaded with VAN or GEN, or their AOT complexes were prepared with optimized methods. Nanoparticles with VAN and GEN were prepared by the double-emulsion method (W1/O/W2), for GEN-AOT the single emulsion method (O/W) was used, and nanoparticles with VAN-AOT were prepared by suspension-emulsion method (S/O/W). Stable NPs with a size of 108 to 223 nm with a polydispersity lower than 0.2 were obtained. The influence of PLGA concentration on the size of NPs was found. The low zeta potential of the nanoparticles was related to steric stabilization by the non-ionogenic stabilizer Poloxamer 407. SEM images confirmed the spherical shape of the NPs. Encapsulation efficiency and loading capacity...
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Formulation of vancomycin loaded PLGA nanoparticles for local treatment of musculoskeletal infections II.
Ptáčková, Karolína ; Šnejdrová, Eva (advisor) ; Zbytovská, Jarmila (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical Technology Author: Karolína Ptáčková Title of thesis: Formulation of vancomycin loaded PLGA nanoparticles for local treatment of musculoskeletal infections II. Supervisor: PharmDr. Eva Šnejdrová, Ph.D. Consultant: Mgr. Vladislav Frolov The aim of the work was to formulate vancomycin hydrochloride (Van-HCl) loaded PLGA nanoparticles (NPs) using a double emulsion method for the local treatment of musculoskeletal infections. During preparation, selected critical formulation factors were modified and their influence on the characteristics of nanoparticles was studied. The size of the NPs determined by the DLS method ranged from 200 to 800 nm, the PDI was lower than 0.2 in most batches. The encapsulation efficiency (EE) determined by the direct method ranged from 2 % to 9 %. Glycerol monostearate at a concentration of 15 mg/ml proved to be a suitable primary emulsion stabilizer. The optimal concentration of PVA for stabilizing the nanosuspension was 30 mg/ml. The size of the NPs was influenced by the intensity of homogenization and the concentration of PVA. The concentration of Van-HCl, the organic solvent used and the intensity of homogenization led to an increase in EE. The DSC method confirmed that Van-HCl remains...
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Formulation of vancomycin loaded PLGA nanoparticles for local treatment of musculoskeletal infections I.
Petrášová, Ivana ; Šnejdrová, Eva (advisor) ; Smékalová, Monika (referee)
Charles University Faculty of Pharmacy in Hradec Kralove Department of Pharmaceutical Technology Author: Ivana Petrášová Title of thesis: Formulation of PLGA nanoparticles with vancomycin for local treatment of musculoskeletal infections I Supervisor: PharmDr. Eva Šnejdrová, Ph.D. The treatment of musculoskeletal infections requires the presence of high antibiotics concentration at the infection site. However, high doses of orally administered drugs cause the risk of increased systemic toxicity and serious adverse effects. Targeted drug delivery, currently one of the main areas of pharmaceutical research, represents a suitable option of a treatment without excessive burden on the organism. This diploma thesis focuses on the formulation of a therapeutic system for the local treatment of musculoskeletal infections in the form of polymer nanoparticles containing the antibiotic vancomycin. Due to the need of incorporation of a hydrophilic antimicrobial substance into them, the suspension-emulsion method of their preparation was used. Different concentrations of polyvinyl alcohol stabilizer and tripentaerythritol branched hydrophobic polymer poly(D,L- lactide-co-glycolide) were used for the preparation. Within the study the size of nanoparticles, polydispersity, zeta potential, encapsulation efficiency...
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