Lyophilised nanovesicles loaded with vitamin B-12

The use of nanomaterials in recent years has shown many advantages for the production of pharmaceuticals, cosmetics, food, and food packaging. Nanovesicles are emerging as carriers of bio-compounds and drugs at a wide variety of applications due to the hydrophilic and lipophilic character of the structure: an aqueous core surrounded by a lipid layer. In this work, vitamin B-12 (cobalamin) was encapsulated, due to its synergic activity with antibiotics. Moreover, this bio compound is present in several food products and pharmaceuticals products. A freeze-drying process is proposed for nanocarriers developments, due to its advantages for storage and transportation. Three types of vesicles formulations were tested: liposomes, niosomes and positively charged niosomes. Maltodextrin at 20 % concentration (w/w) was added to the formulation to protect the vesicles during the lyophilisation process. The nanovesicles particle size and morphology was characterized by Dynamic Light Scattering and Transmission Electron Microscopy, and the encapsulation efficiency by HPLC with UV-vis's detection. The lyophilised powder was resus-pended in three aqueous phases: pure water, glycerol and PEG400 aqueous solutions. An increase in the mean vesicle size was observed as a general trend. It was also studied the effect of adding vitamin B-12 before or after the lyophilisation step on mean vesicles size, results indicated that vesicles were less affected in size when vitamin B-12 was added before the lyophilisation step. Moreover, encapsulation efficiency (EE) of vitamin B-12 in lyophilised vesicles arise values up to 70 % while the loading capacity (LC) of these systems were 100 mg/g, values obtained for liposomes when PEG400 solution was used as hydrat-ing media, showing that the method developed for loaded lyophilised nanocarriers do not alter EE and LC. (C) 2022 Published by Elsevier B.V.