Phenomenological and Formulation Aspects in Tailored Nanoliposome Production

Liposomes as cell‐mimetic system have attracted wide attention of researchers in various branches of the drug delivery topic as they can be highly functionalized and personalized, thus solving the major drawbacks of bioactive molecules linked to their low stability, limited membrane permeability, short half‐life and low bioavailability. The development of sustainable processes able to produce ad hoc liposomes in a rapid manner through the use of not‐laboured techniques, avoiding drastic conditions, is of great relevance for the industrial sector. In this chapter, two novel liposome production processes, the ultrasound‐assisted thin‐film hydration and the simil‐microfluidic techniques sharing the same size reduction/homogenization preparative step, are presented. The phenomenological aspects involved in vectors constitution through the duty cycle sonication process (bilayer rupture/vesicles formation mechanisms) and through the simil‐microfluidic approach (intubated flows interdiffusion mechanisms) are described. Finally, two applications as case histories involving the use of the developed techniques for relevant classes of active molecule delivery are described. In particular, a pharmaceutical application concerns the encapsulation of short‐interfering RNA (siRNA) molecule, used for gene therapy, inside cationic nanoliposomes, and a nutraceutical application consists in the production of ferrous sulphate anionic liposomal formulations with improved features compared to those already present on the market

Impact Of Pulsed Electric Field Pretreatment On Yield And Quality Of Lipid Extracted From Cephalothorax Of Pacific White Shrimp (Litopenaeus Vannamei) By Ultrasound Assisted Process

Impacts of pulsed electric field (PEF) pretreatment with different electric field strengths (4, 8, 12 and 16 kVcm-1 ) and pulse numbers (120, 160, 200 and 240) on extraction yield of lipid and cell disintegration index (Zc) of Pacific white shrimp cephalothorax were examined. PEF treated samples were subsequently subjected to lipid extraction using ultrasonic assisted extraction (UAE) process at ultrasonic amplitude of 91.2 microns for 25 min in continuous mode. Samples with PEF pretreatment and subjected to UAE rendered the highest lipid yield (30.34% dry basis). PEF pretreatment resulted in suppression of lipid oxidation as affirmed by the decreases in peroxide value (PV) and thiobarbituric acid reactive substances (TBARS). Lipid from PEF pretreated samples had higher content of PUFAs as well as carotenoids, which included astaxanthin, astaxanthin monoester, astaxanthin diester, canthaxanthin and β-carotene. Overall, PEF was a promising pretreatment to increase the yield and maintain the quality of lipid extracted from cephalothorax using UAE

Rapid on-Chip Assembly of Niosomes: Batch versus Continuous Flow Reactors

The large-scale continuous production of niosomes remains challenging. The inherent drawbacks of batch processes such as large particle polydispersity and reduced batch-to-batch reproducibility are here overcome by using commercially available microfluidic reactors. Compared to the traditional batch-based film hydration method, herein, we demonstrate that it is possible to carry out the homogeneous, large-scale (up to 120 mg/min) production of niosomes using two different synthesis techniques (the thin film hydration method and the emulsification technique). Niosomes particle size can be controlled depending on the need by varying the synthesis temperature. The high cytocompatibility of the resulting niosomes was also demonstrated in this work on three different somatic cell lines. For the first time, the structure of the niosome multilamellar shell was also elucidated using high-resolution transmission electron microscopy (HR-STEM) as well as their colloidal stability over time (6 weeks) under different storage conditions. The morphology of cryo-protected or as-made niosomes was also evaluated by HR-STEM after freeze-drying. Finally, the dual ability of those synthetic, nonionic, surfactant-based vesicles to carry both hydrophilic and hydrophobic molecules was also here demonstrated by using laser scanning confocal microscopy

Preface, BCREC Vol. 11 No. 1 Year 2016

DOI: 10.9767/bcrec.11.1.441.v-vi

Sonophotocatalytic degradation of sodium diclofenac using low power ultrasound and micro sized TiO2

The nonsteroidal anti-inflammatory drug sodium diclofenac (DC) is an emerging water pollutant which resists conventional wastewater treatments. Here the sonophotocatalytic degradation of DC was carried out using micrometric TiO2 (both pristine and Ag-decorated), UV-A irradiation and 20 kHz pulsed ultrasound. Sonophotocatalytic tests were compared with photolysis, sonolysis, sonophotolysis, sonocatalysis and photocatalysis data performed in the same conditions. A synergy index of over 2 was determined for tests with pristine TiO2, while values close to 1.3 were observed for Ag-TiO2. Reaction intermediates were studied by HPLC-MS, showing degradation mechanisms activated by hydroxyl radicals. Similar pathways were identified for photocatalytic and sonophotocatalytic tests, although the latter led to more oxidized compounds. Different reactor configurations (static and dynamic set ups) were studied. Sequential and simultaneous application of UV light and ultrasound led to similar performance. The role of water matrix was investigated using ultrapure and drinking water, showing marked detrimental effects of electrolytes on the DC degradation. Overall, the combined treatment proved more efficient than photocatalysis alone especially in demanding working conditions, like in drinking water matrices

Optimization of ultrasound-assisted extraction of pectinase enzyme from guava (Psidium guajava) peel: enzyme recovery, specific activity, temperature, and storage stability

This study aimed to investigate the effects of the ultrasound-assisted extraction conditions on the yield, specific activity, temperature, and storage stability of the pectinase enzyme from guava peel. The ultrasound variables studied were sonication time (10–30 min), ultrasound temperature (30–50°C), pH (2.0–8.0), and solvent-to-sample ratio (2:1 mL/g to 6:1 mL/g). The main goal was to optimize the ultrasound-assisted extraction conditions to maximize the recovery of pectinase from guava peel with the most desirable enzyme-specific activity and stability. Under the optimum conditions, a high yield (96.2%), good specific activity (18.2 U/mg), temperature stability (88.3%), and storage stability (90.3%) of the extracted enzyme were achieved. The optimal conditions were 20 min sonication time, 40°C temperature, at pH 5.0, using a 4:1 mL/g solvent-to-sample ratio. The study demonstrated that optimization of ultrasound-assisted process conditions for the enzyme extraction could improve the enzymatic characteristics and yield of the enzyme

Optimisation of ultrasound-assisted extraction of pectinase enzyme from Guava (Psidium guajava) peel: enzyme recovery, specific activity, temperature and storage stability

This study aimed to investigate the effects of the ultrasound-assisted extraction conditions on the yield, specific activity, temperature, and storage stability of the pectinase enzyme from guava peel. The ultrasound variables studied were sonication time (10–30 min), ultrasound temperature (30–50°C), pH (2.0–8.0), and solvent-to-sample ratio (2:1 mL/g to 6:1 mL/g). The main goal was to optimize the ultrasound-assisted extraction conditions to maximize the recovery of pectinase from guava peel with the most desirable enzyme-specific activity and stability. Under the optimum conditions, a high yield (96.2%), good specific activity (18.2 U/mg), temperature stability (88.3%), and storage stability (90.3%) of the extracted enzyme were achieved. The optimal conditions were 20 min sonication time, 40°C temperature, at pH 5.0, using a 4:1 mL/g solvent-to-sample ratio. The study demonstrated that optimization of ultrasound-assisted process conditions for the enzyme extraction could improve the enzymatic characteristics and yield of the enzyme

ULTRASOUND-ASSISTED EXTRACTION OF OIL FROM KIWIFRUIT (Actinidia Deliciosa) SEEDS

This study reports experimental kinetic data and modeling for the extraction of oil from kiwifruit seeds by ultrasound-assisted extraction (UAE) with ethanol. The fatty acid profile, tocopherol and total lipids content in the oil obtained were determined. The variables temperature and ultrasonic power were investigated based on the oil extraction yields using a central composite experimental design. The overall yields obtained were compared to conventional Soxhlet extraction with n-hexane and with ethanol. The extractions presented high extraction rates with overall yield ranged between 19 and 33%, and the extraction yields increased with the temperature. The fatty acid profile showed a high content of omega-3 fatty acids (63.20%) and the Vitamin E content was 14.97 ± 0.38 mg/100 g oil, with ɤ-tocopherol constituting 49% of the total tocopherol. A second-order kinetic model was applied to describe the ultrasound extraction process under different conditions. The numerical results were compared with the experimental extraction yields and presented a good correlation. The extraction technique investigated was found to be suitable for extraction of oil from kiwifruit seeds, in which the great potential of kiwifruit oil obtained from UAE was demonstrate