Standardization of Nanoparticle Characterization: Methods for Testing Properties,Stability, and Functionality of Edible Nanoparticles

There has been a rapid increase in the fabrication of various kinds of edible nanoparticles for oral delivery of bioactive agents, such as those constructed from proteins, carbohydrates, lipids, and/or minerals. It is currently difficult to compare the relative advantages and disadvantages of different kinds of nanoparticle-based delivery systems because researchers use different analytical instruments and protocols to characterize them. In this paper, we briefly review the various analytical methods available for characterizing the properties of edible nanoparticles, such as composition, morphology, size, charge, physical state, and stability. This information is then used to propose a number of standardized protocols for characterizing nanoparticle properties, for evaluating their stability to environmental stresses, and for predicting their biological fate. Implementation of these protocols would facilitate comparison of the performance of nanoparticles under standardized conditions, which would facilitate the rational selection of nanoparticle-based delivery systems for different applications in the food, health care, and pharmaceutical industries.     

Essential oil nanoemulsions: antibacterial activity in contaminated fruit juices

Many human acid tolerant bacterial and fungal pathogens can be transmitted through the consumption of the contaminated fruit juices. We aim to formulate essential oil nanoemulsions (basil, black seed, turmeric, clove & cinnamon), determine their ability to clear contamination by food borne bacterial pathogens from fruit juices. The antibacterial activity of the optimised formulations was tested in the fruit juices against bacterial pathogens causing gastrointestinal tract infections. The minimum bactericidal concentration (MBC) of clove emulsions ranged from 15.6 to 25 μL mL⁻¹. Cinnamon oil emulsion had an MBC ranging between 15 and 31 μL mL⁻¹. At MBC, cinnamon oil emulsions caused a 6log₁₀ decrease in viable counts by 8 h and maintained the sterility of fruit juices for 7 days at ambient temperature. Thus, clove and cinnamon microemulsions can be used as juice additives to control food borne bacterial pathogens and maintain the bacterial sterility of fruit juices.     

Utilisation of spontaneous emulsification to fabricate lutein‐loaded nanoemulsion‐based delivery systems: factors influencing particle size and colour

Factors influencing the formation and properties of lutein‐loaded nanoemulsions fabricated using spontaneous emulsification (SE) were investigated. Nanoemulsion formation depended on oil type: small droplets (diameter ≈ 200 nm) with a narrow monomodal particle size distribution (polydispersity index ≈ 0.23) could be formed using medium‐chain triglycerides (MCT), but not long‐chain triglycerides. Nanoemulsion formation also depended on surfactant type and concentration, with Tween 80 being the most effective surfactant. Optimisation of lutein‐loaded nanoemulsions formed by SE led to systems with a final composition of 10 wt% oil phase (0.12 wt% lutein + 9.88 wt% MCT), 10 wt% Tween 80, and 80 wt% aqueous phase. The nanoemulsions were stable to droplet aggregation when stored at ambient temperature for up to 1 month; however, some colour fading occurred due to lutein degradation. This study indicated the potential of nanoemulsion‐based delivery system fabricated using a low‐energy method for encapsulation and protection of lutein.     

Application of Oil/Water Nanoemulsions as a New Alternative to Demulsify Crude Oil

Oil-in-water nanoemulsions were developed and evaluated for effectiveness in breaking down crude oil emulsions. The nanoemulsions were prepared using two types of ethoxylated nonionic surfactants: nonylphenol and lauryl ether, at a concentration of 12 wt%, and the solvent xylene as the oil phase, at different concentrations (5, 7, and 10 wt%). The results of the demulsification tests showed that the nanoemulsions developed are a viable alternative to break down petroleum emulsions, with efficiency ranging from 90 to 95%. Also, the greater the xylene concentration in the nanoemulsion, the faster the demulsification process was.     

Controlled delivery of lipophilic agents to cell cultures for in vitro toxicity and biocompatibility assays

Synopsis
In this report, we present a novel method for delivering lipophilic compounds to cell cultures. The delivery system is based on a nanoemulsion stabilized by phospholipids. These nanoemulsions are well tolerated by cell cultures, such as TK6 lymphoblastoid cells and can be used to deliver defined amounts of encapsulated lipophilic compounds into cells.
We measured the growth inhibition of TK6 lymphoblastoid cells caused by different oils, UV-filters and fragrances to determine the biocompatibility or the toxicity of these compounds in simple cell culture experiments. Our data show that the applied nanoemulsion technology is also very suitable to study biological effects of the UV-A-irradiated compounds in cell culture assays.
Résumé
Dans ce compte-rendu, nous présentons une nouvelle méthode pour dispenser des composés lipophiles à des cultures de cellules. Le système de répartition est fondé sur une nanoémulsion stabilisée par des phospholipides. Ces nanoémulsions sont bien tolérées par les cultures cellulaires, comme les cellules lymphoblastoides TK6 et peuvent etre employées pour délivrer des quantités précises de composés lipophiles encapsulés aux cellules.
Nous avons mesuré l'inhibition de la croissance des cellules lymphoblastoides TK6 provoquée par diverses huiles, des filtres UV et des parfums pour déterminer la biocompatibilité ou la toxicité de ces composés par des essais sur de simples cultures de cellules. Nos données montrent que l'utilisation de la technologie des nanoémulsions convient également à l'étude des effects biologiques des composés irradiés par des UVA dans les cultures cellulaires.     

Formulation Optimization of a Palm-Based Nanoemulsion System Containing Levodopa

Response surface methodology (RSM) was utilized to investigate the influence of the main emulsion composition; mixture of palm and medium-chain triglyceride (MCT) oil (6%–12% w/w), lecithin (1%–3% w/w), and Cremophor EL (0.5%–1.5% w/w) as well as the preparation method; addition rate (2–20 mL/min), on the physicochemical properties of palm-based nanoemulsions. The response variables were the three main emulsion properties; particle size, zeta potential and polydispersity index. Optimization of the four independent variables was carried out to obtain an optimum level palm-based nanoemulsion with desirable characteristics. The response surface analysis showed that the variation in the three responses could be depicted as a quadratic function of the main composition of the emulsion and the preparation method. The experimental data could be fitted sufficiently well into a second-order polynomial model. The optimized formulation was stable for six months at 4 °C.     

Composite double network hydrogels with thermoresponsive colloidal nanoemulsions

We report the formulation and mechanical characterization of double network (DN) composite hydrogels. The first network consists of covalently crosslinked poly(ethylene glycol diacrylate) (PEGDA), which forms a strong, brittle network that provides elasticity to the gel. The second network, sodium alginate, is ionically crosslinked with Ca²⁺ to allow increased dissipation of mechanical energy. The novelty of this system over existing DN hydrogels is the additional incorporation of a third mesoscale network, composed of thermoresponsive poly(dimethyl siloxane) (PDMS) nanoemulsions, which undergo colloidal gelation through the bridging of the PEGDA hydrophobic end groups into the PDMS droplets. The colloidally gelled microstructures are photopolymerized into a solid hydrogel by crosslinking the precursors with ultraviolet (UV) light. Tensile mechanical experiments performed on the crosslinked DN nanoemulsion hydrogels show that their rupture stress (0.17–0.34 MPa), fracture energy (144–421 J/m²), and Young's modulus (1–2.1 MPa) are comparable to similar systems in the literature. These mechanical measurements suggest that the gels may be suitable for manufacturing processes in which large shear rates and deformations are encountered.     

Preliminary study on the development of nanoemulsions for carbamazepine intravenous delivery: an investigation of drug polymorphic transition

Carbamazepine (CBZ) is available on the pharmaceutical market as tablets, capsules, and oral suspensions, but not as a parenteral formulation for clinical use. Parenteral emulsions are a good alternative to poorly water-soluble drugs such as CBZ. In this way, four different emulsions containing 3 mg/mL of CBZ were developed, but during a period of storage, drug crystal precipitates appeared. To investigate this phenomenon, differential scanning calorimetry, infrared spectroscopy, and light microscopy were employed. The results suggested a polymorphic transition from β form to dehydrate form, resulting in drug precipitation, although the emulsions themselves remained stable for at least three months.     

Nanotechnology interventions in aquaculture and seafood preservation

Abstract

The inclusion of nanotechnologies in aquaculture and seafood preservation confronts a new edge that deserves attention in the recent trends of global food sector. Nanotechnology, being a novel and innovative approach has paved way to open up new perspective for the analysis of biomolecules, targeted drug delivery, protein or cells, clinical diagnosis, development of non-viral vectors for gene therapy, as transport vehicle for DNA, disease therapeutics etc. The current and potential use of nanotechnology would show the way to progression of smart and high performing fish. The comparative evaluation of extremely sophisticated nanotechnology with conventional process engineering proposes new prospectus in technological developments for superior water and wastewater technology processes. Nanoparticles have comprehensive advantages for management of drugs as liberation of vaccines and therefore hold the assurance for civilized protection of farmed fish against disease-causing pathogens. This review article explores the present concerns of food security, climate change as well as sustainability that are explored by the researchers in the area of nanotechnology, development of marine produce, along with its preservation and aquaculture.