Elaboration of microparticles by the complex coacervation: Electro-kinetic study of associative mixtures and application to the encapsulation of an antalgic active ingredient

Study of β-lactoglobulin/acacia gum complex coacervation by diffusing-wave spectroscopy and confocal scanning laser microscopy

Microencapsulation of vitamin E by gelatin-high/low methoxy pectin complex coacervates: Effect of pH, pectin type, and protein/polysaccharide ratio

Influence of main whey protein components on the mechanism of complex coacervation with Acacia gum

The phase behavior of aqueous mixtures of fish gelatin (FG) and sodium alginate (SA) and complex coacervation phenomena depending on pH, ionic strength, and cation type (Na+, Ca2+) were studied by turbidimetric acid titration, UV spectrophotometry, dynamic light scattering, transmission electron microscopy and scanning electron microscopy for different mass ratios of sodium alginate and gelatin (Z = 0.01-1.00). The boundary pH values determining the formation and dissociation of SA-FG complexes were measured, and we found that the formation of soluble SA-FG complexes occurs in the transition from neutral (pHc) to acidic (pHφ1) conditions. Insoluble complexes formed below pHφ1 separate into distinct phases, and the phenomenon of complex coacervation is thus observed. Formation of the highest number of insoluble SA-FG complexes, based on the value of the absorption maximum, is observed at рHopt and results from strong electrostatic interactions. Then, visible aggregation occurs, and dissociation of the complexes is observed when the next boundary, pHφ2, is reached. As Z increases in the range of SA-FG mass ratios from 0.01 to 1.00, the boundary values of рНc, рHφ1, рHopt, and рHφ2 become more acidic, shifting from 7.0 to 4.6, from 6.8 to 4.3, from 6.6 to 2.8, and from 6.0 to 2.7, respectively. An increase in ionic strength leads to suppression of the electrostatic interaction between the FG and SA molecules, and no complex coacervation is observed at NaCl and CaCl2 concentrations of 50 to 200 mM.

Complex coacervation between β-lactoglobulin and acacia gum in aqueous medium

A gelatin and sodium alginate complex coacervation system was studied and an effect of pH and colloid mixing ratios on coacervation was investigated. A colloid mixing ratio at which optimum coacervation occurred varied with the coacervation pH. Viscometric, turbidity and coacervate dry yield investigations were used to investigate optimum conditions for complex coacervation. Optimum coacervation occurred at pH 3.5 at a gelatin sodium alginate ratio 4:1. Coacervate and equilibrium fluid was analyzed for gelatin and sodium alginate contents and yields calculated on the basis of chemical analysis showed that optimum coacervation occurred at 25% sodium alginate fraction at pH 3.5.

Orange essential oil was microencapsulated by complex coacervation with whey protein isolate (WPI): carboxymethylcellulose (CMC), WPI:sodium alginate (SA) and WPI:chitosan (CH). Effect of pH, protein:polysaccharide ratio and solid concentration on coacervation efficiency were selected for the best coacervation conditions. Tannic acid (TA), sodium tripolyphosphate, oxidised tannic acid and transglutaminase enzyme (TG) were used as cross-linking agents. Highest encapsulation efficiency (EE) for wet coacervated microcapsules ranged from 88% to 94%. Microcapsules were freeze and spray dried to evaluate their effect on its integrity. EE was higher than 80% in freeze dried coacervated microcapsules with and without cross-linking agent, but they formed a solid cake. Spray-dried samples formed a free fluid solid (10–20 µm), where the systems WPI:CMC and WPI:CH cross-linked with TA and TG, respectively showed the highest EE (47% and 50% respectively), representing 400% improvement compared to the samples without cross-linking.

Combination of sodium alginate with tilapia fish gelatin for improved texture properties and nanostructure modification

Characterization of a novel complex coacervate based on whey protein isolate-tamarind seed mucilage

Preparation and study of digestion behavior of lactoferrin-sodium alginate complex coacervates

BackgroundThe electrostatic interactions between polysaccharides and proteins are an interesting field in the complex coacervation. PH and mixing ratio have major effect on the complexation and the coacervates structure. Hence, it is necessary to find the optimum pH and mixing ratio of the coacervates as well as understanding the thermal, mechanical, and structural characterization of the coacervates. Thus, structural changes of the complexes of sodium caseinate (NaCas) and high methoxyl pectin as a function of pH (2.00–7.00), biopolymer ratios (1:1, 2:1, 4:1, and 8:1), and total biopolymer concentration (0.1, 0.2, and 0.4% w/v) were evaluated by light scattering and ζ-potential measurements. The phase separation behavior of the NaCas/HMP coacervate and its kinetics turbidity were also investigated via monitoring the turbidity profiles. Moreover, the thermal, rheological and structural behavior of the coacervates was evaluated at the selected pH values.ResultsThe highest turbidity, particle size, and viscosity were achieved at pHmax = 3.30 and formation or dissociation around the pHmax was confirmed by particle size and FTIR. The optimum condition for the coacervation of NaCas and HMP was obtained at ratio 4:1 and 0.4% w/v. Thermal and mechanical stability of the NaCas/HMP coacervates was improved at pH 3.30. By increasing the total concentration of biopolymers, the NaCas/pectin ratio shifted to higher pH values. Furthermore, the maximum coacervate yield was achieved at 39.8% w/w at a ratio of 4:1 of NaCas/HMP and a total biopolymer concentration of 0.4% w/v.ConclusionPhase separation behavior of the coacervates exhibited the optimum pH in coacervation between NaCas and HMP. Furthermore, the rheological, thermal and structural stability of the coacervates were improved in comparison with the single biopolymers.Graphical

The effect of microencapsulation of microbial oil containing CLA by the complex coacervation on the physicochemical and sensory characteristics of buttermilk

There is a negative dynamic of the spread of cerebrovascular diseases, which often lead to disability or death in patients in the world, today. Such diseases are characterized by acute disorders of cerebral metabolism and blood circulation, against the background of other chronic pathologies. More than one hundred thousand cases of stroke are registered in Ukraine every year, with more than thirty percent of patients dying within the first month of the disease according to the Center for Medical Statistics of the Ministry of Health of Ukraine. The nasal route of administration is a promising method of transporting active substances for systemic action, various pharmacotherapeutic groups, both small and large molecules. The created nasal preparations of hormones, antibiotics, analgesics, exhibit a quick therapeutic effect due to the branched capillary system in the nasal cavity. In addition, the nasal route of administration is the most promising non-invasive method for delivering active substances to the brain for cerebroprotective drugs, due to the anatomical features of the location of the nerves. According to published data, the researchers found that the receptor antagonist of interleukin-1 (IL-1ra) exhibits neuroprotective properties in brain ischemia by blocking excess IL-1 and activating the anti-inflammatory cytokine cascade, in order to reduce local inflammation and neuronal loss. Therefore, in order to expand the range of pharmacotherapeutic drugs – neuroprotectors, the development of a new intranasal form with the active pharmaceutical ingredient - receptor antagonist interleukin-1 (IL-1ra) is an urgent problem of modern medicine and pharmacy. The aim of work was to substantiate the choice of excipients for the new intranasal gel of the receptor antagonist of interleukin-1 (IL-1ra). Materials and methods. The studies were carried out according to the plan of two-way analysis of variance with repeated observations. Factors that were investigated: factor A (type of polymer) – A1 – chitosan 3 %, A2 – sodium carboxymethyl cellulose 0.3 %, A3 – sodium hyaluronate 0.7 %, A4 – sodium alginate 0.5 %; factor B (type of alcohol): B1 – without alcohol, B2 – sorbitol, B3 – glycerin, B4 – D-panthenol. A prefabricated solution of the receptor antagonist of interleukin-1 (IL-1ra) was used as an active substance. A portion of the active substance was taken considering the calculations, to ensure a concentration of 0.5 % IL-1ra in each composition. The release of the active pharmaceutical ingredient was determined by equilibrium dialysis according to Kruvchinsky at 37.0 ± 0.5 °C through a semi-permeable membrane – “Cuprofan” for all compositions. Dialysis was performed in Franz cells at a nine-position station (PermeGear, Inc., USA). The concentration of IL-1ra, after 30 minutes, was determined by UV spectrophotometry at a wavelength of 280 nm on a UV-2600 spectrophotometer (Shimadzu Corporation, Japan). Results. We studied the effect of pharmaceutical factors (polymers and alcohols) on the intensity of the release of IL-1ra from the nasal form to justify the choice of excipients for the nasal gel of the receptor antagonist interleukin-1 β. The results of the analysis of variance of pharmaceutical factors (polymers and alcohols) showed that hydrophilic polymers and humectants had a significant effect on the release of the active substance from the experimental compositions. It is advisable to use a mucoadhesive polymer – sodium salt of carboxymethylcellulose, as well as alcohol-moisturizer D-panthenol for the new nasal form of IL-1ra, as excipients. Conclusions . Excipients were selected for a liquid intranasal gel with the receptor antagonist interleukin-1 (IL-1ra). It was found that the type of mucoadhesive polymers and alcohols, to moisten the mucous membrane, had a significant effect on the release of the active pharmaceutical ingredient from nasal dosage forms. As a result of research, it was found that the optimal release of IL-1ra from nasal compositions was provided by excipients - hydrophilic mucoadhesive component - sodium carboxymethylcellulose with the addition of humectant alcohol – D-panthenol.

Interaction of gelatin and sodium alginate in an aqueous medium

Microencapsulation of green coffee oil by complex coacervation of soy protein isolate, sodium casinate and polysaccharides: Physicochemical properties, structural characterisation, and oxidation stability