Chitosan/Sodium Dodecyl Sulfate Complexes for Microencapsulation of Vitamin E and Its Release Profile-Understanding the Effect of Anionic Surfactant

Physicochemical characterization and cytotoxicity assessment of sodium dodecyl sulfate (SDS) modified chitosan (SDSCS) before and after removal of aflatoxins (AFs) as a potential mycotoxin Binder

Aflatoxins in food and feed with prominent toxic effects have jeopardized public health for decades. This investigation intends to explore synthesized SDS-modified chitosan as new generation of binder for removal of aflatoxin using a straightforward ionic cross-linking approach. The primary objective of this technique was to enhance affinity and adsorption capability of SDSCS towards aflatoxins. In this context, physicochemical properties of SDSCS characterized with advanced analytical techniques such as scanning electron microscope (SEM) coupled with energy dispersive X-ray spectroscopy (EDS) and Fourier transform infrared spectroscopy (FT-IR) before and after removal of aflatoxin. In this study, effect of the pH on the adsorption of aflatoxins (6ppb) indicated that the increase in SDSCS concentration from low (0.5) to high (2 %) resulted in an increase of about 80 %, 78 % and 81 % in the adsorption percentage of AFB1, AFG1, and AFB2 & AFG2, respectively. FT-IR analysis showed the intramolecular interactions of the amine groups of chitosan and sulfate group of SDS formed a stable complex in the removal of aflatoxin that verified with appearance of three new additional peaks at 1323.50, 984.34 and 603.42 cm-1. Notably, SEM images revealed that the porous SDSCS network was filled with aflatoxin molecules supported with EDS findings. Also, in vitro cytotoxicity assessments demonstrated that SDSCS protected HepG2 cells against cytotoxic effect caused by aflatoxin (5 µM) in a concentration-dependent manner compared to the control (p<0.01). Collectively, the adsorption mechanism may involve attraction of anionic aflatoxin molecule into the interconnected pores of SDSCS complex with numerous cationic active site via hydrogen bond and van der waals force.

Advancements in emulsion systems for specialized infant formulas: Research process and formulation proposals for optimizing bioavailability of nutraceuticals

With the rapid advancements in nutrition and dietary management, infant formulas for special medical purposes (IFSMPs) have been developed to cater to the unique nutraceutical requirements of infants with specific medical conditions or physiological features. However, there are various challenges in effectively preserving and maximizing the health benefits of the specific nutraceuticals incorporated in IFSMPs. This review provides an overview of the nutritional compositions of various IFSMPs and highlights the challenges associated with the effective supplementation of specific nutraceuticals for infants. In addition, it emphasizes the promising potential of emulsion delivery systems, which possess both encapsulation and delivery features, to significantly improve the solubility, stability, oral acceptance, and bioavailability (BA) of nutraceutical bioactives. Based on this information, this work proposes detailed strategies for designing and developing model IFSMP emulsions to enhance the BA of specially required nutraceuticals. Key areas covered include emulsion stabilization, selective release mechanisms, and effective absorption of nutraceuticals. By following these proposals, researchers and industry professionals can design and optimize emulsion-based IFSMPs with enhanced health benefits. This review not only outlines the developmental states of IFSMP formulations but also identifies future research directions aimed at improving the physiological health benefits of IFSMPs. This effort lays the theoretical groundwork for the further development of emulsion-type IFSMP in infant formula (IF) industry, positioning the IF industry to better meet the complex needs of infants requiring specialized nutrition.

Fungi-derived Chitosan-CTAB composite-based electrode for electrochemical simultaneous detection of Cd (II) and Pb (II)

Organic polymers have found diverse applications in the industrial and scientific world. One such application is using chitosan-based electrochemical sensors, which have gained rapid popularity due to their unique properties. To further enhance the material's porosity and adsorption capacity, the incorporation of a surfactant into the film has been explored. This study focuses on a rarely investigated combination of fungi-derived chitosan and cationic surfactant N-Cetyl-N, N, N-trimethyl-ammonium bromide (CTAB). The resultant composite was transformed into a thin film on the surface of a graphite electrode, by drop casting method, followed by curing at 65 °C hot air. The low-cost sensor thus obtained was characterized by electrochemical studies, and surface study techniques including AFM, SEM, and XPS. The results showed the properties of the film were strongly governed by the ratio of components in the composite. Under optimal conditions, the affinity for composite film increased 3 to 4 folds for Pb and Cd. The developed electrochemical sensors had a limit of detection of 0.317 μM and 0.572 μM for Pb and Cd respectively. The linear range of detection was found to be 1 × 10-6 M to 1.2 × 10-4 M for Pb (II) and 2 × 10-6 M to 1.4 × 10-4 M for Cd (II).

Coacervating behavior of amino acid anionic and amphoteric mixed micelle-polymer

In this paper, coacervates were formed with mixed micelles consisting of the anionic amino acid surfactant sodium lauroylsarcosinate (NLS) and amphoteric surfactant cocamidopropyl betaine (CAPB) in combination with cationic guar gum. Based on personal care formulation studies, coacervates were prepared by diluting a concentrated system with water to better suit the product application process. The phase behavior during dilution was revealed by turbidity, which was influenced by the mixed micelle ratio (X), salt concentration, and dilution ratio (R). Optical microscopy, cryo-SEM, SAXS and rotational rheometry were used to characterize the structure and properties of the coacervates, which strongly depended on the interaction strength between the polymer and micelles. Dominated by electrostatic interactions, the coacervates exhibited a dense porous structure with low water content and a high viscoelastic modulus, while weakened interactions resulted in a looser mesh internal structure with lower viscoelasticity, enhancing skin adsorption. These findings enhance our understanding of polymer-mixed micelle systems and offer practical strategies for controlling the properties of coacervates.

Molecular interaction of lysozyme with therapeutic drug azithromycin: Effect of sodium dodecyl sulfate on binding profile

This paper describes an inclusive biophysical study elucidating the interaction of therapeutic drug azithromycin (Azith) with hen egg white lysozyme (HEWL). Spectroscopic and computational tools have been employed to study the interaction of Azith with HEWL at pH 7.4. The fluorescence quenching constant values (Ksv) exhibited a decrease with the increase in temperature which revealed the occurrence of static quenching mechanism between Azith and HEWL. The thermodynamic data demonstrated that hydrophobic interactions were predominantly involved in the Azith-HEWL interaction. The negative value of standard Gibbs free energy (ΔG°) stated that the Azith-HEWL complex formed via spontaneous molecular interactions. The effect of sodium dodecyl sulfate (SDS) surfactant monomers on the binding propensity of Azith with HEWL was insignificant at lower concentrations however the binding significantly decreased at increased concentrations of the former. Far-UV CD data revealed alteration in the secondary structure of HEWL in the presence of Azith and the overall HEWL conformation changed. Molecular docking results revealed that the binding of Azith with HEWL takes place through hydrophobic interactions and hydrogen bonds.

Ultrasound-Assisted Encapsulation of Citronella Oil in Alginate/Carrageenan Beads: Characterization and Kinetic Models

The objective of this research was to investigate the effect of ultrasonication on citronella oil encapsulation using alginate/carrageenan (Alg/Carr) in the presence of sodium dodecyl sulfate (SDS). The functional groups of microparticles were characterized using Fourier transform infrared spectroscopy (FTIR), and the beads’ morphologies were observed using a scanning electron microscope (SEM). The FTIR results showed that the ultrasonication process caused the C-H bonds (1426 cm−1) to break down, resulting in polymer degradation. The SEM results showed that the ultrasonication caused the presence of cavities or pores in the cracked wall and a decrease in the beads’ size. In this study, the use of ultrasound during the encapsulation of citronella oil in Alg/Carr enhanced the encapsulation efficiency up to 95–97%. The kinetic evaluation of the oil release of the beads treated with ultrasound (UTS) showed a higher k1 value of the Ritger–Peppas model than that without ultrasonication (non-UTS), indicating that the oil release rate from the beads was faster. The R/F value from the Peppas–Sahlin model of the beads treated with UTS was smaller than that of the non-UTS model, revealing that the release of bioactive compounds from the UTS-treated beads was diffusion-controlled rather than due to a relaxation mechanism. This study suggests the potential utilization of UTS for controlling the bioactive compound release rate.

Electrospraying of Bio-Based Chitosan Microcapsules Using Novel Mixed Cross-Linker: Experimental and Response Surface Methodology Optimization

Chitosan microcapsules draw attention due to their biodegradability, biocompatibility, antibacterial behavior, low cost, easy processing, and the capability to be used for different applications. This study utilized the electrospraying technique for the chitosan microcapsules formulation. As a novel cross-linking agent, a mixture of oxalic acid and sodium phosphate dibasic was utilized as a collecting solution for the first time in the electrospraying of chitosan microcapsules. Scanning Electron Microscopy (SEM) was utilized to optimize the spherical morphology and size of the experimentally obtained microcapsules. The different parameters, including chitosan concentration, applied voltage, flow rate, and tip-to-collector (TTC) distance, affecting the microcapsules' size, sphericity, yield, and combined effects were optimized using Surface Responses Methodology (RSM). The Analysis of Variance (ANOVA) was utilized to obtain the impact of each parameter on the process responses. Accordingly, the results illustrated the significant impact of the voltage parameter, with the highest F-values and least p-values, on the capsule size, sphericity, and yield. The predicted optimum conditions were determined as 5 wt% chitosan concentration, 7 mL/h flow rate, 22 kV, and 8 cm TTC distance. The predicted responses at the optimized conditions are 389 µm, 0.72, and 80.6% for the capsule size, sphericity, and yield, respectively. While the validation of the model prediction was conducted experimentally, the obtained results were 369.2 ± 23.5 µm, 0.75 ± 0.04, and 87.3 ± 11.4%, respectively. The optimization process was successfully examined for the chitosan microcapsules manufacturing.

Modeling of in vitro drug release from polymeric microparticle carriers

Incorporation of active substances in polymeric microparticles (microencapsulation) is an important technological strategy used in the pharmaceutical industry to improve the functionality, quality, safety and/or therapeutic efficiency of pharmaceutical preparations for different routes of administration. The current focus of research in this field is on the encapsulation of small molecules and macromolecules into microparticles based on biocompatible synthetic polymers and biopolymers, such as polypeptides and polysaccharides, in order to achieve preferable drug release kinetics and many other advantages. Diversity in the structure and size of microparticles, choice of polymers, and manufacturing processes, allows for designing a multitude of microcarriers (e.g., monolithic matrix microspheres, hollow microcapsules, water-or oil-core microcapsules, stimulus-sensitive microcapsules), whereby their impact on biopharmaceutical profile of drugs can be manipulated. The results so far indicate that the in vitro drug release kinetics evaluation is one of the key aspects of the microparticle-type carrier characterization, where the application of the mathematical analysis (modeling) of the drug release profiles is an important tool for elucidating drug release mechanisms, as well as for evaluating the influence and optimization of formulation and process parameters in the microencapsulation procedure. The article reviews representative studies in which mathematical modeling of experimentally obtained release data was performed for microencapsulated model drugs with different physicochemical properties, as well as the relevance and potential limitations of this approach.