Pluronics modified liposomes for curcumin encapsulation: Sustained release, stability and bioaccessibility

Multifaceted role of phyto-derived polyphenols in nanodrug delivery systems

As naturally occurring bioactive products, several lines of evidence have shown the potential of polyphenols in the medical intervention of various diseases, including tumors, inflammatory diseases, and cardiovascular diseases. Notably, owing to the particular molecular structure, polyphenols can combine with proteins, metal ions, polymers, and nucleic acids providing better strategies for polyphenol-delivery strategies. This contributes to the inherent advantages of polyphenols as important functional components for other drug delivery strategies, e.g., protecting nanodrugs from oxidation as a protective layer, improving the physicochemical properties of carbohydrate polymer carriers, or being used to synthesize innovative functional delivery vehicles. Polyphenols have emerged as a multifaceted player in novel drug delivery systems, both as therapeutic agents delivered to intervene in disease progression and as essential components of drug carriers. Although an increasing number of studies have focused on polyphenol-based nanodrug delivery including epigallocatechin-3-gallate, curcumin, resveratrol, tannic acid, and polyphenol-related innovative preparations, these molecules are not without inherent shortcomings. The active biochemical characteristics of polyphenols constitute a prerequisite to their high-frequency use in drug delivery systems and likewise to provoke new challenges for the design and development of novel polyphenol drug delivery systems of improved efficacies. In this review, we focus on both the targeted delivery of polyphenols and the application of polyphenols as components of drug delivery carriers, and comprehensively elaborate on the application of polyphenols in new types of drug delivery systems. According to the different roles played by polyphenols in innovative drug delivery strategies, potential limitations and risks are discussed in detail including the influences on the physical and chemical properties of nanodrug delivery systems, and their influence on normal physiological functions inside the organism.

Selective antibacterial activities and storage stability of curcumin-loaded nanoliposomes prepared from bovine milk phospholipid and cholesterol

Present study prepared curcumin-loaded nanoliposomes using bovine milk, krill phospholipids and cholesterol; and investigated the effects of cholesterol on membrane characteristics, storage stability and antibacterial properties of the curcumin nanoliposomes. Bovine milk phospholipids which have higher saturation than krill phospholipids resulted in formation of curcumin-loaded nanoliposomes with higher encapsulation efficiency (84.78%), larger absolute value of zeta potential and vesicle size (size: 159.15 ± 5.27 nm, zeta potential: -28.3 ± 0.62 mV). Cholesterol helps to formation of a more hydrophobic, compact and tighter bilayer membrane structure which improved the storage stability of nanoliposomes under alkaline (66.25 ± 0.46%), heat (43.25 ± 0.69%) and sunlight (49.44 ± 1.78%) conditions. In addition, curcumin-loaded nanoliposomes can effectively target infectious bacteria which secrete pore-forming toxins such as Staphylococcus aureus by causing the bacterial cell wall to lysis. Findings from present work can guide future development of novel antibacterial agents for use in food preservation.

Prolonged anesthesia and decreased toxicity of enantiomeric-excess bupivacaine loaded in ionic gradient liposomes

Bupivacaine is the most employed local anesthetic in surgical procedures, worldwide. Its systemic toxicity has directed the synthesis of the less toxic, S(-) enantiomer. This work describes a formulation of ionic gradient liposomes (IGL) containing _S75BVC, an enantiomeric excess mixture of 75% S(-) and 25% R(+) bupivacaine. IGL prepared with 250 mM (NH₄)₂SO₄ in the inner aqueous core of phosphatidylcholine and cholesterol (3:2 mol%) vesicles plus 0.5% _S75BVC showed average sizes of 312.5 ± 4.5 nm, low polydispersity (PDI < 0.18), negative zeta potentials (-14.2 ± 0.2 mV) and were stable for 360 days. The encapsulation efficiency achieved with IGL_S75BVC (%EE = 38.6%) was higher than with IGL prepared with racemic bupivacaine (IGL_RBVC, %EE = 28.3%). TEM images revealed spherical vesicles and µDSC analysis provided evidence on the interaction of the anesthetic with the lipid bilayer. Then, in vitro - release kinetics and cytotoxicity- and in vivo - toxic effects in Zebrafish and biochemical/histopathological analysis plus analgesia in Wistar rats - tests were performed. IGL_S75BVC exhibited negligible toxicity against Schwann cells and Zebrafish larvae, and it did not affect biochemical markers or the morphology of rat tissues (heart, brain, cerebellum, sciatic nerve). The in vitro release of _S75BVC from IGL was extended from 4 to 24 h, justifying the prolonged anesthetic effect measured in rats (~9 h). The advantages of IGL_S75BVC formulation over IGL_RBVC and plain bupivacaine formulations (prolonged anesthesia, preferential sensorial blockade, and no toxicity) confirm its potential for clinical use in surgical anesthesia.

Nanoliposomes for encapsulation and calcium delivery of egg white peptide-calcium complex

Nanoliposomes and crude liposomes loaded with egg white peptide-calcium complex (EWP-Ca) were fabricated by thin-film dispersion with or without dynamic high-pressure microfluidization. Their physiochemical properties, in vitro stability, and calcium release profiles were investigated in this study. Results showed that the EWP-Ca-loaded nanoliposomes exhibited spherical structures with a lower particle size and polydispersity index as well as a higher thermal stability as compared to the corresponding crude liposomes. Further investigations revealed that EWP-Ca was embedded into the liposomes mainly through hydrogen bonding and present in an amorphous form within the liposomes. Additionally, the EWP-Ca-loaded nanoliposomes effectively slowed the release of calcium in gastric digestion, allowing more soluble calcium to enter the intestinal tract; in the subsequent intestinal digestion, the EWP-Ca-loaded nanoliposomes were more electrically and physically stable than the crude liposomes. Therefore, the EWP-Ca-loaded nanoliposomes could be used as a favorable dietary calcium delivery system to promote calcium bioavailability. PRACTICAL APPLICATION: Nanoliposomes were fabricated in this study to encapsulate the egg white peptide-calcium complex (EWP-Ca) for calcium delivery. The EWP-Ca-loaded nanoliposomes effectively slowed the release of calcium in gastric digestion, allowing more soluble calcium to enter the intestinal tract, and were more electrically and physically stable in the subsequent intestinal digestion. Therefore, the EWP-Ca-loaded nanoliposomes may be incorporated in calcium-fortified food to enhance calcium delivery for maintaining bone health.

Build-Up of a 3D Organogel Network within the Bilayer Shell of Nanoliposomes. A Novel Delivery System for Vitamin D3: Preparation, Characterization, and Physicochemical Stability

The inherent thermodynamic instability of liposomes during production and storage has limited their widespread applications. Therefore, a novel structure of food-grade nanoliposomes stabilized by a 3D organogel network within the bilayer shell was developed through the extrusion process and successfully applied to encapsulate vitamin D₃. A huge flocculation and a significant reduction of zeta potential (-17 mV) were observed in control nanoliposomes (without the organogel shell) after 2 months of storage at 4 °C, while the sample with a gelled bilayer showed excellent stability with a particle diameter of 105 nm and a high negative zeta potential (-63.4 mV), even after 3 months. The development of spherical vesicles was confirmed by TEM. Interestingly, the gelled bilayer shell led to improved stability against osmotically active divalent salt ions. Electron paramagnetic resonance confirmed the higher rigidity of the shell bilayer upon gelation. The novel liposome offered a dramatic increase in encapsulation efficiency and loading of vitamin D₃ compared to those of control.

Manufacturing micro/nano chitosan/chondroitin sulfate curcumin-loaded hydrogel in ionic liquid: A new biomaterial effective against cancer cells

Chitosan/chondroitin sulfate (CHT/CS) curcumin-charged hydrogels were prepared through polyelectrolytic complexation (PEC) following two methodologies (PEC-CUR and PEC-T-CUR) and were applied on apoptosis of HeLa, HT29 and PC3 cancer cells. PEC-T-CUR (ionic liquid (IL) mixed using ultraturrax homogenizer) results show to be far better than for PEC-CUR (IL mixed using magnetic stirring), with IC₅₀ being improved 5.13 times to HeLa cancer cells (from 1675.2 to 326.7 μg mL^-1). PECs produced by this methodology presented favorable characteristics, such as particle size, hydrophobicity, pH swelling. Beyond this, the IL was quantitatively recovered in both cases. CUR entrapment levels were hugely loaded into PEC at around 100%. Swelling, dissolution/degradation, and pH_pzc assays showed that PECs may positively act in several environments, releasing the CUR, the CHT and CS as well. Characterization through FTIR, SEM, TEM, TGA, DSC, and WAXS confirmed CUR presence in both types of PECs, and cytotoxic studies showed the significant anticancer effects of CUR-containing PECs.

Progresses in Food Packaging, Food Quality, and Safety-Controlled-Release Antioxidant and/or Antimicrobial Packaging

Food packaging is designed to protect foods, to provide required information about the food, and to make food handling convenient for distribution to consumers. Packaging has a crucial role in the process of food quality, safety, and shelf-life extension. Possible interactions between food and packaging are important in what is concerning food quality and safety. This review tries to offer a picture of the most important types of active packaging emphasizing the controlled/target release antimicrobial and/or antioxidant packaging including system design, different methods of polymer matrix modification, and processing. The testing methods for the appreciation of the performance of active food packaging, as well as mechanisms and kinetics implied in active compounds release, are summarized. During the last years, many fast advancements in packaging technology appeared, including intelligent or smart packaging (IOSP), (i.e., time-temperature indicators (TTIs), gas indicators, radiofrequency identification (RFID), and others). Legislation is also discussed.

The Formation of Chitosan-Coated Rhamnolipid Liposomes Containing Curcumin: Stability and In Vitro Digestion

There is growing interest in developing biomaterial-coated liposome delivery systems to improve the stability and bioavailability of curcumin, which is a hydrophobic nutraceutical claimed to have several health benefits. The curcumin-loaded rhamnolipid liposomes (Cur-RL-Lips) were fabricated from rhamnolipid and phospholipids, and then chitosan (CS) covered the surface of Cur-RL-Lips by electrostatic interaction to form CS-coated Cur-RL-Lips. The influence of CS concentration on the physical stability and digestion of the liposomes was investigated. The CS-coated Cur-RL-Lips with RL:CS = 1:1 have a relatively small size (412.9 nm) and positive charge (19.7 mV). The CS-coated Cur-RL-Lips remained stable from pH 2 to 5 at room temperature and can effectively slow the degradation of curcumin at 80 °C; however, they were highly unstable to salt addition. In addition, compared with Cur-RL-Lips, the bioavailability of curcumin in CS-coated Cur-RL-Lips was relatively high due to its high transformation in gastrointestinal tract. These results may facilitate the design of a more efficacious liposomal delivery system that enhances the stability and bioavailability of curcumin in nutraceutical-loaded functional foods and beverages.

Oral Nano Drug Delivery Systems for the Treatment of Type 2 Diabetes Mellitus: An Available Administration Strategy for Antidiabetic Phytocompounds

In view of the worldwide serious health threat of type 2 diabetes mellitus (T2DM), natural sources of chemotherapies have been corroborated as the promising alternatives, with the excellent antidiabetic activities, bio-safety, and more cost-effective properties. However, their clinical application is somewhat limited, because of the poor solubility, instability in the gastrointestinal tract (GIT), low bioavailability, and so on. Nowadays, to develop nanoscaled systems has become a prominent strategy to improve the drug delivery of phytochemicals. In this review, we primarily summarized the intervention mechanisms of phytocompounds against T2DM and presented the recent advances in various nanosystems of antidiabetic phytocompounds. Selected nanosystems were grouped depending on their classification and structures, including polymeric NPs, lipid-based nanosystems, vesicular systems, inorganic nanocarriers, and so on. Based on this review, the state-of-the-art nanosystems for phytocompounds in T2DM treatment have been presented, suggesting the preponderance and potential of nanotechnologies.

Potential of Nanonutraceuticals in Increasing Immunity

Nutraceuticals are defined as foods or their extracts that have a demonstrably positive effect on human health. According to the decision of the European Food Safety Authority, this positive effect, the so-called health claim, must be clearly demonstrated best by performed tests. Nutraceuticals include dietary supplements and functional foods. These special foods thus affect human health and can positively affect the immune system and strengthen it even in these turbulent times, when the human population is exposed to the COVID-19 pandemic. Many of these special foods are supplemented with nanoparticles of active substances or processed into nanoformulations. The benefits of nanoparticles in this case include enhanced bioavailability, controlled release, and increased stability. Lipid-based delivery systems and the encapsulation of nutraceuticals are mainly used for the enrichment of food products with these health-promoting compounds. This contribution summarizes the current state of the research and development of effective nanonutraceuticals influencing the body's immune responses, such as vitamins (C, D, E, B12, folic acid), minerals (Zn, Fe, Se), antioxidants (carotenoids, coenzyme Q10, polyphenols, curcumin), omega-3 fatty acids, and probiotics.

Modeling the release of food bioactive ingredients from carriers/nanocarriers by the empirical, semiempirical, and mechanistic models

The encapsulation process has been utilized in the field of food technology to enhance the technofunctional properties of food products and the delivery of nutraceutical ingredients via food into the human body. The latter application is very similar to drug delivery systems. The inherent sophisticated nature of release mechanisms requires the utilization of mathematical equations and statistics to predict the release behavior during the time. The science of mathematical modeling of controlled release has gained a tremendous advancement in drug delivery in recent years. Many of these modeling methods could be transferred to food. In order to develop and design enhanced food controlled/targeted bioactive release systems, understanding of the underlying physiological and chemical processes, mechanisms, and principles of release and applying the knowledge gained in the pharmaceutical field to food products is a big challenge. Ideally, by using an appropriate mathematical model, the formulation parameters could be predicted to achieve a specific release behavior. So, designing new products could be optimized. Many papers are dealing with encapsulation approaches and evaluation of the impact of process and the utilized system on release characteristics of encapsulated food bioactives, but still, there is no deep insight into the mathematical release modeling of encapsulated food materials. In this study, information gained from the pharmaceutical field is collected and discussed to investigate the probable application in the food industry.

Preparation and characterization of curcumin solid dispersion using HPMC

Curcumin solid dispersions were prepared using hydroxypropyl methylcellulose (HPMC) to enhance water solubility of curcumin. The particle size of curcumin solid dispersions was in range from 371 to 528 nm and particles were shaped as spherical with wrinkles. The encapsulation efficiency was over 93% for all samples, and water solubility of curcumin was significantly improved to 238 µg/mL when the ratio of curcumin to HPMC was 20:80. The results of X-ray diffraction, differential scanning calorimeter, and Fourier transform infrared spectroscopy showed that crystalline form of curcumin changed to amorphous form. Curcumin solid dispersions showed improved dissolution behavior compared to pure curcumin and the curcumin release kinetic studies were applied to find best-fitting model. This study showed a great potential of solid dispersion using HPMC as curcumin delivery system with improved water solubility and oral absorption. PRACTICAL APPLICATION: Curcumin has limited applications in the food industry because of low water solubility. Dongoh water-soluble curcumin (DW-CURs) were prepared by solid dispersion method with HPMC. Our results indicated that curcumin solid dispersions improved the water solubility of curcumin and showed a sustained release, demonstrating its possibility of body application. Therefore, DW-CURs are a promising formulation for application as a functional ingredient in the food industry.

RGD peptide-mediated liposomal curcumin targeted delivery to breast cancer cells

In this study, turmeric's active ingredient (Curcumin) was encapsulated into RGD modified Liposomes (RGD-Lip-Cur) its cytotoxic effect on the breast cancer cell line (MCF-7) was evaluated by MTT, flow cytometry and Caspase assay. Liposomes were characterized using transmission electron microscopy (TEM). Results demonstrated that the liposomes were spherical in shape, ranging from 70 to 100 nm. MTT assay revealed that RGD-Lip-Cur had a significant cytotoxic effect on MCF-7 cells at concentrations of 32, 16 and 4 μg/ml compared to Lip-Cur (P < 0.05) and curcumin (P < 0.01). The apoptosis assay demonstrated that RGD-Lip-Cur induces the apoptosis in MCF-7 cells (39.6% vs 40.2% for initial and secondary apoptosis) significantly more than Lip-Cur (67.7% vs 9.16% for initial and secondary apoptosis) and free curcumin (7.84% vs 38.8% for initial and secondary apoptosis). Moreover, caspase assay showed that RGD-Lip-Cur activates caspase 3/7 compared to Lip-Cur (P < 0.05) and free curcumin (P < 0.01). The RGD-Lip-Cur was similar to the control group and had no significant cytotoxicity effect. It is concluded that RGD-Lip-Cur as a novel carrier have high cytotoxicity effect on breast cancer cell line (MCF-7).

Preparation and Evaluation of Stearylamine-Bearing Pemetrexed Disodium-Loaded Cationic Liposomes In Vitro and In Vivo

Pemetrexed disodium (PMX) stands out in the treatment of non-small cell lung cancer (NSCLC), but with short half-life and toxic side effects. This study was to design cationic liposomes for targeting delivery PMX to the lungs. The PMX cationic liposome was prepared by thin-film hydration using stearylamine (SA) as the positive component of charge-regulating charge. Then, the PMX cationic liposome (SA-PMX-Lips) was characterized by particle size, morphology, entrapment efficiency (EE), and drug loading (DL). Finally, the drug release behavior in vitro, the pharmacokinetic study, and tissue distribution of SA-PMX-Lips were evaluated separately, with PMX solution (PMX-Sol) and PMX liposome (PMX-Lips) as the control. According to results, SA-PMX-Lips were spherical and the particle size was 219.7 ± 4.97 nm with a narrow polydispersity index (PDI) (0.231 ± 0.024) and a positive zeta potential 22.2 ± 0.52 mV. Its EE was 92.39 ± 1.94% and DL was 9.15 ± 0.07%. The results of in vitro and in vivo experiments showed that SA-PMX-Lips released slowly, prolonged retention time and increased the value of AUC. More notably, SA-PMX-Lips could improve the accumulation of drugs in the lungs and the relative uptake rate (Re) was 2.35 in the lungs, which indicated its lung targeting. In summary, SA-PMX-Lips showed the potential for the effective delivery of PMX and the treatment of NSCLC.

Nanostructured Lipid-Based Delivery Systems as a Strategy to Increase Functionality of Bioactive Compounds

Acquisition of a healthy lifestyle through diet has driven the food manufacturing industry to produce new food products with high nutritional quality. In this sense, consumption of bioactive compounds has been associated with a decreased risk of suffering chronic diseases. Nonetheless, due to their low solubility in aqueous matrices, high instability in food products during processing and preparation as well as poor bioavailability, the use of such compounds is sometimes limited. Recent advancements in encapsulation and protection of bioactive compounds has opened new possibilities for the development of novel food products. In this direction, the present review is attempting to describe encapsulation achievements, with special attention to nanostructured lipid-based delivery systems, i.e., nanoemulsions, multi-layer emulsions and liposomes. Functionality of bioactive compounds is directly associated with their bioavailability, which in turn is governed by several complex processes, including the passage through the gastrointestinal tract and transport to epithelial cells. Therefore, an overview of recent research on the properties of these nanostructured lipid-based delivery systems with a strong impact on the functionality of bioactive compounds will be also provided. Nanostructured lipid-based delivery systems might be used as a potential option to enhance the solubility, stability, absorption and, ultimately, functionality of bioactive compounds. Several studies have been performed in this line, modifying the composition of the nanostructures, such as the lipid-type or surfactants. Overall, influencing factors and strategies to improve the efficacy of encapsulated bioactive compounds within nanostructures have been successfully identified. This knowledge can be used to design effective targeted nanostructured lipid-based delivery systems for bioactive compounds. However, there is still a lack of information on food interactions, toxicity and long-term consumption of such nanostructures.

Novel folated pluronic F127 modified liposomes for delivery of curcumin: preparation, release, and cytotoxicity

Aim: A novel folated pluronic F127 (FA-F127) was synthesised, so as to modify liposomes with FA group on the surface, and evaluate the effects of FA-F127 modification on the properties of the modified liposomes.Methods: FA was linked to one end of pluronic F127, via the terminal OH group, to obtain FA-F127 and the structure was characterised. FA-F127 modified curcumin liposomes (cur-FA-F127-Lps) were prepared. The physicochemical characteristics of cur-FA-F127-Lps, including morphology and particle size, were studied. The in vitro cytotoxicity of cur-FA-F127-Lps against KB cancer cells was determined by MTT tests.Results: The effects of FA-F127 modification on the average particle size, PDI, curcumin encapsulation efficiency and microstructure were not significant. Compared with nonfolated F127 liposomes (cur-F127-Lps), cur-FA-F127-Lps exhibited significantly higher cytotoxicity towards KB cells.Conclusions: Folic acid modified liposomes provide a novel strategy to improve the chemotherapeutic efficacy of hydrophobic bioactive compounds.

Design, Synthesis and Characterization of a Novel Type of Thermo-Responsible Phospholipid Microcapsule-Alginate Composite Hydrogel for Drug Delivery

Liposomes are extensively used in drug delivery, while alginates are widely used in tissue engineering. However, liposomes are usually thermally unstable and drug-leaking when in liquids, while the drug carriers made of alginates show low loading capacities when used for drug delivery. Herein, we developed a type of thermo-responsible liposome-alginate composite hydrogel (TSPMAH) by grafting thermo-responsive liposomes onto alginates by using Ca2+ mediated bonding between the phosphatidic serine (PS) in the liposome membrane and the alginate. The temperature-sensitivity of the liposomes was actualized by using phospholipids comprising dipalmitoylphosphatidylcholine (DPPC) and PS and the liposomes were prepared by a thin-film dispersion method. The TSPMAH was then successfully prepared by bridge-linking the microcapsules onto the alginate hydrogel via PS-Ca2+-Carboxyl-alginate interaction. Characterizations of the TSPMAH were carried out using scanning electron microscopy, transform infrared spectroscopy, and laser scanning confocal microscopy, respectively. Their rheological property was also characterized by using a rheometer. Cytotoxicity evaluations of the TSPMAH showed that the composite hydrogel was biocompatible, safe, and non-toxic. Further, loading and thermos-inducible release of model drugs encapsulated by the TSPMAH as a drug carrier system was also studied by making protamine-siRNA complex-carrying TSPMAH drug carriers. Our results indicated that the TSPMAH described herein has great potentials to be further developed into an intelligent drug delivery system.

Solid-state properties, solubility, stability and dissolution behaviour of co-amorphous solid dispersions of baicalin

Formation of different baicalin co-former based solid dispersion formulations, which demonstrate improved solubility and dissolution performance.

Fabrication of OSA Starch/Chitosan Polysaccharide-Based High Internal Phase Emulsion via Altering Interfacial Behaviors

This paper attempted to construct a high internal phase emulsion (HIPE) through altering interfacial behaviors using the electrostatic interaction between positive chitosan and negative octenyl succinic anhydride (OSA) starch. The partial polysaccharide complex of OSA starch/chitosan was used to stabilize HIPE, which was able to adsorb at the oil droplet interface and prevent the coalescence of oil droplets. The wettability of OSA starch was enhanced with the addition of positively charged chitosan, leading to the formation of partial complexes. The impact of pH and concentration of chitosan on the droplet size, surface charge, and interface behavior were investigated, and the formation of the polysaccharide complex was further confirmed by atomic force microscopy. The presence of the OSA starch/chitosan complex facilitated the formation of stable HIPE with a gel-like structure and satisfactory centrifugal and oxidative stability. These results are useful to provide information for fabricating polysaccharide-based HIPE delivery systems, which may help expand their application in the food industry.

Improvement on stability, loading capacity and sustained release of rhamnolipids modified curcumin liposomes

A novel cholesterol-free curcumin delivery system was fabricated by rhamnolipids modified liposomes (RL-Lps). The incorporation of the rhamnolipids increased the sphericity, reduced the size, and decreased the polydispersity of the liposomes compared with pure liposomes (Lps). Analysis of the environmental stability of the RL-Lps showed they have good long-term stability over a wide range of pH (2-3 and 5-8), ionic strengths (0-200 mM), and accelerated centrifugal conditions. The curcumin-loaded rhamnolipids modified liposomes (Cur-RL-Lps) could be prepared with a relatively high loading efficiency (LE > 90%) and loading capacity (LC > 3.5%). The thermal and photochemical stability of the curcumin was improved after encapsulation in the Cur-RL-Lps. In vitro release studies indicated that the sustained release of the curcumin was prolonged when rhamnolipids were incorporated into the liposomes. This study shows that rhamnolipids have great potential for liposomal delivery system suitable for utilization in functional foods, dietary supplements, and pharmaceutical preparations.

Encapsulation of Lipophilic Polyphenols into Nanoliposomes Using pH-Driven Method: Advantages and Disadvantages

The poor water solubility and oral bioavailability of many lipophilic polyphenols can be improved through the use of colloidal delivery systems. In this study, a pH-driven method was used to encapsulate curcumin, quercetin, and resveratrol within nanoliposomes. This method is based on the decrease in water-solubility of certain polyphenols when they move from alkaline to acid conditions. However, the chemical stability of some polyphenols is relatively poor under alkaline conditions. For this reason, the impact of pH on the chemical degradation of the three polyphenols was studied. The polyphenols were then encapsulated within nanoliposomes using the pH-driven method and the encapsulation efficiency (EE) and chemical stability were determined. The EE of curcumin, quercetin, and resveratrol in the nanoliposomes was 100, 54, and 93%, respectively. Differences in the EE were mainly attributed to differences in their stability under alkaline conditions. Our results show that the application of this method to other lipophilic polyphenols depends on the impact of pH on their solubility and chemical stability, which needs to be established on a case-by-case basis.

Improved water dispersibility and photostability in folic acid nanoparticles with transglycosylated naringin using combined processes of wet-milling and freeze-drying

We successfully prepared folic acid (FA) nanoparticles with excellent dispersibility and photostability using a combination of bead milling and freeze-drying with transglycosylated naringin (Naringin-G), a newly developed transglycosylated food additive. Poly-vinyl pyrrolidon (PVP) was used for comparison with Naringin-G. Water dispersibility and photostability of the freeze-dried formulations were assessed. The dispersibility and physicochemical properties of nanoparticle formulations were evaluated using dynamic light scattering, powder X-ray diffraction (PXRD), and small-angle X-ray scattering (SAXS). Results indicated that the median particle size of FA in the slurry bead milled with Naringin-G decreased notably with time and fell below 100 nm after milling for 300 min. Further, FA nanoparticles with Naringin-G were stable without aggregation following re-dispersion of freeze-dried FA formulations in water. Contrarily, the addition of PVP did not prevent the aggregation of FA nanoparticles following re-dispersion of freeze-dried FA formulations. Solid structures of freeze-dried FA formulations with Naringin-G or PVP were assessed using PXRD and SAXS. PXRD patterns of all freeze-dried formulations highlighted broadening and weakening of peaks, indicating a decrease in FA crystallinity following bead milling, regardless of the additive concentration of Naringin-G and PVP. The scattering intensity profiles of FA formulations with PVP dramatically decreased after milling, whereas FA formulations with Naringin-G did not exhibit changes in SAXS patterns. FA formulations with Naringin-G registered faster enhancement in release rate than PVP in pH 1.2 buffer solutions. The release rate of freeze-dried FA formulation with Naringin-G exhibited at least five-fold enhancement when compared to untreated FA. FA formulation with Naringin-G was stable to photodegradation under fluorescent light. Naringin-G prevented photodegradation of FA due to its antioxidant effect and scavenged radicals. These findings indicated that freeze-dried FA formulation with Naringin-G can improve its water-dispersibility and photodegradation due to the effectiveness of Naringin-G as a dispersant and cryoprotectant.

Liver-targeted liposomes for codelivery of curcumin and combretastatin A4 phosphate: preparation, characterization, and antitumor effects

Background

Recent efforts have been focused on combining two or more therapeutic approaches with different mechanisms to enhance antitumor therapy. Moreover, nanosize drug-delivery systems for codelivering two drugs with proapoptotic and antiangiogenic activities have exhibited great potential in efficient treatment of cancers.

Methods

Glycyrrhetinic acid (GA)–modified liposomes (GA LPs) for liver-targeted codelivery of curcumin (Cur) and combretastatin A4 phosphate (CA4P) were prepared and characterized. In vitro cellular uptake, cytotoxicity, cell migration, in vivo biodistribution, antitumor activity, and histopathological studies were performed.

Results

Compared with unmodified LPs (Cur-CA4P LPs), Cur-CA4P/GA LPs were taken up effectively by human hepatocellular carcinoma cells (BEL-7402) and showed higher cytotoxicity than free drugs. In vivo real-time near-infrared fluorescence–imaging results indicated that GA-targeted LPs increased accumulation in the tumor region. Moreover, Cur-CA4P/GA LPs showed stronger inhibition of tumor proliferation than Cur, Cur + CA4P, and Cur-CA4P LPs in vivo antitumor studies, which was also verified by H&E staining.

Conclusion

GA-modified LPs can serve as a promising nanocarrier for liver-targeted co-delivery of antitumor drugs against hepatocellular carcinoma.

Potential of Nanomaterial Applications in Dietary Supplements and Foods for Special Medical Purposes

Dietary supplements and foods for special medical purposes are special medical products classified according to the legal basis. They are regulated, for example, by the European Food Safety Authority and the U.S. Food and Drug Administration, as well as by various national regulations issued most frequently by the Ministry of Health and/or the Ministry of Agriculture of particular countries around the world. They constitute a concentrated source of vitamins, minerals, polyunsaturated fatty acids and antioxidants or other compounds with a nutritional or physiological effect contained in the food/feed, alone or in combination, intended for direct consumption in small measured amounts. As nanotechnology provides "a new dimension" accompanied with new or modified properties conferred to many current materials, it is widely used for the production of a new generation of drug formulations, and it is also used in the food industry and even in various types of nutritional supplements. These nanoformulations of supplements are being prepared especially with the purpose to improve bioavailability, protect active ingredients against degradation, or reduce side effects. This contribution comprehensively summarizes the current state of the research focused on nanoformulated human and veterinary dietary supplements, nutraceuticals, and functional foods for special medical purposes, their particular applications in various food products and drinks as well as the most important related guidelines, regulations and directives.

Advances and challenges in liposome digestion: Surface interaction, biological fate, and GIT modeling

During the past 50 years, there has been increased interest in liposomes as carriers of pharmaceutical, cosmetic, and agricultural products. More recently, much progress has been made in the use of surface-modified formulas in experimental food matrices. However, before the viability and the applications of nutrients in liposomal form in the edible field can be determined, the digestion behavior along the human gastrointestinal tract (GIT) must be clarified. In vitro digestion models, from static models to dynamic mono-/bi-/multi-compartmental models, are increasingly being developed and applied as alternatives to in vivo assays. This review describes the surface interactions of liposomes with their encapsulated ingredients and with external food components and updates the biological fate of liposomes after ingestion. It summarizes current models for the human stomach and intestine that are available and their relevance in nutritional studies. It highlights limitations and challenges in the use of these models for liposomal colloid system digestion and discusses crucial factors, such as enzymes and bile salts, that affect liposomal bilayer degradation.

Glutathione-sensitive PEGylated curcumin prodrug nanomicelles: Preparation, characterization, cellular uptake and bioavailability evaluation

The anti-tumor efficacy of curcumin can be markedly improved by nano-drug self-delivery systems with high drug loading capacity and smart stimulus-triggered drug release in tumor cells. Herein, a type of novel, glutathione (GSH)-responsive, PEGylated prodrug nano-micelles (PPNMs) was prepared by self-assembly of curcumin-s-s-vitamin E/mPEG2k-DSPE mixture. The PPNMs (entrapment efficiency: 96.7%) was acceptably stable in water with a mean particle size of 29.84 nm. Compared with curcumin-loaded mPEG2k-DSPE nano-micelles (CUR-NMs), PPNMs showed a higher drug loading (1.68% vs 27.3%) and remarkably improved the chemical stability of curcumin in phosphate buffer saline (PBS) (pH = 7.4), 10% FBS culture medium, and rat plasma. In vitro release study showed that PPNMs could redox responsively control the release of curcumin from the prodrug. Moreover, PPNMs showed a cytotoxicity in HepG2 cells similar to that of the free curcumin; however, when the HepG2 cells were pretreated with 1 mM GSH, PPNMs displayed a markedly enhanced cytotoxicity and cellular uptake than the free curcumin. After intravenous injection, PPNMs showed an increased half-life in blood circulation (10.6-fold) and bioavailability (107-fold) compared with the free curcumin injection. Altogether, the prodrug nano-micelles represent a promising preparation for sustained and controlled delivery of curcumin with enhanced antitumor activity.

Fabrication and Characterization of Curcumin-Loaded Liposomes Formed from Sunflower Lecithin: Impact of Composition and Environmental Stress

There is significant interest in the formulation of liposome-based delivery systems using cheap plant-based commercial sources of lecithin. This study evaluated the impact of phospholipid type on the formation, stability, and curcumin-loading of sunflower liposomes. Four kinds of sunflower lecithin (Sunlipon 50, 65, 75, and 90) with different phosphatidylcholine (PC) levels were used to prepare the liposomes using microfluidization. The particle size, surface charge, microstructure, and stability of the liposomes were determined. All four kinds of lecithin were suitable for fabricating stable liposomes regardless of the PC content. Curcumin was loaded into the liposomes using a newly developed pH-driven method. The loading capacity and heat stability of curcumin increased as the PC content of the lecithin increased. These results showed that commercial plant-based lecithins may be suitable for overcoming some of the hurdles normally associated with using liposomes in the food industry, such as high cost and poor stability.

Strategies for brain-targeting liposomal delivery of small hydrophobic molecules in the treatment of neurodegenerative diseases

Neurodegenerative diseases (NDs), including Alzheimer's disease (AD) and Parkinson's disease (PD), threaten the health of an ever-growing number of older people worldwide; so far, there are no effective cures. Significant efforts have been devoted to developing new drugs for NDs in recent years, and some small molecules have been shown to be promising in preclinical studies. However, the major challenge for brain-targeting drugs is how to efficiently deliver the drugs across the blood-brain barrier (BBB) to desired targets. To address this issue, liposomal delivery systems have proved to be ideal carriers for neuroprotective small molecules. Here, we summarize recent advances in the brain-targeting liposomal delivery of small hydrophobic molecules (SHMs) and propose strategies for developing liposomal SHMs as disease-modifying neurotherapeutics for NDs.