Synthetic surfactant- and cross-linker-free preparation of highly stable lipid-polymer hybrid nanoparticles as potential oral delivery vehicles

Rational design of solid lipid-polymer hybrid nanoparticles: An innovative glycoalkaloids-carrier with potential for topical melanoma treatment

Despite the promising potential of Solanum plant glycoalkaloids in combating skin cancer, their clinical trials have been halted due to dose-dependent toxicity and poor water solubility. In this study, we present a rational approach to address these limitations and ensure colloidal stability of the nanoformulation over time by designing solid lipid-polymer hybrid nanoparticles (SLPH). Leveraging the biocompatible and cationic properties of polyaspartamides, we employed a new polyaspartamide derivative (P1) as a raw material for this class of nanostructures. Subsequently, we prepared SLPH through a one-step process involving hot-melt emulsification followed by ultrasonication. The physicochemical properties of the SLPH were thoroughly characterized using dynamic light scattering (DLS), ζ-potential analysis, nanoparticle tracking analysis (NTA), differential scanning calorimetry (DSC), Fourier-transform infrared spectroscopy (FT-IR), and transmission electron microscopy (TEM). The optimized formulation exhibited long-term stability over six months under low temperatures, maintaining a particle size around 200 nm, a polydispersity index (PdI) lower than 0.2, and a ζ-potential between +35-40 mV. Furthermore, we evaluated the cytotoxic effect of the SLPH against human cutaneous melanoma cells (SK-MEL-28) compared to human foreskin fibroblast cells (HFF-1). Encapsulation of glycoalkaloids into the nanoparticles (SLPH-GE) resulted in a two-fold greater selective cytotoxic profile for melanoma cells than glycoalkaloids-free (GE). The nanoparticles disrupted the stratum corneum barrier with a penetration depth of approximately 77 μm. These findings underscore the potential of the developed nanosystem as an effective glycoalkaloid carrier with suitable colloidal and biological properties for further studies in topical treatment strategies for cutaneous melanoma.

Polymer-lipid hybrid nanoparticles as potential lipophilic anticancer drug carriers

Nanocarrier systems are widely used for drug delivery applications, but limitations such as the use of synthetic surfactants, leakage of toxic drugs, and a poor encapsulation capacity remain as challenges. We present a new hybrid nanocarrier system that utilizes natural materials to overcome these limitations and improve the safety and efficacy of drug delivery. The system comprises a biopolymeric shell and a lipid core, encapsulating the lipophilic anticancer drug paclitaxel. Bovine serum albumin and dextran, in various molecular weights, are covalently conjugated via Maillard reaction to form the shell which serves as a stabilizer to maintain nanoparticle integrity. The properties of the system, such as Maillard conjugate concentration, protein/polysaccharide molar ratio, and polysaccharide molecular weight, are optimized to enhance nanoparticle size and stability. The system shows high stability at different pH conditions, high drug loading capacity, and effective in vitro drug release through the trigger of enzymes and passive diffusion. Serine proteases are used to digest the protein portion of the nanoparticle shell to enhance the drug release. This nanocarrier system represents a significant advancement in the field of nanomedicine, offering a safe and effective alternative for the delivery of lipophilic drugs.

Proteolytic Resistance Determines Albumin Nanoparticle Drug Delivery Properties and Increases Cathepsin B, D, and G Expression

Proteolytic activity is pivotal in maintaining cell homeostasis and function. In pathological conditions such as cancer, it covers a key role in tumor cell viability, spreading to distant organs, and response to the treatment. Endosomes represent one of the major sites of cellular proteolytic activity and very often represent the final destination of internalized nanoformulations. However, little information about nanoparticle impact on the biology of these organelles is available even though they represent the major location of drug release. In this work, we generated albumin nanoparticles with a different resistance to proteolysis by finely tuning the amount of cross-linker used to stabilize the carriers. After careful characterization of the particles and measurement of their degradation in proteolytic conditions, we determined a relationship between their sensitivity to proteases and their drug delivery properties. These phenomena were characterized by an overall increase in the expression of cathepsin proteases regardless of the different sensitivity of the particles to proteolytic degradation.

Multifunctional carbonized nanogels to treat lethal acute hepatopancreatic necrosis disease

Background

Shrimp aquaculture has suffered huge economic losses over the past decade due to the outbreak of acute hepatopancreatic necrosis disease (AHPND), which is mainly caused by the bacteria Vibrio parahaemolyticus (V. parahaemolyticus) with the virulence pVA1 plasmid, which encodes a secretory photorhabdus insect-related (Pir) toxin composed of PirA and PirB proteins. The Pir toxin mainly attacks the hepatopancreas, a major metabolic organ in shrimp, thereby causing necrosis and loss of function. The pandemic of antibiotic-resistant strains makes the impact worse.

Methods

Mild pyrolysis of a mixture of polysaccharide dextran 70 and the crosslinker 1,8-diaminooctane at 180 ℃ for 3 h to form carbonized nanogels (DAO/DEX-CNGs) through controlled cross-linking and carbonization. The multifunctional therapeutic CNGs inherit nanogel-like structures and functional groups from their precursor molecules.

Results

DAO/DEX-CNGs manifest broad-spectrum antibacterial activity against Vibrio parahaemolyticus responsible for AHPND and even multiple drug-resistant strains. The polymer-like structures and functional groups on graphitic-carbon within the CNGs exhibit multiple treatment effects, including disruption of bacterial membranes, elevating bacterial oxidative stress, and neutralization of PirAB toxins. The inhibition of Vibrio in the midgut of infected shrimp, protection of hepatopancreas tissue from Pir toxin, and suppressing overstimulation of the immune system in severe V. parahaemolyticus infection, revealing that CNGs can effectively guard shrimp from Vibrio invasion. Moreover, shrimps fed with DAO/DEX-CNGs were carefully examined, such as the expression of the immune-related genes, hepatopancreas biopsy, and intestinal microbiota. Few adverse effects on shrimps were observed.

Conclusion

Our work proposes brand-new applications of multifunctional carbon-based nanomaterials as efficient anti-Vibrio agents in the aquatic industry that hold great potential as feed additives to reduce antibiotic overuse in aquaculture.

Graphical Abstract

Supplementary Information

The online version contains supplementary material available at 10.1186/s12951-021-01194-8.

Natural polysaccharides based self-assembled nanoparticles for biomedical applications - A review

In recent years, nanoparticles (NPs) derived from the self-assembly of natural polysaccharides have shown great potential in the biomedical field. Here, we described several self-assembly modes of natural polysaccharides in detail, summarized the natural polysaccharides mostly used for self-assembly, and provided insights into the current applications and achievements of these self-assembled NPs. As one of the most widespread substances in nature, most natural polysaccharides exhibit advantages of biodegradability, low immunogenicity, low toxicity, and degradable properties. Therefore, they have been fully explored, and the application of chitosan, hyaluronic acid, alginate, starch, and their derivatives has been extensively studied, especially in the fields of biomedical. Polysaccharides based NPs were proved to improve the solubility of insoluble drugs, enhance tissue target ability and realize the controlled and sustained release of drugs. When modified by hydrophobic groups, the amphiphilic polysaccharides can self-assemble into NPs. Other driven forces of self-assembly include electrostatic interaction and hydrogen bonds. Up to the present, polysaccharides-based nanoparticles have been widely applied for tumor treatment, antibacterial application, gene therapy, photodynamic therapy and transporting insulin.

Enhanced Bioavailability of Dihydrotanshinone I-Bovine Serum Albumin Nanoparticles for Stroke Therapy

Dihydrotanshinone I (DHT) is a natural component in Salvia miltiorrhiza and has been widely researched for its multiple bioactivities. However, poor solubility and biocompatibility of DHT limit its desirable application for clinical purposes. Herein, DHT was encapsulated with bovine serum albumin (BSA) to enhance bioavailability. Compared to free DHT, DHT-BSA NPs (nanoparticles) showed an improved solubility in normal saline and increased protection against hydrogen peroxide-induced oxidative damage in PC12 cells. In addition, DHT-BSA NPs administered by intravenous injection displayed a significant efficacy in the middle cerebral artery occlusion/reperfusion models, without any impact on the cerebral blood flow. In summary, DHT-BSA NPs show an enhanced bioavailability compared with free DHT and a successful penetration into the central nervous system for stroke therapy, demonstrating their application potential in cardio-cerebrovascular diseases.

Hydrogel-based therapeutic angiogenesis: An alternative treatment strategy for critical limb ischemia

Critical limb ischemia (CLI) is the most severe clinical manifestation of peripheral arterial disease (PAD), resulting in the total or partial loss of limb function. Although the conventional treatment strategy of CLI (e.g., medical treatment and surgery) can improve blood perfusion and restore limb function, many patients are unsuitable for these strategies and they still face the threats of amputation or death. Therapeutic angiogenesis, as a potential solution for these problems, attempts to manipulate blood vessel growth in vivo for augment perfusion without the help of extra pharmaceutics and surgery. With the rise of interdisciplinary research, regenerative medicine strategies provide new possibilities for treating many clinical diseases. Hydrogel, as an excellent biocompatibility material, is an ideal candidate for delivering bioactive molecules and cells for therapeutic angiogenesis. Besides, hydrogel could precisely deliver, control release, and keep the bioactivity of cargos, making hydrogel-based therapeutic angiogenesis a new strategy for CLI therapy. In this review, we comprehensively discuss the approaches of hydrogel-based strategy for CLI treatment as well as their challenges, and future directions.

Application of Advanced Emulsion Technology in the Food Industry: A Review and Critical Evaluation

The food industry is one of the major users of emulsion technology, as many food products exist in an emulsified form, including many dressings, sauces, spreads, dips, creams, and beverages. Recently, there has been an interest in improving the healthiness, sustainability, and safety of foods in an attempt to address some of the negative effects associated with the modern food supply, such as rising chronic diseases, environmental damage, and food safety concerns. Advanced emulsion technologies can be used to address many of these concerns. In this review article, recent studies on the development and utilization of these advanced technologies are critically assessed, including nanoemulsions, high internal phase emulsions (HIPEs), Pickering emulsions, multilayer emulsions, solid lipid nanoparticles (SLNs), multiple emulsions, and emulgels. A brief description of each type of emulsion is given, then their formation and properties are described, and finally their potential applications in the food industry are presented. Special emphasis is given to the utilization of these advanced technologies for the delivery of bioactive compounds.

Polymer-Lipid Pharmaceutical Nanocarriers: Innovations by New Formulations and Production Technologies

Some issues in pharmaceutical therapies such as instability, poor membrane permeability, and bioavailability of drugs can be solved by the design of suitable delivery systems based on the combination of two pillar classes of ingredients: polymers and lipids. At the same time, modern technologies are required to overcome production limitations (low productivity, high energy consumption, expensive setup, long process times) to pass at the industrial level. In this paper, a summary of applications of polymeric and lipid materials combined as nanostructures (hybrid nanocarriers) is reported. Then, recent techniques adopted in the production of hybrid nanoparticles are discussed, highlighting limitations still present that hold back the industrial implementation.

Preparation of Curdlan sulphate - Chitosan nanoparticles as a drug carrier to target Mycobacterium smegmatis infected macrophages

In this study, curdlan sulphate - chitosan nanoparticles were prepared through polyelectrolyte complexing at a mass ratio of 2:1 respectively. The curdlan was produced by fermentation with Agrobacterium sp. ATCC 31750, which was then sulphated to form the polyanionic polymer. A first-line tuberculosis drug, Rifampicin and a phytochemical, DdPinitol, were encapsulated into Curdlan Sulphate (CS) - Chitosan Nanoparticles (C) (CSC NPs) of size 205.41 ± 7.24 nm. The drug release kinetics followed a Weibull model with initial burst release (48 % Rifampicin and 27 % d-Pinitol within 6 h), followed by a sustained release. The prepared CSC: d-PIN + RIF NPs was cytocompatible and entered the M.smegmatis infected macrophages through multiple endocytic pathways including clathrin, caveolae and macropinocytosis. They showed superior bactericidal activity (2.4-2.7 fold) within 4 h when compared to free drug Rifampicin (1.6 fold). The drug encapsulated CSC: RIF suppressed the pro-inflammatory gene (TNF-α by 3.66 ± 0.19 fold) and CSC: d-PIN + RIF increased expression of the anti-inflammatory gene (IL-10 by 13.09 ± 0.47 fold). Expression of TGF- β1 gene also increased when treated with CSC: d-PIN + RIF (13.00 ± 0.19 fold) which provided the immunomodulatory activity of the encapsulated CSC NPs. Thus, curdlan sulphate - chitosan polyelectrolyte complex can be a potential nanocarrier matrix for intracellular delivery of multiple drugs.

Biopolymer-Based Nanotechnology Approaches To Deliver Bioactive Compounds for Food Applications: A Perspective on the Past, Present, and Future

Food nanotechnology is an emerging and rapidly evolving field that encompasses an extremely broad range of disciplines and has found various applications in different food sectors. The objective of this perspective is to update the current knowledge on the nanotechnology-based approaches to prepare delivery vehicles for bioactive compounds. Research progress on the development of nanoparticles made from food biopolymers (i.e., protein and polysaccharide) is particularly highlighted. In addition, two types of most recently developed nanoscale delivery systems, i.e., protein-polysaccharide complex and lipid-biopolymer hybrid nanoparticles, are introduced, and their relevant applications are discussed. Finally, suggestions for future research directions on developing safe, effective, and edible nanoscale delivery vehicles for food applications are provided.

Improved Physicochemical Properties of Curcumin-Loaded Solid Lipid Nanoparticles Stabilized by Sodium Caseinate-Lactose Maillard Conjugate

To improve the water solubility, antioxidant activity, and chemical stability of curcumin, solid lipid nanoparticles (SLNs) were fabricated using equal masses of propylene glycol monopalmitate and glyceryl monostearate as the lipid matrix and sodium caseinate-lactose (NaCas-Lac) Maillard conjugate as the emulsifier. The entrapment efficiency was more than 90% when curcumin was 2.5% and 5.0% of lipid mass, and the SLNs were stable during 30-day storage. SLNs stabilized by NaCas-Lac showed better physicochemical properties than those prepared with NaCas, including higher sphericity and homogeneity; higher entrapment efficiency; better stability against pH, ionic strength, and simulated gastrointestinal digestions; and more controlled release. SLNs also greatly enhanced the antioxidant activity of encapsulated curcumin and the retention of curcumin during storage. Therefore, the present SLNs may find applications to deliver lipophilic compounds in functional foods and beverages.

Improved oral delivery of tilianin through lipid-polymer hybrid nanoparticles to enhance bioavailability

Tilianin (TIL) may prevent and treat myocardial ischemia reperfusion injuries. However, its oral administration is hampered by its low bioavailability. The present study aimed to formulate lipid-polymer hybrid nanoparticles (LPHNs) as carriers for the sustained release and oral bioavailability enhancement of TIL in vitro and in vivo. A nanodrug delivery system of TIL-loaded LPHNs (TIL-LPHNs) was constructed. TIL-LPHNs were prepared via a self-assembly method, and their particle size, polymer dispersity index (PDI), zeta potential, encapsulation efficiency (EE) and morphology were investigated. In addition, pharmacokinetic studies were performed in vivo. The TIL-LPHN formulation produced a spherical, homogeneous, smooth surface and multi-lamellar structured nanoparticles. The particle size and distribution profile of TIL-LPHNs had a mean particle diameter of 54.6 ± 5.3 nm and PDI of 0.112 ± 0.017. The zeta potential was -33.4 ± 4.7 mV. The EE of TIL-LPHNs was 86.6 ± 3.6%, which was determined with the dialysis method. The TIL-LPHNs significantly enhanced the oral bioavailability of TIL with a 3.7-fold increase in the area under the concentration-time curve in comparison with the TIL solution. These findings support the potential use of LPHNs in improving the stability and bioavailability of TIL via oral administration.

Biological fate of ingested lipid-based nanoparticles: current understanding and future directions

In recent decades, lipid-based nanoparticles (LN) have received considerable attention as nanoscale delivery systems to improve oral bioavailability of poorly absorbed bioactive compounds for health promotion and disease prevention. However, scientific studies on the biological fate of orally administered LN are very limited and the molecular mechanisms by which they are absorbed through the intestinal lumen into the circulation remain unclear. This paper aims to provide an overview of the biological fate of orally administered LN by reviewing recent studies on both cell and animal models. In general, the biological fate of ingested LN in the gastrointestinal tract is primarily determined by their initial physicochemical characteristics (such as the particle size, surface properties, composition and structure), and their absorption mainly occurs within the small intestine. In particular, depending upon the composition, LN can be either digestible or indigestible, with two distinct biological fates for each type of LN. The detailed absorption mechanisms and uptake pathways at molecular, cellular and whole body levels for each type of LN are discussed in detail. Limitations of current research and our vision for future directions to study the biological fate of ingested LN are also provided in this critical review.

Potential Use of the Maillard Reaction for Pharmaceutical Applications: Gastric and Intestinal Controlled Release Alginate-Albumin Beads

In this study, bovine serum albumin (BSA) and alginate (ALG) conjugates were synthesized by the Maillard reaction in order to evaluate their potential to develop controlled release drug delivery systems. The progress of the Maillard reaction was evidenced using ultraviolet (UV) absorbance, determination of BSA remaining free amino groups, and sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). BSA-ALG conjugates possessed enhanced and tunable viscosity, foamability and foam stability. Foam generated from BSA-ALG conjugate solution was used to prepare floating gastroretentive calcium ALG beads. Unlike traditional ALG beads, BSA-ALG foam beads were able to float and sustain the ciprofloxacin (CIP) release in gastric medium. Interestingly, intestinal beads made of ALG, BSA-ALG physical mixture and BSA-ALG conjugate resulted in different release rates and orders of indomethacin (IND) in simulated intestinal fluids; while beads based on a physical mixture of BSA-ALG resulted in a first order sustained release profile, both systems based on ALG and BSA-ALG conjugate displayed zero order sustained release profiles with IND being released at a slower rate from the conjugate beads.

Solid Lipid-Polymer Hybrid Nanoparticles by In Situ Conjugation for Oral Delivery of Astaxanthin

Solid lipid-polymer hybrid nanoparticles (SLPN) are nanocarriers made from a combination of polymers and lipids, integrating the advantages of biocompatible lipid-based nanoparticles and gastrointestinal (GI)-stable polymeric nanoparticles. In this study, a novel preparation strategy was proposed to fabricate GI-stable SLPN through in situ conjugation between oxidized dextran and bovine serum albumin. Effects of molecular weight of dextran (20, 40, 75, and 150 kDa), conjugation temperature (65 °C, 75 °C, and 85 °C), and time (30, 60, 120 min) on the particulate characteristics and stability were comprehensively investigated and optimized. As heating temperature increased from 65 °C to 75 °C, the particle size of SLPN increased from 139 to 180 nm with narrow size distribution, but when the temperature reached 85 °C severe aggregation was observed after 60 min. SLPN prepared with 40 kDa oxidized dextran under 85 °C/30 min heating condition exhibited excellent GI stability with no significant changes in particle size and PDI after incubation in simulated GI fluids. The prepared SLPN were then used to encapsulate astaxanthin, a lipophilic bioactive compound, studied as a model nutrient. After encapsulation in SLPN, antioxidant activity of astaxanthin was dramatically enhanced in aqueous condition and a sustained release was achieved in simulated GI fluids. Therefore, the SLPN developed in this study are a promising oral delivery system for lipophilic compounds, such as astaxanthin.