Table 3.
Nanoparticles and nanostructured materials for probiotic encapsulation.
| Material Type | Description | Applications | Advantages | Disadvantages |
|---|---|---|---|---|
| Nanocellulose [16,18] | Available in CNC and CNF forms. Known for its low toxicity, biocompatibility, and adjustable surface properties. It has been shown to improve the properties of probiotic delivery systems when used as an encapsulating material. | Probiotic Encapsulation |
Biocompatible and eco-friendly; provides mechanical strength and adjustable surface properties for better encapsulation. | Limited protection against extreme pH and enzymes. |
| Magnesium Oxide Nanoparticles (MgO NPs) [16,18] |
Attracted attention due to its high surface area, non-toxicity, mechanical resistance, thermal stability, and low cost. Used for microencapsulation of probiotics, showing an improvement in probiotic viability in acidic environments. | Microencapsulation of Probiotics | Enhances probiotic viability in acidic environments; offers mechanical resistance and thermal stability. | Potential aggregation in biological media; requires careful surface modification. |
| Chitosan Nanoparticles (CSNPs) [16,18,114] |
Derived from the alkaline deacetylation of chitin; chitosan is a natural polysaccharide with cationic properties, biocompatibility, non-toxicity, and low cost. Chitosan nanoparticles have shown promise for the encapsulation of probiotic cells, protecting them in the GI tract and improving their mucoadhesive properties. | Encapsulation and Protection in GI Tract | Biocompatible; non-toxic; enhances mucoadhesive properties, protecting probiotics in the GI tract. | Limited solubility in water and some solvents; potential deacetylation challenges. |
| Eudragit S100 Nanoparticles [16,18,114] |
A synthetic anionic polymer derived from methacrylic acid and methyl methacrylate ester. Its solubility depends on pH, being insoluble in strongly acidic solutions and slightly soluble in regions of the digestive tract with neutral to weakly alkaline pH. Used to improve viability of probiotic bacteria. | Enhancing Probiotic Viability | Effective at protecting probiotics in acidic GI environments; pH-responsive solubility for targeted release. | Requires careful formulation to achieve desired solubility and release profiles. |
| Starch Nanoparticles [18,80] |
One of the most abundant biopolymers in nature; produced by many plants and crops. Starch nanoparticles and nanocrystals have been used for biomedical applications, especially in drug delivery. Although, not the best candidate for probiotic microencapsulation due to potential immediate release in hostile environments. | Potential for Probiotic Encapsulation | Natural and biodegradable; potentially low cost. | Possible immediate release in hostile environments, modifications necessary for stability. |
| Liposomes [124] | Spherical vesicles composed of one or more lipid layers surrounding an aqueous core. Morphologically similar to cell membranes, they can encapsulate hydrophilic drugs in their aqueous core and lipophilic drugs in the lipid bilayer, making them versatile for the delivery of a wide range of therapies. | Wide Range of Therapy Delivery | Can encapsulate both hydrophilic and lipophilic compounds; biocompatible and versatile for various therapies. | Stability issues in the GI tract; potential for leakage or fusion with other lipids. |
| Polymeric Nanoparticles (PNPs) [124] |
Colloidal mixtures of biocompatible and biodegradable polymers forming a dense matrix; capable of encapsulating lipophilic drugs within its structure. These nanoparticles offer steric stabilization, protection from enzymatic degradation, and controlled drug release. | Drug Delivery and Stabilization | Protection from enzymatic degradation; controlled release; steric stabilization. |
Potential for immune response; complexity in manufacturing. |
| Solid Lipid Nanoparticles (SLNs) [124] |
Colloidal dispersions of lipids that solidify at room or body temperature. They offer physical stability, drug protection, and low toxicity. Capable of encapsulating both hydrophilic and lipophilic drugs. | Drug Encapsulation | Physical stability; drug protection; low toxicity. | Limited drug loading capacity; potential for drug expulsion during storage. |
| Micelles [125] |
Composed of amphiphilic molecules (having a hydrophilic and a hydrophobic part), micelles form core–shell structures where the hydrophobic core can encapsulate lipophilic drugs, improving their solubility and bioavailability. | Enhancing Solubility and Bioavailability | Improves solubility and bioavailability of lipophilic drugs; simple to prepare. | Critical micelle concentration dependent stability; potential dilution issues in vivo. |
| Nanoemulsions (NE) [124] | Colloidal systems containing oil, water, and surfactants; capable of improving the solubility of water-insoluble drugs and offering controlled drug release. | Solubility Improvement and Controlled Release | Enhances solubility of water-insoluble drugs; controlled release capabilities. | Physical stability over time can be challenging, requiring surfactants for stabilization. |
| Dendrimers [124] | Highly branched polymeric structures providing a platform for drug conjugation, aimed at improving solubility, stability, and efficacy of drug delivery across the blood–brain barrier. | Drug Delivery Efficiency | High drug loading capacity; targeted delivery potential; modifiable surface for functionalization. | Complexity in synthesis; potential toxicity depending on composition and dose. |
| DNA-based Nanodevices [120,122,123] |
Utilizing the precision of DNA to form nanoscale structures, these devices are tailored for specific interactions within biological systems. They are especially promising for the accurate placement of probiotics or psychobiotics within the gastrointestinal tract. | Targeted Delivery of Probiotics and Psychobiotics | Precise control over delivery location; capable of protecting cargo through harsh conditions; programmable release triggered by environmental factors. | Complexity in design and synthesis; potential for unanticipated interactions with the body’s biochemistry. |
| Quantum Dots (QDs) [124,126] | Nanocrystalline semiconductors offering unique electronic and optical properties, such as high emission and photostability; useful for imaging and diagnosis of CNS disorders, as well as drug delivery. | Imaging, Diagnosis, and Drug Delivery | High photostability and emission for imaging; potential for targeted drug delivery. | Toxicity concerns, especially with heavy-metal-containing QDs; stability in biological environments |