PNPs are polymers, a nanomaterial with an average size between 1 and 1000 nanometers made of biocompatible, biodegradable polymers. These particles can be made up of any sized therapy agent (small molecule drug, protein, nucleic acid, or vaccine) and have advantages in terms of controlled release, stability and targeted delivery. Polymeric nanoparticles are especially useful for drug delivery because they can help to make poorly water-soluble drugs solubilized and bioavailable, while preventing unwanted effects through a localization into tissues or cells.
There are many different kinds of polymeric nanoparticles depending on their structure, composition and process of manufacture:
Nanospheres: These are solid particles containing the therapeutic drug evenly distributed in the polymer matrix. This is a good design for long term and controlled drug release, because the drug is slowly released as the polymer breaks down.
Nanocapsules: A nanocapsule is a core-shell capsule wherein the drug inside the capsule is contained in the core and the outer shell of the capsule is made of a polymer. This type of structure gives better stability and control over how the drug gets released from the center.
Polymeric Micelles: They are a nanoparticle that self-assembles amphiphilic block copolymers in water. Its hydrophobic core could hold hydrophobic drugs. Its hydrophilic shell made the micelle more releasable in biological fluids. Polymeric micelles are especially good for transporting drugs that are not highly water-soluble.
Dendrimers: Dendrimers are tree-like structures with very dense branches that can have well-defined surface features, accurate molecular weight, and load large numbers of drug molecules. Specifically targeted drug delivery and gene therapy are applications where dendrimers excel.
Fig.1 Structure diagram of nanocapsules and nanospheres. (Zielińska, Aleksandra, et al., 2020)
There are many different kinds of polymeric nanoparticles that have been engineered for therapeutic purposes. Some well-known examples include:
PLGA Nanoparticles: PLGA, one of the most common biodegradable polymers used for the nanoparticles is poly (lactic-co-glycolic acid). PLGA nanoparticles are deployed for the long-term release of medication and they have been applied to deliver chemotherapy drugs, vaccines and proteins.
PEG Nanoparticles: PEG is also used in many nanoparticles because of the hydrophilic properties of PEG which make drugs solubilized and stable. The benefits of PEGylated nanoparticles are also that they bypass the immune system, and therefore have a long time of circulation in the body.
Chitosan Nanoparticles: Chitosan is a natural polymer from chitin, it's biocompatible, biodegradable and non-toxic. Chitosan nanoparticles can be administered by mouth or topically and have been tested for gene delivery and vaccines.
Polylactic Acid (PLA) Nanoparticles: PLA is a biodegradable polymer made from renewable resources. PLA nanoparticles have a long track record in drug delivery applications requiring a long-term or controlled release, tissue engineering, and regenerative medicine.
Polymeric nanoparticles can be synthesized using a variety of approaches, and they can be made with a range of sizes, surface charges and loading capacity for drugs. The most used synthesis techniques are:
Emulsion Solvent Evaporation: The polymer solution is immersed in an organic solvent and the drug is dissolve or dissolved in the polymer solution. The solution is then mixed with an aqueous phase of surfactants, and the solution forms an emulsion. The solvent evaporates and polymeric nanoparticles are produced. We generally use this method for hydrophobic polymers such as PLGA.
Nanoprecipitation: Nanoprecipitation is the precipitation of a polymer in a bad solvent. The process is usually used for amphiphilic block copolymers (blocks are hydrophobic and the other hydrophilic). When it rains, the hydrophobic block becomes the heart and the hydrophilic block is the shell. it has micellar structure.
Solvent Extraction-Evaporation: Similar to emulsion solvent evaporation, here an emulsion of an organic solvent is made. Drug is dispersed in the organic and when the solvent evaporates, the drug-laden nanoparticles are produced. This is how we manufacture nanoparticles with a stable release profile.
Coacervation: In coacervation, phase separation of the polymer is done by solvent to create nanoparticles. This is usually done for natural polymers like chitosan and is most commonly applied when designing nanoparticles for the administration of drugs through the mouth.
Supercritical Fluid Technology: It's a highly sophisticated technique in which supercritical fluids are used as solvents for the creation of nanoparticles. There are a number of benefits to the method, including no residue solvents which is very important for pharmaceutical use. It can also be used to capsulate drugs or biomolecules.
Several polymeric nanoparticle-based drug delivery systems have received FDA approval for clinical use. These include:
Abraxane: Abraxane is a nanoparticle formulation of paclitaxel, a chemotherapy drug, encapsulated in albumin-coated nanoparticles. The nanoparticles improve the solubility and bioavailability of paclitaxel, and the albumin coating facilitates passive targeting to tumor tissues. Abraxane is used in the treatment of breast cancer, non-small cell lung cancer, and pancreatic cancer.
Doxil: Doxil is a liposomal formulation of doxorubicin, encapsulating the drug in a lipid nanoparticle. While it is not technically a polymeric nanoparticle, it shares similar properties. Doxil improves the pharmacokinetics of doxorubicin and reduces systemic toxicity, particularly cardiotoxicity, making it a safer option for cancer patients.
Onivyde: Onivyde is a liposomal formulation of irinotecan, a chemotherapy drug used in the treatment of metastatic pancreatic cancer. Although this formulation is liposomal in nature, it has paved the way for the use of nanoparticles in cancer therapy due to its enhanced efficacy and reduced side effects.
Polymeric nanoparticles offer numerous advantages in pharmaceutical applications, making them ideal for drug delivery and cancer therapy:
Controlled and Sustained Drug Release: Polymeric nanoparticles can be engineered to provide sustained and controlled drug release over extended periods. This reduces the frequency of drug administration, improves patient compliance, and enhances therapeutic outcomes.
Enhanced Drug Solubility and Bioavailability: Many therapeutic agents, especially hydrophobic drugs, suffer from poor solubility and bioavailability. By encapsulating these drugs in polymeric nanoparticles, their solubility is improved, which can lead to more efficient drug delivery and therapeutic effectiveness.
Targeted Drug Delivery: One of the key advantages of polymeric nanoparticles is the ability to target specific cells or tissues. By modifying the surface of nanoparticles with ligands such as antibodies, peptides, or small molecules, they can selectively bind to receptors on target cells, such as tumor cells, thus enhancing the effectiveness of the treatment while minimizing side effects.
Reduced Toxicity: Polymeric nanoparticles can reduce the systemic toxicity of drugs by ensuring that the drug is delivered directly to the target site, thus minimizing exposure to healthy tissues.
Versatility in Drug Loading: Polymeric nanoparticles can accommodate a broad range of therapeutic agents, including small molecule drugs, proteins, nucleic acids, and even vaccines. This versatility makes them a powerful tool in the development of combination therapies and personalized medicine.
Polymeric nanoparticles' primary applications are in cancer therapy and drug delivery, offering controlled release, enhanced targeting, improved solubility, and reduced toxicity. They are also explored in gene therapy and vaccine delivery.
Polymeric nanoparticles have revolutionized cancer treatment by enhancing the delivery of chemotherapy drugs directly to tumor sites. Key advantages include:
Targeting Tumor Cells: Surface modifications with tumor-targeting ligands can improve the specificity of polymeric nanoparticles for cancer cells, reducing the off-target effects and improving the efficacy of the drug.
Improving Solubility and Stability: Many chemotherapeutic drugs are poorly soluble in water, limiting their bioavailability and therapeutic effectiveness. By encapsulating these drugs in polymeric nanoparticles, their solubility is enhanced, leading to more efficient treatment.
Overcoming Drug Resistance: Cancer cells often develop resistance to chemotherapy drugs by expelling them from the cell. Polymeric nanoparticles can circumvent this problem by providing sustained release and bypassing some of the resistance mechanisms.
Polymeric nanoparticles have become the gold standard in drug delivery due to their ability to improve the pharmacokinetics and therapeutic outcomes of various drugs. They are used for:
Small Molecule Drugs: Polymeric nanoparticles are particularly useful for delivering hydrophobic drugs, such as paclitaxel, that have poor solubility in water.
Protein and Peptide Delivery: Proteins and peptides often have poor bioavailability due to instability in the bloodstream. Polymeric nanoparticles can encapsulate these biomolecules, protecting them from degradation and improving their delivery to the target site.
Controlled Release: Polymeric nanoparticles can be designed to release drugs over an extended period, ensuring a constant therapeutic effect and reducing the need for frequent drug administration.
BOC Sciences offers a wide range of polymer nanoparticle products as well as customized products in different types to meet a variety of research and application needs. Below is the list of products we can provide, if you have more needs, please contact us to customize the synthesis of your polymeric nanoparticles.
| Product Type | Price |
| Polystyrene Nanoparticles | Inquiry |
| Polyethylene Nanoparticles | Inquiry |
| Polylactide Nanoparticles | Inquiry |
| Polyvinyl Chloride Nanoparticles | Inquiry |
| PLGA Nanoparticles | Inquiry |
| PET Nanoparticles | Inquiry |
| Polyamide Nanoparticles | Inquiry |
| Polypropylene Nanoparticles | Inquiry |
| PCL Nanoparticles | Inquiry |
| PGMA Nanoparticles | Inquiry |
Polymeric nanoparticles are modified with polyethylene glycol (PEG) by grafting or surface coating to improve biocompatibility, circulation time, and reduce immune recognition.
Polymeric nanoparticles are synthesized by emulsion polymerization, nanoprecipitation, or solvent evaporation, using biodegradable polymers like PLGA for controlled drug delivery.
Ultrasound enhances polymeric nanoparticles' drug release by creating mechanical stress, heat, or cavitation effects, improving therapeutic efficacy.
Drugs release from polymeric nanoparticles through diffusion, polymer degradation, or environmental triggers like pH, temperature, or enzymatic action.
Polymeric micelle nanoparticles are self-assembled structures of amphiphilic block copolymers, used for delivering hydrophobic drugs due to their core-shell architecture.
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