CD Bioparticles is a leading manufacturer and supplier of various drug delivery products, including metallic nanoparticles for R&D and commercialization in a variety of application areas. Metal nanoparticles are emerging as a new class of functional nanomaterials in the area of biological sensing, labelling, imaging and therapy due to their unique physical and chemical properties.

Introduction to Metallic Nanoparticles

In general, metal nanoparticles used in the field of biotechnology range in particle size between 10 and 500 nm, seldom exceeding 700 nm, because the nanosize will allow various communications with biomolecules on the cell surfaces and within the cells in way that can be decoded and designated to various biochemical and physiochemical properties of these cells. Recently, various kinds of metal nanocages (NCs) including gold (Au), silver (Ag) and copper (Cu) NCs have been widely exploited for applications in the area of biological sensing, labelling, imaging and therapy. In order to utilize nanoparticles for their application, we need to select and design nanoparticulate systems that are stable, biocompatible, and selectively directed to specific sites in the body after systemic administration. That is why more specific targeting systems are designed to recognize the targeted cells such as cancer cell by modifying with various chemical functional groups which allow them to be conjugated with antibodies, ligands, and drugs of interest. In general, the surface functionalization of these metal NCs can be accomplished through two different ways: functionalization during the synthesis and post-synthesis functionalization.

Functionalization During the Synthesis

Some of the functional groups could be conjugated to the surface of nanoparticles during the synthesis. The robust covalent bond between gold and thiols forms gold–sulfur interface which allows the exploitation of thiols as protecting ligands for the synthesis and functionalization of metal NPs. The functionalization of biomolecules on metal NCs is also very important to provide biocompatible platforms for biomedical applications with minimal toxicity. Various biomolecules such as nucleic acids, proteins, peptides, dendrimers and polymers that have been used to conjugate with various metal nanoparticles based on different biomedical need.

Figure 1. (a) Schematic illustration of the NaOH-mediated NaBH4-reduction method for the synthesis of thiolated Au NCs. (Copyright (2014) Wiley-VCH.) (b) Schematic illustration and the intriguing optical absorption spectra of Au25 NCs protected by negatively charged thiolate ligands collocating with positively charged thiolate ligands. (Copyright (2016) Royal Society of Chemistry)

Post-synthesis Functionalization

Post-synthesis functionalization means that conjugation will be conducted to the already formed mental nanoparticles agents to broaden their applications in biomedical science. During the process, a delicate selection of good stabilizers with desirable terminal functionalities, such as primary amine, carboxylic acid, and alcohol, will be used to prevent the metal NCs from aggregation. There is a wide spectrum of conjugation reagents including small molecules (e.g., folic acid) to macromolecules (e.g., proteins and DNA) and genes. The chemistry for conjugation process is based on the terminal functional groups of the metal NCs and the functional groups of the desired biomolecules. Post-synthesis ligand exchange is another efficient route for surface functionalization of metal NCs in solution by partially or completely exchanged the original ligand with the new ones. Ligand exchange reactions are known to be vital for the surface modification of quantum dots (QDs) and metal nanocrystals.

Our Metallic Nanoparticles Featured Services

CD Bioparticles is specialized in the development of drug delivery systems and customizing nanoparticles for drug delivery utilizing our core technologies. With our high-quality products and services, the efficacy of your drug delivery can be tremendously improved.

We offer custom production of the following types of metal nanoparticles, including:

Gold Nanoparticles (AuNPs):

Gold nanoparticles are tiny particles made of gold atoms. They exhibit unique optical, electronic, and catalytic properties due to their small size and high surface area. They find applications in various fields such as medicine (drug delivery and imaging), electronics (sensors and conductive materials), and catalysis. Their unique properties include:

• Biocompatibility: AuNPs are generally biocompatible and well-tolerated by the body, making them suitable for drug delivery applications.
• Surface Functionalization: Their surface can be easily modified with various molecules, allowing for targeted drug delivery.
• Enhanced Permeability and Retention (EPR) Effect: AuNPs can accumulate in tumor tissues due to leaky vasculature, improving drug delivery to cancer cells.
• Photothermal Therapy: AuNPs can convert absorbed light into heat, enabling localized hyperthermia therapy for cancer treatment.
• Imaging: AuNPs can be used for imaging due to their strong light scattering properties and compatibility with various imaging techniques.

Silver Nanoparticles (AgNPs):

Similar to gold nanoparticles, silver nanoparticles are made of silver atoms. They are known for their antimicrobial properties and are used in various medical and consumer products, such as wound dressings, antibacterial coatings, and water purification systems. Their unique properties include:

• Antimicrobial Properties: AgNPs possess potent antimicrobial effects, which can help prevent infections and promote wound healing.
• Wound Healing: AgNPs can be used in wound dressings to accelerate healing and prevent bacterial growth.
• Toxicity Considerations: Careful consideration is required to balance the beneficial antimicrobial effects with potential cytotoxicity.

Copper Nanoparticles (CuNPs):

Copper nanoparticles possess interesting electrical, thermal, and catalytic properties. They have applications in electronics, catalysis, and as antimicrobial agents. Their unique properties include:

• Antibacterial Properties: CuNPs exhibit strong antibacterial properties, making them suitable for infection control.
• Catalytic Activity: CuNPs can be used for catalytic degradation of toxins and pollutants.
• Angiogenesis Inhibition: Copper-based nanoparticles may inhibit blood vessel growth, potentially useful in anti-cancer therapy.

Metallic Quantum Dots:

Metallic quantum dots are nanoscale semiconductors with unique electronic properties due to quantum confinement effects. They can exhibit size-dependent optical and electronic properties. Their unique properties include:

• Size-Tunable Properties: Quantum dots' emission properties can be tuned by adjusting their size, enabling versatile imaging and drug delivery applications.
• Photostability: Metallic quantum dots exhibit high photostability, enabling longer imaging durations in living systems.
• Multi-Modal Imaging: They can be used for both optical and photoacoustic imaging, providing complementary imaging information.

Metal-Organic Frameworks (MOFs):

MOFs are three-dimensional structures made of metal ions or clusters connected by organic ligands. They have high porosity and surface area, making them suitable for applications such as gas storage, separation, drug delivery, and catalysis. Their unique properties include:

• High Surface Area: MOFs possess large surface areas, allowing for high drug loading capacity.
• Tunable Pore Sizes: Pore structures can be tailored to accommodate different drug molecules and control their release rates.
• Guest-Host Interactions: MOFs can protect drug molecules from degradation and release them in a controlled manner.

Calcium Nanoparticles:

Calcium-based nanomaterials can refer to nanoparticles or materials containing calcium. These materials might have applications in bone regeneration, drug delivery, and imaging due to the importance of calcium in biological systems. Their unique properties include:

• Biocompatibility: Calcium is a naturally occurring element in the body, enhancing the compatibility of these nanoparticles.
• Bone-Targeted Delivery: Calcium nanoparticles can be engineered to target bone tissue, ideal for conditions like osteoporosis or bone cancers.

Magnetic Nanoparticles (MNPs):

Magnetic nanoparticles possess magnetic properties and find applications in various fields, including medicine (magnetic resonance imaging, drug delivery), environmental remediation (water treatment), and electronics (data storage). Their unique properties include:

• Magnetic Targeting: MNPs can be guided to specific sites using external magnetic fields, improving drug delivery accuracy.
• Hyperthermia Therapy: MNPs can generate heat when subjected to alternating magnetic fields, aiding in localized hyperthermia treatment.
• MRI Contrast Agents: MNPs can be used as contrast agents in magnetic resonance imaging to visualize tissue and track drug distribution.

Upconversion Nanoparticles (UCNPs):

Upconversion nanoparticles are capable of converting lower-energy photons into higher-energy photons. They have applications in imaging, solar cells, and biological labeling, as they allow for deeper tissue penetration and reduced autofluorescence. Their unique properties include:

• Deep Tissue Imaging: UCNPs can convert low-energy photons to high-energy photons, enabling deep tissue imaging in vivo.
• Multiplexed Imaging: Different colors of UCNPs can be excited by the same light source, allowing simultaneous multi-color imaging.
• Theranostics: UCNPs can combine imaging and therapy, enabling simultaneous visualization and treatment monitoring.

We offer well-designed metallic nanoparticles with various functional groups. Clients may select the material type, particle size, size distribution, and/or surface functional groups such as carboxyl. And we also provide custom services for designing and synthesizing metallic nanoparticles with special required drugs loading, together with its analysis and characterization before and after drug encapsulation.

Quotations and Ordering

References

1. Vicky V. Mody, et al. Introduction to metallic nanoparticles. J Pharm Bioallied Sci. 2010,2(4): 282–289.
2. Xiaorong Song, et al. Functionalization of Metal Nanoclusters for Biomedical Applications. The Analyst, 2016, 141(11).
3. Dykman LA, Khlebtsov NG. Gold nanoparticles in biology and medicine: recent advances and prospects. Acta Naturae. 2011, 3(2):34-55.
4. Zhang D, et al.; Green Synthesis of Metallic Nanoparticles and Their Potential Applications to Treat Cancer. Front Chem. 2020, 8:799.