Aptamer Conjugated Nanoparticles

With the rapid development of biomedical science, the need for accurate diagnosis and treatment is increasingly urgent. As a pioneer in biomedicine, BOC Sciences is focused on delivering cutting-edge aptamer conjugated nanoparticle technologies designed to enhance the accuracy and performance of a wide range of biomedical applications, from targeted therapy to molecular imaging to biosensing.

What is aptamer conjugated nanoparticle?

Aptamers, in short, are molecules made of short strands of DNA or RNA that fold into three-dimensional structures with specific recognition capabilities and bind tightly to specific target molecules with high affinity, ranging from proteins to small molecules and even cells. Because of their strong specificity, high plasticity and low immunogenicity, aptamers are known as "chemical antibodies" and show unparalleled potential in the biomedical field.

Nanoparticles, ranging in size from 1 to 100 nanometers, exhibit extraordinary physical and chemical properties due to their unique surface-to-volume ratio, making them ideal carriers for biomedical research. In the aptamer conjugated nanoparticle system, various materials such as gold, silica, liposome or polymer can be used to prepare nanoparticles, depending on the specific application requirements. For example, gold nanoparticles are popular for their ease of functionalization and unique optical properties; Polymer nanoparticles are known for their good biocompatibility and drug loading capacity. The aptamer is anchored to the surface of the nanoparticle in a stable and directional manner via a chemical connection bridge, ensuring that recognition is not impaired.

The conjugation of aptamers and nanoparticles can be achieved by covalent binding, electrostatic adsorption or avidin-biotin system. Covalent bonding, especially the use of amine or sulfhydryl strategies, ensures the stability and durability of the connection, which is particularly critical for in vivo applications. In contrast, electrostatic action is simple and fast, but the stability may be discounted in the physiological environment. Although avidin-biotin conjugating method has high specificity and stability, it may increase the process complexity and cost. We focus on implementing precise conjugating strategies to ensure efficient integration of aptamers and nanoparticles, creating best-in-class composite tools. This conjugation process is finely tuned to maintain the respective activity and synergies of the aptamer and nanoparticle to maximize overall performance.

Fig.1 Some aptamer conjugated nanoparticles. (Park, D., 2024)

Advantages of aptamer conjugated nanoparticles

The targeting ability of aptamers

Aptamers are a class of single-stranded DNA or RNA molecules screened by SELEX technology that can specifically recognize and bind to specific molecules or cell surface receptors, such as proteins that are overexpressed on the surface of tumor cells. Through chemical modifications, the stability and biological activity of the aptamer can be adjusted to suit different delivery needs.

Carrier advantages of nanoparticles

Nanoparticles have a large surface area and volume ratio and can effectively load multiple drugs or biomolecules.

Such as gold nanoparticles (AuNPs), mesoporous silica nanoparticles (MSNs), etc., have good biocompatibility, and can be functionalized on the surface to facilitate labeling of aptamers.

The nanoparticles are the right size and can penetrate biological barriers, such as the blood-brain barrier, to improve delivery efficiency.

Application of aptamer conjugated nanoparticles

Targeted drug delivery

One of the most promising applications of aptamer-conjugated nanoparticles is targeted drug delivery. Traditional drug delivery methods often lack specificity, resulting in systemic side effects and reduced therapeutic effectiveness. Aptamer conjugated nanoparticles can solve these problems by delivering drugs directly to the disease site. Aptamers act as targeting ligands that recognize and bind to specific biomarkers on the surface of diseased cells. Once combined, the nanoparticles can release their drug payload in a controlled manner, ensuring that the therapeutic agent is concentrated at the target, minimizing off-target effects, and enhancing therapeutic effectiveness.

Molecular imaging

In the field of molecular imaging, aptamer conjugated nanoparticles offer significant advances. These conjugates can be designed to carry imaging agents, such as fluorescent dyes or radioisotopes, enabling precise visualization of biological processes at the molecular level. For example, in cancer diagnosis, aptamer-conjugated nanoparticles can be used to target and highlight tumor cells, providing high-resolution images that promote early detection and accurate staging of disease.

Biosensing and diagnostics

Aptamer conjugated nanoparticles are also revolutionizing the field of biosensing and diagnostics. Their high specificity and binding affinity make them excellent candidates for detecting various biomarkers associated with disease. In biosensors, the combination of target molecules with aptamer-nanoparticle conjugates can induce measurable signal changes, such as changes in fluorescence or electrochemical response, enabling fast and sensitive detection. This ability is especially valuable in point-of-care diagnostics, where fast and accurate results are critical.

Therapeutic application

In addition to diagnosis and imaging, aptamer conjugated nanoparticles have great potential for therapeutic applications. In cancer therapy, for example, these conjugates could be used to deliver not only chemotherapy drugs, but also gene-silencing molecules like siRNA. This versatile approach allows for a coordinated attack on cancer cells while inhibiting tumor growth and inducing cell death through different mechanisms.

Concrete applications of aptamer conjugated nanoparticles

Aptamer-gold nanoparticle conjugation: For example, the nanoparticle drug delivery system (Apt-Dox-CS-Au-5FU NPs) developed by Sathiyaseelan et al., which is composed of gold nanoparticles, chitosan and aptamers, can specifically target cells that overexpress nucleolin to achieve effective drug delivery.

Mesoporous silicon dioxide nanoparticles (MSNs): Xie et al. constructed MSN-SS-siTIE2/Apt@DOX drug delivery system, and used mercaptoyl covalently to connect AS1411 aptamer and siTIE2 to release drugs through REDOX response, effectively inhibiting breast cancer metastasis.

RNA/DNA nanoparticles: The DNA-programmed SNA (PSNA) system designed by Li et al. realized the targeted delivery and treatment of HER2+ breast cancer cells by covalently connecting HER2 aptamer, XBP1 siRNA and AuNPs.

Our aptamer conjugated nanoparticles services

Custom aptamer selection and synthesis

The core of constructing efficient aptamer conjugated nanoparticles is the high performance aptamer. We rely on cutting-edge SELEX technology (phylogenetic ligand through exponential enrichment) to precisely locate and synthesize aptamers with exceptional specificity and high affinity. This process not only ensures the stability of the aptamer, but also optimizes it specifically for its intended application scenarios, whether for specific cancer cells, bacterial pathogens, or other biomarkers, ensuring maximum effectiveness.

Precision design and functionalization of nanoparticles

Precise design of nanoparticles is as critical as functionalization. Our team of nanotechnology experts carefully creates nanocarriers that perfectly match the selected aptamer, ensuring that the payload reaches its target precisely. We specialize in the customization of various nanomaterials such as gold nanoparticles, magnetic nanoparticles, liposomes and polymer nanoparticles, adjusting their size, shape and surface properties according to customer requirements to achieve highly personalized customized services.

Advanced conjugation strategies and optimization

The selection and optimization of conjugation strategies directly affect the performance of ligand-nanoparticle complexes. We use advanced conjugation techniques to ensure a stable and efficient bond between the aptamer and the nanoparticle, while preserving the biological activity of the aptamer and enhancing the overall stability of the complex. We use a variety of strategies, including covalent bonding, electrostatic interaction and click chemistry, to achieve the best conjugation effect.

Comprehensive in vivo and in vitro validation system

To verify the actual performance of aptamer conjugated nanoparticles, we perform a rigorous in vitro and in vivo testing process. Relying on advanced laboratory equipment, we conduct a wide range of analyses involving cell viability analysis, binding affinity assessment, endocytosis mechanism studies, and evaluation of therapeutic effects using animal models. This series of rigorous validation steps is designed to ensure that our conjugations have fully demonstrated their safety, specificity and therapeutic effectiveness before entering clinical application, laying a solid foundation for the transformation of scientific research results.

The advantages of our aptamer conjugated nanoparticles service are its high level of target specificity, precise delivery capabilities and strong multi-functional potential. With precisely designed aptamers, our nanoparticles can accurately identify and bind to target molecules, enabling efficient delivery of drugs or diagnostic reagents. At the same time, our technology platform supports a variety of functional modifications of nanoparticles, so that they can meet the needs of different application scenarios, and provide strong support for research and development in the field of biomedicine.

FAQ

1. What are aptamer conjugated nanoparticles?

Aptamer conjugated nanoparticles are nanoparticles that have been functionalized with aptamers. Aptamers are short, single-stranded oligonucleotides (DNA or RNA) that can bind to specific targets with high affinity and specificity, similar to antibodies. These conjugated nanoparticles can be used for targeted drug delivery, diagnostics, and theranostics.

2. What applications can benefit from aptamer-conjugated nanoparticles?

• Targeted drug delivery
• Diagnostic imaging
• Biosensing
• Cancer therapy
• Infectious disease treatment

3. How are the nanoparticles synthesized and conjugated with aptamers?

Our team uses state-of-the-art technologies to synthesize nanoparticles from various materials such as gold, silver, silica, and polymers. The aptamers are then conjugated to these nanoparticles using established chemical methods that ensure stable and efficient binding, maintaining the functionality of both the nanoparticle and the aptamer.

4. What are the advantages of using aptamer-conjugated nanoparticles over traditional methods?

• High specificity and affinity to target molecules or cells
• Reduced off-target effects
• Stability under physiological conditions
• Ability to penetrate tissues and cells effectively

5. Can you provide custom conjugation services if we have specific requirements?

Yes, we offer custom conjugation services tailored to meet our clients' specific needs. You can provide your own aptamers or targets, and we will work closely with you to optimize the conjugation process to ensure the desired performance.

6. What type of characterization and quality control do you perform?

• Size and charge distribution (DLS, Zeta potential)
• Structural analysis (SEM, TEM)
• Surface chemistry verification (FTIR, XPS)
• Binding affinity (Biolayer Interferometry, SPR)
• Functional assays (in vitro and in vivo)