Viral Nanoparticles Research Articles

Vector-Free Deep Tissue Targeting of DNA/RNA Therapeutics via Single Capacitive Discharge Conductivity-Clamped Gene Electrotransfer.

Viral vector and lipid nanoparticle based gene delivery have limitations around spatiotemporal control, transgene packaging size, and vector immune reactivity, compromising translation of nucleic acid (NA) therapeutics. In the emerging field of DNA and particularly RNA-based gene therapies, vector-free delivery platforms are identified as a key unmet need. Here, this work addresses these challenges through gene electrotransfer (GET) of "naked" polyanionic DNA/mRNA using a single needle form-factor which supports "electro-lens" based compression of the local electric field, and local control of tissue conductivity, enabling single capacitive discharge minimal charge gene delivery. Proof-of-concept studies for "single capacitive discharge conductivity-clamped gene electrotransfer" (SCD-CC-GET) deep tissue delivery of naked DNA and mRNA in the mouse hindlimb skeletal muscle achieve stable (>18 month) expression of luciferase reporter synthetic DNA, and mRNA encoding the reporter yield rapid onset (<3 h) high transient expression for several weeks. Delivery of DNAs encoding secreted alkaline phosphatase and Cal/09 influenza virus hemagglutinin antigen generate high systemic circulating recombinant protein levels and antibody titres. The findings support adoption of SCD-CC-GET for vaccines and immunotherapies, and extend the utility of this technology to meet the demand for efficient vector-free, precision, deep tissue delivery of NA therapeutics.

Stem Cell in Breast Cancer Theraphy

There is a lot of research to support that cancer stem cell attract normal stem cell. The tendency of tumor cells to attract stem cells then becomes the basis for the use of stem cells in breast cancer theraphy. When neural stem cell applied as a carrier, it will make the amount, timing, and location of viral oncolytic or drug release can be precisely controlled. Finally, this situation will increase the effectiveness of breast cancer therapy and reduce side effects. This is a brief review about potency of stem cell as breast cancer treatment. This article aim to increased our knowledge about the potency of stem cell as breast cancer treatment. The tendency of tumor cells to attract stem cells then becomes the basis for the use of stem cells as enzyme/prodrug theraphy, secreted agent, viral oncolytic carrier or nanoparticle (drug) carrier which tends to be more localized around the tumor. When neural stem cell applied as a carrier, it will make the location, amount and timing of drug release or viral oncolytic can be precisely controlled.

Systemic administration of a viral nanoparticle neoadjuvant prevents lung metastasis development through emergency myelopoiesis

ABSTRACT Cancer presents a significant public health concern, particularly in the context of metastatic disease. Surgical removal of primary tumors, while essential, can inadvertently heighten the risk of metastasis. Thus, there is a critical need for innovative neoadjuvant therapies capable of curtailing metastatic progression before or immediately following tumor resection. Addressing this imperative, the papaya mosaic virus nanoparticle (PapMV) has demonstrated potent immunostimulatory capabilities against both viruses and tumors, effectively hindering their proliferation. Our study reveals that PapMV exerts a protective effect against lung metastasis when administered systemically prior to tumor implantation or during the early stages of metastasis in various mouse models of cancer. This anti-tumor effect is initiated by the recruitment of myeloid cells in the lungs. These cells adopt a pro-inflammatory profile, secreting cytokines such as IFN-α, thus fostering a tumor microenvironment inhospitable to tumor progression. Crucially, this protective mechanism hinges on the presence of macrophages before treatment. TLR7 and IFN-I signaling pathways also play pivotal roles in this process. Furthermore, our findings demonstrate that PapMV triggers the activation of the bone marrow emergency response, which accounts for the influx of myeloid cells into the lungs. This study unveils a novel aspect of PapMV’s functionality. By bolstering the immune system, PapMV confers robust protection against metastasis at an early stage of disease progression. This discovery holds promise for therapeutic intervention, particularly as a preemptive measure prior to or just after surgical intervention.

Application of Nanoparticles for Immunotherapy of Allergic Rhinitis.

Allergen Immunotherapy (AIT) is the only etiological therapeutic method available for allergic rhinitis (AR). Currently, several options for AIT in the market, such as subcutaneous immunotherapy (SCIT) and sublingual immunotherapy (SLIT), have different routes of administration. These traditional methods have achieved encouraging outcomes in clinic. However, the side effects associated with these methods have raised the need for innovative approaches for AIT that improve safety, shorten the course of treatment and increase local drug concentration. Nanoparticles (NPs) are particles ranging in size from 1 to 100 nm, which have been hired as potential adjuvants for AIT. NPs can be employed as agents for modulating immune responses in AR or/and carriers for loading proteins, peptides or DNA molecules. This review focuses on different kinds of nanoparticle delivery systems, including chitosan nanoparticles, exosomes, metal nanoparticles, and viral nanoparticles. We summarized the advantages and limitations of NPs for the treatment of allergic rhinitis. Overall, NPs are expected to be a therapeutic option for AR, which requires more in-depth studies and long-term therapeutic validation.

Exploring RNA therapeutics for urea cycle disorders.

RNA has triggered a significant shift in modern medicine, providing a promising way to revolutionize disease treatment methods. Different therapeutic RNA modalities have shown promise to replace, supplement, correct, suppress, or eliminate the expression of a targeted gene. Currently, there are 22 RNA-based drugs approved for clinical use, including the COVID-19 mRNA vaccines, whose unprecedented worldwide success has meant a definitive boost in the RNA research field. Urea cycle disorders (UCD), liver diseases with high mortality and morbidity, may benefit from the progress achieved, as different genetic payloads have been successfully targeted to liver using viral vectors, N-acetylgalactosamine (GalNAc) conjugations or lipid nanoparticles (LNP). This review explores the potential of RNA-based medicines for UCD and the ongoing development of applications targeting specific gene defects, enzymes, or transporters taking part in the urea cycle. Notably, LNP-formulated mRNA therapy has been assayed preclinically for citrullinemia type I (CTLN1), adolescent and adult citrin deficiency, argininosuccinic aciduria, arginase deficiency and ornithine transcarbamylase deficiency, in the latter case has progressed to the clinical trials phase.

Harnessing Epigenetic Mechanisms to Overcome Immune Evasion in Cancer: The Current Strategies and Future Directions.

Combining epigenetic alterations with cancer immunotherapy offers a promising approach to improve therapeutic outcomes by targeting the complex biology of tumors. Epigenetic mechanisms such as DNA methylation, histone modifications, and non-coding RNAs (ncRNAs) play a dual role in maintaining immune homeostasis and promoting cancer progression. Changes like hypomethylation in tumor cells can contribute to immune evasion and treatment resistance. Advances in epigenetic tools, particularly clustered regularly interspaced short palindromic repeat (CRISPR) and their associated protein (Cas9)-based epigenetic editing, allow for precise gene expression control, opening new avenues for research and therapy. The improved accuracy of CRISPR/dCas9 systems, when paired with appropriate delivery methods such as viral vectors or nanoparticles, has facilitated innovative combination therapies involving immune checkpoint inhibitors and epigenetic drugs. These combinations enhance the immune system's ability to recognize and destroy cancer cells. Despite these advancements, challenges like off-target effects, delivery issues, and resistance remain. Current research is focused on identifying new therapeutic targets, improving delivery systems, and using real-time feedback to refine treatment. Overall, combining immunotherapy with epigenetic modifications holds significant potential for personalized cancer treatment, paving the way for more effective and individualized therapeutic strategies that target both the immune system and the tumor microenvironment. Further development in this area is expected to revolutionize cancer therapy and improve patient outcomes.

Immunity and Protective Efficacy of a Plant-Based Tobacco Mosaic Virus-like Nanoparticle Vaccine against Influenza a Virus in Mice.

The rapid production of influenza vaccines is crucial to meet increasing pandemic response demands. Here, we developed plant-made vaccines comprising centralized consensus influenza hemagglutinin (HA-con) proteins (H1 and H3 subtypes) conjugated to a modified plant virus, tobacco mosaic virus (TMV) nanoparticle (TMV-HA-con). We compared immune responses and protective efficacy against historical H1 or H3 influenza A virus infections among TMV-HA-con, HA-con protein combined with AddaVax™ adjuvant, and whole-inactivated virus vaccine (Fluzone®). Immunogenicity studies demonstrated robust IgG, IgM, and IgA responses in the TMV-HA-con and HA-con protein vaccinated groups, with relatively low induction of interferon (IFN)-γ+ T-cell responses across all vaccinated groups. The TMV-HA-con and HA-con protein groups displayed partial protection (100% and 80% survival) with minimal weight loss following challenge with two H1N1 strains. The HA-con protein group exhibited 80% and 100% survival against two H3 strains, whereas the TMV-HA-con groups showed reduced protection (20% survival). The Fluzone® group conferred 20-100% survival against two H1N1 strains and one H3N1 strain, but did not protect against H3N2 infection. Our findings indicate that TMV-HA and HA-con protein vaccines with adjuvant induce protective immune responses against influenza A virus infections. Furthermore, our results underscore the potential of plant-based production using TMV-like nanoparticles for developing influenza A virus candidate vaccines.

An Abscopal Effect on Lung Metastases in Canine Mammary Cancer Patients Induced by Neoadjuvant Intratumoral Immunotherapy with Cowpea Mosaic Virus Nanoparticles and Anti-Canine PD-1.

Neoadjuvant intratumoral (IT) therapy could amplify the weak responses to checkpoint blockade therapy observed in breast cancer (BC). In this study, we administered neoadjuvant IT anti-canine PD-1 therapy (IT acPD-1) alone or combined with IT cowpea mosaic virus therapy (IT CPMV/acPD-1) to companion dogs diagnosed with canine mammary cancer (CMC), a spontaneous tumor resembling human BC. CMC patients treated weekly with acPD-1 (n = 3) or CPMV/acPD-1 (n = 3) for four weeks or with CPMV/acPD-1 (n = 3 patients not candidates for surgery) for up to 11 weeks did not experience immune-related adverse events. We found that acPD-1 and CPMV/acPD-1 injections resulted in tumor control and a reduction in injected tumors in all patients and in noninjected tumors located in the ipsilateral and contralateral mammary chains of treated dogs. In two metastatic CMC patients, CPMV/acPD-1 treatments resulted in the control and reduction of established lung metastases. CPMV/acPD-1 treatments were associated with altered gene expression related to TLR1-4 signaling and complement pathways. These novel therapies could be effective for CMC patients. Owing to the extensive similarities between CMC and human BC, IT CPMV combined with approved anti-PD-1 therapies could be a novel and effective immunotherapy to treat local BC and suppress metastatic BC.

High Cellular Internalization of Virus-Like Mesoporous Silica Nanoparticles Enhances Adaptive Antigen-Specific Immune Responses against Cancer.

Effective activation of an antigen-specific immune response hinges upon the intracellular delivery of cancer antigens to antigen-presenting cells (APCs), marking the initial stride in cancer vaccine development. Leveraging biomimetic topological morphology, we employed virus-like mesoporous silica nanoparticles (VMSNs) coloaded with antigens and toll-like receptor 9 (TLR9) agonists to craft a potent cancer vaccine. Our VMSNs could be efficiently internalized by APCs to a greater extent than their nonviral structured counterparts, thereby promoting the activation of APCs by upregulating the TLR9 pathway and cross-presenting ovalbumin (OVA) epitopes. In in vivo animal study, VMSN-based nanovaccines triggered substantial CD4+ and CD8+ lymphocyte populations in both lymph nodes and spleen while inducing the effector memory of adaptive T cells. Consequently, VMSN-based nanovaccines suppressed tumor progression and increased the survival rate of B16-OVA-bearing mice in both prophylactic and therapeutic studies. The combination of immune checkpoint blockade (ICB) with the VMSN-based nanovaccine has synergistic effects in significantly preventing tumor progression under therapeutic conditions. These findings highlight the potential of viral structure-mimicking mesoporous silica nanoparticles as promising candidates for antigen-delivering nanocarriers in vaccine development.

Enhanced Efficacy of a TLR3 Agonist Delivered by Cowpea Chlorotic Mottle Virus Nanoparticles

Enhanced Efficacy of a TLR3 Agonist Delivered by Cowpea Chlorotic Mottle Virus Nanoparticles

Magnetically Induced Thermal Effects on Tobacco Mosaic Virus-Based Nanocomposites for a Programmed Disassembly of Protein Cages.

Protein cages are promising tools for the controlled delivery of therapeutics and imaging agents when endowed with programmable disassembly strategies. Here, we produced hybrid nanocomposites made of tobacco mosaic virus (TMV) and magnetic iron oxide nanoparticles (IONPs), designed to disrupt the viral protein cages using magnetically induced release of heat. We studied the effects of this magnetic hyperthermia on the programmable viral protein capsid disassembly using (1) elongated nanocomposites of TMV coated heterogeneously with magnetic iron oxide nanoparticles (TMV@IONPs) and (2) spherical nanocomposites of polystyrene (PS) on which we deposited presynthesized IONPs and TMV via layer-by-layer self-assembly (PS@IONPs/TMV). Notably, we found that the extent of the disassembly of the protein cages is contingent upon the specific absorption rate (SAR) of the magnetic nanoparticles, that is, the heating efficiency, and the relative position of the protein cage within the nanocomposite concerning the heating sources. This implies that the spatial arrangement of components within the hybrid nanostructure has a significant impact on the disassembly process. Understanding and optimizing this relationship will contribute to the critical spatiotemporal control for targeted drug and gene delivery using protein cages.

Recent Therapeutic Gene Editing Applications to Genetic Disorders.

Recent years have witnessed unprecedented progress in therapeutic gene editing, revolutionizing the approach to treating genetic disorders. In this comprehensive review, we discuss the progression of milestones leading to the emergence of the clustered regularly interspaced short palindromic repeats (CRISPR)-based technology as a powerful tool for precise and targeted modifications of the human genome. CRISPR-Cas9 nuclease, base editing, and prime editing have taken center stage, demonstrating remarkable precision and efficacy in targeted ex vivo and in vivo genomic modifications. Enhanced delivery systems, including viral vectors and nanoparticles, have further improved the efficiency and safety of therapeutic gene editing, advancing their clinical translatability. The exploration of CRISPR-Cas systems beyond the commonly used Cas9, such as the development of Cas12 and Cas13 variants, has expanded the repertoire of gene editing tools, enabling more intricate modifications and therapeutic interventions. Outstandingly, prime editing represents a significant leap forward, given its unparalleled versatility and minimization of off-target effects. These innovations have paved the way for therapeutic gene editing in a multitude of previously incurable genetic disorders, ranging from monogenic diseases to complex polygenic conditions. This review highlights the latest innovative studies in the field, emphasizing breakthrough technologies in preclinical and clinical trials, and their applications in the realm of precision medicine. However, challenges such as off-target effects and ethical considerations remain, necessitating continued research to refine safety profiles and ethical frameworks.

Enhanced Efficacy of a TLR3 Agonist Delivered by Cowpea Chlorotic Mottle Virus Nanoparticles

Intratumoral immunotherapies are those that are administered directly into a tumor to remodel the local tumor microenvironment and stimulate systemic anti‐tumor immunity. Small molecule toll‐like receptor (TLR) agonists are undergoing development as intratumoral immunotherapies, and here the TLR3 agonist poly(I:C) is considered. Because small molecule therapeutics often suffer rapid washout effects and ineffective immune cell uptake, poly(I:C) is encapsulated into nanoparticles derived from cowpea chlorotic mottle virus (CCMV). The particles (but not the separate components) stimulate the activity of macrophages in vitro and are able to reduce tumor growth and prolong survival in mouse models of colon cancer and melanoma. CCMV‐poly(I:C) is also combined with oxaliplatin and found the combination therapy to be even more potent, strongly inhibiting tumor growth and increasing survival. The analysis of immune markers reveals that CCMV‐poly(I:C) VLPs with oxaliplatin promoted the infiltration and activation of CD4+ and CD8+ cells and the production of IL‐4 and IFN‐γ, indicating a synergistic immunogenic effect. The combined treatment also enhances the rate of apoptosis and immunogenic cell death (ICD). The data support the development of combination therapies involving immunomodulatory plant virus nanoparticles and antineoplastic drugs to attack tumors directly and via the activation of innate and adaptive immune responses.

A Multifunctionalized Potyvirus-Derived Nanoparticle That Targets and Internalizes into Cancer Cells.

Plant viral nanoparticles (VNPs) are attractive to nanomedicine researchers because of their safety, ease of production, resistance, and straightforward functionalization. In this paper, we developed and successfully purified a VNP derived from turnip mosaic virus (TuMV), a well-known plant pathogen, that exhibits a high affinity for immunoglobulins G (IgG) thanks to its functionalization with the Z domain of staphylococcal Protein A via gene fusion. We selected cetuximab as a model IgG to demonstrate the versatility of this novel TuMV VNP by developing a fluorescent nanoplatform to mark tumoral cells from the Cal33 line of a tongue squamous cell carcinoma. Using confocal microscopy, we observed that fluorescent VNP-cetuximab bound selectively to Cal33 and was internalized, revealing the potential of this nanotool in cancer research.

Abstract 7257: Examining the promise of precision medicine in immuno-oncology: Vectors for targeted therapeutic delivery

Abstract At the forefront of therapeutic delivery is an array of vectors and targeting methods that hold immense promise for precision medicine. Vehicles such as viral vectors (AAV and lentivirus), lipid nanoparticles (LNPs) or liposomes, and peptide micelles each possess distinct and inherent properties, empowering researchers with tools to navigate the intricate challenges of specificity and efficiency in drug transport. Herein, we discuss and demonstrate design principles underpinning these vectors, elucidating their unique mechanisms for targeted delivery including:- A high-throughput viral packaging process to enable rapid downstream CRISPR or shRNA screening- Proprietary AAV plasmid synthesis and preparation techniques to maintain ITR integrity and improve gene delivery- Rapid synthesis, in vitro transcription, and novel sequencing of mRNA constructs for complete characterization of critical components such as the polyA tailBy synthesizing advancements in vector technologies, this poster serves as a roadmap for researchers and practitioners navigating the evolving landscape of targeted drug delivery in immuno-oncology. Citation Format: Crystal Richardson, Prassanna Rao, Cassandra Koole, Michael J. Karney, Sumit Kumar. Examining the promise of precision medicine in immuno-oncology: Vectors for targeted therapeutic delivery [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 7257.

Abstract 351: Quaratusugene ozeplasmid mediated TUSC2 upregulation in EML4-ALK bearing non-small cell lung carcinoma can induce cellular apoptosis

Abstract Anaplastic Lymphoma Kinase (ALK), a potent oncogenic driver in Non-Small Cell Lung Carcinoma (NSCLC), is found to be rearranged and fused to Echinoderm microtubule-associated protein-like 4 (EML4), contributing to approximately 5% of NSCLC as a distinct clinicopathological subset. Tumors bearing the EML4-ALK fusion are sensitive to ALK Tyrosine Kinase Inhibitors (TKIs), that form the first and second line of treatment for these patients. However, ALK+ lung cancers develop resistance to ALK inhibitors, creating the need for newer treatment strategies in ALK+ NSCLC. Tumor Suppressor Candidate 2 (TUSC2) is a tumor suppressor gene that is known to have low endogenous expression in NSCLC in general but data on TUSC2 in ALK+ lung cancers are not available. Quaratusugene ozeplasmid, developed by Genprex, is an immunogene therapy that upregulates TUSC2 expression in cancer cells by delivering the functional TUSC2 gene. It consists of the TUSC2 gene expressing plasmid encapsulated in non viral lipid nanoparticles. We evaluated TUSC2 expression in 3 ALK+ cell lines, both before and after exposure to quaratusugene ozeplasmid and to a TUSC2-containing plasmid. Controls were non-ALK+ cell lines and transfection with a plasmid containing no insert. Our studies in ALK+ lung cancer reveal that overexpressing TUSC2 using quaratusugene ozeplasmid treatment of ALK+ lung cancer cell lines is able to suppress colony formation by 50%, the effect being more significant than using a TUSC2-containing plasmid. Furthermore, we have observed a robust pro-apoptotic response to TUSC2 expression in ALK+ NSCLC, as both quaratusugene ozeplasmid and TUSC2-containing plasmid induced an increase in caspase 3/7 activity in the cancer cells, accompanied by an increase in cleaved PARP expression. Taken together, our data indicate that overexpression of TUSC2 in ALK+ NSCLC cell lines with quaratusugene ozeplasmid or with TUSC2-containing plasmid is effective in decreasing growth and proliferation through the activation of apoptotic pathways and warrants further investigation as an anti-ALK NSCLC strategy. Citation Format: Ananya Banerjee, Neeke Busette, Mark S. Berger, Matthew B. Soellner, Angel Qin, Sofia D. Merajver, Nathan M. Merrill. Quaratusugene ozeplasmid mediated TUSC2 upregulation in EML4-ALK bearing non-small cell lung carcinoma can induce cellular apoptosis [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 351.

Abstract 497: Plant viruses against cancer

Abstract Immunotherapy has significantly transformed the landscape of cancer treatment; however, concerns about safety, efficacy, and long-term outcomes across various tumor types persist. We have developed an intratumoral immunotherapy strategy with an engineered plant virus nanotechnology and demonstrated efficacy in tumor mouse models and canine cancer patients. This method is designed to elicit a systemic (abscopal effect), safe, and enduring anti-tumor immune response that is not limited by tumor type. The power of immunotherapy lies in synergistic combination treatments and toward this goal, we are engineering the next-generation plant virus nanotechnologies. We demonstrate synergistic combination with chemotherapy and immunization strategies the hone in on tumor-associated antigens and key players of inflammation. The combinatorial immunotherapy strategies prevent recurrence post-surgery in mice and canine patients. We will discuss the engineering design principles leading toward synergetic combination immunotherapies to treat and prevent cancer; efficacy studies and underlying mechanism is elucidated through immunomics studies. Selected references: Steinmetz N.F. et al (2023) Viral nanoparticle vaccines against S100A9 reduce lung tumor seeding and metastasis. Proc. Natl. Acad. Sci. U.S.A. 120 (43) e2221859120. Wang C. and Steinmetz N.F. (2020) A Combination of Cowpea mosaic virus and Immune Checkpoint Therapy Synergistically Improves Therapeutic Efficacy in Three Tumor Models. Advanced Functional Materials, 2002299. Citation Format: Nicole F. Steinmetz, Young Hun Chung, Miguel Moreno-Gonzalez, Zhongchao Zhao. Plant viruses against cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 497.

A Combination of Flexible Modified Plant Virus Nanoparticles Enables Additive Effects Resulting in Improved Osteogenesis.

Plant virus nanoparticles (VNPs) genetically engineered to present osteogenic cues provide a promising method for biofunctionalizing hydrogels in bone tissue engineering. Flexible Potato virus X (PVX) nanoparticles substantially enhance the attachment and differentiation of human mesenchymal stem cells (hMSCs) by presenting the RGD motif, hydroxyapatite-binding peptide (HABP), or consecutive polyglutamates (E8) in a concentration-dependent manner. Therefore, it is hypothesized that Tobacco mosaic virus nanoparticles, which present 1.6 times more functional peptides than PVX, will meliorate such an impact. This study hypothesizes that cultivating hMSCs on a surface coated with a combination of two VNPs presenting peptides for either cell attachment or mineralization can achieve additionally enhancing effects on osteogenesis. Calcium minerals deposited by differentiating hMSCs increases two to threefold for this combination, while the Alkaline Phosphatase activity of hMSCs grown on the PVX-RGD/PVX-HABP-coated surface significantly surpasses any other VNP combination. Superior additive effects are observed for the first time by employing a combination of VNPs with varying functionalities. It is found that the flexible VNP geometry plays a more critical role than the concentration of functional peptides. In conclusion, various peptide-presenting plant VNPs exhibit an additive enhancing effect offering significant potential for effectively functionalizing cell-containing hydrogels in bone tissue engineering.

2D‐Ordered Layers of Tomato Bushy Stunt Virus via Specific Binding

Plant viruses are perfect candidates for the construction of nanobiotechnological devices. When employed in intricate 2D or 3D architectures, a stable, ordered virus layer, as the foundational plane, is a prerequisite. In former investigations, Coulomb‐force‐assisted self‐assembly is utilized. However, these layers demonstrate instability in further processing in a solution. In this study, an innovative strategy for immobilizing tomato bushy stunt viral (TBSV) nanoparticles through specific binding is reported on. Genetically engineered TBSV nanoparticles with Strep‐Tag II side chains are anchored using surface‐immobilized Strep‐Tactin. Strep‐Tactin, an engineered type of streptavidin with a strong specific interaction with the Strep‐Tag II protein, is immobilized on a silicon wafer through 3‐aminopropyltriethoxyilane and maleimide functionalization. Herein, the investigation involves optimizing the viral concentration and the pH values of the viral solution, facilitating the achievement of an optimal distribution of viral nanoparticles without vacancies during immobilization. The Strep‐Tactin/Strep‐Tag II system significantly improves the coverage of viral particles on the silicon substrate compared to the direct immobilization onto the untreated silicon substrate. The formed layers exhibit remarkable stability, even under sonication. To validate the findings, scanning force microscopy serves as a critical tool for imaging.

Advancements in Nanopore Technology for Virus Detection

Background: The spread of infectious diseases caused by viruses is always a global concern to public health. Developing affordable, accurate, fast and effective technologies for virus detection is crucial in reducing virus transmission. A nanopore is a sensor that can identify target molecules at a single molecule level, often used for genome sequencing and early disease detection. Nanopores are classified in two types: biological nanopores, ideal for detecting viral nucleic acid sequences, and solid-state nanopores primarily used to detect viral particles. Methods: In this review, we first provide a brief overview of the properties and fundamental principles of these two types of the nanopore. Then, we focus on the application of nanopores in viral nucleic acid sequencing and the quantitative detection of viral nanoparticles. Additionally, we discuss new strategies combining nanopore sensors with other technologies, which greatly improve the sensing performance. Results: A literature review on the application of nanopores in controlling viral epidemics is provided. The pros and cons of biological nanopores and solid-state nanopores are summarized, respectively, and the opportunities of integrating novel technologies with nanopore sensors to enhance the latter are addressed in this paper. Conclusion: Owing to significant advancements in nanotechnology and integration with other technologies such as machine learning, nanopore sensors are becoming widely applied in virusesrelated analysis. In the long term, nanopore sensors are expected to play an important role in the field of virus detection and analysis.