Rapid and selective detection of viruses using virus-imprinted polymer films

Imprinting of nanoparticles in thin films: Quo Vadis?

Nanomaterials, and especially nanoparticles, have been introduced to almost any aspect of our lives. This has caused increasing concern as to their toxicity and adverse effects on the environment and human health. The activity of nanoparticles, including their nanotoxicity, is not only a function of the material they are made of but also their size, shape, and surface properties. It is evident that there is an unmet need for simple approaches to the speciation of nanoparticles, namely to monitor and detect them based on their properties. An appealing method for such speciation involves the imprinting of nanoparticles in soft matrices. The principles of imprinting nanoparticles originate from the molecularly imprinted polymer (MIP) approach. This review summarizes the current status of this emerging field, which bridges between the traditional MIP approach and the imprinting of larger entities such as viruses and bacteria. The concepts of nanoparticle imprinting and the requirement of both physical and chemical matching between the nanoparticles and the matrix are discussed and demonstrated.

Molecularly imprinted polymers for the detection of viruses: challenges and opportunities

Molecularly imprinted polymers (MIPs) have numerous applications in the sensing field, the detection/recognition of virus, the structure determination of proteins, drug delivery, artificial/biomimetic antibodies, drug discovery, and cell culturing. There are lots of conventional methods routinely deployed for the analysis/detection of viral infections and pathogenic viruses, namely enzyme immunoassays, immunofluorescence microscopy, polymerase chain reaction (PCR) and virus isolation. However, they typically suffer from higher costs, low selectivity/specificity, false negative/positive results, time consuming procedures, and inherent labor intensiveness. MIPs offer promising potential for viral recognition/detection with high target selectivity, sensitivity, robustness, reusability, and reproducible fabrication. In terms of virus detection, selectivity and sensitivity are critical parameters determined by the template; additionally, the analytical detection and evaluation of viruses must have considerably low detection limits. The virus-imprinted polymer-based innovative strategies with enough specificity, convenience, validity, and reusability features for the detection/recognition of a wide variety of viruses, can provide attractive capabilities for reliable screening with minimal false negative/positive results that is so crucial for the prevention and control of epidemic and pandemic viral infections. However, in the process of imprinting viruses, critical factors such as size of the target, solubility, fragility, and compositional complexity should be analytically considered and systematically evaluated. In this review, recent advancements regarding the applications of MIPs and pertinent virus imprinting techniques for the detection of viruses, as well as their current significant challenges and future perspectives, are deliberated.

An Overview of Bio-Inspired Intelligent Imprinted Polymers for Virus Determination

The molecular imprinting polymers (MIPs) have shown their potential in various applications including pharmaceuticals, chemical sensing and biosensing, medical diagnosis, and environmental related issues, owing to their artificial selective biomimetic recognition ability. Despite the challenges posed in the imprinting and recognition of biomacromolecules, the use of MIP for the imprinting of large biomolecular oragnism such as viruses is of huge interest because of the necessity of early diagnosis of virus-induced diseases for clinical and point-of-care (POC) purposes. Thus, many fascinating works have been documented in which such synthetic systems undoubtedly explore a variety of potential implementations, from virus elimination, purification, and diagnosis to virus and bacteria-borne disease therapy. This study is focused comprehensively on the fabrication strategies and their usage in many virus-imprinted works that have appeared in the literature. The drawbacks, challenges, and perspectives are also highlighted.

Label-Free Detection of Staphylococcus aureus Based on Bacteria-Imprinted Polymer and Turn-on Fluorescence Probes

The effective identification and quantitative determination of Staphylococcus aureus is a major public health concern. Here, an innovative strategy that combines a bacteria-imprinted polydimethylsiloxane film for bacterial recognition and fluorescence resonance energy transfer platform for turn-on fluorescence sensing is demonstrated. The bacteria-imprinted polydimethylsiloxane film was facilely fabricated to generate corresponding specific sites on the polydimethylsiloxane surface via stamp imprinting using Staphylococcus aureus as template followed by modification with 1H,1H,2H,2H-perfluorooctyltriethoxysilane. The fluorescence resonance energy transfer platform was developed through electrostatic interaction between citrate-functional copper clusters and dopamine-stabilized gold nanoparticles. When the Staphylococcus aureus are present, the 1H,1H,2H,2H-perfluorooctyltriethoxysilane-modified bacteria-imprinted polydimethylsiloxane film can precisely capture the target; subsequently, the negatively charged bacteria compete with citrate-functional copper clusters and bind to dopamine-stabilized gold nanoparticles, leading to the fluorescence recovery of citrate-functional copper clusters. The entire detection process was achieved within 135 min, showing a wide linear calibration response from 10 to 1 × 10⁷ cfu mL^-1 with a low detection limit of 11.12 cfu mL^-1. Furthermore, the recoveries from spiked samples were from 97.7 to 101.90% with relative standard derivations lower than 10%. The established label-free assay of measuring Staphylococcus aureus is rapid, sensitive, specific, and efficient.

Recent advances in lab-on-a-chip technologies for viral diagnosis

The global risk of viral disease outbreaks emphasizes the need for rapid, accurate, and sensitive detection techniques to speed up diagnostics allowing early intervention. An emerging field of microfluidics also known as the lab-on-a-chip (LOC) or micro total analysis system includes a wide range of diagnostic devices. This review briefly covers both conventional and microfluidics-based techniques for rapid viral detection. We first describe conventional detection methods such as cell culturing, immunofluorescence or enzyme-linked immunosorbent assay (ELISA), or reverse transcription polymerase chain reaction (RT-PCR). These methods often have limited speed, sensitivity, or specificity and are performed with typically bulky equipment. Here, we discuss some of the LOC technologies that can overcome these demerits, highlighting the latest advances in LOC devices for viral disease diagnosis. We also discuss the fabrication of LOC systems to produce devices for performing either individual steps or virus detection in samples with the sample to answer method. The complete system consists of sample preparation, and ELISA and RT-PCR for viral-antibody and nucleic acid detection, respectively. Finally, we formulate our opinions on these areas for the future development of LOC systems for viral diagnostics.

Rapid and selective recognition of Vibrio parahaemolyticus assisted by perfluorinated alkoxysilane modified molecularly imprinted polymer film

Molecular imprinting technology offers a means of tailor-made materials with high affinity and selectivity for certain analysts. However, the recognition and separation of specific bacteria in complex matrices are still challenging. Herein, a bacteria-imprinted polydimethylsiloxane (PDMS) film was facilely prepared and modified with 1H,1H,2H,2H-perfluorooctyltriethoxysilane (POTS). Employing Vibrio parahaemolyticus as a model bacterium, the imprinted surface exhibited three-dimensionality cavities with mean size of 1000 × 800 nm in square and 100 nm in depth. After incubation for 2 h with 6 × 10⁷ CFU mL⁻¹ of V. parahaemolyticus, the imprinted polymer film can reach a 62.9% capture efficiency. Furthermore, the imprinted POTS-modified PDMS film based solid phase extraction combined with polymerase chain reaction and agarose gel electrophoresis allows for detecting 10⁴ CFU mL⁻¹ with excellent selectivity in fresh oyster samples. As a result, the developed selective sample pretreatment method using molecular imprinting technology provides a promising platform for separation, identification, and analysis of pathogens.

Molecular imprinting technology offers a means of tailor-made materials with high affinity and selectivity for certain analysts.

Application of nanotechnology in biosensors for enhancing pathogen detection

Rapid detection and identification of pathogenic microorganisms is fundamental to minimizing the spread of infectious disease, and informing clinicians on patient treatment strategies. This need has led to the development of enhanced biosensors that utilize state of the art nanomaterials and nanotechnology, and represent the next generation of diagnostics. A primer on nanoscale biorecognition elements such as, nucleic acids, antibodies, and their synthetic analogs (molecular imprinted polymers), will be presented first. Next the application of various nanotechnologies for biosensor transduction will be discussed, along with the inherent nanoscale phenomenon that leads to their improved performance and capabilities in biosensor systems. A future outlook on characterization and quality assurance, nanotoxicity, and nanomaterial integration into lab-on-a-chip systems will provide the closing thoughts. This article is categorized under: Diagnostic Tools > Diagnostic Nanodevices Diagnostic Tools > Biosensing.

Bio-inspired virus imprinted polymer for prevention of viral infections

A novel virus-imprinted polymer for prevention of viral infection was prepared by anchoring molecularly imprinted polymer (MIP) on the surface of poly-dopamine (PDA)-coated silica particles. The imprinting reaction was carried out via self-polymerization of dopamine in the presence of a virus template. Plaque forming assay indicated that the MIP exhibited selective anti-viral infection properties for the template virus in complex media containing different interfering substances, and even other types of viruses. Remarkable dose-dependent and time-dependent inhibition of virus infection was observed due to the MIP's selective binding to the template virus. When the MIP was incubated with the virus and host cells together, rapid and selective adsorption of template viruses by the MIP prevented the viruses to infect the host cells in a period of 12h. The MIP was biocompatible and non-toxic, and had excellent stability and reusability. Furthermore, the MIPs prepared using different viruses as templates showed similar anti-viral infection properties. The MIP synthesized using dopamine as monomer and crude virus as template provided an attractive possibility for clinical applications in the field of antiviral therapy.

STATEMENT OF SIGNIFICANCE

This is the first report to prepare artificial antibody (molecularly imprinted polymer, MIP) that can selectively prevent virus infection using dopamine self-polymerization system. Only MIP anchoring on the surface of poly-dopamine coated silica particles and polymerized using ammonium persulfate as radical initiator showed dose-dependent and time-dependent inhibition of template virus infection in complex media containing interferences and even other viruses. Viruses bond to MIP lost infectious capability. When incubated with virus and host cells, MIP rebond viruses rapidly and selectively to prevent viruses infecting host cells for 12h. The achieved MIPs were biocompatibility, non-toxicity with excellent stability and reusability, and can be used to different viruses. The bio-mimic MIPs provided an attractive prospect for clinical applications in antiviral therapy.

Viruses, Artificial Viruses and Virus-Based Structures for Biomedical Applications

Nanobiomaterials such as virus particles and artificial virus particles offer tremendous opportunities to develop new biomedical applications such as drug- or gene-delivery, imaging and sensing but also improve understanding of biological mechanisms. Recent advances within the field of virus-based systems give insights in how to mimic viral structures and virus assembly processes as well as understanding biodistribution, cell/tissue targeting, controlled and triggered disassembly or release and circulation times. All these factors are of high importance for virus-based functional systems. This review illustrates advances in mimicking and enhancing or controlling these aspects to a high degree toward delivery and imaging applications.