Aptamers: an emerging class of bioaffinity ligands in bioactive peptide applications

Selection and identification of an ssDNA aptamer against influenza B virus hemagglutinin protein

BACKGROUND

The influenza virus causes infectious respiratory disease with high morbidity and mortality worldwide. Influenza B typically goes unnoticed owing to its mild clinical symptoms and limitations. However, its increasing prevalence in recent years poses a significant health burden. Consequently, current diagnostic methods for the detection of influenza B virus are inadequate, highlighting the urgent need to develop accurate and sensitive techniques for early disease diagnosis. Aptamers, single-stranded deoxyribonucleic acid (ssDNA), or ribonucleic acid molecules primarily rely on their secondary structures, such as stem-loops and hairpins, to bind efficiently and specifically to the target through base complementary pairing, electrostatic interaction, hydrogen bonding, and van der Waals forces. Aptamers are superior to antibodies in their ability to bind targets. The objective of this study was to identify and develop aptamers against the hemagglutinin (HA) protein of influenza B virus.

METHODS

An enriched DNA library with strong binding to the influenza B virus HA protein was obtained using magnetic bead systematic evolution of ligands by exponential enrichment technology after nine rounds of selection. Five candidate aptamers were identified by high-throughput sequencing. The aptamers were characterized using surface plasmon resonance and enzyme-linked immunosorbent assay techniques, and the aptamer exhibiting the highest affinity and specificity for the target protein was selected.

RESULTS

We screened and characterized five ssDNA aptamer sequences that bind to influenza B virus HA. Among these, aptamer sequence A573 exhibited the highest sensitivity and binding affinity for the target protein.

CONCLUSIONS

The novel aptamer sequences selected in this study have the potential to be used as biorecognition molecules for the development of aptamer sensors to detect influenza B virus.

Specific DNA aptamer-immobilized cryogel membranes as novel bioaffinity supports and their potential for the purification of activated protein C

Activated protein C (APC), a serine protease produced from zymogen protein C (PC), is the key enzyme of the protein C pathway. APC has anticoagulant, anti-inflammatory, and cytoprotective features. APC has recently been shown to significantly reduce coagulation as well as mortality in patients with severe sepsis. Herein, we aimed to develop an affinity support material that allows the purification of plasma APC for the first time. In this research, a novel APC-specific DNA aptamer-based poly(2-hydroxyethyl methacrylate-glycidyl methacrylate) (poly(HEMA-GMA/DNA-Apt)) macroporous cryogel membrane at different molar ratios was prepared using affinity binding method and their potential for purification and identification of APC was investigated. The DNA aptamer-immobilized cryogels were characterized to examine their structural and morphological properties. The effect of pH, initial concentration, temperature, ionic strength difference, and flow rate changes was examined. Selectivity studies were performed in the presence of APC and competitive proteins, and cryogel support materials were shown to have a very high affinity for APC. Adsorption capacity was found to be 89.02 mg/g. Finally, NaCl revealed efficiency for APC desorption and the reuse of cryogels was successfully tested for ten cycles.

Exploiting the Specificity of CRISPR/Cas System for Nucleic Acids Amplification-Free Disease Diagnostics in the Point-of-Care

Rapid and reliable molecular diagnostics employing target nucleic acids and small biomarkers are crucial strategies required for the precise detection of numerous diseases. Although diagnoses based on nucleic acid recognition are some of the most efficient and precise procedures, these tests often require expensive equipment and skilled professionals. Recent advancements in diagnostic innovations, particularly those based on clustered regularly interspaced short palindromic repeats (CRISPR), aim to provide thorough screening at homes, in clinics, and in the field. In comparison to traditional molecular techniques like PCR, CRISPR/Cas-based detection, using the single-stranded nucleic acid trans-cleavage abilities of Cas12 or Cas13, shows significant potential as a molecular diagnostic tool. It offers benefits such as attomolar-level sensitivity, single-base precision, and rapid turnover rates. Both Cas enzymes demonstrate exceptional specificity and sensitivity, holding substantial promise in disease diagnostics and beyond. Consequently, various amplification-free CRISPR/Cas-based detection methods have emerged, aiming to maintain sensitivity despite the absence of pre-amplification. This allows for the detection of non-nucleic acid targets and facilitates integration into point-of-care settings. This Review highlights current advances in amplification-free CRISPR/Cas detection systems in disease diagnostics and investigates their utility in point-of-care settings. Furthermore, the mechanisms of alternative CRISPR-based amplification-free detection of other small molecules, aside from nucleic acids, for disease diagnosis will also be briefly discussed.

Designing molecules: directing stem cell differentiation

Stem cells have been widely applied in regenerative and therapeutic medicine for their unique regenerative properties. Although much research has shown their potential, it remains tricky in directing stem cell differentiation. The advancement of genetic and therapeutic technologies, however, has facilitated this issue through development of design molecules. These molecules are designed to overcome the drawbacks previously faced, such as unexpected differentiation outcomes and insufficient migration of endogenous or exogenous MSCs. Here, we introduced aptamer, bacteriophage, and biological vectors as design molecules and described their characteristics. The methods of designing/developing discussed include various Systematic Evolution of Ligands by Exponential Enrichment (SELEX) procedures, in silico approaches, and non-SELEX methods for aptamers, and genetic engineering methods such as homologous recombination, Bacteriophage Recombineering of Electroporated DNA (BRED), Bacteriophage Recombineering with Infectious Particles (BRIP), and genome rebooting for bacteriophage. For biological vectors, methods such as alternate splicing, multiple promoters, internal ribosomal entry site, CRISPR-Cas9 system and Cre recombinase mediated recombination were used to design viral vectors, while non-viral vectors like exosomes are generated through parental cell-based direct engineering. Besides that, we also discussed the pros and cons, and applications of each design molecule in directing stem cell differentiation to illustrate their great potential in stem cells research. Finally, we highlighted some safety and efficacy concerns to be considered for future studies.

Nanoscale Materials Applying for the Detection of Mycotoxins in Foods

Trace amounts of mycotoxins in food matrices have caused a very serious problem of food safety and have attracted widespread attention. Developing accurate, sensitive, rapid mycotoxin detection and control strategies adapted to the complex matrices of food is crucial for in safeguarding public health. With the continuous development of nanotechnology and materials science, various nanoscale materials have been developed for the purification of complex food matrices or for providing response signals to achieve the accurate and rapid detection of various mycotoxins in food products. This article reviews and summarizes recent research (from 2018 to 2023) on new strategies and methods for the accurate or rapid detection of mold toxins in food samples using nanoscale materials. It places particular emphasis on outlining the characteristics of various nanoscale or nanostructural materials and their roles in the process of detecting mycotoxins. The aim of this paper is to promote the in-depth research and application of various nanoscale or structured materials and to provide guidance and reference for the development of strategies for the detection and control of mycotoxin contamination in complex matrices of food.

Single-Walled Carbon Nanohorn-Based Fluorescence Energy Resonance Transfer Aptasensor Platform for the Detection of Aflatoxin B1

Aflatoxin B1 (AFB1) is one of the most contaminated fungal toxins worldwide and is prone to cause serious economic losses, food insecurity, and health hazards to humans. The rapid, on-site, and economical method for AFB1 detection is need of the day. In this study, an AFB1 aptamer (AFB1-Apt) sensing platform was established for the detection of AFB1. Fluorescent moiety (FAM)-modified aptamers were used for fluorescence response and quenching, based on the adsorption quenching function of single-walled carbon nanohorns (SWCNHs). Basically, in our constructed sensing platform, the AFB1 specifically binds to AFB1-Apt, making a stable complex. This complex with fluorophore resists to be adsorbed by SWCNHs, thus prevent SWCNHs from quenching of fluorscence, resulting in a fluorescence response. This designed sensing strategy was highly selective with a good linear response in the range of 10-100 ng/mL and a low detection limit of 4.1 ng/mL. The practicality of this sensing strategy was verified by using successful spiking experiments on real samples of soybean oil and comparison with the enzyme-linked immunosorbent assay (ELISA) method.

Aptamers Versus Vascular Endothelial Growth Factor (VEGF): A New Battle against Ovarian Cancer

Cancer is one of the diseases that causes a high mortality as it involves unregulated and abnormal cell growth proliferation that can manifest in any body region. One of the typical ovarian cancer symptoms is damage to the female reproductive system. The death rate can be reduced through early detection of the ovarian cancer. Promising probes that can detect ovarian cancer are suitable aptamers. Aptamers, i.e., so-called chemical antibodies, have a strong affinity for the target biomarker and can typically be identified starting from a random library of oligonucleotides. Compared with other probes, ovarian cancer targeting using aptamers has demonstrated superior detection effectiveness. Various aptamers have been selected to detect the ovarian tumor biomarker, vascular endothelial growth factor (VEGF). The present review highlights the development of particular aptamers that target VEGF and detect ovarian cancer at its earliest stages. The therapeutic efficacy of aptamers in ovarian cancer treatment is also discussed.

Editorial to the IJMS Special Issue "Aptamer-Mediated Cancer Theranostics"

Aptamers have emerged as a new generation of bioaffinity probes with enhanced target binding specificity and selectivity [...].

Stimuli-Activable Metal-Bearing Nanomaterials and Precise On-Demand Antibacterial Strategies

Bacterial infections remain the leading cause of death worldwide today. The emergence of antibiotic resistance has urged the development of alternative antibacterial technologies to complement or replace traditional antibiotic treatments. In this regard, metal nanomaterials have attracted great attention for their controllable antibacterial functions that are less prone to resistance. This review discusses a particular family of stimuli-activable metal-bearing nanomaterials (denoted as SAMNs) and the associated on-demand antibacterial strategies. The various SAMN-enabled antibacterial strategies stem from basic light and magnet activation, with the addition of bacterial microenvironment responsiveness and/or bacteria-targeting selectivity and therefore offer higher spatiotemporal controllability. The discussion focuses on nanomaterial design principles, antibacterial mechanisms, and antibacterial performance, as well as emerging applications that desire on-demand and selective activation (i.e., medical antibacterial treatments, surface anti-biofilm, water disinfection, and wearable antibacterial materials). The review concludes with the authors' perspectives on the challenges and future directions for developing industrial translatable next-generation antibacterial strategies.

Antifungal activity of montmorillonite/peptide aptamer nanocomposite against Colletotrichum gloeosporioides on Stylosanthes

Chemical agents are effective treatment methods for anthracnose induced by pathogenic Colletotrichum gloeosporioides on Stylosanthes. However, excess consumption of chemical agents destroys the environment, synthetic biology was capable of conquering the issue. The antifungal agent is developed by enclosing a bio-synthesized peptide aptamer with layered montmorillonite via electrostatic interaction. Compared with free peptide aptamer, the nanocomposite exhibits higher antifungal activity against Colletotrichum gloeosporioides, further improving the utilization of peptide aptamer. The nanocomposite killed Colletotrichum gloeosporioides by releasing peptide aptamer after they entered the spore. Moreover, montmorillonite enhances the adhesion ability of peptide aptamer via hydrophobic interactions between nanomaterials and leaves, prolonging the extension time of nanocomposite on leaves. Consequently, 0.1 mg of nanocomposite demonstrates a comparable effect to commercial carbendazim (1 %) to prevent anthracnose on leaves of Stylosanthes induced by HK-04 at room temperature. This work demonstrates an alternative to commercial antifungal agents and proposes a versatile approach to preparing environmental-friendly antifungal agents to inhibit fungal infections on crops.

Bioactive metabolites in functional and fermented foods and their role as immunity booster and anti-viral innate mechanisms

Live microorganisms in the fermented foods termed probiotics and their secondary metabolites with bioactive potential were considered as potential anti-viral capabilities through various mechanisms. Given the importance of functional and fermented foods in disease prevention, there is a need to discuss the contextualization and deep understanding of the mechanism of action of these foods, particularly considering the appearance of coronavirus (COVID-19) pandemic, which is causing health concerns and increased social services globally. The mechanism of probiotic strains or their bioactive metabolites is due to stimulation of immune response through boosting T-lymphocytes, cytokines, and cell toxicity of natural killer cells. Proper consumption of these functional and fermented foods may provide additional antiviral approaches for public benefit by modulating the immune functions in the hosts.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13197-022-05528-8.

A simple unlabeled human chorionic gonadotropin biosensor based on a peptide aptamer

As an essential biochemical indicator in the fields of pregnancy and oncology, human chorionic gonadotropin (HCG) can be evaluated using colloidal gold immunochromatographic paper and quantified using a biochemical analyzer based on the principle of the antibody sandwich method. In view of the inaccuracy of the former and the complication of the latter, this study constructed an accurate, sensitive and simple unlabeled biosensor based on peptide aptamer CGGGPPLRINRHILTR for HCG detection. Molecular Operating Environment (MOE) was used to simulate the aptamer and protein docking, and western blot (WB) was used to verify the binding effect and ratio. The peptide aptamer was characterized and was then reduced with tris-(2-carboxyethyl)-phosphine hydrochloride (TCEP). After electrochemical deposition of chloroauric acid on the screen-printed electrode (SPE), the aptamer was self-assembled on the electrode surface under optimal conditions. The active site of the electrode surface was blocked with 6-mercapto-1-hexanol (MCH) and BSA. The electrochemical impedance spectrum (EIS) was used to quantify HCG in the matrix. Showing a good linear relationship in the range of 5-1500 mIU mL^-1, with a detection limit of 1 mIU mL^-1, the biosensor remained stable at room temperature for 14 days. Because of its small size, stability, sensitivity and accuracy, this biosensor has great potential to become a portable diagnostic device for HCG.

Smartphone-based technology for nanomolecular detection of aflatoxin B1 by aptamer-conjugated magnetic nanoparticles

The need for a healthy market in the rapid and accurate screening of a variety of pathogenic agents and toxins in the environment and food has led to an increase in the development of new biosensors, which have ideal characteristics, such as high sensitivity and specificity with rapid detection and simple preparation of the sample. Among the food contaminants, mycotoxins have been identified as a major challenge for the food industry, and rapid and accurate detection has attracted the attention of food inspection and monitoring organisations. In this study, a nanomolecular detection method is described using aflatoxin B1 (AFB1)-specific aptamers attached to streptavidin-coated magnetic nanoparticles. A prominent feature of the AFB1-specific aptamers is a guanine-rich (G-rich) sequence with a G-quadruplex structure after capturing AFB1 molecules and mimicking peroxidase activity. The enzymatic reaction evaluated in the presence of chromogenic substrate and measurement is done by a smartphone-specific application for colorimetric measurement. The results indicated that the assay could measure AFB1 in rice, flour, seed, maize, and pistachio. In addition, the application of hybrid nanomaterial technology resulting from the binding of biotin-labelled aptamers to the surface of streptavidin-coated magnetic nanoparticles minimises preparation and treatment of samples, improves results, and consequently reduces false negative and positive responses in the detection field. This study may eventually lead to the design and development of a fast, sensitive, specific, and on-site AFB1-based nanomolecular colorimetric detection system via a smartphone-based application that can be readily accessible to all applicants, from professionals to manufacturers of foodstuffs.

Fabrication and characterization of walnut peptides-loaded proliposomes with three lyoprotectants: Environmental stabilities and antioxidant/antibacterial activities

To protect walnut peptides from harsh external environments during their storage and digestion, proliposomes loaded with walnut peptides were fabricated using sucrose, trehalose, and mannitol as carriers and lyoprotectants. The physicochemical properties, environmental stability, antioxidant/antibacterial activities, and digestion in vitro of the proliposomes were evaluated. The freshly prepared liposomes were uniform in size, but the hydrated proliposomes showed a more uneven size distribution. The lyoprotectants helped maintain favorable liposome shape during lyophilization. Alongside the lyoprotectants, the walnut peptides further stabilized the lipid bilayer. Proliposomes encapsulation didn't impact the peptides' antioxidant activity. Furthermore, walnut peptides-loaded proliposomes exhibited antibacterial activity against Escherichia coli and Staphylococcus aureus. The proliposomes were stable during gastric-phase digestion. The lyoprotectants changed the free fatty acid release behaviors of the proliposomes. These characteristics suggest potential applications for proliposomes as effective delivery systems for biopeptides in food stuffs, thereby protecting bioactivities during storage and passage through the gastrointestinal tract.

Whey allergens: Influence of nonthermal processing treatments and their detection methods

Whey and its components are recognized as value-added ingredients in infant formulas, beverages, sports nutritious foods, and other food products. Whey offers opportunities for the food industrial sector to develop functional foods with potential health benefits due to its unique physiological and functional attributes. Despite all the above importance, the consumption of whey protein (WP) can trigger hypersensitive reactions and is a constant threat for sensitive individuals. Although avoiding such food products is the most successful approach, there is still a chance of incorrect labeling and cross-contamination during food processing. As whey allergens in food products are cross-reactive, the phenomenon of homologous milk proteins of various species may escalate to a more serious problem. In this review, nonthermal processing technologies used to prevent and eliminate WP allergies are presented and discussed in detail. These processing technologies can either enhance or mitigate the impact of potential allergenicity. Therefore, the development of highly precise analytical technologies to detect and quantify the existence of whey allergens is of considerable importance. The present review is an attempt to cover all the updated approaches used for the detection of whey allergens in processed food products. Immunological and DNA-based assays are generally used for detecting allergenic proteins in processed food products. In addition, mass spectrometry is also employed as a preliminary technique for detection. We also highlighted the latest improvements in allergen detection toward biosensing strategies particularly immunosensors and aptasensors.

Bioactive components from Moringa oleifera seeds: production, functionalities and applications - a critical review

A readily distinguishable and indigenous member of the plant kingdom in the Indian subcontinent is the 'drumstick tree', i.e. Moringa oleifera Lam. In addition to India, this drought-tolerant and rapidly evolving tree is currently extensively disseminated across the globe, including subtropical and tropical areas. The plant boasts a high nutritional, nutraceutical and therapeutic profile, mainly attributing to its significant repertoire of the biologically active components in different parts: protein, flavonoids, saponins, phenolic acids, tannin, isothiocyanate, lipids, minerals, vitamins, amongst others. M. oleifera seeds have been shown to elicit a myriad of pharmacological potential and health benefits, including: antimicrobial, anticancer, antidiabetic, antioxidant, antihypertensive, anti-inflammatory and cardioprotective properties. Additionally, the seed cakes obtained from post-extraction process are utilized for: coagulation, flocculation and sedimentation purposes, benefiting effluent management and the purification of water, mainly because of their capability in eliminating microbes and organic matter. Despite the extraordinary focus on other parts of the plant, especially the foliage, the beneficial aspects of the seeds have not been sufficiently highlighted. The health benefits of bioactive components in the seeds are promising and demonstrate enough potential to facilitate the development of functional foods. In this review, we present a critical account of the types, characteristics, production and isolation of bioactive components from M. oleifera seeds. Furthermore, we appraise the: pharmacological activities, cosmetic, biodiesel, lubricative, modern farming, nutritive and wastewater treatment applications of these functional ingredients. We infer that there is a need for further human/clinical studies and evaluation, despite their health benefits. Additionally, the safety issues need to be adequately clarified and assessed, in order to establish a conventional therapeutic profile.

Establishment of a dual-aptasensor for simultaneous detection of chloramphenicol and kanamycin

Aptamers, as single-stranded DNA or RNA fragments, have been widely applied as the bio-recognition element for fabrication of flexible and reliable aptasensors to be used in food safety control, clinical therapy and diagnosis and environment monitoring fields. With increasingly fierce antibiotics resistance appearing as a worldwide problem, a highly efficient method is urgently needed to detect antibiotics residues in animal-sourced food. Herein, a simply operated aptasensor based on quantitative real-time PCR (qRT-PCR) was fabricated to realise the simultaneous detection of two antibiotics (i.e. chloramphenicol and kanamycin). The limit of detection (LOD) of 6.13 ng/mL for chloramphenicol and of 19.17 ng/mL for kanamycin of this dual-aptasensor were achieved. Actually, such LOD values were not as good as that of an aptasensor individually established for each antibiotic. The circular dichroism analysis suggested that in the dual-aptasensor, adjacent aptamers might disturb each other's binding with their respective target. Although certain detection sensitivity was lost, the dual-aptasensor could still fulfil the detection requirements, and more importantly, it would improve the detection efficiency. Finally, this dual-aptasensor was applied for detecting chloramphenicol and kanamycin in real spiked food samples, and results indicated good recovery rates. These results demonstrated this developed dual-aptasensor to be a promising highly efficient method with low cost for simultaneous detection of chloramphenicol and kanamycin residues in animal-sourced food samples.

Altered immunoemotional regulatory system in COVID-19: From the origins to opportunities

The emergence of the novel coronavirus (SARS-CoV-2) and the worldwide spread of the coronavirus disease (COVID-19) have led to social regulations that caused substantial changes in manners of daily life. The subsequent loneliness and concerns of the pandemic during social distancing, quarantine, and lockdown are psychosocial stressors that negatively affect the immune system. These effects occur through mechanisms controlled by the sympathetic nervous system (SNS) and the hypothalamic-pituitary-adrenocortical (HPA) axis that alter immune regulation, namely the conserved transcriptional response to adversity (CTRA), which promotes inflammation and diminishes antiviral responses, leading to inadequate protection against viral disease. Unhealthy eating habits, physical inactivity, sleep disturbances, and mental health consequences of COVID-19 add on to the pathological effects of loneliness, making immunity against this ferocious virus an even tougher fight. Therefore, social isolation, with its unintended consequences, has inherently paradoxical effects on immunity in relation to viral disease. Though this paradox can present a challenge, its acknowledgment can serve as an opportunity to address the associated issues and find ways to mitigate the adverse effects. In this review, we aim to explore, in detail, the pathological effects of the new social norms on immunity and present suggested methods to improve our physical, psychological, and healthcare abilities to fight viral infection in the context of the COVID-19 pandemic.

Recent advances on aptamer-based biosensors for detection of pathogenic bacteria

As a significant constituent in biosphere, bacteria have a great influence on human activity. The detection of pathogen bacteria is closely related to the human health. However, the traditional methods for detection of pathogenic bacteria are time-consuming and difficult for quantification, although they are practical and reliable. Therefore, novel strategies for rapid, sensitive, and cost-effective detection are in great demand. Aptamer is a kind of oligonucleotide that selected by repeated screening in vitro or systematic evolution of ligands by exponential enrichment (SELEX) technology. Over the past years, owing to high affinity and specificity of aptamers, a variety of aptamer-based biosensors have been designed and applied for pathogen detection. In this review, we have discussed the recent advances on the applications of aptamer-based biosensors in detection of pathogenic bacteria. In addition, we also point out some problems in current methods and look forward to the further development of aptamer-based biosensors for pathogen detection.

Antiviral Functional Foods and Exercise Lifestyle Prevention of Coronavirus

Novel coronavirus (COVID-19) is causing global mortality and lockdown burdens. A compromised immune system is a known risk factor for all viral influenza infections. Functional foods optimize the immune system capacity to prevent and control pathogenic viral infections, while physical activity augments such protective benefits. Exercise enhances innate and adaptive immune systems through acute, transient, and long-term adaptations to physical activity in a dose-response relationship. Functional foods prevention of non-communicable disease can be translated into protecting against respiratory viral infections and COVID-19. Functional foods and nutraceuticals within popular diets contain immune-boosting nutraceuticals, polyphenols, terpenoids, flavonoids, alkaloids, sterols, pigments, unsaturated fatty-acids, micronutrient vitamins and minerals, including vitamin A, B6, B12, C, D, E, and folate, and trace elements, including zinc, iron, selenium, magnesium, and copper. Foods with antiviral properties include fruits, vegetables, fermented foods and probiotics, olive oil, fish, nuts and seeds, herbs, roots, fungi, amino acids, peptides, and cyclotides. Regular moderate exercise may contribute to reduce viral risk and enhance sleep quality during quarantine, in combination with appropriate dietary habits and functional foods. Lifestyle and appropriate nutrition with functional compounds may offer further antiviral approaches for public health.

Nano-Biosensing Platforms for Detection of Cow's Milk Allergens: An Overview

Among prevalent food allergies, cow milk allergy (CMA) is most common and may persist throughout the life. The allergic individuals are exposed to a constant threat due to milk proteins' presence in uncounted food products like yogurt, cheese, and bakery items. The problem can be more severe due to cross-reactivity of the milk allergens in the food products due to homologous milk proteins of diverse species. This problem can be overcome by proper and reliable food labeling in order to ensure the life quality of allergic persons. Therefore, highly sensitive and accurate analytical techniques should be developed to detect the food allergens. Here, significant research advances in biosensors (specifically immunosensors and aptasensors) are reviewed for detection of the milk allergens. Different allergic proteins of cow milk are described here along with the analytical standard methods for their detection. Additionally, the commercial status of biosensors is also discussed in comparison to conventional techniques like enzyme-linked immunosorbent assay (ELISA). The development of novel biosensing mechanisms/kits for milk allergens detection is imperative from the perspective of enforcement of labeling regulations and directives keeping in view the sensitive individuals.

Research advances of DNA aptasensors for foodborne pathogen detection

Aptamers, referring to single-stranded DNA or RNA molecules can specifically recognize and bind to their targets. Based on their excellent specificity, sensitivity, high affinity, and simplicity of modification, aptamers offer great potential for pathogen detection and biomolecular screening. This article reviews aptamer screening technologies and aptamer application technologies, including gold-nanoparticle lateral flow assays, fluorescence assays, electrochemical assays, colorimetric assays, and surface-enhanced Raman assays, in the detection of foodborne pathogens. Although notable progress (more rapid, sensitive, and accurate) has been achieved in the field, challenges and drawbacks in their applications still remain to be overcome.