Simple and sensitive detection of acrylamide based on hemoglobin immobilization in carbon ionic liquid paste electrode

Acrylamide in food products and the role of electrochemical biosensors in its detection: a comprehensive review

In this review, the mechanisms of acrylamide formation in food, along with aspects related to its toxicity and associated consumption risks, are investigated, highlighting the potential impact on human health. European regulations regarding acrylamide content in food products are also addressed, emphasizing the importance of monitoring and detecting this substance in nutrition, by public health protection measures. The primary objective of the research is to explore and analyze innovative methods for detecting acrylamide in food, with a particular focus on electrochemical biosensors. This research direction is motivated by the need to develop rapid, sensitive, and efficient monitoring techniques for this toxic compound in food products, considering the associated consumption risks. The research has revealed several significant results. Studies have shown that electrochemical biosensors based on hemoglobin exhibited increased sensitivity and low detection limits, capable of detecting very low concentrations of acrylamide in processed foods. Additionally, it has been found that the use of functionalized nanomaterials, such as carbon nanotubes and gold nanoparticles, has led to the improvement of electrochemical biosensor performance in acrylamide detection. The integration of these technological innovations and functionalization strategies has enhanced the sensitivity, specificity, and stability of biosensors in measuring acrylamides. Thus, the results of this research offer promising perspectives for the development of precise and efficient methods for monitoring acrylamides in food, contributing to the improvement of food quality control and the protection of consumer health.

Dietary Acrylamide: A Detailed Review on Formation, Detection, Mitigation, and Its Health Impacts

In today's fast-paced world, people increasingly rely on a variety of processed foods due to their busy lifestyles. The enhanced flavors, vibrant colors, and ease of accessibility at reasonable prices have made ready-to-eat foods the easiest and simplest choice to satiate hunger, especially those that undergo thermal processing. However, these foods often contain an unsaturated amide called 'Acrylamide', known by its chemical name 2-propenamide, which is a contaminant formed when a carbohydrate- or protein-rich food product is thermally processed at more than 120 °C through methods like frying, baking, or roasting. Consuming foods with elevated levels of acrylamide can induce harmful toxicity such as neurotoxicity, hepatoxicity, cardiovascular toxicity, reproductive toxicity, and prenatal and postnatal toxicity. This review delves into the major pathways and factors influencing acrylamide formation in food, discusses its adverse effects on human health, and explores recent techniques for the detection and mitigation of acrylamide in food. This review could be of interest to a wide audience in the food industry that manufactures processed foods. A multi-faceted strategy is necessary to identify and resolve the factors responsible for the browning of food, ensure safety standards, and preserve essential food quality traits.

An Efficient Electrochemical Sensor Based on NiCo2O4 Nanoplates and Ionic Liquid for Determination of Favipiravir in the Presence of Acetaminophen

Based on the modification of carbon paste electrode with NiCo2O4 nanoplates and 1-hexyl-3-methylimidazolium tetrafluoroborate, a new electrochemical sensing platform for the sensing of favipiravir (a drug with potential therapeutic efficacy in treating COVID-19 patients) in the presence of acetaminophen was prepared. For determining the electrochemical behavior of favipiravir, cyclic voltammetry, differential pulse voltammetry, and chronoamperometry have been utilized. When compared to the unmodified carbon paste electrode, the results of the cyclic voltammetry showed that the proposed NiCo2O4 nanoplates/1-hexyl-3-methylimidazolium tetrafluoroborate/carbon paste electrode had excellent catalytic activity for the oxidation of the favipiravir in phosphate buffer solution (pH = 7.0). This was due to the synergistic influence of 1-hexyl-3-methylimidazolium tetrafluoroborate (ionic liquid) and NiCo2O4 nanoplates. In the optimized conditions of favipiravir measurement, NiCo2O4 nanoplates/1-hexyl-3-methylimidazolium tetrafluoroborate/carbon paste electrode had several benefits, such as a wide dynamic linear between 0.004 and 115.0 µM, a high sensitivity of 0.1672 µA/µM, and a small limit of detection of 1.0 nM. Furthermore, the NiCo2O4 nanoplates/1-hexyl-3-methylimidazolium tetrafluoroborate/carbon paste electrode sensor presented a good capability to investigate the favipiravir and acetaminophen levels in real samples with satisfactory recoveries.

A dual-recognition-controlled electrochemical biosensor for selective and ultrasensitive detection of acrylamide in heat-treated carbohydrate-rich food

A synergistic hybrid was fabricated for the electrochemical aptasensing of acrylamide (AAM) via molecularly imprinted technology. The aptasensor depends on the modification of glassy carbon electrode with AuNPs and reduced graphene oxide (rGO)/multiwalled carbon nanotubes (MWCNTs) {Au@rGO-MWCNTs/GCE}. The aptamer (Apt-SH) and AAM (template) were incubated with the electrode. After that, the monomer was electro-polymerized to fabricate molecular imprinted polymeric film (MIP) over the surface of Apt-SH/Au@rGO/MWCNTs/GCE. The modified electrodes were characterized using different morphological and electrochemical techniques. Under optimum conditions, the aptasensor exhibited a linear relationship between AAM concentration and anodic peak current difference (ΔIpa) in the range of 1-600 nM with a limit of quantitation (LOQ, S/N = 10) and a limit of detection (LOD, S/N = 3) of 0.346 and 0.104 nM, respectively. The aptasensor was successfully applied for the determination of AAM in potato fries samples with recoveries % in the range of 98.7-103.4 % and RSDs did not exceed 3.2 %. The advantages of MIP/Apt-SH/Au@rGO/MWCNTs/GCE are low detection limit, high selectivity, and satisfactory stability towards AAM detection.

Ionic Liquid-Based Polymer Nanocomposites for Sensors, Energy, Biomedicine, and Environmental Applications: Roadmap to the Future

Current interest toward ionic liquids (ILs) stems from some of their novel characteristics, like low vapor pressure, thermal stability, and nonflammability, integrated through high ionic conductivity and broad range of electrochemical strength. Nowadays, ionic liquids represent a new category of chemical-based compounds for developing superior and multifunctional substances with potential in several fields. ILs can be used in solvents such as salt electrolyte and additional materials. By adding functional physiochemical characteristics, a variety of IL-based electrolytes can also be used for energy storage purposes. It is hoped that the present review will supply guidance for future research focused on IL-based polymer nanocomposites electrolytes for sensors, high performance, biomedicine, and environmental applications. Additionally, a comprehensive overview about the polymer-based composites' ILs components, including a classification of the types of polymer matrix available is provided in this review. More focus is placed upon ILs-based polymeric nanocomposites used in multiple applications such as electrochemical biosensors, energy-related materials, biomedicine, actuators, environmental, and the aviation and aerospace industries. At last, existing challenges and prospects in this field are discussed and concluding remarks are provided.

Ratiometric Fluorescent Metal-Organic Framework Biosensor for Ultrasensitive Detection of Acrylamide

Acrylamide is a neurotoxin and carcinogen that forms during the thermal processing of food, inflicting irreversible harm to human health. Herein, a ratiometric fluorescence biosensor based on a 6-carboxyfluorescein-labeled aptamer (FAM-ssDNA) and porphyrin metal-organic framework (PCN-224) was developed. PCN-224 exhibits strong adsorption capacity for FAM-ssDNA and also quenches the fluorescence of FAM-ssDNA via fluorescence resonance energy transfer and photoinduced electron transfer. FAM-ssDNA hybridizes with complementary DNA to form double-stranded DNA (FAM-dsDNA), which is liberated from the PCN-224 surface, resulting in fluorescence recovery. However, the intrinsic fluorescence of the ligand remains unchanged. Acrylamide can create an adduct with FAM-ssDNA and inhibit the hybridization of FAM-dsDNA, thus realizing ratiometric sensing of acrylamide. The proposed biosensor displays excellent detection performance from 10 nM∼0.5 mM with a limit of detection of 1.9 nM. In conclusion, a fabricated biosensor was successfully applied to detect acrylamide in thermally processed food, and the results were consistent with those of high-performance liquid chromatography.

A fluorescence biosensor based on double-stranded DNA and a cationic conjugated polymer coupled with exonuclease III for acrylamide detection

As a toxic substance on human health produced in food thermal treatment, simple analytical approaches are highly desired for the detection of acrylamide (ACR) in foods. With the aid of exonuclease III (Exo III), a simple fluorescence sensor was proposed based on carboxyfluorescein-labeled double-stranded DNA (FAM-dsDNA) and a cationic conjugated polymer (PFP). Fluorescence resonance energy transfer (FRET) efficiency between FAM and PFP was changed with and without ACR. When ACR was present, ACR and single-stranded DNA (P1, ssDNA) formed an adduct, allowing free FAM-labeled complementarity strand DNA (P2, FAM-csDNA) to appear in the solution and avoiding the digestion of P2 by Exo III. After the addition of PFP, the interaction of PFP and FAM induced strong FRET. Under optimized conditions, ACR was detected with a limit of detection (LOD) of 0.16 μM. According to this biosensor, a LOD of 1.3 μM in water extract samples was observed with a good recovery rate (95-110 %).

Potent Acrylamide Determination in Food Products Using Ion-Selective Electrode Technique

A potent selective acrylamide liquid sensor based on the reaction of acrylamide with 2-(5-Bromo-2-pyridylazo)-5-[N-n-Propyl-N-(3-Sulfopropyl) amino] aniline reagent is successfully designed. The characteristics slope (52.33 mV/decade), linearity usable range from 1.0 × 10⁻⁷–1.0 × 10⁻¹ molar, limit of detection (1.6 × 10⁻⁸) molar, selectivity attitude to several inorganic cations, amino acids and sugars, time of response (8 s), lifetime (four months), pH effect on the electrode potential and the basic validation parameters were studied. The desirable pH applicable range was 3.0–6.5, and the restraint of the developed sensor is independent on this working pH range. The deployed electrode was effectively applied for rapid inexpensive analysis of acrylamide cations in food products with comparison to high-performance liquid chromatographic method and the results were agreeable with each other. The obtained data by the suggested electrode were treated statistically and compared with the various recently published acrylamide sensors.

Nanomaterials Enabled and Bio/Chemical Analytical Sensors for Acrylamide Detection in Thermally Processed Foods: Advances and Outlook

Acrylamide, a food processing contaminant with demonstrated genotoxicity, carcinogenicity, and reproductive toxicity, is largely present in numerous prominent and commonly consumed food products that are produced by thermal processing methods. Food regulatory bodies such as the U.S. Food and Drug Administration (U.S. FDA) and European Union Commission regulations have disseminated various acrylamide mitigation strategies in food processing practices. Hence, in the wake of such food and public health safety efforts, there is a rising demand for economic, rapid, and portable detection and quantification methods for these contaminants. Since conventional quantification techniques like liquid chromatography-mass spectrometry (LC-MS) and gas chromatography-mass spectrometry (GC-MS) methods are expensive and have many drawbacks, sensing platforms with various transduction systems have become an efficient alternative tool for quantifying various target molecules in a wide variety of food samples. Therefore, this present review discusses in detail the state of robust, nanomaterials-based and other bio/chemical sensor fabrication techniques, the sensing mechanism, and the selective qualitative and quantitative measurement of acrylamide in various food materials. The discussed sensors use analytical measurements ranging from diverse and disparate optical, electrochemical, as well as piezoelectric methods. Further, discussions about challenges and also the potential development of the lab-on-chip applications for acrylamide detection and quantification are entailed at the end of this review.

Poly(methylene blue)-Based Electrochemical Platform for Label-Free Sensing of Acrylamide

The present work reports the electrochemical sensing of acrylamide (AM) using a poly(methylene blue)-modified glassy carbon electrode (PMB/GCE) where PMB functions as an electrochemical reporter. PMB was prepared by electrochemical polymerization of methylene blue. Electrochemical sensing of AM was facilitated by the interaction between AM and PMB. Further the interaction between AM and PMB was investigated using ultraviolet-visible (UV-vis) spectroscopy and Raman analysis. The surface morphology was confirmed by atomic force microscopy (AFM) and field emission scanning electron microscopy (FESEM) analyses. PMB/GCE was further characterized by X-ray photoelectron spectroscopy (XPS), and the electrochemical performance was assessed using cyclic voltammetry and differential pulse voltammetry. Cyclic voltammetry analysis showed a decrease in current at the redox center of PMB upon addition of AM. The association constant and binding number of AM with PMB/GCE were calculated using differential pulse voltammetry and found to be 8.9 × 10⁶ M^-1 and 0.64 (∼1), respectively. The results indicated a strong interaction of AM on the PMB/GCE surface. Further, chronocoulometry analysis of PMB/GCE in the presence of AM showed a decrease in charge due to the interaction of AM with PMB. Under optimized conditions, PMB/GCE exhibited a decrease in current proportional to the concentration of AM in the range of 0.025-16 μM with sensitivity and detection limit 0.252 μA nM^-1 and 0.13 nM, respectively. Real sample analysis was carried out by the standard addition method using the solution extracted from potato chips.

Molecularly imprinted photoelectrochemical sensing based on ZnO/polypyrrole nanocomposites for acrylamide detection

A highly sensitive quenching molecular imprinting (MIP) photoelectrochemical (PEC) sensor was proposed to detect acrylamide (AM) by using the photoactive composite of ZnO and polypyrrole (PPy) as the PEC signal probe. ZnO, with high electron mobility, excellent chemical and thermal stability as well as good biocompatibility, was selected as the photoelectrically active material. A polypyrrole film was formed on the nanodisk ZnO by electrochemical polymerization, and the recognition site of AM was left on the surface of the PPy film by elution, enabling the specific detection of AM. The transfer of electrons will be hindered when AM is adsorbed on the ZnO/PPy nanocomposites surface, which results in the decrease of photocurrent signal. The proposed molecularly imprinted PEC sensor exhibits significant detection performance of AM in the range of 10-1 M-2.5 × 10-9 M with a LOD of 2.147 × 10-9 M (S/N = 3). The use of photoelectrochemical technology combined with molecular imprinting technology enables the PEC sensor to have excellent selectivity, superior repeatability, preferable stability, low cost, and easy construction, providing a new method for the detection of AM. The high recovery rate in the detection of real samples of potato chips and biscuits indicates that the proposed PEC sensor has potential in monitoring the emerging food safety risks.

Electrochemical (bio) sensors go green

Electrochemical (bio) sensors are now widely acknowledged as a sensitive detection tool for disease diagnosis as well as the detection of numerous species of pharmaceutical, clinical, industrial, food, and environmental origin. The term 'green' demonstrates the development of electrochemical (bio) sensing platforms utilizing biodegradable and sustainable materials. Development of green sensing platforms is one of the most active areas of research minimizing the use of toxic/hazardous reagents and solvent systems, thereby further reducing the production of chemical wastes in sensor fabrication. The present review includes green electrochemical (bio) sensors which are based on firstly, green sensors comprising natural and non-hazardous materials (e.g., paper/clay/zeolites/biowastes), secondly sensors based on nanomaterials synthesized by green methods and lastly sensors constituting green solvents (e.g., ionic liquids/deep eutectic solvents). Electrochemical performances of such green sensors and their benefits such as biodegradability, non-toxicity, sustainability, low-cost, sensitive surfaces, etc. Have been discussed for quantification of various target analytes. Associated challenges, possible solutions, and opportunities towards fabricating green electrochemical sensors and biosensors have been provided in the conclusion section.