Polymers In Biosensors Research Articles

Functionalized polymeric biosensors via electrospinning assisted by controlled radical polymerization

Functionalized polymeric biosensors via electrospinning assisted by controlled radical polymerization

Targeted microorganism detection with molecularly imprinted polymer biosensors

In this article, a molecularly imprinted polymer (MIP)-based electrochemical biosensor was developed for the detection of Enterococcus faecium, demonstrating exceptional selectivity and sensitivity in real urine samples. Our approach involved fabricating electrodes coated with bacteria-imprinted polypyrrole through electropolymerization. The surface characteristics of the molecularly imprinted polymer (MIP) and non-imprinted polymer (NIP) coated electrodes were thoroughly characterized using cyclic voltammetry and electrochemical impedance spectroscopy. Remarkably, the MIP-coated electrodes exhibited superior conductivity, highlighting their efficacy in capturing Enterococcus faecium. By subjecting the MIP-based biosensor to Enterococcus faecium incubation, we successfully monitored impedance changes, enabling the detection of minute quantities of the bacteria with a limit of detection of 9 CFU/mL. The technology could successfully distinguish Enterococcus faecium from Enterococcus faecalis, a related bacteria species within the same genus, marking a significant advancement in clinical differentiation. Additionally, the biosensor selectively captured Enterococcus faecium and discriminated it from other common bacteria, including Proteus mirabilis, Escherichia coli, Staphylococcus aureus, and Pseudomonas aeruginosa. This research underscores the utility of MIP-based electrochemical biosensors for the rapid and selective detection of Enterococcus faecium in clinical settings, with implications for targeted antibiotic therapy and infection control.

Molecularly Imprinted Polymer Biosensor Based on Nitrogen-Doped Electrochemically Exfoliated Graphene/Ti3 CNTX MXene Nanocomposite for Metabolites Detection.

Rapid and accurate quantification of metabolites in different bodily fluids is crucial for a precise health evaluation. However, conventional metabolite sensing methods, confined to centralized laboratory settings, suffer from time-consuming processes, complex procedures, and costly instrumentation. Introducing the MXene/nitrogen-doped electrochemically exfoliated graphene (MXene@N-EEG) nanocomposite as a novel biosensing platform in this work addresses the challenges associated with conventional methods, leveraging the concept of molecularly imprinted polymers (MIP) enables the highly sensitive, specific, and reliable detection of metabolites. To validate our biosensing technology, we utilize agmatine as a significant biologically active metabolite. The MIP biosensor incorporates electrodeposited Prussian blue nanoparticles as a redox probe, facilitating the direct electrical signaling of agmatine binding in the polymeric matrix. The MXene@N-EEG nanocomposite, with excellent metal conductivity and a large electroactive specific surface area, effectively stabilizes the electrodeposited Prussian blue nanoparticles. Furthermore, increasing the content of agmatine-imprinted cavities on the electrode enhances the sensitivity of the MIP biosensor. Evaluation of the designed MIP biosensor in buffer solution and plasma samples reveals a wide linear concentration range of 1.0 nM-100.0 μM (R2 = 0.9934) and a detection limit of 0.1 nM. Notably, the developed microfluidic biosensor offers low cost, rapid response time to the target molecule (10 min of sample incubation), good recovery results for detecting agmatine in plasma samples, and acceptable autonomous performance for on-chip detection. Moreover, its high reliability and sensitivity position this MIP-based biosensor as a promising candidate for miniaturized microfluidic devices with the potential for scalable production for point-of-care applications.

Biomedical applications of polymers in biosensors, cancer vaccines and drug delivery systems

Biomedical applications of polymers in biosensors, cancer vaccines and drug delivery systems

A graphene nanoplatelet-polydopamine molecularly imprinted biosensor for Ultratrace creatinine detection

Accurate and reliable analysis of creatinine is clinically important for the early detection and monitoring of patients with kidney disease. We report a novel graphene nanoplatelet (GNP)/polydopamine (PDA)-molecularly imprinted polymer (MIP) biosensor for the ultra-trace detection of creatinine in a range of body fluids. Dopamine hydrochloride (DA) monomers were polymerized using a simple one-pot method to form a thin PDA-MIP layer on the surface of GNP with high density of creatinine recognition sites. This novel surface-MIP strategy resulted in a record low limit-of-detection (LOD) of 2 × 10−2 pg/ml with a wide dynamic detection range between 1 × 10−1-1 × 109 pg/ml. The practical application of this GNP/PDA-MIP biosensor has been tested by measuring creatinine in human serum, urine, and peritoneal dialysis (PD) fluids. The average recovery rate was 93.7–109.2% with relative standard deviation (RSD) below 4.1% compared to measurements made using standard clinical laboratory methods. Our GNP/PDA-MIP biosensor holds high promise for further development as a rapid, accurate, point-of-care diagnostic platform for detecting and monitoring patients with kidney disease.

Bio-enhanced polyrhodanine/graphene Oxide/Fe3O4 nanocomposite with kombucha solvent supernatant as ultra-sensitive biosensor for detection of doxorubicin hydrochloride in biological fluids

Cardiotoxicity and other side effects of current antineoplastic agents with narrow therapeutic windows, such as doxorubicin hydrochloride (DOX), have increased the need for advanced real-time monitoring approaches to control their dosage and minimize common side effects. In this study, we reinforced the biocompatible and electrosensitive polymeric structure of polyrhodanine with iron(II,III) oxide (Fe3O4) and coated graphene oxide (GO) with Fe3O4 (GO-Fe3O4) nanoparticles. The resulting hybrid polymeric platform was bio-enhanced by extraction of kombucha solvent supernatant and used as a highly sensitive biosensor with enhanced electroactive CN+ functional groups for real-time detection of DOX in the human blood plasma sample. The developed platform was well characterized by performing different analyses, and its applicability was evaluated using an electrochemical approach. The results showed the superior sensitivity (167.62 μA μM−1 cm−2), low detection limit (DL, 0.008 μM), and quantification limit (QL, 0.056 μM) of the proposed biosensor. The biosensor detected DOX in the biological fluid with optimal accuracy (>99%), highlighting the ideal performance of the fabricated polymeric biosensor.

Bioinorganic Synthesis of Sodium Polytungstate/Polyoxometalate in Microbial Kombucha Media for Precise Detection of Doxorubicin.

In this study, we have developed a new platform of polyoxometalate as a biocompatible and electrosensitive polymeric biosensor for the accurate detection of doxorubicin. For this purpose, we used a green synthesis approach using tartaric acid, glutamic acid, and kombucha solvent. Thanks to its bioinorganic components, the biogenic approach can chemically modify and improve the performance of the biosensor, which was experimentally confirmed. Our results showed excellent sensitivity (175.72 μA·μM−1·cm−2), low detection limit (DL, 8.12 nM), and low quantification limit (QL, 0.056 μM) when the newly developed biosensor was used. The results also show that the biosynthesized biosensor has improved performance in detecting DOX in the biological fluid with an accuracy of more than 99% depending on the components used, which underlines the high efficiency of the biosensor produced. Considering the body's physiological condition, the biosensor fabricated as a biocompatible component can show high efficiency. Therefore, its applicability for clinical use still needs to be studied in detail.

Isolating Specific vs. Non-Specific Binding Responses in Conducting Polymer Biosensors for Bio-Fingerprinting.

A longstanding challenge for accurate sensing of biomolecules such as proteins concerns specifically detecting a target analyte in a complex sample (e.g., food) without suffering from nonspecific binding or interactions from the target itself or other analytes present in the sample. Every sensor suffers from this fundamental drawback, which limits its sensitivity, specificity, and longevity. Existing efforts to improve signal-to-noise ratio involve introducing additional steps to reduce nonspecific binding, which increases the cost of the sensor. Conducting polymer-based chemiresistive biosensors can be mechanically flexible, are inexpensive, label-free, and capable of detecting specific biomolecules in complex samples without purification steps, making them very versatile. In this paper, a poly (3,4-ethylenedioxyphene) (PEDOT) and poly (3-thiopheneethanol) (3TE) interpenetrating network on polypropylene–cellulose fabric is used as a platform for a chemiresistive biosensor, and the specific and nonspecific binding events are studied using the Biotin/Avidin and Gliadin/G12-specific complementary binding pairs. We observed that specific binding between these pairs results in a negative ΔR with the addition of the analyte and this response increases with increasing analyte concentration. Nonspecific binding was found to have the opposite response, a positive ΔR upon the addition of analyte was seen in nonspecific binding cases. We further demonstrate the ability of the sensor to detect a targeted protein in a dual-protein analyte solution. The machine-learning classifier, random forest, predicted the presence of Biotin with 75% accuracy in dual-analyte solutions. This capability of distinguishing between specific and nonspecific binding can be a step towards solving the problem of false positives or false negatives to which all biosensors are susceptible.

Veterinary Drug Residues in Animal-Derived Foods: Sample Preparation and Analytical Methods.

Veterinary drugs are used to treat livestock and aquatic diseases and thus are introduced into animal-derived foods, endangering consumer health and safety. Antibiotic resistance is rapidly becoming a major worldwide problem, and there has been a steady increase in the number of pathogens that show multi-drug resistance. Illegal and excessive use of veterinary drugs in animals and aquaculture has serious adverse effects on humans and on all other environmental organisms. It is necessary to develop simple extraction methods and fast analytical methods to effectively detect veterinary drug residues in animal-derived foods. This review summarizes the application of various sample extraction techniques and detection and quantification methods for veterinary drug residues reported in the last decade (2010-2020). This review compares the advantages and disadvantages of various extraction techniques and detection methods and describes advanced methods, such as those that use electrochemical biosensors, piezoelectric biosensors, optical biosensors, and molecularly imprinted polymer biosensors. Finally, the future prospects and trends related to extraction methods, detection methods and advanced methods for the analysis of veterinary drug residues in animal-derived foods are summarized.

Transport and kinetics in electrocatalytic thin film conducting polymer biosensors: bounded diffusion with Michaelis-Menten kinetics incorporating general inhibition effects

Transport and kinetics in electrocatalytic thin film conducting polymer biosensors: bounded diffusion with Michaelis-Menten kinetics incorporating general inhibition effects

The Use of Aptamers and Molecularly Imprinted Polymers in Biosensors for Environmental Monitoring: A Tale of Two Receptors

Effective molecular recognition remains a major challenge in the development of robust receptors for biosensing applications. Over the last three decades, aptamers and molecularly imprinted polymers (MIPs) have emerged as the receptors of choice for use in biosensors as viable alternatives to natural antibodies, due to their superior stability, comparable binding performance, and lower costs. Although both of these technologies have been developed in parallel, they both suffer from their own unique problems. In this review, we will compare and contrast both types of receptor, with a focus on the area of environmental monitoring. Firstly, we will discuss the strategies and challenges involved in their development. We will also discuss the challenges that are involved in interfacing them with the biosensors. We will then compare and contrast their performance with a focus on their use in the detection of environmental contaminants, namely, antibiotics, pesticides, heavy metals, and pathogens detection. Finally, we will discuss the future direction of these two technologies.

Progress on Structured Biosensors for Monitoring Aflatoxin B1 From Biofilms: A Review.

Aspergillus exists commonly in many crops and any process of crop growth, harvest, storage, and processing can be polluted by this fungus. Once it forms a biofilm, Aspergillus can produce many toxins, such as aflatoxin B1 (AFB1), ochratoxin, zearalenone, fumonisin, and patulin. Among these toxins, AFB1 possesses the highest toxicity and is labeled as a group I carcinogen in humans and animals. Consequently, the proper control of AFB1 produced from biofilms in food and feed has long been recognized. Moreover, many biosensors have been applied to monitor AFB1 in biofilms in food. Additionally, in recent years, novel molecular recognition elements and transducer elements have been introduced for the detection of AFB1. This review presents an outline of recent progress made in the development of biosensors capable of determining AFB1 in biofilms, such as aptasensors, immunosensors, and molecularly imprinted polymer (MIP) biosensors. In addition, the current feasibility, shortcomings, and future challenges of AFB1 determination and analysis are addressed.

Bioinformatics Analysis of Linear B-cell Viscumin Toxin Epitope With Potential Use in Molecularly Imprinted Polymer Biosensors

Background: There are many diseases around the world that threaten human health and its related hygienic issues. Cancer is among the conditions mentioned above that cause many problems for health sectors worldwide.Methods: The present research analyzed the linear B-cell epitope of viscumin from European mistletoe using bioinformatics tools. We also provided references for the fast detection of biological agents. Several important tools, such as Protparam, NCBI, PDB, T-coffee, BCpred, Bptope, Ellipro, and Cn3D were used to predict the viscumin linear epitope and its physical and chemical properties.Results: The 9-mer epitope found as QQTTGEEYF embedded in the A-chain of protein by the least sequence homology with other homologous rivals. Its molecular weight, theoretical isoelectric point, and the total number of negatively charged residues were 1102.1, 3.79, and 2, respectively.Conclusion: Using different databases and establishing the accuracy level of ˃50% for linear B-cell epitope prediction, the selected epitope passed the related criteria and was introduced as a new linear epitope as a potential biological element in biosensors for cancer (viscumin) fast therapeutic detection.

Properties of Biopolymers Detection with Piezoelectric Polymer Biosensor in Relaxation Behavior Process

Properties of Biopolymers Detection with Piezoelectric Polymer Biosensor in Relaxation Behavior Process

Molecular recognition with soft biomaterials.

Biomacromolecules and engineered materials can achieve molecular recognition if they engage their ligand with properly oriented and chemically complementary moieties. Recently, there has been significant interest in fabricating recognitive soft materials, which possess specific affinity for biological analytes. We present a summary and evaluation of current recognitive materials for biosensing, drug delivery, and regenerative medicine applications. We highlight the impact of material composition on the extent and specificity of ligand adsorption, citing new theoretical and empirical evidence. We conclude with a guide for synthesizing and characterizing novel recognitive materials, as well as recommendations for ligand selection and experimental design.

Glucose sensing and hybrid instrumentation based on printed organic electrochemical transistors

This report presents the design and fabrication of a fully open-air printed organic polymer biosensor for detecting hypo/hyperglycaemia among humans with a fully integrated inorganic measurement and notification circuitry fabricated on a single flexible plastic substrate. The sensor is based on the electrochemical doping and de-doping of the degenerately doped organic semiconductor Poly(3,4-ethylenedioxythiophene) poly(styrene sulphonate) (PEDOT:PSS). The printed sensor reported herein, demonstrated sensitivity between 0.001 and 10 mM glucose concentrations utilizing a PEDOT: PSS gate, hence allowing for saliva-based, non-invasive glucose measurements. Transimpedance amplification and data processing circuitry for a prototype measurement and notification system was developed using three inexpensive chips: On Semiconductor’s CAT102 precision regulator, Texas Instruments’ LM358DR op-amp and Microchip’s-ATMEGA328PB-AUR, all integrated on the same polyethylene terephthalate substrate using screen-printed Ag interconnects and vertically conducting anisotropic glue to demonstrate the system’s practicability as a cheap, self-reliant, battery powered bio-sensing module. To demonstrate the efficacy of the system ‘as is’, no redox mediators to amplify the biosensor response were employed.

Electrodeposition of Zwitterionic PEDOT Films for Conducting and Antifouling Surfaces.

Conferring antifouling properties can extend the use of conducting polymers in biosensors and bioelectronics under complex biological conditions. On the basis of the antifouling properties of a series of zwitterionic polymers, we synthesized new thiophene-based compounds bearing a phosphorylcholine, carboxybetaine, or sulfobetaine pendant group. The monomers were synthesized by a facile reaction of thiol-functionalized 3,4-ethylenedioxythiophene with zwitterionic methacrylates. Electrochemical copolymerization was performed to deposit zwitterionic poly(3,4-ethylenedioxythiophene) (PEDOT) films with tunable conducting and antifouling properties on a conducting substrate. Electrochemical impedance spectroscopy showed that the conductivity and capacitance decreased with increasing zwitterionic content in the films. Protein adsorption and cell adhesion studies showed the effects of the type and content of zwitterions on the antifouling characteristics. Optimization of the electrodeposition conditions enabled development of both conducting and antifouling polymer films. These antifouling conjugated functional polymers have promising applications in biological environments.

Abstract 3869: A nanofiber-based biosensor for ultrasensitive detection of serum CRP in melanoma

Abstract Purpose: Early detection of melanoma is important to improve survival; however, the technology for accurate early diagnosis is still challenging. This study is to develop a novel polymeric biosensor that could provide superior sensitivity in the detection of potential early biomarkers (e.g., CRP) of melanoma. Experimental Procedure: Our strategy is to construct a highly specific molecular recognition core and a highly responsive transducer made of conductive polypyrrole (PPy) nanofibers. Briefly, a polymeric matrix was produced by polymerization of acrylamide (AM), methylenebisacrylamide (MBAA), N-Isopropylacrylamide (NIPAAm) and CRP/CRP-aptamer complex first. Next, taking advantage of the porous structure of this NIPAAm-AM-CRP-aptamer/CRP polymeric matrix, we synthesized a polypyrrole-based conductive nanofiber structure using copper phthalocyanine-3,4',4'',4‴-tetrasulfonic acid tetrasodium salt (CuPT) as a dopant counterion in situ to achieve uniformly dispersed nanofibers within the polymeric network of NIPAAm-AM-CRP-aptamer/CRP. After removing CRP recombinant protein, we were able to obtain a robust CuPT-PPy/NIPAAm-AM polymeric sensor for the detection of CRP with high sensitivity and selectivity. Two-step signal amplification cascades were involved in this CRP-specific polymeric sensor: 1) CRP binding-induced polymeric network shrinkage; 2) shrinkage-triggered conductance change of the polymeric network. Therefore, serum CRP levels could be quantitatively analyzed through monitoring the conductance change caused by polymeric network shrinkage upon aptamer-CRP binding. Results: The limit of detection (LOD) of the polymeric sensor for detection of human recombinant CRP could reach 10^−19 M. The Fourier transform infrared (FT-IR) spectra confirmed the chemical structure of the polymeric network, and the morphology was observed using scanning electron microscopy (SEM) and atomic force microscopy (AFM). The results of FT-IR reveal that CuPT-PPy nanofiber was successfully synthesized in situ. The nanostructure of the nanofibers was clearly observed using SEM and AFM, indicating that the diameter of nanofiber is about 20 nm. This CRP-specific biosensor and a commercial CRP ELISA kit were used to perform side-by-side measurement of serum CRP in melanoma patients. Conclusion: Our results indicated that this CRP-specific conductive polymeric senor is highly sensitive and selective in accurately discriminating melanoma patients from healthy controls. Such a flexible conductive polymeric biosensor may hold great promise as a point-of-care device in the diagnostics of melanoma or other cancers. Citation Format: Zuan-Tao Lin, Yaxi Li, Tianfu Wu. A nanofiber-based biosensor for ultrasensitive detection of serum CRP in melanoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 3869.

A Conductive Nanowire‐Mesh Biosensor for Ultrasensitive Detection of Serum C‐Reactive Protein in Melanoma

AbstractDetection of extracutaneous melanoma is still challenging and is of importance in improving survival rate. In this report, an ultrasensitive biosensor is constructed where a C‐reactive protein (CRP) aptamers based molecular recognition core and a conductive polypyrrole (PPy) nanowire mesh based signal amplifier are developed. The conductive PPy nanowire (less than 10 nm in diameter) mesh architecture is uniformly dispersed within polymeric matrix via template‐free in situ synthesis. Serum CRP levels are quantitatively analyzed through monitoring the conductance change caused by polymeric network shrinkage upon the aptamer‐CRP binding. The limit of detection (LOD) of the polymeric sensor for human CRP sample can reach 7.85 × 10−19m. This CRP‐specific biosensor and a commercial CRP enzyme‐linked immunosorbent assay (ELISA) kit are used to perform side‐by‐side measurement of serum CRP in melanoma patients. The results indicate that this conductive polymeric senor is highly sensitive and selective in accurately discriminating melanoma patients from healthy controls using serum CRP as a biomarker, which is further validated by a commercial human CRP ELISA kit. Collectively, this novel ultrasensitive nanowire‐based polymeric biosensor may hold promise in biomarker detection and diagnosis of cancer.

Dependence of yield of nuclear track-biosensors on track radius and analyte concentration

Abstract In swift heavy ion track-based polymeric biosensor foils with incorporated enzymes one exploits the correlation between the analyte concentration and the sensor current, via the enrichment of charged enzymatic reaction products in the track’s confinement. Here we study the influence of the etched track radius on the biosensor’s efficiency. These sensors are analyte-specific only if both the track radii and the analyte concentration exceed certain threshold values of ∼15 nm and ∼10−6 M (for glucose sensing), respectively. Below these limits the sensor signal stems un-specifically from any charge carrier. In its proper working regime, the inner track walls are smoothly covered by enzymes and the efficiency is practically radius independent. Theory shows that the measured current should be slightly sub-proportional to the analyte concentration; the measurements roughly reconfirm this. Narrower tracks (∼5–15 nm radius) with reduced enzyme coverage lead to decreasing efficiency. Tiny signals visible when the tracks are etched to effective radii between 0 and ∼5 nm are tentatively ascribed to enzymes bonded to surface-near nano-cracks in the polymer foil, resulting from its degradation due to aging, rather than to the tracks. Precondition for this study was the accurate determination of the etched track radii, which is possible only by a nanofluidic approach. This holds to some extent even for enzyme-covered tracks, though in this case most of the wall charges are compensated by enzyme bonding.