Nano interfaced biosensor for detection of choline in triple negative breast cancer cells

Nanowire-like phosphorus modulated carbon-based iron nanozyme with oxidase-like activity for sensitive detection of choline and dye degradation

Choline is mainly supplemented through food intake, lack of choline would result in diseases like liver cirrhosis, hardening of the arteries, or neurodegenerative disorders. The accurate detection of choline is important for human health. Herein, a novel nanowire-like phosphorus/nitrogen co-doped carbon-based iron nanozyme (Fe-NPC) with outstanding oxidase-like activity was synthesized, and the influence of phosphorus doping on oxidase-like activity was explored. Proper phosphorus doping was found to enhance the oxidase-like activity of Fe-NPC by increasing surface defects, promoting iron loading, and modulating chemical environment of central site. The oxidase-like activity of Fe-NPC was successfully applied to colorimetric-fluorescent dual mode detection of choline, and good linear relationship in the ranges of 3-200 μM were achieved with LODs of 1.95 and 1.50 μM, respectively. The fluorescent detection was constructed based on the fluorescence quenching of silicon quantum dots (Si QDs) by quinone-imine. The quenching mechanism was attributed to FRET due to the large spectra overlap, reduced fluorescence lifetime and proper donor-acceptor distance. The successful application to the detection of choline in milk proved the practicability of the proposed sensing method. The oxidase-like properties of Fe-NPC was further used in the degradation of cationic dye methyl blue, high degradation efficiency of 74 % was achieved within 5 min under optimal conditions, proving the enormous potential of Fe-NPC for application in environment protection.

Electrochemical Immunoassay for Capturing Capsular Polysaccharide of Burkholderia pseudomallei: Early Onsite Detection of Melioidosis

This study presented the detection and quantification of capsular polysaccharide (CPS) as a biomarker for the diagnosis of melioidosis. After successfully screening four monoclonal antibodies (mAbs) previously determined to bind CPS molecules, the team developed a portable electrochemical immunosensor based on antibody-antigen interactions. The biosensor was able to detect CPS with a wide detection range from 0.1pg/mL to 1 μg/mL. The developed biosensor achieved high sensitivity for the detection of CPS spiked into both urine and serum. The developed assay platform was successfully programmed into a Windows app, and the sensor performance was evaluated with different spiked concentrations. The rapid electro-analytical device (READ) sensor showed great unprecedented sensitivity for the detection of CPS molecules in both serum and urine, and results were cross-validated with ELISA methods.

Nanotechnology‐based electrochemical biosensors for monitoring breast cancer biomarkers

Breast cancer is categorized as the most widespread cancer type among women globally. On-time diagnosis can decrease the mortality rate by making the right decision in the therapy procedure. These features lead to a reduction in medication time and socioeconomic burden. The current review article provides a comprehensive assessment for breast cancer diagnosis using nanomaterials and related technologies. Growing use of the nano/biotechnology domain in terms of electrochemical nanobiosensor designing was discussed in detail. In this regard, recent advances in nanomaterial applied for amplified biosensing methodologies were assessed for breast cancer diagnosis by focusing on the advantages and disadvantages of these approaches. We also monitored designing methods, advantages, and the necessity of suitable (nano) materials from a statistical standpoint. The main objective of this review is to classify the applicable biosensors based on breast cancer biomarkers. With numerous nano-sized platforms published for breast cancer diagnosis, this review tried to collect the most suitable methodologies for detecting biomarkers and certain breast cancer cell types.

Zinc Oxide Nanoparticles as Diagnostic Tool for Cancer Cells

ZnO nanoparticles have various characteristics that make them attractive to be used in many medical applications like a cancer diagnosis. It can be used as a nanoprobe for targeting different types of cancer cells in vitro as a cancer cell recognition system. The present study aims to investigate the permeability of ZnO NPs through both normal and cancerous cell lines in humans. In vitro experiments for ZnO NPs inside the environment of living cells have been described, which would contribute to the visualization of nanoparticles as cancer diagnostic and scanning techniques. MCF7, AMJ13, and RD cancer cells, and also the normal breast cell line HBL, were used in in vitro imaging experiments. The findings revealed that ZnO NPs specifically incorporated within tumor cells while accumulating less inside normal cells. Our findings show that ZnO NPs may be identified inside cancer cells after 1 h of exposure and can endure up to 3 h, providing them appropriate for tumor cell imaging. The findings showed that ZnO NPs might be employed as an alternate fluorophore for diagnostic imaging in the early identification of solid cancers. Therefore, here we studied in vitro applications of ZnO NPs and their beneficial use as a diagnostic tool for cancer cell lines rather than normal cells. Taken together, ZnO NPs can be used as good targeting NPs for the development of imaging agents for early diagnosis of cancers.

Developing Integrated Approaches for Testing and Assessment (IATAs) in order to support nanomaterial safety

Due to the unique characteristics of nanomaterials (NM) there has been an increase in their use in nanomedicines and innovative medical devices (MD). Although large numbers of NMs have now been developed, comprehensive safety investigations are still lacking. Current gaps in understanding the potential mechanisms of NM-induced toxicity can make it challenging to determine the safety testing necessary to support inclusion of NMs in MD applications. This article provides guidance for implementation of pre-clinical tailored safety assessment strategies with the aim to increase the translation of NMs from bench development to clinical use. Integrated Approaches to Testing and Assessment (IATAs) are a key tool in developing these strategies. IATAs follow an iterative approach to answer a defined question in a specific regulatory context to guide the gathering of relevant information for safety assessment, including existing experimental data, integrated with in silico model predictions where available and appropriate, and/or experimental procedures and protocols for generating new data to fill gaps. This allows NM developers to work toward current guidelines and regulations, while taking NM specific considerations into account. Here, an example IATA for NMs with potential for direct blood contact was developed for the assessment of haemocompatibility. This example IATA brings together the current guidelines for NM safety assessment within a framework that can be used to guide information and data gathering for the safety assessment of intravenously injected NMs. Additionally, the decision framework underpinning this IATA has the potential to be adapted to other testing needs and regulatory contexts.

Choline Oxidase-Integrated Copper Metal-Organic Frameworks as Cascade Nanozymes for One-Step Colorimetric Choline Detection

Choline is an important factor for regulating human health and is widely present in various foods. In this work, a sensor strategy based on a choline oxidase-integrated copper(II) metal-organic framework with peroxidase-like activity is constructed for one-step cascade detection of choline. The one-step cascade strategy can avoid intermediate product transferring in general multi-step reactions, and the multi-enzyme activities can be well exerted under one condition, thus exhibiting excellent catalytic activity and enhanced stability. In the integrated system, choline is catalyzed by ChO_x to produce betaine and H₂O₂, which eventually got converted to hydroxyl radicals by the peroxidase nanozyme, oxidized the chromogenic substrate ABTS, and produced an observable absorption peak at 420 nm. A new choline detection method was thus established and showed a satisfactory linear relationship at 6-300 μM, which has been used for the choline analysis in milk.

Recent Advances in Zinc Oxide Nanoparticles (ZnO NPs) for Cancer Diagnosis, Target Drug Delivery, and Treatment

Cancer is regarded as one of the most deadly and mirthless diseases and it develops due to the uncontrolled proliferation of cells. To date, varieties of traditional medications and chemotherapies have been utilized to fight tumors. However, their immense drawbacks, such as reduced bioavailability, insufficient supply, and significant adverse effects, make their use limited. Nanotechnology has evolved rapidly in recent years and offers a wide spectrum of applications in the healthcare sectors. Nanoscale materials offer strong potential for curing cancer as they pose low risk and fewer complications. Several metal oxide NPs are being developed to diagnose or treat malignancies, but zinc oxide nanoparticles (ZnO NPs) have remarkably demonstrated their potential in the diagnosis and treatment of various types of cancers due to their biocompatibility, biodegradability, and unique physico-chemical attributes. ZnO NPs showed cancer cell specific toxicity via generation of reactive oxygen species and destruction of mitochondrial membrane potential, which leads to the activation of caspase cascades followed by apoptosis of cancerous cells. ZnO NPs have also been used as an effective carrier for targeted and sustained delivery of various plant bioactive and chemotherapeutic anticancerous drugs into tumor cells. In this review, at first we have discussed the role of ZnO NPs in diagnosis and bio-imaging of cancer cells. Secondly, we have extensively reviewed the capability of ZnO NPs as carriers of anticancerous drugs for targeted drug delivery into tumor cells, with a special focus on surface functionalization, drug-loading mechanism, and stimuli-responsive controlled release of drugs. Finally, we have critically discussed the anticancerous activity of ZnO NPs on different types of cancers along with their mode of actions. Furthermore, this review also highlights the limitations and future prospects of ZnO NPs in cancer theranostic.

Quantitative quadrupolar NMR (qQNMR) using nitrogen-14 for the determination of choline in complex matrixes

NMR offers the unique potential to selectively excite the chosen nuclei avoiding in an extraordinary way the matrix effect. Quantitative Nitrogen-14 NMR (¹⁴N qNMR) spectroscopy has been introduced for the first time as a robust and validated method to determine choline in a variety of matrixes including quinoa grains, instant coffee and food supplements. A study about the ion pairing of choline bitartrate in aqueous solution by means of diffusion PGSE, NOESY and HOESY NMR have been also provided. Validation of the method within eight concentrations levels (from 1.58 to 79.0 mM) afforded a limit of detection of 400 μg/mL (1.58 mM), a quantification limit of 1000 μg/mL (3.95 mM), excellent linearity (R² higher than 0.999), intra-/inter-day precisions lower than 1.24% (CV), recoveries of 93.5%-102.5%, and complete absence of matrix effect. The fast and reliable quantification of choline together with the accuracy and simplicity of this new approach make it useful in the development of analytical procedures that could dramatically affect traditional analysis.

Triple Negative Breast Cancer: A Review of Present and Future Diagnostic Modalities

Triple-negative breast cancer (TNBC) is an aggressive breast type of cancer with no expression of estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor-2 (HER2). It is a highly metastasized, heterogeneous disease that accounts for 10-15% of total breast cancer cases with a poor prognosis and high relapse rate within five years after treatment compared to non-TNBC cases. The diagnostic and subtyping of TNBC tumors are essential to determine the treatment alternatives and establish personalized, targeted medications for every TNBC individual. Currently, TNBC is diagnosed via a two-step procedure of imaging and immunohistochemistry (IHC), which are operator-dependent and potentially time-consuming. Therefore, there is a crucial need for the development of rapid and advanced technologies to enhance the diagnostic efficiency of TNBC. This review discusses the overview of breast cancer with emphasis on TNBC subtypes and the current diagnostic approaches of TNBC along with its challenges. Most importantly, we have presented several promising strategies that can be utilized as future TNBC diagnostic modalities and simultaneously enhance the efficacy of TNBC diagnostic.

Development of choline biosensor using toluidine blue O as mediator

A new choline oxidase (ChO) and toluidine blue O (TBO) based amperometric choline biosensor was reported in this article. An amperometric choline biosensor with immobilization of TBO (as a mediator), ChO onto polypyrrole-polyvinylsulphonate (PPy-PVS) film was accomplished on the surface of a platinum electrode. ChO was immobilized on PPy-PVS film by cross-linking with glutaraldehyde (GA). TBO was used as the mediator. Choline is oxidized to betaine and hydrogen peroxide in an oxygenated environment by ChO. Mediator reduced by reaction with hydrogen peroxide. The amperometric response was based upon the electrocatalytic properties of TBO. Optimum pH and temperature values were 7.0 and 30 °C, respectively. There was linearity between 1.0 × 10^-8 and 2.0 × 10^-8 M (R² = 0.9805). The detection limit of the biosensor was 1.0 × 10^-9 M and response time of the biosensor was 200 s. The storage stability and reproducibility of the biosensor were also investigated. Interfering effect of several interferants such as ascorbic acid, uric acid, alanine, dopamine, paracetamol, cysteine, and glucose on the choline biosensor was examined. The developed biosensor was tested in determinations of content in a synthetic blood sample.

Detection of choline in biological fluids from patients on haemodialysis by an amperometric biosensor based on a novel anti-interference bilayer

A new and highly selective amperometric biosensor able to analyse choline in clinical samples from patients suffering from renal diseases and receiving repetitive haemodialysis treatment is described. The proposed biosensor is based on choline oxidase immobilized by co-crosslinking onto a novel anti-fouling and anti-interferent membrane. Between the several polymeric films electrosynthesized on a Pt electrode whose permselective behaviours were here investigated, those based on overoxidized polypyrrole/poly(o-aminophenol) bilayer revealed the most effective in rejecting common interferents usually present in biological fluids. The so realized biosensor showed notably analytical performances, displaying linear choline responses up to 100 μM, a sensitivity of 156 nA mM^-1 mm^-2 and a limit of detection, calculated at a signal-to-noise ratio equal to 3, of 1 μM; further, the within-a-day coefficients of variation for replicate (n = 3) were 2.7% and 1.2% at 100 μM and 10 μM choline levels, respectively. The remarkable performances and anti-interference behaviour allowed us the use of the proposed biosensor for the selective and fouling-free detection of choline in dialysate coming from patients on haemodialysis and even in their unpretreated human sera. Preliminary results gave choline levels in good agreement with the expected values.

Detection of toxic choline based on Mn2O3/NiO nanomaterials by an electrochemical method

In this study, a novel in situ choline sensor was assembled by attaching the binary Mn₂O₃/NiO nanoparticles (NPs) onto a glassy carbon electrode (GCE). Initially, Mn₂O₃/NiO NPs were synthesized via a wet-chemical process and fully characterized via XRD, XPS, FESEM, EDS, FTIR and UV-Vis methods. The analytical performances of the choline sensor were evaluated by an electrochemical method in the phosphate buffer phase. The estimated linear dynamic range (LDR) was found to be 0.1 nM to 0.1 mM. The other analytical performances of the choline sensor, such as sensitivity (16.4557 μA μM⁻¹ cm⁻²) and detection limit (5.77 ± 0.29 pM), were also calculated very carefully from the calibration plot. Overall, the choline sensor exhibited a reliable reproducibility, in situ validity, selectivity, interference effect, stability, and intra-day and inter-day performances with high accuracy in a short response time. Moreover, the probe was successfully applied to detect choline in real human, mouse and rabbit serum. This fabrication route would be a novel approach for the detection of selective biochemical sensor in the healthcare and biomedical fields.

In this study, a novel in situ choline sensor was assembled by attached the binary Mn₂O₃/NiO nanoparticles onto glassy carbon electrode, which might be a reliable way to develop of future sensor in the field of biomedical and healthcare fields.

Specific enzymatic synthesis of 2,3-diaminophenazine and copper nanoclusters used for dual-emission ratiometric and naked-eye visual fluorescence sensing of choline

This work reports a novel biosensor for dual-emission ratiometric and visual fluorescence detection of choline.

Biosensing breast cancer cells based on a three-dimensional TIO2 nanomembrane transducer

The early diagnosis of breast cancer is crucial for the successful treatment and recovery phases of the patients suffering from the disease. Although mammography is considered the gold standard for diagnosis, it fails to detect some cancers in high-density breasts. In this work, we propose for the first time a tridimensional biosensor platform, to be used on an electrochemical point-of-care device. The bioconjugated platform is constructed on a series of covalent linkages between lectin molecules and a cysteine layer immobilized over gold-coated TiO₂ butterfly-like tridimensional nanomembranes. Through the use of vegetal lectins, we managed to take advantage of the markedly atypical glycomic profile of the cancerous mammalian cell membrane and successfully made a distinction between highly invasive (T47D) and less invasive (MCF7) cancer cell lines. The selectivity of the biosensor was tested by using normal human skin-fibroblast. The proposed cytosensor demonstrated limits of detection as low as 10 cells mL^-1 for every cell line and a linear range from 10 to 1.0×10⁶ cells mL^-1. Considering that electrochemical impedance values can be correlated with the number of breast cancer cells present in the sample, we suggest that the proposed platform could be useful in facilitating the diagnosis of cancer.

Biosensors for breast cancer diagnosis: A review of bioreceptors, biotransducers and signal amplification strategies

Breast cancer is highly prevalent in females and accounts for second highest number of deaths, worldwide. Cumbersome, expensive and time consuming detection techniques presently available for detection of breast cancer potentiates the need for development of novel, specific and ultrasensitive devices. Biosensors are the promising and selective detection devices which hold immense potential as point of care (POC) tools. Present review comprehensively scrutinizes various breast cancer biosensors developed so far and their technical evaluation with respect to efficiency and potency of selected bioreceptors and biotransducers. Use of glycoproteins, DNA biomarkers, micro-RNA, circulatory tumor cells (CTC) and some potential biomarkers are introduced briefly. The review also discusses various strategies used in signal amplification such as nanomaterials, redox mediators, p19 protein, duplex specific nucleases (DSN) and redox cycling.