Carcinoembryonic Antigen Assay Research Articles

Verification of analytical performance of Carcinoembryonic antigen assay on the Abbott Alinity ci®: Experience of the central laboratory of Mohammed VI University Hospital of Oujda

Verification of analytical performance of Carcinoembryonic antigen assay on the Abbott Alinity ci®: Experience of the central laboratory of Mohammed VI University Hospital of Oujda

Dual-mode photothermal/chemiluminescence vertical flow assay for sensitive point-of-care detection of carcinoembryonic antigen using Cu2-xAgxS@liposome on a filter membrane

Conventional lateral flow assays based on colorimetry and fluorescence still have shortages in sensitivity and selectivity due to the severe background interference from complex human fluid sample matrices. In this work, Cu2-xAgxS nanocrystals with high photothermal conversion efficiency and good peroxidase-like activity were synthesized and applied in the construction of a dual-mode near-infrared-photothermal/chemiluminescence (CL) vertical flow assay of carcinoembryonic antigen (CEA). These two-mode principles showed nearly zero background and the synthesized Cu2-xAgxS exhibited a high photothermal conversion efficiency of 75.23%, enabling the luminol-H2O2 CL system to have over 4 min of chemiluminescence. By combining filter membrane enrichment, Cu2-xAgxS@liposome encapsulation amplification, and nanozyme catalysis, a dual-mode photothermal/CL portable assay was constructed for sensitive and accurate detection of CEA in serum, with linear ranges of 0.02–40 and 0.001–30 ng mL−1, and detection limits of 0.0023 and 0.00029 ng mL−1, respectively. Furthermore, a smartphone application and a 3D printing device were combined for point-of-care testing. This assay can be completed within 20 min, with simple operation and no need for large instruments. It exhibited good sensitivity, selectivity, and stability, and is expected to be used in early diagnosis and prevention of relevant diseases in resource-limited areas.

Abstract 3637: Ultrasensitive assays for combined detection of CEA+ extracellular vesicles and soluble CEA

Abstract Colorectal cancer (CRC) is the third most common cancer worldwide and is the second leading cause of cancer death in the United States. Carcinoembryonic antigen (CEA) is a biomarker commonly used in the management of CRC. It is typically present at low levels in the blood of healthy adults but is elevated in CRC samples and some other cancers. CEA is most commonly used to monitor treatment efficacy and as a critical part of post-treatment surveillance for residual disease, recurrence, and/or progression/metastasis. The CRC recurrence rate averages >25%, and liver metastasis occurs in 25-30% of cases. Improved CEA assays could enable earlier determination of treatment failure, detection of lower levels of minimal residual disease (MRD) after treatment, or earlier detection of recurrence. CEA is a GPI-linked membrane protein secreted from CRC cells mainly by enzymatic cleavage of its GPI anchor. However, we have identified alternative secretion of CEA in association with extracellular vesicles (EVs). We hypothesized that the soluble CEA produced by canonical shedding and the alternatively secreted CEA may provide distinct information about the tumor or its microenvironment and serve as independent but complementary biomarkers of CRC. We developed ultrasensitive, multi-marker electrochemiluminescence (ECL) immunoassays for measuring intact EVs presenting CEA, CD73, or both in human plasma. We observed that plasma levels of CEA+EVs and CD73+EVs were elevated in some late-stage CRC samples compared to controls. CEA and CD73 double-positive EV (CEA+CD73+EVs) levels were also elevated in the same samples, exhibiting a 3-fold improved separation of these samples with CRC from controls, compared to detection of CEA+EVs. Additionally, approximately 25% of stage IV CRC samples had elevated CEA+EV and CEA+CD73+EV levels while exhibiting low soluble CEA. We confirmed this result in an independent sample set that included samples across all CRC stages, and also identified a few earlier-stage samples that exhibited high CEA+EVs and CEA+CD73+EVs without elevated soluble CEA. Since CEA+CD73+EVs and soluble CEA assays identified different subsets of samples, we combined the two assays into a single classifier for late stage CRC and controls, yielding improved receiver operator characteristic (ROC) with area under the curve (AUC) of 0.975 versus 0.927 for the standard soluble CEA assay or 0.788 for CEA+CD73+EVs alone. These results suggest that assaying EVs presenting multiple surface markers can increase specificity for the detection of tumor-derived EVs relative to a single marker and that assaying both soluble and EV-associated forms of CEA in plasma may improve the value of CEA measurement in CRC. Citation Format: Lucie Hebert, Misk Al-Ameen, Talis Spriggs, Collin Nelson, Evan A. Gizzie, Jeffrey L. Franklin, Robert J. Coffey, David A. Routenberg, Jacob N. Wohlstadter. Ultrasensitive assays for combined detection of CEA+ extracellular vesicles and soluble CEA [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 3637.

Droplet-Based Preparation of ZnO-nanostructure Array for Microfluidic Fluorescence Biodetection.

Nanostructure-enhanced biodetection is widely used for early diagnosis and treatment, which plays an essential role in improving the cure rates of cancer patients. ZnO nanostructure-based fluorescence immunoassay has been demonstrated to enable effective and sensitive detection of cancer biomarkers for their excellent biocompatibility, high electrical point, and unique fluorescence enhancement properties. Further optimization of such fluorescence detection technology is still in demand to meet the requirements of highly sensitive, multiplex detection, and user-friendly devices. Droplet microfluidics is a promising platform for high-throughput analysis of biological assays, and they have been intensively used in analytical chemistry and synthesis of nanoparticles. Here, we propose a simple droplet chip, where a static droplet array was successfully obtained for in situ growth of ZnO nanostructures with varied diameters by changing the entire growth time and replenishment interval. This device provides a novel and alternative approach for patterned growth of ZnO nanostructures and understanding the growth condition of ZnO nanostructures in static droplet, which offers some guidance toward the design of multiple fluorescence amplification platforms potentially for biosensing. As a demonstration, we used the patterned grown ZnO nanostructures for multiple detection of cancer biomarkers, achieving a low limit of detection as low as 138 fg/mL in the human α-fetoprotein assay and 218 fg/mL in the carcinoembryonic antigen assay with a large dynamic range of 8 orders. These results suggest that such multifunctional microfluidic devices may be useful tools for efficient fluorescence diagnostic assays.

Application Value of CYFRA21-1 Combined with NSE, CEA, and SCC-Ag in Lung Cancer.

This study aims to investigate the application value of serum cytokeratin 19 fragment (CYFRA21-1) combined with nerve-specific enolase (NSE), carcinoembryonic antigen (CEA), and squamous cell carcinoma antigen (SCC-Ag) in the diagnosis of lung cancer (LC). A total of 831 cases of LC, 360 cases of benign lung disease (BLD) and 102 healthy controls, were enrolled. The data were processed using SPSS, GraphPad Prism, and MedCalc software. The tumor marker (TM) levels in the LC and BLD groups were significantly higher than those in the control group; the CYFRA21-1, NSE, and CEA levels in the patients with LC were higher than in those with BLD. In particular, the increase was predominantly observed for the levels of CEA and CYFRA21-1 in adenocarcinoma (LUAD), CYFRA21-1 and SCC-Ag in squamous cell carcinoma (LUSC), and NSE in small cell carcinoma (SCLC). The CYFRA21-1, NSE, and CEA levels were significantly higher in stage IV than in other stages in LC. Univariate binary logistic analysis showed that increased levels of all four TMs were risk factors for BLD and LC. The area under the curve (AUC) of CYFRA21-1 was most effective in distinguishing patients with BLD or LC from the controls and in distinguishing patients with BLD and LC. The AUCs of combined CYFRA21-1, NSE, and CEA were increased to 0.755, 0.922, and 0.783, respectively, with no significant difference with the AUC of the four combined tests. In the histological classification, the best predictors were CEA, for LUAD, CYFRA21-1 for LUSC, and NSE for SCLC. Moreover, the expression levels of CYFRA21-1, NSE, and CEA significantly decreased after each treatment course. The combined assay of CYFRA21-1, NSE, and CEA addresses the aspects of accuracy, sensitivity, specificity, and economic cost and should be considered as a potential diagnostic test in LC.

A simplified lateral flow immunosensor for the assay of carcinoembryonic antigen in low-resource settings.

Carcinoembryonic antigen (CEA) is a glycoprotein widely used as a tumor marker. In this work, a colorimetric lateral flow immunosensor is developed for rapid and low-cost quantification of CEA in human blood serum. The immunosensor consists of a glass fiber sample/conjugation pad, a nitrocellulose detection pad and a cellulose absorption pad. The detection is based on a sandwich immunoreaction: the sample/conjugation pad is modified with gold nanoparticles (GNPs)-labeled anti-CEA conjugate probes which bind to the CEA target molecules in the sample and the complexes are captured at capture anti-CEA immobilized at the test line. The color intensity of the test line, measured from a scanned image of the strip, is related to the CEA concentration in the sample. The different assay parameters are studied in detail. The linearity holds from 1.25 to 640 ng mL-1 of CEA, the instrumental and visual limits of detection are 0.45 and 0.63 ng mL-1, respectively, and the total assay time is 15 min. The specificity of the immunoassay versus other cancer biomarkers is satisfactory. The recovery in samples of human serum spiked with CEA is in the range of 81-118% and the coefficient of variation of the method is ≤10%. Results obtained with the lateral flow immunosensor correlated well with a reference radioimmunoassay method (R2 = 0.99). This immunosensor can be readily applied to CEA monitoring at the point-of-care (POC) or in resource-limited settings thanks to its low-cost and simplicity.

Optimal carcinoembryonic antigen (CEA) cutoff values in the diagnosis of neoplastic mucinous pancreatic cysts differ among assays

AimPancreatic cyst fluid carcinoembryonic antigen (CEA) is a pivotal test in the diagnosis and management of neoplastic mucinous cysts (NMC) of the pancreas. Cyst fluid CEA levels of 192 ng/mL...

B-379 Analytical Performance of Two Tumor Marker Immunoassays on the Atellica CI 1900 Analyzer

Abstract Background The Atellica® CI 1900 Analyzer is an automated, mid-throughput, integrated chemistry and immunoassay analyzer utilizing both Atellica CH and Atellica IM assays. This study was designed to evaluate the analytical performance of the Atellica IM Carcinoembryonic Antigen (CEA) and Alpha Fetoprotein (AFP) assays* on the Atellica CI 1900 Analyzer. Methods The Atellica CI 1900 CEA and AFP assays use the same reagents and calibrators as the comparable Atellica IM assays. Precision and method comparison (MC) were used as performance indicators for the Atellica CI 1900 Analyzer. Precision studies were performed according to CLSI EP05-A3 using quality control, native, and contrived human serum samples. One aliquot of each sample pool was tested in duplicate in two runs per day ≥2 h apart on each analyzer for ≥20 days. MC studies were performed according to CLSI EP09-A3. Individual native and contrived human serum samples were analyzed using the Atellica IM assays on both the Atellica IM and Atellica CI 1900 Analyzers. Results Representative precision and MC results observed for each assay across indicated sample ranges are listed in the table. Slopes determined by the Deming linear regression model were approximately equal to 1. Conclusion Evaluation of the CEA and AFP assays using the Atellica CI 1900 Analyzer demonstrated good precision and equivalent performance compared to the same assays on the Atellica IM Analyzer. *The products/features mentioned here are not commercially available in all countries. Their future availability cannot be guaranteed.

Gold Nanotapes and Nanopinecones in a Quantitative Lateral Flow Assay for the Cancer Biomarker Carcinoembryonic Antigen.

Colorectal cancer is the third most common malignancy and the second leading cause of cancer death globally. Multiple studies have linked levels of carcinoembryonic antigen in patient serum to poor disease prognosis. Hence, the ability to detect low levels of carcinoembryonic antigen has applications in earlier disease diagnosis, assessment, and recurrence monitoring. Existing carcinoembryonic antigen detection methods often require multiple reagents, trained operators, or complex procedures. A method alleviating these issues is the lateral flow assay, a paper-based platform that allows the detection and quantification of target analytes in complex mixtures. The tests are rapid, are point-of-care, possess a long shelf life, and can be stored at ambient conditions, making them ideal for use in a range of settings. Although lateral flow assays typically use spherical gold nanoparticles to generate the classic red signal, recent literature has shown that alternate morphologies to spheres can improve the limit of detection. In this work, we report the application of alternative gold nanoparticle morphologies, gold nanotapes (∼35 nm in length) and gold nanopinecones (∼90 nm in diameter), in a lateral flow assay for carcinoembryonic antigen. In a comparative assay, gold nanopinecones exhibited a ∼2× improvement in the limit of detection compared to commercially available spherical gold nanoparticles for the same antibody loading and total gold content, whereas the number of gold nanopinecones in each test was ∼3.2× less. In the fully optimized test, a limit of detection of 14.4 pg/mL was obtained using the gold nanopinecones, representing a 24-fold improvement over the previously reported gold-nanoparticle-based carcinoembryonic antigen lateral flow assay.

Building of a three-dimensional apta-nano interface using silver nanoflower for photoelectrochemical detection of carcinoembryonic antigen

Enhancing the sensitivity of photoelectrochemical (PEC) assays poses a challenging task. This study proposes a method to improve the sensitivity of PEC assays by creating a three-dimensional (3D) apta-nano interface using silver nanoflowers (AgNFs) with a 3D flower-like structure as a substrate. The aptamer (Apt) was immobilized on the surface of the AgNF-loaded gold nanoparticles (AuNPs) through the dual action of polyA blocking and Au-S bonding. Despite using cadmium sulfide quantum dots (CdS QDs) as the sole photoactive material, the as-prepared photoelectrode still showed excellent sensitivity. Using carcinoembryonic antigen (CEA) as a model target, the variation value of photocurrent (ΔI) exhibited good linear correlation (R2 = 0.9974) with the logarithm of CEA concentration in a wide detection range from 0.001 to 100 ng mL−1, and the detection limit was as low as 0.64 pg mL−1. In the assay of CEA in 1% serum, the recoveries reached 98.70 ∼ 99.63% with a low relative standard derivation (RSD) ranging from 1.11% to 2.05%. This study introduces novel concepts for the development of PEC sensors, potentially enhancing their utility in the clinical detection of disease markers.

A dual-model immobilization-free photoelectrochemical/visual colorimetric bioanalysis based on microemulsion self-assemblies mediated multifunctional signal amplification strategy

Herein, a novel silver ion-loaded gold microemulsion assemblies (Au/Ag+ MAs) mediated multifunctional signal amplification strategy was proposed to construct a sensitive immobilization-free photoelectrochemical (PEC)/colorimetric biosensor for carcinoembryonic antigen (CEA) detection. Through the sandwiched reaction among CEA, the CEA aptamer (DNA1) loaded on the Au nanoparticles (NPs) functionalized iron oxide (Fe3O4) nanospheres and another CEA aptamer (DNA2) immobilized on Au/Ag+ MAs, a complex is formed and acquired by magnetic separation. Then, Au/Ag+ MAs of the complex are disassembled into Au NPs and Ag+ ions driven by an acetone response, and the obtained demulsification solution is transferred to the cadmium sulfide/cadmium telluride (CdS/CdTe) photoactive composites modified electrode. Based on the multiple inhibition functions (blocking effect of oleylamine; energy transfer effect of Au NPs; and electron snatching effect of Ag+), the photocurrent of the electrode decreases obviously, resulting in the ultrasensitive detection of CEA (a detection limit of 16 fg mL−1). Interestingly, the ion-exchange reactions between CdS/CdTe composites and Ag+ ions generate silver sulfide/silver telluride (Ag2S/Ag2Te) composites, and a color change of composites can be distinguished directly, leading to a quick visual detection of CEA. Compared with the traditional single-modal assay for CEA, such dual-modal PEC/colorimetric assay is a more accurate and reliable due to different mechanisms and independent signal conversion. This work will offer a new perspective for the applications of various self-assemblies in PEC bioanalysis.

Two-dimensional substrate assisted SERS immunosensor for accurate detection of carcinoembryonic antigen

Accurate and sensitive detection of carcinoembryonic antigen (CEA) is essential for the detection of various diseases in healthcare and the medical field. Currently, due to the high false negative rate of CEA assay in clinical setting and its use as a common indicator for early cancer screening, a novel CEA detection method with high sensitivity, increased specificity and the lower cost has become a clinical challenge. Here, a facile sandwich type immunosensor based on surface-enhanced Raman scattering (SERS) was presented including 4-mercaptobenzonitrile (4MBN) labeled gold core-silver shell nanoparticles (Au@4MBN@Ag NPs) as SERS tag and 4-mercaptophenylboronic acid (4-MPBA) functionalized two-dimensional (2D) silver nanoparticle film (Ag FM) as SERS capture substrate for CEA detection. A linearity of 10-9-10-14M was observed with high sensitivity and excellent selectivity for the detection of CEA. Additionally, the spiking experiment yielded 105.33–127.00% recovery with variation coefficients below 10% demonstrating high assay accuracy and precision. The immunosensor we proposed here is a promising approach to quantify CEA in liquid biopsy samples with high sensitivity, which could be further developed for early cancer screening.

Immobilization-free electrochemical homogeneous aptasensor for highly sensitive detection of carcinoembryonic antigen by dual amplification strategy

Electrochemical aptasensor has been widely studied, while its practical application is limited by the unavoidable variations of aptamer loading densities and low signal amplification efficiency. To overcome these restrictions, an immobilization-free and label-free electrochemical homogeneous aptasensor was constructed for carcinoembryonic antigen (CEA) assay by combining RecJf exonuclease-mediated target cycling strategy and rolling circle amplification technology. In this system, the pre-immobilization of aptamers or other relevant signal elements on the electrode substrate is no longer necessary, thus the electrochemical homogeneous aptasensor shows good versatility on different transducers. Moreover, the whole recognition and signal amplification process are activated instantaneously by a non-professional operation of the solution mixture. This strategy can not only increase the stability (95.1% after 30 days of storage) and reproducibility (2.12% among five independent electrodes), but also further improve the sensitivity (detection limit of fg mL−1 level) due to the free target recognition and dual signal amplification in the homogeneous solution phase. The proposed immobilization-free electrochemical homogeneous aptasensors on different electrode substrates both achieve satisfactory results in actual sample tests, which has the potential for commercial applications and the establishment of other target platforms in the future.

An NIR light-responsive “on-off-on” photoelectrochemical aptasensor for carcinoembryonic antigen assay based on Y-shaped DNA

This work develops a novel photoelectrochemical sensor for the detection of carcinoembryonic antigen (CEA) based on the composite of UCNPs with semiconductors and conformational changes in the DNA structure. Firstly, SnS2, ZnIn2S4 and UCNPs were assembled on the surface of the ITO electrode. Then Au NPs were dropped, which could facilitate the coupling of CdSe NPs modified DNA1 via Au-S bond, giving an ITO/SnS2/ZnIn2S4/UCNPs/CdSe heterojunction structure. When irradiated with 980nm near-infrared (NIR) light, the UV-visible light emitted by the UCNPs could excite the nanocomposite, producing an enhanced photoelectric reaction. Subsequently, CEA aptamer and DNA2-modified SiO2 were added to form a Y-shaped DNA structure. At this time, the photocurrent was significantly reduced by the combination of the light-blocking effect of SiO2 and the departure of CdSe NPs from the electrode surface. When the target CEA was added, the recognition between CEA and the aptamer led to the collapse of the Y-shaped DNA structure, the restoration of hairpin DNA and the proximity of CdSe to the electrode. Accordingly, the photocurrent signals enhanced again. Under optimal experimental conditions, the detection limit as low as 0.3pgmL-1 was obtained with good selectivity, achieving a sensitive "on-off-on" photoelectrochemical sensor for CEA detection.

Ultrasensitive “on-off-on” photoelectrochemical aptasensor for tumor biomarker using BiOI/α-Fe2O3 p-n heterojunction arrays by in-situ regulation of electron donor distance

Precise assay of carcinoembryonic antigen (CEA) is of paramount significance for the diagnosis, treatment, and prognosis of related cancers. Herein, an ultrasensitive “on-off-on” photoelectrochemical (PEC) aptasensor for CEA assay was proposed based on BiOI/α-Fe2O3 p-n heterojunction arrays by in-situ regulation of electron donor distance. The synthesized BiOI/α-Fe2O3 nanosheet arrays (BiOI/α-Fe2O3 NSAs) were served as photoactive materials, and the special structure facilitates considerably the immobilization of biomolecules. Ferrocene-modified hairpin DNA (Fc-hDNA), as the biorecognition elements and electron donor, was used to bond with CEA aptamer and offer electrons. The distance between Fc and BiOI/α-Fe2O3 NSAs interface can be effectively regulated through the specific recognition of Fc-hDNA and CEA aptamer, which also exhibited an “on-off-on” PEC sensoring model towards the detection of CEA. This method exhibited a wide linear range from 1.0 × 10−4 to 20 ng mL−1, with a low detection limit of 36.89 fg mL−1 for CEA detection. The developed PEC aptasensor has achieved satisfactory results in serum samples, also provide a novel perspective for other disease marker assay.

Study of carcinoembryonic antigen tumor marker in gastrointestinal pathology

Background: Cancer mortality and morbidity has been increased in recent years, with gastrointestinal cancers comprising the majority of overall malignant conditions. All Indian cancer registries identify the digestive system as the most common cancer site in males. In women, breast cancer exhibits the highest occurrence, followed by cancers of the genital organs and the digestive system. Tumor markers are usually proteins or glycoproteins produced by the body in response to cancerous growth or by the cancer tissue that are possible to detect in serum, urine, or tissue samples. CEA assay is an inexpensive and easy to perform test; however, repeated measurements to monitor disease, follow up and the response to therapy contribute to higher costs and increase laboratory workload. Materials and Methods: The present study was carried out on 100 patients. Type of sample includes blood sample in plain vacutte received in tumor marker section of the pathology department. Objective: To make a comparative analysis of CEA in various gastrointestinal lesions.  Pre and post operative study of Serum CEA in known case of gastrointestinal carcinoma.  To study the factors affecting serum CEA concentrations. Results: The present study was conducted from June 2018 to December2020 in the Department of Pathology, at tertiary care hospital, 100 cases were studied. Preoperative and postoperative mean CEA value, Mean CEA value in inflammatory, Benign and Malignant lesions as well as in well, moderately and poorly differentiated carcinoma were measured.Conclusion: In general, this study showed that serum CEA levels are increased in people with habit of cigarette smoking and in benign and inflammatory lesions of GIT along with Malignant GI lesions. Carcinoembryonic antigen (CEA) usually normalizes after surgery. After curative resection of primary CRC (colorectal carcinoma), a large number of patients' CEA levels declined to normal values within 4-6 weeks. Amongst many contradictory results, the measurement of CEA is a useful method for screening, diagnosis, follow-up and treatment of CRC but Physiological influences that need to be considered in interpreting the results include effects of aging and smoking. Serum CEA values fails to decline in patients with distant metastasis and advanced disease even after complete surgical removal of the tumour. Serum concentrations of CEA tend to be higher in patients with well-differentiated tumors compared with those with poorly differentiated tumors.

Band-Edge Effect-Induced Electrochemiluminescence Signal Amplification Based on Inverse Opal Photonic Crystals for Ultrasensitive Detection of Carcinoembryonic Antigen.

Photonic crystals (PCs) have emerged as a promising electrochemiluminescence (ECL) matrix in the domain of immunoassay. Making maximum use of light manipulation properties of PCs is highly desired for improving the sensitivity. In this work, we proposed a band-edge effect-induced ECL enhancement strategy based on silica inverse opal PCs (SIOPCs). By fine-tuning the lattice constant and carefully calibrating the stopband position, we found that the band edge of the stopband exerted significant influences on the ECL intensity and spectral distribution. The high density of states at the blue edge of the photonic band gap increased the radiative transition probability of ECL emitters and enhanced the photon extraction during propagation, giving rise to ∼20-fold ECL signal amplification accompanied by a redistributed ECL spectrum for the Ru(bpy)32+-TPrA system. In combination with the intrinsic structural superiority, like large specific surface area and interconnected macropores, the developed SIOPC electrode was successfully applied in constructing a sandwich-type immunosensor. The fabricated immunosensor displayed a very low detection limit of 0.032 pg/mL and a wide linear range of 0.1 pg/mL-150 ng/mL for a carcinoembryonic antigen assay, showing its potential application in disease diagnosis.

Handheld pH‐Meter‐based Electrochemical Aptasensing of Carcinoembryonic Antigen on Multifuctional Magnetic Beads

AbstractMethods derived from immunoassays and aptasensors have been established for monitoring of carcinoembryonic antigen (CEA) in biological fluids, but most involved complex procedure and various reactions. We designed an uncomplicated and convenient electrochemical aptasensing platform for the quantitative monitoring of CEA on multifunctionalized magnetic beads with a handheld pH meter as the read‐out. Initially, CEA‐specific aptamers were covalently conjugated to magnetic beads, and then hybridized with glucose oxidase‐labeled complementary strands to construct multifunctional nanoprobes. After addition of target CEA, the analyte interacts with the corresponding aptamer and then release the complementary strand. After magnetic separation, the released glucose oxidase‐labeled complementary strands hydrolysed glucose, thereby leading to a change in pH of the detection solution, which was quantitatively monitored on a hand‐held pH meter. Under the optimum conditions, the aptasensor based on pH meter exhibited well responses relative to CEA concentrations inside the dynamic range between 0.01 and 100 ng mL−1 and detection limit at least 9.3 pg mL−1. Good duplicability, high specificity and ability for long‐term stable storage are obtained for the as‐prepared aptasensors. Additionally, human serum specimens were determined through pH‐meter‐based aptasensors, and the results closely matched the commercial enzyme‐linked immunosorbent assay (ELISA) of human CEA.

Application Value of Serum TK1 and PCDGF, CYFRA21-1, NSE, and CEA plus Enhanced CT Scan in the Diagnosis of Nonsmall Cell Lung Cancer and Chemotherapy Monitoring

Objective To assess the application value of serum thymidine kinase 1 (TK1) and PC cell-derived growth factor (PCDGF), cytokeratin 19 fragment 21-1 (CYFRA21-1), neuron-specific enolase (NSE), and carcinoembryonic antigen (CEA) plus enhanced CT scan in the diagnosis of nonsmall cell lung cancer (NSCLC) and chemotherapy monitoring. Methods Between April 2019 and April 2021, 30 patients with NSCLC assessed for eligibility treated in our institution were included in the experimental group, and 30 healthy individuals screened out from physical examinations were recruited in the control group. The chemotherapy regimens included gemcitabine plus cisplatin, pemetrexed disodium plus cisplatin, and vinorelbine plus cisplatin. The application value of serum TK1, PCDGF, CYFRA21-1, NSE, CEA, and enhanced CT scan in the diagnosis and chemotherapy monitoring of NSCLC was analyzed. Results Before treatment, the eligible patients had significantly higher serum levels of TK1, PCDGF, CYFRA21-1, NSE, and CEA than those of the healthy individuals included (P < 0.05). Clinical efficacy was categorized into good and poor, and the good efficacy included complete response and partial response, with the poor efficacy including stable disease and progressive disease. Patients with good clinical efficacy had lower levels of serum TK1, PCDGF, CYFRA21-1, NSE, and CEA than those with poor efficacy (P < 0.05). Joint detection showed a larger area under the curve (AUC) (0.900; 95%CI, 0.812-0.988), a higher sensitivity, and a superior detection outcome to the stand-alone detection (P < 0.05). Diagnostic results were similar between joint detection and pathological examination (P > 0.05). Conclusion The application of serum TK1, PCDGF, CYFRA21-1, NSE, and CEA assay plus enhanced CT scan shows high sensitivity and diagnostic accuracy in the diagnosis and chemotherapy monitoring of nonsmall cell lung cancer and thus provides a diagnostic reference basis.

Fast screening method for early diagnostic of gastric cancer based on utilization of a chitosan – S-doped graphene - based needle stochastic sensors

Needle stochastic sensors were developed for the assay of carbohydrate antigen 19–9 (CA 19–9) and carcinoembryonic antigen (CEA) in different biological samples (e.g., whole blood, tissues, urine, and saliva). Sulfur doped graphene powders were modified with chitosan; paraffin oil was added to form a homogeneous paste that was used as active side of the stochastic sensors. High sensitivities and low limits of determination were achieved for the assay of CA19-9 and CEA in biological samples. The validation of the proposed screening method (which is utilizing the stochastic sensors as screening tools) was made by using real biological samples obtained from confirmed patients with gastric cancer; very good correlations for the concentrations of CEA and CA19-9 were obtained using the needle stochastic sensors.