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1.
Luminescence ; 39(6): e4804, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38859763

RESUMO

Early and sensitive detection of tobacco mosaic virus (TMV) is of great significance for improving crop yield and protecting germplasm resources. Herein, we constructed a novel fluorescence sensor to detect TMV RNA (tRNA) through double strand specific nuclease (DSN) cycle and activator regenerative electron transfer atom transfer radical polymerization (ARGET ATRP) dual signal amplification strategy. The hairpin DNA complementarily paired with tRNA was used as a recognition unit to specifically capture tRNA. By the double-stranded DNA hydrolyzed with DSN, tRNA is released to open more hairpin DNA, and more complementary DNA (cDNA) is bound to the surface of the magnetic beads (MBs) to achieve the first amplification. After binding with the initiator, the cDNA employed ARGET ATRP to attach more fluorescent signal molecules to the surface of MBs, thus achieving the second signal amplification. Under the optimal experimental conditions, the logarithm of fluorescence intensity versus tRNA concentration showed a good linear relationship in the range of 0.01-100 pM, with a detection limit of 1.03 fM. The limit of detection (LOD) was calculated according to LOD = 3 N/S. Besides, the sensor showed good reproducibility and stability, which present provided new method for early and highly sensitive detection for plant viruses.


Assuntos
RNA Viral , Vírus do Mosaico do Tabaco , Vírus do Mosaico do Tabaco/genética , Vírus do Mosaico do Tabaco/química , RNA Viral/análise , Fluorescência , Limite de Detecção , Técnicas Biossensoriais/métodos , Corantes Fluorescentes/química , Espectrometria de Fluorescência
2.
Mikrochim Acta ; 191(6): 348, 2024 05 28.
Artigo em Inglês | MEDLINE | ID: mdl-38805077

RESUMO

A novel aptamer-based sensor was developed using the signal amplification strategy of ring-opening metathesis polymerization (ROMP) and polyethyleneimine modified graphene oxide to achieve trace detection of carbendazim (CBZ). The dual identification of aptamer and antibody was used to avoid false positive results and improve the selectivity. Polyethyleneimine modified graphene oxide (GO-PEI), as a substrate material with excellent conductivity, was modified on the surface of a glassy carbon electrode (GCE) to increase the grafting amount of aptamer on the electrode surface. Moreover, a large number of cyclopentenyl ferrocene (CFc) was aggregated to form long polymer chains through ring-opening metathesis polymerization (ROMP), so as to significantly improve the detection sensitivity of the biosensor. The linear range of this sensor was 1 pg/mL-100 ng/mL with a detection limit as low as 7.80 fg/mL. The sensor exhibited excellent reproducibility and stability, and also achieved satisfactory results in actual sample detection. The design principle of such a sensor could provide innovative ideas for sensors in the detection of other types of targets.


Assuntos
Aptâmeros de Nucleotídeos , Benzimidazóis , Técnicas Biossensoriais , Carbamatos , Técnicas Eletroquímicas , Grafite , Limite de Detecção , Polietilenoimina , Polimerização , Grafite/química , Carbamatos/química , Carbamatos/análise , Técnicas Eletroquímicas/métodos , Técnicas Eletroquímicas/instrumentação , Polietilenoimina/química , Técnicas Biossensoriais/métodos , Benzimidazóis/química , Aptâmeros de Nucleotídeos/química , Eletrodos , Reprodutibilidade dos Testes
3.
J Mater Chem B ; 12(24): 5861-5868, 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38775046

RESUMO

The development of a simple, rapid, and sensitive technology for the simultaneous detection of mycotoxins is of great significance in ensuring the safety of foods and drugs. Herein, a fluorescence aptasensor with high sensitivity and reproducibility for the simultaneous detection of aflatoxin B1 (AFB1) and ochratoxin A (OTA) was developed. In this sensing system, AFB1 and OTA aptamers were co-immobilized on the surface of magnetic beads (MBs) to form a Y-shaped structure through the principle of complementary base pairing, and were used as recognition probes to specifically capture the target. Activators regenerated by electron transfer for atom transfer radical polymerization (ARGET ATRP) was used as a signal amplification strategy to improve the sensitivity. The initiator modified at the end of an antibody initiates the ARGET ATRP reaction. Different fluorescence signals were designed to achieve the simultaneous detection of OTA and AFB1 with limits of 426.18 and 79.55 fg mL-1 for AFB1 and OTA, respectively. In addition, experiments were conducted on three types of samples, and the recoveries of the two mycotoxins ranged from 87.30% to 109.50%, with relative standard deviations ranging from 0.50% to 4.92% under reproducible conditions. The results suggest that the developed aptasensor is sufficient to meet the different regulatory requirements of the two mycotoxins in food and drug safety and shows great potential.


Assuntos
Aflatoxina B1 , Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Ocratoxinas , Aflatoxina B1/análise , Ocratoxinas/análise , Aptâmeros de Nucleotídeos/química , Técnicas Biossensoriais/métodos , DNA/química , Polimerização , Limite de Detecção , Transporte de Elétrons
4.
Noise Health ; 26(120): 19-24, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38570306

RESUMO

BACKGROUND: Patients undergoing total knee arthroplasty (TKA) need to tolerate the effects of noise. MATERIALS AND METHODS: This study retrospectively analyzed the clinical data of 167 TKA patients at The Affiliated Hospital of Southwest Medical University from April 2019 to April 2021. A total of 154 patients who met inclusion criteria were divided into the conventional noise reduction management group (CMG) and the noise reduction earplug group (EPG), following different management schemes. The CMG received routine noise reduction management after surgery, while the EPG used noise reduction earplugs based on the CMG. The clinical indexes of the two groups were compared. RESULTS: In this study, 79 patients were included in the CMG, and 75 patients were included in the EPG. The results showed that the Pittsburgh Sleep Quality Index (PSQI) scores of both groups 2 weeks after surgery were significantly lower than those before management (ZEPG = 5.995, ZCMG = 4.109, all P < 0.001), and the EPG exhibited a significantly lower PSQI score than the CMG (Z = -2.442, P < 0.05). Two weeks after surgery, the EPG had significantly lower levels of systolic blood pressure (ZSBP = -4.303) and diastolic blood pressure (ZDBP = -3.115), as well as lower scores on the Hospital Anxiety and Depression Scale-Anxiety (HADS-A; ZHADS-A = -7.140) and Hospital Anxiety and Depression Scale-Depression (HADS-D; ZHADS-D = -4.545) compared to the CMG (all P < 0.05). In addition, no significant correlation existed between the duration of wearing earplugs and the HADS-A and HADS-D scores (r = -0.201, r = -0.002, P > 0.05). CONCLUSION: Noise reduction earplugs can improve sleep quality and regulate negative emotions of patients undergoing TKA treatment through a complex mechanism involving noise, which is beneficial to the prognosis of the disease.


Assuntos
Artroplastia do Joelho , Humanos , Estudos Retrospectivos , Dispositivos de Proteção das Orelhas , Ruído/efeitos adversos
5.
Talanta ; 275: 126130, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38653117

RESUMO

Human epidermal growth factor receptor 2 (HER2), a common proto-oncogene, is overexpressed in a subset of breast cancer patients. It is essential to track HER2 expression for early breast cancer diagnosis. Herein, a ratiometric electrochemical biosensor for detection of HER2 based on activators generated by electron transfer for atom transfer radical polymerisation (AGET ATRP) and hairpin DNA was developed. Specifically, hairpin DNA was first self-assembled on the gold electrode by Au-S bond. Upon capturing HER2, the stem-loop structure of hairpin DNA was unfolded, the signal value of methylene blue (MB) decreased as it moved away from the electrode surface. cDNA was linked with HER2 by complementary base pairing to introduce amino group. Then, the initiator 2-bromo-2-methylpropionic acid (BMP) were connected to the amino group on the cDNA to activate ARGET ATRP. The detection performance of biosensors for HER2 was explored by the ratio signal between two signal molecules. Under optimal conditions, this ratiometric electrochemical biosensor shows good selectivity and stability with a wide detection range of 1-1 × 106 pM and a detection limit of 78.47 fM. Furthermore, the biosensor exhibits satisfactory anti-interference ability due to the hairpin DNA and dual signal system, and has promising application prospects in the detection of other DNA disease markers.


Assuntos
Técnicas Biossensoriais , Técnicas Eletroquímicas , Proto-Oncogene Mas , Receptor ErbB-2 , Técnicas Biossensoriais/métodos , Receptor ErbB-2/genética , Humanos , Técnicas Eletroquímicas/métodos , Eletrodos , Ouro/química , Limite de Detecção , Polimerização , DNA/química , DNA/genética
6.
Chempluschem ; : e202400119, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38619207

RESUMO

Down-regulator of transcription 1 (DR1) is considered as a biomarker of hashimoto's thyroiditis (HT), which is a risk factor for thyroid cancer. Here, a label-free electrochemical biosensor for DR1 detection was constructed based on polyamidoamine (PAMAM) polymer and the nanocomposite (WO3@AuNPs) composed of tungsten trioxide (WO3) and gold nanoparticles (AuNPs). WO3@AuNPs was obtained by combining monolayer WO3 nanosheets, which has high conductivity, and AuNPs. The modification of WO3@AuNPs can not only increase the conductivity of the electrode but also provide more active sites for signaling units, thus greatly improve the sensitivity of the sensor. The polymer PAMAM is biocompatible and non-immunogenic, and its end functional group can bind to the target molecules, providing them with more binding sites and thus improving the sensitivity of the sensor. Under optimal conditions, the label-free biosensor showed a good linear relationship between the logarithm of DR1 concentration and the impedance in the range of 10 fg ⋅ mL-1 to 100 ng ⋅ mL-1, with a detection limit as low as 0.3 fg ⋅ mL-1. Besides, this label-free electrochemical platform exhibited satisfactory selectivity and anti-interference capability in human serum samples. Therefore, this method has considerable potential in clinical detection of DR1.

7.
Mikrochim Acta ; 191(3): 148, 2024 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-38374311

RESUMO

A unique combination of a specific nucleic acid restriction endonuclease (REase) and atom transfer radical polymerization (ATRP) signal amplification strategy was employed for the detection of T790M mutations prevalent in the adjuvant diagnosis of lung cancer. REase selectively recognizes and cleaves T790M mutation sites on double-stranded DNA formed by hybridization of a capture sequence and a target sequence. At the same time, the ATRP strategy resulted in the massive aggregation of upconverted nanoparticles (UCNPs), which significantly improved the sensitivity of the biosensor. In addition, the UCNPs have excellent optical properties and can eliminate the interference of autofluorescence in the samples, thus further improving the detection sensitivity. The proposed upconversion fluorescent biosensor is characterized by high specificity, high sensitivity, mild reaction conditions, fast response time, and a detection limit as low as 0.14 fM. The performance of the proposed biosensor is comparable to that of clinical PCR methods when applied to clinical samples. This work presents a new perspective for assisted diagnosis in the pre-intervention stage of tumor diagnostics in the early stage of precision oncology treatments.


Assuntos
Técnicas Biossensoriais , Neoplasias Pulmonares , Humanos , Neoplasias Pulmonares/genética , Enzimas de Restrição do DNA , Receptores ErbB/genética , Polimerização , Clivagem do DNA , Limite de Detecção , Mutação , Medicina de Precisão , Inibidores de Proteínas Quinases , Técnicas Biossensoriais/métodos
8.
Mikrochim Acta ; 190(11): 432, 2023 10 09.
Artigo em Inglês | MEDLINE | ID: mdl-37806989

RESUMO

An ochratoxin A (OTA) electrochemical biosensor based on a cascade signal amplification strategy with Ag nanoparticles (AgNPs) and ring opening polymerization (ROP) was constructed. The large specific surface area of AgNPs was used to increase the loading of OTA aptamer on the electrode surface, enhancing the ability to capture OTA as a way to achieve the first signal amplification. The OTA antibody modified with polyethylenimine specifically recognizes the OTA, forming an aptamer-OTA-antibody sandwich structure. The amino group on polyethylenimine initiates the ROP reaction with α-amino acid-n-carboxylic anhydride-ferrocene (NCA-Fc) as the monomer. A large number of electrochemical signal units of ferrocene are introduced into the sensing system for a second signal amplification. By amplifying the signal twice, the sensitivity of the sensor is improved. Under the optimal conditions, the detection range of the sensor is 1 pg·mL-1 ~ 1 µg·mL-1, while the detection limit is as low as 117 fg·mL-1. Moreover, the sensor has the advantages of high sensitivity, good stability and selectivity. Standard addition recovery experiment proved that the sensing system can be successfully used for the detection of OTA in four actual samples with recoveries in the range 90.0 to 113% with RSDs of 0.6 to 5.2%, providing a new idea for the pollution assessment of mycotoxins.


Assuntos
Técnicas Biossensoriais , Nanopartículas Metálicas , Metalocenos/química , Nanopartículas Metálicas/química , Polietilenoimina , Polimerização , Técnicas Eletroquímicas , Prata
9.
Chemistry ; 29(65): e202301602, 2023 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-37622405

RESUMO

The levels of KRAS G12C point mutation is recognized to be closely related to the earlier diagnosis of non-small cell lung cancer (NSCLC). Here, based on nitrogen-doped graphene quantum dots (NGQDs) and photo-induced electron/energy transfer reversible addition-fragment chain transfer (PET-RAFT) signal amplification strategy, we fabricated a novel electrochemiluminescence (ECL) biosensor for the detection of KRAS G12C mutation for the first time. NGQDs as ECL-emitting species with cathodic ECL were prepared by a simple calcination method. Firstly, KRAS G12C mutation DNA, i. e., target DNA (tDNA), was captured by specific identification with hairpin DNA (hDNA). Then, PET-RAFT was initiated by blue light, and large numbers of monomers were successfully polymerized to form controllable polymer chains. Lastly, massive NGQDs was introduced via amidation reaction with N-(3-aminopropyl)methacrylamide hydrochloride (APMA), which significantly amplified the ECL signal intensity. Under optimal conditions, this biosensor achieved a good linear relationship between ECL intensity and logarithm of the levels of KRAS G12C mutation in the range from 10 fM to 10 nM. Moreover, this strategy exhibited high selectivity and excellent applicability for KRAS G12C mutation detection in the serum samples. Therefore, this biosensor has great potential in clinical diagnosis and practical application.


Assuntos
Técnicas Biossensoriais , Carcinoma Pulmonar de Células não Pequenas , Grafite , Neoplasias Pulmonares , Pontos Quânticos , Humanos , Proteínas Proto-Oncogênicas p21(ras)/genética , Nitrogênio , Medições Luminescentes/métodos , DNA , Técnicas Biossensoriais/métodos , Mutação , Tomografia por Emissão de Pósitrons
10.
Talanta ; 262: 124659, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37220688

RESUMO

Accurate and ultrasensitive detection of cytokeratin 19 fragment (CYFRA21-1) is of vital importance for screening and diagnosis of potential lung cancer patient. In this paper, surface-modified upconversion nanomaterials (UCNPs) capable of aggregation by atom transfer radical polymerization (ATRP) were used as luminescent materials for the first time to achieve signal-stable, low-biological background, and sensitive detection of CYFRA21-1. Upconversion nanomaterials (UCNPs) feature extremely low biological background signals and narrow emission peaks, making them ideal sensor luminescent materials. The combination of UCNPs and ATRP not only improves sensitivity, but also reduces biological background interference for detecting CYFRA21-1. The target CYFRA21-1 was captured by specific binding of the antigen and the antibody. Subsequently, the end of the sandwich structure with the initiator reacts with monomers modified on UCNPs. Then, massive UCNPs are aggregated by ATRP that amplify the detection signal exponentially. Under optimal conditions, a linear calibration plot of the logarithm of CYFRA21-1 concentration versus the upconversion fluorescence intensity was obtained in the range of 1 pg/mL to 100 µg/mL with a detection limit of 38.7 fg/mL. The proposed upconversion fluorescent platform can distinguish the analogues of the target with excellent selectivity. Besides, the precision and accuracy of the developed upconversion fluorescent platform were verified by clinical methods. As an enhanced upconversion fluorescent platform of CYFRA21-1, it is expected to be useful in screening potential patients with NSCLC and provides a promising solution for the high-performance detection of other tumor markers.


Assuntos
Técnicas Biossensoriais , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Nanopartículas , Humanos , Antígenos de Neoplasias , Queratina-19 , Neoplasias Pulmonares/diagnóstico , Técnicas Biossensoriais/métodos , Limite de Detecção , Nanopartículas/química
11.
Food Chem ; 421: 136176, 2023 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-37098309

RESUMO

An electrochemical sensor based on environmentally friendly eRAFT polymerization was developed for the detection of aflatoxin B1 (AFB1) in food and herbal medicine. Two biological probes, aptamer (Ap) and antibody (Ab), were used to specifically recognize AFB1, and a large number of ferrocene polymers were grafted on the electrode surface by eRAFT polymerization, which greatly improved the specificity and sensitivity of the sensor. The detection limit of AFB1 was 37.34 fg/mL. In addition, the recovery rate was 95.69% to 107.65% and the RSD was 0.84% to 4.92% by detecting 9 spiked samples. The delighted reliability of this method was verified by HPLC-FL.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Polímeros , Reprodutibilidade dos Testes , Técnicas Biossensoriais/métodos , Técnicas Eletroquímicas/métodos , Aflatoxina B1/análise , Limite de Detecção
12.
Talanta ; 257: 124360, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-36801566

RESUMO

Plant diseases caused by tobacco mosaic viruses (TMV) reduce the yield and quality of crops and cause significant losses. Early detection and prevention of TMV has important value of research and reality. Herein, a fluorescent biosensor was constructed for highly sensitive detection of TMV RNA (tRNA) based on the principle of base complementary pairing, polysaccharides and atom transfer radical polymerization by electron transfer activated regeneration catalysts (ARGET ATRP) as double signal amplification strategy. The 5'-end sulfhydrylated hairpin capture probe (hDNA) was first immobilized on amino magnetic beads (MBs) by a cross-linking agent, which specifically recognizes tRNA. Then, chitosan binds to BIBB, providing numerous active sites for fluorescent monomer polymerization, which successfully significantly amplifying the fluorescent signal. Under optimal experimental conditions, the proposed fluorescent biosensor for the detection of tRNA has a wide detection range from 0.1 pM to 10 nM (R2 = 0.998) with a limit of detection (LOD) as low as 1.14 fM. In addition, the fluorescent biosensor showed satisfactory applicability for the qualitative and quantitative analysis of tRNA in real samples, thereby demonstrating the potential in the field of viral RNA detection.


Assuntos
Técnicas Biossensoriais , Vírus do Mosaico do Tabaco , RNA , Polissacarídeos , Limite de Detecção
13.
Bioelectrochemistry ; 151: 108402, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36841148

RESUMO

Cardiac troponin I (cTnI) is considered as the gold standard for the diagnosis of acute myocardial infarction (AMI) because of its excellent specificity and sensitivity. Herein, a novel aptasensor based on the dual signal amplification strategy of Polyethyleneimine functionalized Graphene oxide (GO) and ring-opening polymerization (ROP) for the first time was successfully constructed to achieve high sensitivity detection of cTnI. Briefly, cTnI-aptamer 1 (Apt1) was immobilized on the surface of gold electrode by self-assembly of Au-S bonds to specifically capture cTnI. After specific recognition of cTnI, Apt2 coated PEI-functionalized GO composites acted as macroinitiators for the subsequent ROP reaction. Next, α-amino acid-N-carboxylic acid anhydride ferrocene derivatives (NCA-Fc), the monomer for ROP reaction, was added to the electrode surface. The combined application of PEI-functionalized GO and NCA-Fc better achieves the high sensitivity and signal amplification of the aptasensor. Under optimal conditions, the aptasensor exhibited a wide linear range of 10 fg mL-1 to 10 ng mL-1 and the limit of detection was 3.78 fg mL-1. Moreover, this method displayed the advantages of good selectivity, simple operation and excellent stability. Meanwhile, the aptasensor had good accuracy and applicability even in real serum samples analysis, demonstrating its considerable application potential in biomedical assays.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Grafite , Nanopartículas Metálicas , Limite de Detecção , Troponina I/análise , Polimerização , Aptâmeros de Nucleotídeos/química , Grafite/química , Técnicas Eletroquímicas/métodos , Técnicas Biossensoriais/métodos , Nanopartículas Metálicas/química
14.
Talanta ; 252: 123775, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36037766

RESUMO

Alkaline phosphatase (ALP) is a significant hydrolase enzyme found in living organisms, and the dysregulation of its physiological activity has been correlated with a variety of diseases. Exploring the activity of ALP has important implications for biomedical research and clinical diagnosis. Accordingly, we have developed a novel, highly sensitive electrochemical biosensor for the analysis of ALP. Based on photoinduced atom transfer radical polymerisation (photoATRP), this strategy combined a fabricated biosensor with hydrolysate produced by the hydrolysis of O-phosphoethanolamine by ALP. Furthermore, for signal amplification, photoATRP synthesises uses polymers with plentiful binding sites for ferrocenylmethyl methacrylate, and by using a photoredox catalyst under blue light irradiation to perform this without the need for copper complexes, it is beneficial for environmental protection compared to traditional atom transfer radical polymerisation (ATRP). The biosensor had a linear range of 10-150 mU·mL-1, with R2 = 0.998, and detection limits as low as 2.12 mU·mL-1. Moreover, by exhibiting outstanding selectivity and interference resistance in human serum samples, this sensor has great potential for practical applications.


Assuntos
Fosfatase Alcalina , Técnicas Biossensoriais , Humanos , Polimerização , Bioensaio , Catálise , Limite de Detecção , Técnicas Eletroquímicas
15.
Anal Biochem ; 660: 114971, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36328214

RESUMO

Exosome is an emerging tumor marker, whose concentration level can reflect the occurrence and development of tumors. The development of rapid and sensitive exosome detection platform is of great significance for early warning of cancer occurrence. Here, a strategy for electrochemical detection of A549-cell-derived exosomes was established based on DNA/ferrocene-modified single-walled carbon nanotube complex (DNA/SWCNT-Fc). DNA/SWCNT-Fc complexes function as a signal amplification platform to promote electron transfer between electrochemical signal molecules and electrodes, thereby improving sensitivity. At the same time, the exosomes can be attached to DNA/SWCNT-Fc nanocomposites via the established PO43--Ti4+-PO43- method. Moreover, the application of EGFR antibody, which can specifically capture A549 exosomes, could improve the accuracy of this sensing system. Under optimal experimental conditions, the biosensor showed good linear relationship between the peak current and the logarithm of exosomes concentration from 4.66 × 106 to 9.32 × 109 exosomes/mL with a detection limit of 9.38 × 104 exosomes/mL. Furthermore, this strategy provides high selectivity for exosomes of different cancer cells, which can be applied to the detection of exosomes in serum samples. Thus, owing to its advantages of high sensitivity and good selectivity, this method provides a diversified platform for exosomes identification and has great potential in early diagnosis and biomedical applications.


Assuntos
Exossomos , Nanotubos de Carbono , Metalocenos , DNA
16.
Anal Bioanal Chem ; 414(23): 6955-6964, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35972525

RESUMO

Alkaline phosphatase (ALP), an important hydrolase involved in dephosphorylation, is a common clinical indicator of many diseases. In the present study, we constructed a novel electrochemical sensor using amifostine as the substrate of ALP and activators regenerated by electron transfer atom transfer radical polymerization (ARGET ATRP) as a signal amplification strategy for sensitive determination of ALP activity. In particular, in the presence of ALP, the phosphate group of amifostine was hydrolyzed to form a sulfhydryl group, which could attach to a gold electrode via a sulfur-gold bond. Then, the initiator α-bromophenylacetic acid (BPAA) was linked to the hydrolysis product of amifostine through an amide bond, resulting in the production of electroactive polymer chains on the gold electrode by the monomer ferrocenylmethyl methacrylate (FMMA) via ARGET ATRP. Under optimal parameters, the electrochemical sensor demonstrated a limit of detection (LOD) of 1.71 mU mL-1 with a linear range of 5-100 mU mL-1. In addition to satisfactory selectivity, the potential application of this approach for ALP activity detection in human serum samples was demonstrated. Due to its efficiency, simplicity of operation, and cost-effectiveness, the proposed electrochemical sensor has great promise as a universal method for ALP assays and inhibitor screening.


Assuntos
Amifostina , Técnicas Biossensoriais , Fosfatase Alcalina , Técnicas Biossensoriais/métodos , DNA/química , Técnicas Eletroquímicas/métodos , Ouro/química , Humanos , Limite de Detecção
17.
Anal Biochem ; 655: 114834, 2022 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-35940299

RESUMO

Herein, an electroluminescence (ECL) biosensor was constructed by combining click chemistry with activators regenerated by electron transfer-atom transfer radical polymerization (ARGET-ATRP) to sensitively assay tobacco mosaic virus (TMV) RNA for the first time. First, hairpin DNA (hDNA) was self-assembled on the gold electrode surface through Au-S bonding. The hDNA hybridized with the tDNA to form tRNA/hDNA hybrids in the presence of TMV RNA (tRNA), so that the azide group labelled at the end of the hDNA was kept away from the electrode surface. Subsequently, the initiator for the ARGET-ATRP reaction was modified on the electrode surface by chemical bonds via click chemistry. Then, N-acryloxysuccinimide (NAS)-labelled polymer chains were successfully formed on the electrode surface by ARGET-ATRP. Under the optimized conditions, a good linear relationship existed with the ECL signal and the logarithm of tRNA concentration in the range of 0.1 pM-10 nM, and the limit of detection was 2.61 fM. In addition, this strategy can identify mismatched bases and performs well in recovery assays in real samples. For its high sensitivity, selectivity, simplicity and economy, the ECL biosensor shows great potential for practical applications.


Assuntos
Técnicas Biossensoriais , Vírus do Mosaico do Tabaco , Química Click , Polimerização , RNA , Vírus do Mosaico do Tabaco/genética
18.
Spectrochim Acta A Mol Biomol Spectrosc ; 280: 121535, 2022 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-35752041

RESUMO

In this work, a novel fluorescent biosensor for sensitive detecting of aflatoxin B1 (AFB1) was constructed through activators regenerated by electron transfer for atom transfer radical polymerization (ARGET-ATRP) for the first time. The AFB1 antigen was immobilized on the carboxy magnetic beads (MBs) by forming a sandwich-type "aptamer-antigen-antibody" immune system. Then, acrylamid (AM) was introduced through ARGET-ATRP to provide binding sites for the signaling molecules. Finally, carboxy porphyrins (TPP*) were connected with monomers through an amide bond and fixed on the MBs. Under the optimal experimental conditions, the fluorescence intensity and the logarithm of the concentration of AFB1 showed a good relationship from 100 fg mL-1 to 100 ng mL-1, with the limit of detection (LOD) as low as 8.38 fg mL-1. In addition, the method shows good selectivity and excellent reproducibility. More importantly, the biosensor has applied to the quantitative analysis of AFB1 in four Chinese medicines, and this strategy could potentially serve as a novel means for sensitive detecting of AFB1 in complex matrices.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Porfirinas , Aflatoxina B1/análise , Aptâmeros de Nucleotídeos/química , Técnicas Biossensoriais/métodos , Limite de Detecção , Polimerização , Reprodutibilidade dos Testes
19.
Anal Chim Acta ; 1219: 340032, 2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-35715132

RESUMO

Cardiac troponin I (cTnI) is considered to be the most valuable biomarker for the diagnosis of acute myocardial infarction (AMI). The sensitive and efficient determination of cTnI is essential for the early diagnosis and prognostic assessment of AMI. In this paper, we designed for the first time an electrochemical immunosensor based on the ring-opening polymerization (ROP) reaction as a signal amplification strategy for the highly sensitive detection of cTnI. Briefly, 3-mercaptopropionic acid (MPA) was used as a cross-linking agent to immobilize Ab1 on the surface of gold electrodes, and subsequently Ab1 specifically captured cTnI. Then, the glycolic acid-coupled cTnI-secondary antibody (GA-Ab2) bound specifically to cTnI to form a sandwich structure and provided the initiation site for the subsequent polymerization reaction. Subsequently, ferrocene formyloxyate propylene oxide (FFAPO) was used as the monomer and large quantities of electroactive polymers were grafted to the electrode surface via a hydroxyl-initiated ROP reaction, which significantly amplified the electrochemical signal. Under optimal conditions, the immunosensor displayed good linearity in the concentration range of 1 pg mL-1-1 µg mL-1 and the limit of detection down to 57.14 fg mL-1, which was superior to most of those reported assays. Compared to other signal amplification strategies, this ROP reaction showed relatively easy access to raw materials and comparatively mild reaction conditions. In addition, the results of the serum sample detection capability indicated that the immunosensor exhibited excellent detection selectivity and reliability in serum. Thus, owing to its good selectivity, high sensitivity and excellent stability, the immunosensor shows great potential for clinical application.


Assuntos
Técnicas Biossensoriais , Nanopartículas Metálicas , Anticorpos Imobilizados , Técnicas Biossensoriais/métodos , Técnicas Eletroquímicas/métodos , Ouro/química , Imunoensaio/métodos , Limite de Detecção , Nanopartículas Metálicas/química , Polimerização , Reprodutibilidade dos Testes , Troponina I
20.
Bioelectrochemistry ; 144: 108037, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34906819

RESUMO

Herein, an electrochemical biosensor for detecting tobacco mosaic virus (TMV) RNA is constructed by activator regenerated by electron transfer atom transfer radical polymerization (ARGET ATRP) combined with duplex-specific nuclease (DSN)-assisted target recycling. First, the captured DNA (cDNA) is self-assembled on the electrode surface and hybridizes with the TMV RNA (tRNA) to form cDNA/tRNA hybrids. And then the initiator of ARGET ATRP (α-bromoisobutyric acid, BMP) is attached to the cDNA via an amide bond and later triggers ARGET ATRP. Many electroactive monomers (ferrocenylmethyl methacrylate, FMMA) are polymerized and a remarkable electrical signal response of ferrocene (Fc) is obtained. However, with the present of DSN, DSN cleaves the cDNA/tRNA hybrid and releases tRNA to hybridize with another cDNA, thereby causing significant shortening of the length of the cDNA. The number of polymer chains on the electrode surface is drastically reduced, which is followed by a noticeable reduction in the signal of Fc. The method shows high sensitivity, superior selectivity, excellent stability and good reproducibility under optimal conditions with the limit of detection (LOD) of 2.9 fM. Furthermore, the biosensor showed satisfactory applicability in detecting tRNA in real samples, thereby demonstrating the potential of the method for practical TMV RNA detection.


Assuntos
Vírus do Mosaico do Tabaco
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