RESUMEN
To avoid false-positive results in immunoassays due to cross-reactivity of antibodies with structural analogues, especially metabolites of target compounds, the preparation of highly specific antibodies is crucial. Preserving the characteristic structure of a target compound when designing a hapten is important when preparing highly specific antibodies. Here, we designed a novel hapten, 4-(((1,5-dimethyl-3-oxo-2-phenyl-2,3-dihydro-1H-pyrazol-4yl)amino)methyl)benzoic acid, named AA-BA, to improve the specificity of antibodies for detection of 4-methylaminoantipyrine (MAA), a residual marker of dipyrone, an important antipyretic-analgesic and anti-inflammatory drug. The structural features of the hapten remained almost the same as those of MAA. After experimental validation, monoclonal antibody 6A4 (mAb 6A4) was prepared with the half maximal inhibitory concentration (IC50) value of 4.03 ng/mL and negligible cross-reactivity with dipyrone metabolites and other antibiotics. In addition, a specific lateral flow immunoassay (LFA) strip based on colloidal gold was developed for screening MAA with a cutoff value of 25 ng/mL in milk. The developed LFA is a useful tool for rapid and accurate detection of MAA.
Asunto(s)
Anticuerpos Monoclonales , Dipirona , Dipirona/farmacología , Inmunoensayo/métodos , Haptenos , Oro Coloide/química , Límite de DetecciónRESUMEN
To meet high-throughput screening of the residues of sulfonamides (SAs) with high sensitivity toward sulfamethazine (SM2) in milk samples, a new highly sensitive lateral flow immunoassay (LFA) based on amorphous carbon nanoparticles (ACNs) was developed. First, a group-specific monoclonal antibody 10H7 (mAb 10H7) that could recognize 25 SAs with high sensitivity toward SM2 (IC50 value of 0.18 ng/mL) was prepared based on H1 as an immune hapten and H4 as a heterologous coating hapten. Then, mAb 10H7 was conjugated to ACNs as an immune probe for LFA development. Under the optimized conditions, the LFA could detect 25 SAs with the cut-off value toward SM2 of 2 ng/mL, which could meet the requirement for detection of SAs. In addition, the LFA developed was also used for screening SAs' residues in real milk samples, with results being consistent with HPLC-MS/MS. Thus, this LFA can be used as a high-throughput screening tool for detection of SAs.
Asunto(s)
Anticuerpos Monoclonales , Nanopartículas , Animales , Leche/química , Sulfonamidas/análisis , Espectrometría de Masas en Tándem , Inmunoensayo/métodos , Sulfanilamida/análisis , Haptenos , CarbonoRESUMEN
TiO2 is a promising anode material for lithium-ion batteries (LIBs) due to its low cost, suitable operating voltage, and excellent structural stability. The inherent poor electron conductivity and low ion diffusion coefficient, however, severely limit its application in lithium storage. Here, Co-doped TiO2 is synthesized by a hydrothermal method as an anode material since Co@TiO2 possesses a large specific surface area and high electronic conductivity. Thanks to the Co dopants, the ion diffusion and electron transport are both greatly improved, which is very beneficial for cycle stability, coulombic efficiency (CE), reversible capacity, and rate performance. As a result, Co@TiO2 shows a high reversible capacity of 227 mAh g-1 at 3 C, excellent rate performance, and cycling stability with a capacity of about 125 mAh g-1 at 10C after 600 cycles (1 C = 170 mA g-1).
RESUMEN
Production of high-affinity and specific antibodies to small molecules with molecular weight (MW) lower than 200 Da is challenging. Here, we designed a novel hapten, named hapten H6, for the detection of 3-methyl-quinoxaline-2-carboxylic acid (MQCA, MW of 189 Da), a residual marker of olaquindox, one of important veterinary antibiotics. The hapten H6 maintained all structural features of MQCA, especially in mulliken atomic charge distribution. Then, a monoclonal antibody (mAb) named 8C9 was obtained with an IC50 value of 0.2 µg/L, yielding a 15.5- to 88.5-fold improvement compared to previously prepared specific antibodies against MQCA. In addition, mAb 8C9 exhibited ignorable cross-reactivity with other structural analogs. Finally, a highly sensitive and specific indirect competitive ELISA based on mAb 8C9 was developed for the detection of MQCA in swine muscle and liver samples with limit of detection values of 0.04 µg/kg and 0.09 µg/kg, respectively.
Asunto(s)
Anticuerpos Monoclonales , Hígado , Animales , Porcinos , Anticuerpos Monoclonales/análisis , Inmunoensayo , Hígado/química , Músculos/química , Haptenos , Ensayo de Inmunoadsorción EnzimáticaRESUMEN
Background: Rearrangements of the anaplastic lymphoma kinase (ALK) gene comprise a small subset of non-small cell lung cancer (NSCLC). Patients with NSCLC harboring ALK fusion proteins are sensitive to ALK tyrosine kinase inhibitors (TKIs). Various fusion partners of ALK are being discovered with the application of next-generation sequencing (NGS). Case presentation: Here, we report a female patient with metastatic lung adenocarcinoma harboring LMO7-ALK (L15, A20) rearrangement revealed by NGS. The patient received crizotinib as first-line treatment and has achieved partial response with a progression-free survival over 1 year. Conclusions: We firstly found that the satisfactory response to crizotinib verified the oncogenic activity of LMO7-ALK fusion. Great progression and wide application of NGS facilitate the findings of rare fusion types.
RESUMEN
In peptide amphiphile, The positively charged amino acid arginine can inspire the ordered self-assembly of gold nanocomposites (AuNPs), transfer positive charge to AuNPs, and weaken the aggregation of AuNPs by electrostatic repulsion, whereas hydrophobic fatty acid chains regulate the self-assembly of AuNPs through hydrophobic interaction, which may be a novel strategy to overcome disordered arrangement and aggregation of AuNPs to obtain an ultra-sensitive electrochemical immunosensor for determining the total aflatoxin amount. In this study, a peptide amphiphile (C14R5), composed of five arginine residues as the hydrophilic chain and myristic acid as the hydrophobic chain, inspired AuNPs to form monodispersed hollow raspberry-like AuNPs (rasAuNPs). rasAuNPs could captured and immobilized large amounts of aflatoxin antigens via the Au-S bonds, resulting in binding to more anti-aflatoxin antibodies. In the absence of aflatoxins, the enriched antigens bound to abundant antibodies, resulting in a low blank signal current. By contrast, in the presence of aflatoxins, enough antibodies could bind to the targets and less antibodies could recognize the antigens, increasing the detection signal intensity. Under the optimal conditions, the developed sensor demonstrated a wide linear range (0.13-29.06 pg mL-1) and a low limit of detection for total aflatoxins (0.05 pg mL-1) using a mixed standard (AFB1: AFB2: AFG1: AFG2 with a weight ratio of 1:1:1:1) in peanut, peanut milk, and maize powder samples. Hence, this novel strategy improves the sensitivity of electrochemical sensors and can be easily applied to detect other small molecule compound for the purpose of food safety.
Asunto(s)
Aflatoxinas , Técnicas Biosensibles , Nanopartículas del Metal , Nanocompuestos , Aflatoxina B1/análisis , Arginina , Técnicas Biosensibles/métodos , Técnicas Electroquímicas/métodos , Oro/química , Inmunoensayo/métodos , Límite de Detección , Nanopartículas del Metal/química , Nanocompuestos/química , PéptidosRESUMEN
BACKGROUND: Identification of small pulmonary nodules is challenging in a limited intrathoracic field during minimally invasive video-assisted thoracoscopic surgery (VATS), and preoperative localization is required. Various techniques have been reported with some failure and complications. Here, we compare the feasibility and safety between electromagnetic navigation bronchoscopic marking and computed tomography (CT)-guided percutaneous marking using indocyanine green (ICG) and iopamidol. METHODS: A total of 47 patients with small-sized pulmonary nodules, scheduled to undergo video-assisted thoracoscopic limited resection, were enrolled in this study. A mixture of diluted ICG and iopamidol was injected into the lung parenchyma as a marker, using CT-guided percutaneous or electromagnetic navigation bronchoscopic injection techniques and the results were examined and compared. RESULTS: A total of 35 and 12 patients underwent preoperative marking by percutaneous injection and electromagnetic navigation bronchoscopic injection, respectively, in which a marker was detected in 33/35 (94.3%) and 12/12 (100%) patients. No combination of these procedures was performed in any patient. All markers were successfully detected in three patients who underwent injection marking at two different lesion sites. Pneumothorax occurred in five patients (14%) in the percutaneous marking group, which was relieved in all patients without the necessity for chest tube drainage. No other complication was observed in this study. CONCLUSIONS: Electromagnetic navigation bronchoscopic injection techniques using indocyanine green fluorescence plus iopamidol are safe and effective, and comparable with CT-guided localization. Furthermore, a bronchoscopic approach enables marking of multiple lesion areas without increasing patient risk, especially for puncture-related pneumothorax. KEY POINTS: SIGNIFICANT FINDINGS OF THE STUDY: Either computed tomography (CT)-guided percutaneous or electromagnetic navigation bronchoscopic injection techniques can be used for preoperative marking of pulmonary nodules with indocyanine green (ICG) fluorescence. WHAT THIS STUDY ADDS: Indocyanine green (ICG) is a safe and easily detectable fluorescent marker for video-assisted thoracoscopic surgery (VATS). A bronchoscopic injection approach enables marking of multiple lesion areas without increasing the risk of pneumothorax.