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1.
Food Sci Biotechnol ; 33(13): 2971-2978, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39220306

RESUMEN

In this study, xylitol, a common sweetener and sucrose substitute in low-calorie foods, was quantified by high-performance liquid chromatography (HPLC). During the establishment of the analytical method, three representative detection approaches, ultraviolet detector (UVD), evaporative light scattering detector, and refractive index detector, were compared and applied to determine the xylitol content in various foods distributed in Korea. The results were compared for method validation, measurement uncertainty, and applicability. As a result, HPLC-UVD showed the lowest limit of detection (0.01 mg/L) and limit of quantification (0.04 mg/L) among the three methods. It showed a low range of relative expanded uncertainty (1.12-3.98%) and could quantify xylitol in the wide range of the samples, even trace amounts of xylitol. Therefore, a total of 160 food items, including chewing gum, candy, beverage, tea, other processed products, and beverage base, were applied with three replicates by the proposed HPLC-UVD method.

2.
Food Sci Biotechnol ; 33(12): 2747-2754, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39184988

RESUMEN

This study reports the improvement and validation of a colorimetric method to quantify polysorbates (20, 60, 65, and 80) in food by measuring absorbance at 620 nm using ultraviolet-visible spectrophotometry. The method was validated for linearity, limit of detection (LOD), limit of quantitation (LOQ), precision, accuracy, and measurement uncertainty. The coefficient of determination was linear (r 2 ≥ 0.9991) over the measured concentration range of 50-1000 mg/L. The LOD and LOQ were 2.3-4.9 and 7.0-15.0 mg/kg, respectively. Intra-day and inter-day accuracy and precision were 91.9-104.1% and 0.1-1.1% RSD, and 91.6-103.8% and 0.4-5.0% RSD, respectively. The result of inter-laboratory recovery was 90.9-99.8% and the measurement uncertainty was < 16% with the compliance of the CODEX recommendation. Sauce, bread, whipped cream, rice cake, ice cream, and various other polysorbate-labeled food products (n = 229, detection range; N.D.-16,442.3 mg/kg) distributed in Korea were analyzed to confirm the applicability of the analytical method. Supplementary Information: The online version contains supplementary material available at 10.1007/s10068-024-01544-w.

5.
Am J Transl Res ; 15(10): 6299-6303, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37969182

RESUMEN

Facet joint synovial cysts can cause significant back pain and radiculopathy. Treatment options for symptomatic facet joint synovial cysts include surgical excision, facet joint steroid injections, and cyst aspiration. Herein, we report our experience of successfully rupturing a lumbar facet joint synovial cyst through a percutaneous approach with two needles using forceful pressure under C-arm fluoroscopic guidance. The patient experienced immediate symptom improvement that persisted throughout the 24-month follow-up. Our experience highlights that the volume effect technique is a valuable treatment option for symptomatic facet joint synovial cysts under fluoroscopic guidance.

7.
Am J Transl Res ; 14(8): 5754-5759, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36105055

RESUMEN

Remimazolam is a new intravenously administered ultra-short-acting benzodiazepine used in anesthesia or sedation. Remimazolam offers several advantages over other short-acting sedatives, including an organ-independent metabolism and rapid and predictable onset and recovery. Furthermore, remimazolam shows less cardiovascular-inhibitory effects than other anesthetics. Atrial flutter is a form of cardiac arrhythmia that is associated with serious health-related outcomes and a substantial economic burden. Acute onset of atrial flutter can cause cardiac dysfunction, hypotension, and myocardial ischemia. Moreover, patients with atrial flutter are likely to have an increased risk of both atrial fibrillation and stroke. In this case report, a patient with a 1-year history of atrial flutter underwent general anesthesia for robot-assisted laparoscopic prostatectomy. Using continuous remimazolam infusion, anesthesia and surgery were successfully completed without sudden changes in the patient's blood pressure, heart rate, or electrocardiogram. This case report describes the first reported use of remimazolam to induce general anesthesia in a patient with atrial flutter. The findings suggest that remimazolam can reduce the hemodynamic risk during anesthesia in patients with arrhythmias such as atrial flutter, and is a suitable option for anesthesia in patients with arrhythmias.

8.
Am J Respir Cell Mol Biol ; 67(3): 309-319, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35679109

RESUMEN

Pulmonary fibrosis is a devastating lung disease with few therapeutic options. CHIT1 (chitinase 1), an 18 glycosyl hydrolase family member, contributes to the pathogenesis of pulmonary fibrosis through the regulation of TGF-ß (transforming growth factor-ß) signaling and effector function. Therefore, CHIT1 is a potential therapeutic target for pulmonary fibrosis. This study aimed to identify and characterize a druggable CHIT1 inhibitor with strong antifibrotic activity and minimal toxicity for therapeutic application to pulmonary fibrosis. Extensive screening of small molecule libraries identified the aminoglycoside antibiotic kasugamycin (KSM) as a potent CHIT1 inhibitor. Elevated concentrations of CHIT1 were detected in the lungs of patients with pulmonary fibrosis. In in vivo bleomycin- and TGF-ß-stimulated murine models of pulmonary fibrosis, KSM showed impressive antifibrotic effects in both preventive and therapeutic conditions. In vitro studies also demonstrated that KSM inhibits fibrotic macrophage activation, fibroblast proliferation, and myofibroblast transformation. Null mutation of TGFBRAP1 (TGF-ß-associated protein 1), a recently identified CHIT1 interacting signaling molecule, phenocopied antifibrotic effects of KSM in in vivo lungs and in vitro fibroblasts responses. KSM inhibits the physical association between CHIT1 and TGFBRAP1, suggesting that the antifibrotic effect of KSM is mediated through regulation of TGFBRAP1, at least in part. These studies demonstrate that KSM is a novel CHIT1 inhibitor with a strong antifibrotic effect that can be further developed as an effective and safe therapeutic drug for pulmonary fibrosis.


Asunto(s)
Aminoglicósidos , Antifibróticos , Quitinasas , Fibrosis Pulmonar , Aminoglicósidos/farmacología , Aminoglicósidos/uso terapéutico , Animales , Antifibróticos/farmacología , Antifibróticos/uso terapéutico , Bleomicina/farmacología , Quitinasas/antagonistas & inhibidores , Fibroblastos/metabolismo , Humanos , Pulmón/efectos de los fármacos , Pulmón/patología , Ratones , Ratones Endogámicos C57BL , Fibrosis Pulmonar/inducido químicamente , Fibrosis Pulmonar/tratamiento farmacológico , Factor de Crecimiento Transformador beta/metabolismo
9.
Am J Transl Res ; 13(10): 11943-11947, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34786126

RESUMEN

OBJECTIVE: Anesthesia preoperative evaluation clinics (APECs) are currently operating in several South Korean hospitals. While several studies have investigated the impact of APEC operations on the length of total hospital stay (LTHS), few have investigated their impact on the length of preoperative hospital stay (LPHS) for patients. In this study, we aimed to determine whether APEC affected the LPHS and LTHS. METHODS: Data of all patients who underwent surgery at Chungbuk National University Hospital between September 2009 and August 2019 were analyzed retrospectively. All patients who had undergone laparoscopic cholecystectomy over the last 10 years were categorized into two groups: those who visited the APEC (Group A), and those who did not (Group B). The age, sex, American Society of Anesthesiologists physical status score, LPHS, and LTHS of the two groups were compared. RESULTS: The LPHS was 1.03±0.2 days in Group A and 1.61±1.6 days in Group B. The LTHS was 4.77±1.9 days in Group A and 5.63±2.6 days in Group B. The LPHS and LTHS of the two groups differed by 0.58 and 0.9 days, respectively. CONCLUSION: We evaluated the effect of APEC operations on the LPHS and LTHS of inpatients undergoing laparoscopic cholecystectomy and observed a decrease in both the LPHS and LTHS. Understanding and accepting the importance of APEC is significant for physicians and administrators working to improve hospital efficiency and patient outcomes. Further research is needed to investigate the need and benefits of APECs.

10.
Am J Transl Res ; 13(10): 12021-12025, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34786137

RESUMEN

A 57-year-old man underwent lumbar selective nerve root block (SNRB) for low back pain and lower radiating pain caused by left-sided L4 disc herniation. He presented to the emergency department with fever, headache and aggravated low back pain approximately 3 hours after the procedure. Infection was suspected; hence, blood tests, cerebrospinal fluid (CSF) tests, lumbar magnetic resonance imaging, and brain computed tomography were performed. Imaging findings were not suggestive of infection. The CSF was turbid and yellowish with pleiocytosis; however, the CSF culture was negative. Based on these findings, the patient was diagnosed with acute meningitis. Broad-spectrum antibiotics and steroid therapy were initiated considering the patient's age and general condition. From hospital day (HD) 2, fever and headache were reduced and disappeared completely by HD 5. At the last follow-up, 1 month after discharge, the patient had no symptoms. Acute meningitis is associated with a high mortality and neurologic deficits. Hence, timely tests, diagnosis, and treatment are critical for positive outcomes. Symptoms of meningitis following a nerve block generally occur within 24-48 hours after the procedure. This case is notable, as it involved a quicker and more sudden onset of symptoms; meningitis occurred only a few hours after lumbar selective nerve root block.

11.
Biomater Res ; 25(1): 35, 2021 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-34706765

RESUMEN

BACKGROUND: Critical bone defects remain challenges for clinicians, which cannot heal spontaneously and require medical intervention. Following the development of three-dimensional (3D) printing technology is widely used in bone tissue engineering for its outstanding customizability. The 3D printed scaffolds were usually accompanied with growth factors, such as bone morphometric protein 2 (BMP-2), whose effects have been widely investigated on bone regeneration. We previously fabricated and investigated the effect of a polylactic acid (PLA) cage/Biogel scaffold as a carrier of BMP-2. In this study, we furtherly investigated the effect of another shape of PLA cage/Biogel scaffold as a carrier of BMP-2 in a rat calvaria defect model and an ectopic ossification (EO) model. METHOD: The PLA scaffold was printed with a basic commercial 3D printer, and the PLA scaffold was combined with gelatin and alginate-based Biogel and BMP-2 to induce bone regeneration. The experimental groups were divided into PLA scaffold, PLA scaffold with Biogel, PLA scaffold filled with BMP-2, and PLA scaffold with Biogel and BMP-2 and were tested both in vitro and in vivo. One-way ANOVA with Bonferroni post-hoc analysis was used to determine whether statistically significant difference exists between groups. RESULT: The in vitro results showed the cage/Biogel scaffold released BMP-2 with an initial burst release and followed by a sustained slow-release pattern. The released BMP-2 maintained its osteoinductivity for at least 14 days. The in vivo results showed the cage/Biogel/BMP-2 group had the highest bone regeneration in the rat calvarial defect model and EO model. Especially, the bone regenerated more regularly in the EO model at the implanted sites, which indicated the cage/Biogel had an outstanding ability to control the shape of regenerated bone. CONCLUSION: In conclusion, the 3D printed PLA cage/Biogel scaffold system was proved to be a proper carrier for BMP-2 that induced significant bone regeneration and induced bone formation following the designed shape.

12.
Cells ; 10(2)2021 01 20.
Artículo en Inglés | MEDLINE | ID: mdl-33498326

RESUMEN

A recently discovered human glycoprotein, chitinase 3-like 1 (Chi3L1), may play a role in inflammation, tissue remodeling, and visceral fat accumulation. We hypothesize that Chi3L1 gene expression is important in the development of hepatic insulin resistance characterized by the generation of pAKT, pGSK, and pERK in wild type and Chi3L1 knockout (KO) murine liver following insulin stimulation. The Chi3L1 gene and protein expression was evaluated by Real Time PCR and ELISA; lipid accumulation in hepatocytes was also assessed. To alter Chi3L1 function, three different anti-Chi3L1 monoclonal antibodies (mAbs) were administered in vivo and effects on the insulin signaling cascade and hepatic lipid deposition were determined. Transmission of the hepatic insulin signal was substantially improved following KO of the CHi3L1 gene and there was reduced lipid deposition produced by a HFD. The HFD-fed mice exhibited increased Chi3L1 expression in the liver and there was impaired insulin signal transduction. All three anti-Chi3L1 mAbs partially restored hepatic insulin sensitivity which was associated with reduced lipid accumulation in hepatocytes as well. A KO of the Chi3L1 gene reduced lipid accumulation and improved insulin signaling. Therefore, Chi3L1 gene upregulation may be an important factor in the generation of NAFLD/NASH phenotype.


Asunto(s)
Proteína 1 Similar a Quitinasa-3/metabolismo , Resistencia a la Insulina , Hígado/metabolismo , Hígado/patología , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Animales , Anticuerpos Monoclonales/administración & dosificación , Anticuerpos Monoclonales/farmacología , Biopsia , Proteína 1 Similar a Quitinasa-3/genética , Dieta Alta en Grasa , Conducta Alimentaria , Insulina/metabolismo , Ratones Endogámicos C57BL , Ratones Noqueados , Enfermedad del Hígado Graso no Alcohólico/genética , Enfermedad del Hígado Graso no Alcohólico/patología , Transducción de Señal
13.
Life Sci Alliance ; 2(3)2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-31085559

RESUMEN

TGF-ß1 is a critical mediator of tissue fibrosis in health and disease whose effects are augmented by chitinase 1 (CHIT1). However, the mechanisms that CHIT1 uses to regulate TGF-ß1-mediated fibrotic responses have not been defined. Here, we demonstrate that CHIT1 enhances TGF-ß1-stimulated fibrotic cellular and tissue responses and TGF-ß1 signaling. Importantly, we also demonstrate that these effects are mediated by the ability of CHIT1 to inhibit TGF-ß1 induction of its feedback inhibitor, SMAD7. CHIT1 also interacted with TGF-ß receptor associated protein 1 (TGFBRAP1) and forkhead box O3 (FOXO3) with TGFBRAP1 playing a critical role in CHIT1 enhancement of TGF-ß1 signaling and effector responses and FOXO3 playing a critical role in TGF-ß1 induction of SMAD7. These pathways were disease relevant because the levels of CHIT1 were increased and inversely correlated with SMAD7 in tissues from patients with idiopathic pulmonary fibrosis or scleroderma-associated interstitial lung disease. These studies demonstrate that CHIT1 regulates TGF-ß1/SMAD7 axis via TGFBRAP1 and FOXO3 and highlight the importance of these pathways in the pathogenesis of pulmonary fibrosis.


Asunto(s)
Proteína Forkhead Box O3/metabolismo , Hexosaminidasas/genética , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Fibrosis Pulmonar/etiología , Fibrosis Pulmonar/metabolismo , Proteína smad7/metabolismo , Factor de Crecimiento Transformador beta/metabolismo , Fibroblastos/metabolismo , Regulación de la Expresión Génica , Genes Reporteros , Hexosaminidasas/metabolismo , Humanos , Inmunohistoquímica , Regiones Promotoras Genéticas , Fibrosis Pulmonar/patología , ARN Interferente Pequeño/genética , Transducción de Señal
14.
JCI Insight ; 3(18)2018 09 20.
Artículo en Inglés | MEDLINE | ID: mdl-30232270

RESUMEN

The pathogenetic mechanisms underlying the pathologic fibrosis in diseases such as idiopathic pulmonary fibrosis (IPF) are poorly understood. To identify genetic factors affecting susceptibility to IPF, we analyzed a murine genetic model of IPF in which a profibrotic cytokine (TGF-ß1) was expressed in the lungs of 10 different inbred mouse strains. Surprisingly, the extent of TGF-ß1-induced lung fibrosis was highly strain dependent. Haplotype-based computational genetic analysis and gene expression profiling of lung tissue obtained from fibrosis-susceptible and -resistant strains identified laminin α1 (Lama1) as a genetic modifier for susceptibility to IPF. Subsequent studies demonstrated that Lama1 plays an important role in multiple processes that affect the pulmonary response to lung injury and susceptibility to fibrosis, which include: macrophage activation, fibroblast proliferation, myofibroblast transformation, and the production of extracellular matrix. Also, Lama1 mRNA expression was significantly increased in lung tissue obtained from IPF patients. These studies identify Lama1 as the genetic modifier of TGF-ß1 effector responses that significantly affects the development of pulmonary fibrosis.


Asunto(s)
Fibrosis Pulmonar Idiopática/genética , Fibrosis Pulmonar Idiopática/metabolismo , Laminina/genética , Laminina/metabolismo , Factor de Crecimiento Transformador beta1/metabolismo , Animales , Proliferación Celular , Proteínas de la Matriz Extracelular/metabolismo , Perfilación de la Expresión Génica , Regulación de la Expresión Génica , Humanos , Fibrosis Pulmonar Idiopática/patología , Pulmón/patología , Lesión Pulmonar , Activación de Macrófagos , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos , Proteínas Proto-Oncogénicas c-akt/metabolismo , Transducción de Señal , Proteína Smad2/metabolismo
16.
Nat Commun ; 7: 12752, 2016 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-27629921

RESUMEN

Recent studies demonstrated that chitinase 3-like-1 (Chi3l1) binds to and signals via IL-13Rα2. However, the mechanism that IL-13Rα2 uses to mediate the effects of Chi3l1 has not been defined. Here, we demonstrate that the membrane protein, TMEM219, is a binding partner of IL-13Rα2 using yeast two-hybrid, co-immunoprecipitation, co-localization and bimolecular fluorescence complementation assays. Furthermore, fluorescence anisotropy nanodisc assays revealed a direct physical interaction between TMEM219 and IL-13Rα2-Chi3l1 complexes. Null mutations or siRNA silencing of TMEM219 or IL-13Rα2 similarly decreased Chi3l1-stimulated epithelial cell HB-EGF production and macrophage MAPK/Erk and PKB/Akt activation. Null mutations of TMEM219 or IL-13Rα2 also phenocopied one another as regards the ability of Chi3l1 to inhibit oxidant-induced apoptosis and lung injury, promote melanoma metastasis and stimulate TGF-ß1. TMEM219 also contributed to the decoy function of IL-13Rα2. These studies demonstrate that TMEM219 plays a critical role in Chi3l1-induced IL-13Rα2 mediated signalling and tissue responses.


Asunto(s)
Proteína 1 Similar a Quitinasa-3/metabolismo , Subunidad alfa2 del Receptor de Interleucina-13/metabolismo , Proteínas de la Membrana/metabolismo , Animales , Apoptosis , Línea Celular Tumoral , Factor de Crecimiento Similar a EGF de Unión a Heparina/metabolismo , Humanos , Lesión Pulmonar/metabolismo , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/secundario , Sistema de Señalización de MAP Quinasas , Melanoma Experimental/metabolismo , Melanoma Experimental/patología , Ratones Endogámicos C57BL , Metástasis de la Neoplasia , Proteínas Proto-Oncogénicas c-akt/metabolismo , Factor de Crecimiento Transformador beta1/metabolismo , Técnicas del Sistema de Dos Híbridos , Vía de Señalización Wnt
17.
ACS Nano ; 10(8): 7287-96, 2016 08 23.
Artículo en Inglés | MEDLINE | ID: mdl-27327579

RESUMEN

For several decades, significant efforts have been made in developing artificial taste sensors to recognize the five basic tastes. So far, the well-established taste sensor is an E-tongue, which is constructed with polymer and lipid membranes. However, the previous artificial taste sensors have limitations in various food, beverage, and cosmetic industries because of their failure to mimic human taste reception. There are many interactions between tastants. Therefore, detecting the interactions in a multiplexing system is required. Herein, we developed a duplex bioelectronic tongue (DBT) based on graphene field-effect transistors that were functionalized with heterodimeric human umami taste and sweet taste receptor nanovesicles. Two types of nanovesicles, which have human T1R1/T1R3 for the umami taste and human T1R2/T1R3 for the sweet taste on their membranes, immobilized on micropatterned graphene surfaces were used for the simultaneous detection of the umami and sweet tastants. The DBT platform led to highly sensitive and selective recognition of target tastants at low concentrations (ca. 100 nM). Moreover, our DBT was able to detect the enhancing effect of taste enhancers as in a human taste sensory system. This technique can be a useful tool for the detection of tastes instead of sensory evaluation and development of new artificial tastants in the food and beverage industry.


Asunto(s)
Órganos Artificiales , Receptores Acoplados a Proteínas G , Gusto , Lengua , Humanos , Nanopartículas , Papilas Gustativas
18.
J Biol Chem ; 291(12): 6433-46, 2016 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-26817844

RESUMEN

The siRNA silencing approach has long been used as a method to regulate the expression of specific target genes in vitro and in vivo. However, the effectiveness of delivery and the nonspecific immune-stimulatory function of siRNA are the limiting factors for therapeutic applications of siRNAs. To overcome these limitations, we developed self-assembled micelle inhibitory RNA (SAMiRNA) nanoparticles made of individually biconjugated siRNAs with a hydrophilic polymer and lipid on their ends and characterized their stability, immune-stimulatory function, and in vivo silencing efficacy. SAMiRNAs form very stable nanoparticles with no significant degradation in size distribution and polydispersity index over 1 year. Overnight incubation of SAMiRNAs (3 µm) on murine peripheral blood mononuclear cells did not cause any significant elaboration of innate immune cytokines such as TNF-α, IL-12, or IL-6, whereas unmodified siRNAs or liposomes or liposome complexes significantly stimulated the expression of these cytokines. Last, the in vivo silencing efficacy of SAMiRNAs was evaluated by targeting amphiregulin and connective tissue growth factor in bleomycin or TGF-ß transgenic animal models of pulmonary fibrosis. Intratracheal or intravenous delivery two or three times of amphiregulin or connective tissue growth factor SAMiRNAs significantly reduced the bleomycin- or TGF-ß-stimulated collagen accumulation in the lung and substantially restored the lung function of TGF-ß transgenic mice. This study demonstrates that SAMiRNA nanoparticle is a less toxic, stable siRNA silencing platform for efficient in vivo targeting of genes implicated in the pathogenesis of pulmonary fibrosis.


Asunto(s)
Terapia Genética , Fibrosis Pulmonar/terapia , Interferencia de ARN , ARN Interferente Pequeño/genética , Anfirregulina , Animales , Células Cultivadas , Colágeno/metabolismo , Factor de Crecimiento del Tejido Conjuntivo/genética , Factor de Crecimiento del Tejido Conjuntivo/metabolismo , Familia de Proteínas EGF/genética , Familia de Proteínas EGF/metabolismo , Femenino , Técnicas de Silenciamiento del Gen/métodos , Pulmón/metabolismo , Pulmón/patología , Masculino , Ratones Endogámicos C57BL , Micelas , Nanopartículas , Fibrosis Pulmonar/genética , ARN Interferente Pequeño/administración & dosificación , ARN Interferente Pequeño/farmacocinética , Distribución Tisular
19.
J Mater Chem B ; 4(29): 5025-5034, 2016 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-32264029

RESUMEN

17ß-Estradiol is known as a steroid hormone in the human body but it is also known as a disruptor that can cause disequilibrium and dysfunction of the human immune system. Recently, there has been much interest in developing biosensors to detect low concentrations of 17ß-estradiol. In this work, size-controllable aptamer conjugated ultrathin carboxylated polypyrrole nanotubes (A-UCPPyNTs) were fabricated as transducers in 17ß-estradiol field-effect transistor (FET)-type biosensors. They were manufactured via a self-degradation method under several different conditions to control the diameter of the nanotubes. For targeting 17ß-estradiol, the binding aptamers were immobilized through covalent bonding on its surface. The resulting A-UCPNT FET-type biosensor demonstrated p-type behavior with outstanding electrical conductivity, and exhibited Ohmic contacts between the samples and electrodes. The smaller diameter (40 nm) of ultrathin carboxylated polypyrrole nanotubes (UCPPyNTs) contributed to the biosensor's enhanced performance by generating a larger surface area, thereby increasing the number of conjugated binding aptamers. In conclusion, the A-UCPPyNT FET-type biosensor showed extremely high sensitivity (∼1 fM) toward 17ß-estradiol, approximately 103 times more sensitive than the results found in other reports. Moreover, the A-UCPPyNT FET-type biosensor showed unique selectivity to the 17ß-estradiol molecule, in addition to outstanding reusability and long-term storage stability (4 weeks of duration achieved in this work). These performances concerned with reusability and stability were achieved by the formation of covalent bonding in the anchorage to the substrate electrode. Thus this study can be effectively applied in biological and environmental fields.

20.
Nano Lett ; 15(10): 6559-67, 2015 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-26322968

RESUMEN

Human sensory-mimicking systems, such as electronic brains, tongues, skin, and ears, have been promoted for use in improving social welfare. However, no significant achievements have been made in mimicking the human nose due to the complexity of olfactory sensory neurons. Combinational coding of human olfactory receptors (hORs) is essential for odorant discrimination in mixtures, and the development of hOR-combined multiplexed systems has progressed slowly. Here, we report the first demonstration of an artificial multiplexed superbioelectronic nose (MSB-nose) that mimics the human olfactory sensory system, leading to high-performance odorant discriminatory ability in mixtures. Specifically, portable MSB-noses were constructed using highly uniform graphene micropatterns (GMs) that were conjugated with two different hORs, which were employed as transducers in a liquid-ion gated field-effect transistor (FET). Field-induced signals from the MSB-nose were monitored and provided high sensitivity and selectivity toward target odorants (minimum detectable level: 0.1 fM). More importantly, the potential of the MSB-nose as a tool to encode hOR combinations was demonstrated using principal component analysis.


Asunto(s)
Nariz Electrónica , Olfato , Humanos , Límite de Detección , Neuronas Receptoras Olfatorias/fisiología
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