Mesoporous materials modified by aptamers and hydrophobic groups assist ultra-sensitive insulin detection in serum

2015 ◽  
Vol 51 (71) ◽  
pp. 13642-13645 ◽  
Author(s):  
Chang Lei ◽  
Chun Xu ◽  
Owen Noonan ◽  
Anand Kumar Meka ◽  
Long Zhang ◽  
...  
Keyword(s):  
Mesoporous Materials ◽  
Mesoporous Material ◽  
Limit Of Detection ◽  
Insulin Binding ◽  
Pre Treatment

A mesoporous material modified with insulin-binding-aptamers and –CH3is applied in sample pre-treatment to enhance the limit-of-detection of ELISA 30-fold.

Size Control of Block Polymer Templated Mesoporous Silicate Materials

2000 ◽  
Vol 628 ◽  
Author(s):  
Takeo Yamada ◽  
Keisuke Asai ◽  
Kenkichi Ishigure ◽  
Akira Endo ◽  
Hao S. Zhou ◽  
...  
Keyword(s):  
Mesoporous Materials ◽  
Molecular Sieve ◽  
Mesoporous Material ◽  
Triblock Copolymer ◽  
Size Control ◽  
Block Polymer ◽  
New Class ◽  
Mesoporous Silicate ◽  
Cubic Structure ◽  
Silicate Materials

ABSTRACTMesoporous materials have attracted considerable interest because of applications in molecular sieve, catalyst, and adsorbent. It will be useful for new functional device if functional molecules can be incorporated into the pore of mesoporous material. However, it is necessary to synthesize new mesoporous materials with controlled large pore size. Recently, new class of mesoporous materials has been prepared using triblock copolymer as a template. In this paper, we reported that hexagonal and cubic structure silicate mesoporous materials can be synthesized through triblock copolymer templating, and their size was controlled by synthesis condition at condensation.

Research on Detecting Tris-(2,3-dibromopropyl)-Phosphate in Textiles with the HPLC/DAD Method

2012 ◽  
Vol 441 ◽  
pp. 640-644
Author(s):  
Ke Jie Fu ◽  
Li Sheng Yang ◽  
Chang Sheng Feng ◽  
Liang Chen
Keyword(s):  
Limit Of Detection ◽  
Extraction Process ◽  
Ultrasound Assisted Extraction ◽  
Routine Testing ◽  
Assisted Extraction ◽  
Ultrasound Assisted ◽  
Pre Treatment ◽  
Finishing Agent ◽  
Detecting Method ◽  
Precision Test

A detecting method for toxic flame retardant finishing agent tris-(2,3-dibromopropyl) -phosphate (TRIS for short) in textiles was studied. In the method, an acetonitrile ultrasound-assisted extraction process was included in sample pre-treatment, and HPLC/DAD was used in the separation and identification of extractives. After that, the conditions of pre-treatment and chromatograph were optimized. The results showed that the limit of detection (LOD) by this method (S/N10) is 1.0 mg/kg, its recovery ranged from 78.1% to 98.4%, and RSD of the precision test is 3.2%, of which all met the requirements for routine testing.

Analytical and clinical validation of a novel amplicon-based NGS assay for the evaluation of circulating tumor DNA in metastatic colorectal cancer patients

2019 ◽  
Vol 57 (10) ◽  
pp. 1501-1510 ◽  
Author(s):  
Beili Wang ◽  
Shengchao Wu ◽  
Fei Huang ◽  
Minna Shen ◽  
Huiqin Jiang ◽  
...  
Keyword(s):  
Colorectal Cancer ◽  
Metastatic Colorectal Cancer ◽  
Limit Of Detection ◽  
Clinical Performance ◽  
Circulating Tumor Dna ◽  
Concordance Rate ◽  
Tissue Samples ◽  
Percent Agreement ◽  
Pre Treatment ◽  
Tumor Dna

Abstract Background Evaluating the tumor RAS/BRAF status is important for treatment selection and prognosis assessment in metastatic colorectal cancer (mCRC) patients. Correction of artifacts from library preparation and sequencing is essential for accurately analyzing circulating tumor DNA (ctDNA) mutations. Here, we assessed the analytical and clinical performance of a novel amplicon-based next-generation sequencing (NGS) assay, Firefly™, which employs a concatemer-based error correction strategy. Methods Firefly assay targeting KRAS/NRAS/BRAF/PIK3CA was evaluated using cell-free DNA (cfDNA) reference standards and cfDNA samples from 184 mCRC patients. Plasma results were compared to the mutation status determined by ARMS-based PCR from matched tissue. Samples with a mutation abundance below the limit of detection (LOD) were retested again by droplet digital polymerase chain reaction (ddPCR) or NGS. Results The Firefly assay demonstrated superior sensitivity and specificity with a 98.89% detection rate at an allele frequency (AF) of 0.2% for 20 ng cfDNA. Generally, 40.76% and 48.37% of the patients were reported to be positive by NGS of plasma cfDNA and ARMS of FFPE tissue, respectively. The concordance rate between the two platforms was 80.11%. In the pre-treatment cohort, the concordance rate between plasma and tissue was 93.33%, based on the 17 common exons that Firefly™ and ARMS genotyped, and the positive percent agreement (PPA) and negative percent agreement (NPA) for KRAS/NRAS/BRAF/PIK3CA were 100% and 99.60%, respectively. Conclusions Total plasma cfDNA detected by Firefly offers a viable complement for mutation profiling in CRC patients, given the high agreement with matched tumor samples. Together, these data demonstrate that Firefly could be routinely applied for clinical applications in mCRC patients.

A Novel Iron Silicate Mesoporous Material Synthesis and Its Characterization

2018 ◽  
Vol 24 (8) ◽  
pp. 5532-5536
Author(s):  
M. A Mary Thangam ◽  
Chellapandian Kannan
Keyword(s):  
Mesoporous Materials ◽  
Molecular Sieves ◽  
Mesoporous Material ◽  
Synthesis Method ◽  
Acid Sites ◽  
Mesoporous Molecular Sieves ◽  
Isomorphous Substitution ◽  
Main Role ◽  
Material Synthesis ◽  
Ft Ir

The mesoporous materials have variety of applications in several field particularly it has a main role in Catalysis, Petrochemical industries and Adsorption. Normally the porous material has well ordered 3Dimensional structure, huge surface area, high thermal stability and active acid sites. The properties of these materials can be varied because it is mostly depends on its template, synthesis method and isomorphous substitution of metal ions. There are two major mesoporous materials which are aluminosilicate and aluminophosphate. In this present investigation AlCl3 and FeCl3 are used in equal amount for the synthesis of mesoporous material. The synthesized material is characterized by FT-IR, XRD, TGA, BET, EDAX and TPD. Morphological images were studied by SEM. These characterization techniques confirm the formation of mesoporous molecular sieves.

Forearm insulin uptake in healthy subjects after oral glucose and intravenous glipizide

1981 ◽  
Vol 98 (3) ◽  
pp. 407-412 ◽  
Author(s):  
Arne Nygren ◽  
Lars Erik Lindblad ◽  
Lars Sundblad
Keyword(s):  
Healthy Subjects ◽  
Insulin Receptors ◽  
Random Order ◽  
Insulin Binding ◽  
Insulin Concentration ◽  
Oral Glucose ◽  
Healthy Individuals ◽  
Pre Treatment ◽  
Insulin Uptake ◽  
Arterial Insulin

Abstract. In six healthy subjects fasted overnight two different experiments were carried out on separate days and in random order: A. Oral glucose followed 60 min later by iv glipizide. B. Iv glipizide followed 60 min later by oral glucose. Each experiment was divided into two 60 min periods, and the fractionated insulin uptake by forearm tissue was calculated for each 60 min period. When the fractional insulin uptake values for these four 60 min periods were compared it was found that the uptake of insulin was significantly higher for the 60 min period that was obtained in response to glucose without glipizide pre-treatment, than it was for any of the other 60 min periods. Moreover, in some of the participants the venous insulin concentration occasionally exceeded the corresponding arterial insulin concentration after iv glipizide administration. These findings imply that glipizide may decrease insulin binding to peripheral insulin receptors in healthy individuals.

scholarly journals Aptamer-Conjugated Polydiacetylene Colorimetric Paper Chip for the Detection of Bacillus thuringiensis Spores

Sensors ◽  
2020 ◽  
Vol 20 (11) ◽  
pp. 3124
Author(s):  
Chaoge Zhou ◽  
Taeyeong You ◽  
Huisoo Jang ◽  
Hyunil Ryu ◽  
Eun-Seon Lee ◽  
...  
Keyword(s):  
Bacillus Thuringiensis ◽  
Polyvinylidene Fluoride ◽  
Color Change ◽  
Limit Of Detection ◽  
Paper Strip ◽  
High Concentration ◽  
Paper Chip ◽  
Pre Treatment ◽  
Pda Vesicles ◽  
Paper Sensor

A colorimetric polydiacetylene (PDA) paper strip sensor that can specifically recognize Bacillus thuringiensis (BT) HD-73 spores is described in this work. The target-specific aptamer was combined with PDA, and the aptamer-conjugated PDA vesicles were then coated on polyvinylidene fluoride (PVDF) paper strips by a simple solvent evaporation method. The PDA-aptamer paper strips can be used to detect the target without any pre-treatment. Using the paper strip, the presence of BT spores is directly observable by the naked eye based on the unique blue-to-red color transition of the PDA. Quantitative studies using the paper strip were also carried out by analyzing the color transitions of the PDA. The specificity of this PDA sensor was verified with a high concentration of Escherichia coli, and no discernable change was observed. The observable color change in the paper strip occurs in less than 1 h, and the limit of detection is 3 × 107 CFU/mL, much below the level harmful to humans. The PDA-based paper sensor, developed in this work, does not require a separate power or detection device, making the sensor strip highly transportable and suitable for spore analysis anytime and anywhere. Moreover, this paper sensor platform is easily fabricated, can be adapted to other targets, is highly portable, and is highly specific for the detection of BT spores.

scholarly journals New Poly(Ionic Liquid) Based Fiber for Determination of Oxytetracycline in Milk Samples by Application of SPME-CE Technique

Molecules ◽  
2019 ◽  
Vol 24 (3) ◽  
pp. 430 ◽  
Author(s):  
T. Alexandra Ferreira ◽  
J. Francisco Flores-Aguilar ◽  
Eva M. Santos ◽  
Jose A. Rodriguez ◽  
Israel S. Ibarra
Keyword(s):  
Capillary Electrophoresis ◽  
Limit Of Detection ◽  
Solid Phase ◽  
Ionic Exchange ◽  
Imidazolium Chloride ◽  
Milk Samples ◽  
Multi Stage ◽  
Pre Treatment ◽  
Poly Ionic Liquid

In this work, a procedure using solid phase microextraction in combination with capillary electrophoresis was developed for the determination of oxytetracycline in milk samples. The method involves the synthesis of poly(1-allyl-3-methyl imidazolium) chloride film on a stainless-steel bar via electropolymerization and its use as an adsorbent for oxytetracycline (OT) by an ionic exchange mechanism. The coated fiber is then immersed in milk samples for retention of oxytetracycline residues, followed by elution, drying, and reconstitution before analysis with capillary electrophoresis. The proposed method achieves a limit of detection of 70 µg L–1 with adequate precision and uncertainty, making this methodology appropriate for the determination of OT in milk samples. The method was applied to the pre-concentration and quantification of oxytetracycline in ten commercial milk samples. Two tested samples were positive for the presence of oxytetracycline but the concentration was below the maximum residue limit according to the international normative standard. The proposed methodology was evaluated according to the Eco-Scale approach, and the total score of 51 indicated that the methodology proposed is both green and acceptable despite the multi-stage character. SPME-CE methodology allows us to perform the sample pre-treatment and determination of OT in an effective and greener way, decreasing the number of steps during the analysis and the generation of waste.

Pharmacokinetics (PK) of the chimeric anti-GD2 antibody, ch14.18, in children with high-risk neuroblastoma.

2012 ◽  
Vol 30 (15_suppl) ◽  
pp. 9576-9576
Author(s):  
Ami Vijay Desai ◽  
Elizabeth Fox ◽  
Theresa C. DiSipio ◽  
L. Mary Smith ◽  
Allison Lim ◽  
...  
Keyword(s):  
Monoclonal Antibody ◽  
High Risk ◽  
Half Life ◽  
Limit Of Detection ◽  
Sampling Strategy ◽  
Volume Of Distribution ◽  
Plasma Samples ◽  
Limited Sampling ◽  
Dosing Strategies ◽  
Pre Treatment

9576 Background: The PK of ch14.18, a chimeric monoclonal antibody (cMoAb) that significantly improves survival in high-risk neuroblastoma, was previously reported to be highly variable in children, and its clearance (CL, 130 mL/h · m2) and volume of distribution (Vdss, 32 L/m2) were >10-fold higher than the CL and Vdss of other cMoAbs. Characterizing the PK of ch14.18 and the factors responsible for its variability could lead to alternative dosing strategies that reduce toxicity. Methods: Detailed PK sampling was performed prior to, during and for 25 d after 4 daily 10 h infusions of 25 mg/m2 of ch14.18 administered with sargramostim (ANBL0032) in children enrolled on an IRB-approved institutional correlative protocol supported by United Therapeutics Corp. Ch14.18 concentrations were measured with a validated ELISA with a lower limit of detection of 0.44 mcg/mL. PK parameters were derived using non-compartmental methods and reported as median (range). Results: 5 males and 4 females, median (range) age 3.5 (1-7) yrs, have been enrolled. Six were studied on cycle 1 (C1), 2 on C5 and 1 on C3; 3 of 6 patients studied on C1 were re-studied on C3. Data from 3 patients are not included because pre-treatment plasma samples contained a substance that interfered with the ELISA. The Cmax after the 4th daily infusion was 14 (10-24) mcg/mL, and ch14.8 was undetectable at day 25 in 3/6 patients. The half-life was 220 (120-390) h, and the CL was 11 (3.8-16) mL/h · m2, which is similar to the average CL of 4 other cMoAbs (11 mL/h · m2). The Vdss of 2.8 (1.2-3.9) L/m2 approximated blood volume and was similar to the Vdss of other cMoAbs (1.7 L/m2) and humanized MoAbs (2.8 L/m2). AUC0-∞ in 2 patients studied twice were 3440 and 1540 mcg · h/mL on C1 and 2760 and 2690 mcg · h/mL on C3. Conclusions: Ch14.18 CL, Vdss and half-life in children are similar to those in adults receiving ch14.18 at the same dose and similar to other cMoAbs. Ch14.18 PK in children was less variable than previously reported. The identity of the interfering substance in the plasma of some patients requires further investigation. A limited sampling strategy will be developed from these data for use in larger multi-institutional PK studies of ch14.18.

Chiral Inorganic Solid Material Development

2012 ◽  
Vol 463-464 ◽  
pp. 210-214
Author(s):  
Liang Min ◽  
Guo Liang Xu ◽  
Yi Min Liu ◽  
Wen Hua Yao
Keyword(s):  
Mesoporous Materials ◽  
Mesoporous Material ◽  
Stationary Phases ◽  
Solid Material ◽  
Research Issue ◽  
Material Development

After the invention of mesoporous material, the chiral mesoporous materials had been regarded as a hot research issue. Inspired by the chiral phenomenon, in this investigation, we presented several aspect of chiral mesoporous material from its first appearance, especially stated the template that could be used to prepare chiral mesoporous material, including chiral template and achiral template, besides, the different mechanisms and several distinguished scientists’ works were introduced, and some application of these material were introduced such as catalyst, HPLC stationary phases and many other fields.

scholarly journals Sensing Heavy Metals Using Mesoporous-Based Optical Chemical Sensors

2013 ◽  
Vol 2013 ◽  
pp. 1-13 ◽  
Author(s):  
Špela Korent Urek ◽  
Nina Frančič ◽  
Matejka Turel ◽  
Aleksandra Lobnik
Keyword(s):  
Heavy Metal ◽  
Mesoporous Materials ◽  
Optical Sensors ◽  
Chemical Sensors ◽  
Chemical Sensor ◽  
Limit Of Detection ◽  
Good Alternative ◽  
High Porosity ◽  
Optical Chemical Sensors ◽  
Materials Used

Heavy metal pollution is one of the more serious environmental problems; therefore, there is a constant demand for the development of new analytical tools for its monitoring. An optical chemical sensor represents a good alternative to classical instrumental methods. The mesoporous materials used in optical chemical sensors’ fabrications have properties such as high porosity, exceptional adsorption capacity, tuneable 3D shape, geometry, and morphology, which enable improved limit of detection, response time, and selectivity properties of optical sensors. In this review, we firstly present the properties of mesoporous materials, provide a brief description of sensing mechanisms, and briefly discuss the importance of continuous monitoring. Recent advances in those mesoporous silica-based optical sensors used for heavy metal detection have been reported and their advantages and limitations also discussed. This review covers publications that have appeared since 2008.

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