Ratiometric array of conjugated polymers–fluorescent protein provides a robust mammalian cell sensor

© 2016 American Chemical Society.Supramolecular complexes of a family of positively charged conjugated polymers (CPs) and green fluorescent protein (GFP) create a fluorescence resonance energy transfer (FRET)-based ratiometric biosensor array. Selective multivalent interactions of the CPs with mammalian cell surfaces caused differential change in FRET signals, providing a fingerprint signature for each cell type. The resulting fluorescence signatures allowed the identification of 16 different cell types and discrimination between healthy, cancerous, and metastatic cells, with the same genetic background. While the CP-GFP sensor array completely differentiated between the cell types, only partial classification was achieved for the CPs alone, validating the effectiveness of the ratiometric sensor. The utility of the biosensor was further demonstrated in the detection of blinded unknown samples, where 121 of 128 samples were correctly identified. Notably, this selectivity-based sensor stratified diverse cell types in minutes, using only 2000 cells, without requiring specific biomarkers or cell labeling

flame atomic absorption spectrometry (MIS-FAAS)

Magnetic nanoparticles (MNPs) named Fe3O4@coPANI-PTH were synthesized by coating Fe(3)O(4)nanoparticles (NPs) with a polyaniline (PANI)/polythiophene (PTH) co-polymer. The feasibility of Fe3O4@coPANI-PTH as the nanosorbent for magnetic solid-phase extraction (MSPE) was evaluated for the determination of Co(II) in real samples using microsample injection system - flame atomic absorption spectrometry (MIS-FAAS). Parameters (sample pH, adsorbent mass, eluent volume, sample volume, and co-existing ion effects) influencing the preconcentration of cobalt were optimized. Under the optimum conditions at pH 10, cobalt was completely adsorbed by 100 mg Fe3O4@coPANI-PTH from 60 mL sample and eluted quantitatively (>= 95%) using 1.0 mL of 0.2% thiourea solution in a mixture of 2 mol L-1HCl and 1 mol L-1HNO3. The adsorption capacity and characteristics of Fe3O4@coPANI-PTH for cobalt were evaluated with isotherm studies. The accuracy of the optimized method was evaluated by measuring certified reference materials (CRMs) and spiked real samples. The relative error and standard deviation were below 6.0% for the CRM and real sample analyses. The limit of detection was 1.6 mu g L-1. The determination of ultra-trace cobalt amounts in various soft drinks, spice, vegetable, and water samples was achieved satisfactorily with this method.C1 [Elci, Sukru Gokhan] Pamukkale Univ, Biomed Engn Dept, Technol Fac, TR-20017 Denizli, Turkey

determination of nickel and copper in soft drinks and spice samples

A magnetic solid-phase extraction using magnetite coated with polyaniline-polythiophene copolymer (Fe3O4@coPANI-PTH) was applied for preconcentration of Ni(II) and Cu(II) in some soft drinks and spice samples followed by microsample injection system-flame atomic absorption spectrometry (MIS-FAAS). Preconcentration optimisations including pH, amount of adsorbent, eluent type and volume, sample volume, interfering ion effects were investigated. Relative recoveries of 85.2-96.8% were satisfactorily obtained by extracting both analytes from 50 mL sample solution buffered at pH 10 to 0.5 mL eluent using 100 mg Fe3O4@coPANI-PTH. Good linearity was obtained ranging from 5 to 80 mu g L(-1)with a regression coefficient of 0.999. Limits of detection for Ni(II) and Cu(II) were 2.8 and 1.2 mu g L-1, respectively. The accuracy of the method was confirmed by the analysis of certified reference samples and real samples spiked with the analytes. The relative error and standard deviation of the current method for both analytes were smaller than 6%. The established method was applied to commercially available some local soft drinks and spice samples.C1 [Elci, Sukru Gokhan] Pamukkale Univ, Fac Technol, Dept Biomed Engn, Denizli, Turkey

chlorophenols in water samples

Solid-phase extraction (SPE) followed by derivatization and gas chromatography-atomic emission detection (GC-AED) was evaluated for the determination of five chlorophenols (CPs) in water samples. The derivatization was based on the esterification of phenolic compounds with ferrocenecarboxylic acid. The determination of the derivatized phenols was performed by GC-AED in the iron selective detection mode at 302 nm. The described method was tested on spiked water samples. The overall method gave detection limits of 1.6-3.7 ng L(-1) and recoveries of 90.9-104.5% for the examined mono- to trichlorophenols in 10 mL water samples. The CPs extracted from a 10 mL water sample with SPE were concentrated into 100 mu L of organic solvent, a preconcentration factor of 100. The method was applied to lake and tap water samples, and CP contents between 6 and 51 ng L(-1) in lake water and between below the detection limit and 8 ng L(-1) in tap water were found for different CPs. The method is quick, simple and gives excellent recoveries, limits of detection and standard deviations. (C) 2011 Elsevier B.V. All rights reserved

in water and fish tissue samples

An aminated Amberlite XAD-resin as a solid phase extractant was tested for speciation of inorganic mercury, Hg (II) and methylmercury, MeHg(I) in water and fish tissue samples. It was found that Hg(II) and MeHg(I) ions could be simultaneously retained by a column filled with AAXAD-4 resin at pH 4 and the sequential quantitative elutions of Hg(II) and MeHg(I) were achieved using 10 mL of 0.1%(m/v) thiourea in 3%(v/v) HCl and 10 mL of 6 mol L-1 HCl, respectively. Hg(II) in the eluent was directly determined and MeHg(I) in the second eluent is quantified using FI-CVG-AAS after its oxidative digestion with KMnO4. The limits of detection for Hg(II) and MeHg(I) ions were found to be 0.148 and 0.157 mu g L-1, respectively. The method was validated by analysing a certified reference material. The relative errors for Hg(II), MeHg(I) and T-Hg were in range of -1.8% and -3.2%.C1 [Caylak, Osman] Pamukkale Univ, Vocat Sch Tech Sci, Chem Dept, TR-20017 Denizli, Turkey.[Elci, Sukru Gokhan] Pamukkale Univ, Technol Fac, Biomed Engn Dept, TR-20017 Denizli, Turkey.[Hol, Aysen; Divrikli, Umit; Elci, Latif] Pamukkale Univ, Fac Sci & Art, Chem Dept, TR-20017 Denizli, Turkey.[Akdogan, Abdullah] Pamukkale Univ, Fac Engn, Chem Engn Dept, TR-20017 Denizli, Turkey

A Multichannel Biosensor for Rapid Determination of Cell Surface Glycomic Signatures.

Cell surface glycosylation serves a fundamental role in dictating cell and tissue behavior. Cell surface glycomes differ significantly, presenting viable biomarkers for identifying cell types and their states. Glycoprofiling is a challenging task, however, due to the complexity of the constituent glycans. We report here a rapid and effective sensor for surface-based cell differentiation that uses a three-channel sensor produced by noncovalent conjugation of a functionalized gold nanoparticle (AuNP) and fluorescent proteins. Wild-type and glycomutant mammalian cells were effectively stratified using fluorescence signatures obtained from a single sensor element. Blinded unknowns generated from the tested cell types were identified with high accuracy (44 out of 48 samples), validating the robustness of the multichannel sensor. Notably, this selectivity-based high-throughput sensor differentiated between cells, employing a nondestructive protocol that required only a single well of a microplate for detection