Direct and Highly Selective Drug Optosensing in Real, Undiluted Biological Samples with Quantum-Dot-Labeled Hydrophilic Molecularly Imprinted Polymer Microparticles

Quantum-dot (QD)-labeled hydrophilic molecularly imprinted polymer (MIP) microparticles were prepared for direct and highly selective optosensing of an antibiotic drug (i.e., tetracycline (Tc)) in pure bovine/goat milks and bovine/porcine serums. “Living” CdTe QD–SiO₂ composite microparticles with alkyl bromide groups on their surfaces were first obtained via the one-pot sol–gel reaction, and they were subsequently grafted with a Tc-imprinted polymer layer and poly­(glyceryl monomethacrylate) brushes via the successive surface-initiated atom transfer radical polymerizations. The resulting MIP microparticles with QD labeling and hydrophilic polymer brushes could function properly in biological samples and showed obvious template-binding-induced fluorescence quenching, which make them a useful fluorescent chemosensor with limits of detection down to 0.14 μM in complex biological media. Moreover, a facile and effective approach was developed based on a newly derived equation to eliminate the false positives of the fluorescent chemosensor and provide it with wider linear detection concentration ranges in comparison with those obtained using the generally adopted Stern–Volmer equation. Furthermore, the fluorescent MIP chemosensor was also successfully applied for directly, sensitively, selectively, and accurately quantifying Tc in biological media, and the average recoveries were in the range of 95%∼105% even when several other drugs and the fluorescently interfering chlortetracycline were present in the samples

Hydrophobic/Hydrophilic Triblock Copolymers: Synthesis and Properties of Physically Cross-Linked Hydrogels

Hydrophobic/hydrophilic triblock copolymers of poly­(2-(<i>N</i>-ethylperfluorooctane­sulfonamido)­ethylmethyl acrylate) and poly­(<i>N,N</i>′-dimethylacrylamide) (PD) were synthesized by sequential reversible addition–fragmentation chain transfer polymerization. Physically cross-linked hydrogels were produced by immersing compression-molded triblock copolymers into water. The copolymers and their hydrogels were characterized by differential scanning calorimetry, thermogravimetric analysis, thermal desorption-GC/MS analysis, swelling isotherms, wide- and small-angle X-ray scattering, and dynamic mechanical analysis. The equilibrium water sorption of the hydrogels depended on the length of the water-soluble polymer block (PD), and the block copolymers swelled more in water than a random copolymer of the same composition. The block copolymer hydrogels were viscoelastic, though the frequency dependence of the dynamic modulus was weak. The dynamic modulus of the block copolymer hydrogels ranged from ∼10³ to 4 × 10⁴ Pa, which was much lower than the modulus of a random copolymer hydrogel of the same composition

Hydrophilic Hollow Molecularly Imprinted Polymer Microparticles with Photo- and Thermoresponsive Template Binding and Release Properties in Aqueous Media

A facile, general, and efficient approach to prepare hydrophilic hollow molecularly imprinted polymer (MIP) microparticles with photo- and thermoresponsive template binding and release behaviors in aqueous media is described, which includes the preparation of uniform “living” silica submicrospheres bearing surface atom transfer radical polymerization (ATRP)-initiating groups (i.e., alkyl halide groups) via a one-pot sol–gel method, their subsequent grafting of azobenzene (azo)-containing MIP shell and poly­(<i>N</i>-isopropylacrylamide)-<i>block</i>-poly­(2-hydroxyethyl methacrylate) (PNIPAAm-<i>b</i>-PHEMA) brushes via successive surface-initiated ATRP, and final removal of the silica core. The successful synthesis of such hydrophilic hollow MIP microparticles was confirmed with SEM, FT-IR, water dispersion stability, and static contact angle studies. They proved to show apparently higher template binding capacities than the corresponding solid ones and obvious photo- and thermoresponsive template binding properties in aqueous solutions. Moreover, their pronounced light- and temperature-controlled template release in aqueous media was also demonstrated. In particular, the introduction of PNIPAAm-<i>b</i>-PHEMA brushes onto hollow MIP microparticles imparted them with high surface hydrophilicity both below and above the lower critical solution temperature of PNIPAAm, which paves the way for their applications in such areas as controlled drug/chemical delivery and smart bioanalysis

Table_1_Screening of mRNA markers in early bovine tuberculosis blood samples.XLSX

Bovine tuberculosis (bTB) is a chronic zoonotic disease caused by Mycobacterium bovis. A large number of cattle are infected with bTB every year, resulting in huge economic losses. How to control bTB is an important issue in the current global livestock economy. In this study, the original transcriptome sequences related to this study were obtained from the dataset GSE192537 by searching the Gene Expression Omnibus (GEO) database. Our differential gene analysis showed that there were obvious biological activities related to immune activation and immune regulation in the early stage of bTB. Immune-related biological processes were more active in the early stage of bTB than in the late. There were obvious immune activation and immune cell recruitment in the early stage of bTB. Regulations in immune receptors are associated with pathophysiological processes of the early stage of bTB. A gene module consisting of 236 genes significantly related to the early stage of bTB was obtained by weighted gene co-expression network analysis, and 18 hub genes were further identified as potential biomarkers or therapeutic targets. Finally, by random forest algorithm and logistic regression modeling, FCRL1 was identified as a representative mRNA marker in early bTB blood. FCRL1 has the potential to be a diagnostic biomarker in early bTB.</p

Image_1_Screening of mRNA markers in early bovine tuberculosis blood samples.pdf

Bovine tuberculosis (bTB) is a chronic zoonotic disease caused by Mycobacterium bovis. A large number of cattle are infected with bTB every year, resulting in huge economic losses. How to control bTB is an important issue in the current global livestock economy. In this study, the original transcriptome sequences related to this study were obtained from the dataset GSE192537 by searching the Gene Expression Omnibus (GEO) database. Our differential gene analysis showed that there were obvious biological activities related to immune activation and immune regulation in the early stage of bTB. Immune-related biological processes were more active in the early stage of bTB than in the late. There were obvious immune activation and immune cell recruitment in the early stage of bTB. Regulations in immune receptors are associated with pathophysiological processes of the early stage of bTB. A gene module consisting of 236 genes significantly related to the early stage of bTB was obtained by weighted gene co-expression network analysis, and 18 hub genes were further identified as potential biomarkers or therapeutic targets. Finally, by random forest algorithm and logistic regression modeling, FCRL1 was identified as a representative mRNA marker in early bTB blood. FCRL1 has the potential to be a diagnostic biomarker in early bTB.</p

Film Confinement Induced “Jump-Percolation” Wetting Transition in Amphiphilic Block Copolymer Films

We report a first-order like sharp surface wettability transition with varying film thickness dependent morphology in cast films of an amphiphilic triblock copolymer. Films composed of poly­(2-(<i>N</i>-ethylperfluorooctanesulfonamido) ethyl methyl acrylate), poly­(FOSM), and poly­(<i>N</i>,<i>N</i>′-dimethyl acrylamide), poly­(DMA), with thickness (<i>h</i>) in the transition-range, 200 < <i>h</i> < 300 nm, exhibited an abrupt hydrophobic to hydrophilic dynamic water contact angle transition. After an induction time, <i>t</i>_<i>i</i> ≈ 40 to 180 s, water contact angle varied as θ_c ≈ 116° to 40° with an ultrafast contact angle decay time constant, dθcdt ≈ −18°/s. This behavior is a result of competing heterogeneous and antagonistic effects of bumpy poly­(DMA) wetting domains against a nonwetting planar poly­(FOSM) background, with a “jump percolation” wetting transition when the poly­(DMA) domain density reaches unity. Outside of this film thickness range, relatively shallow decreasing water contact angle gradients were observed with a monotonically increasing poly­(DMA) domain area coverage with increasing film thickness in the overall range of 40 nm (hydrophobic, θ_c ≈ 118°) < <i>h</i> < 500 nm (hydrophilic, θ_c ≈ 8°). The optical diffuse reflectance properties of these rough surfaces exhibit an onset of diffuse reflectance maxima correlated to the transition morphology film thickness

Expression and purification of CDT.

<p>(A) Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) analysis of purified CDT subunits. (B) Western blot analysis of purified CDT subunits using anti-His antibody.</p

Primers for real-time PCR.

<p>Primers for real-time PCR.</p

CdtB activated gamma-H2A.X.

<p>(A) PK-15 cells treated with or without CdtB supplemented with CdtA or CdtC for 24 h as shown, fixed and immuno-stained with γ-H2A.X antibody and DAPI, and then γ-H2A.X foci (green) observed under a confocal microscope. Scale bar corresponds to 200 μm. (B) Flow cytometry analysis of γ-H2A.X in PK-15 cells treated with or without CdtB supplemented with CdtA or CdtC for 24 h as shown, right shift of median fluorescence indicate a net increase of γ-H2A.X. (C) Quantitative Western blot analysis of γ-H2A.X in PK-15 cells treated with or without CdtB supplemented with CdtA or CdtC for 24 h as shown, graphs show normalized level of γ-H2A.X, cells treated without CDT were set as 1. (D) Quantitative analysis of γ-H2A.X in PK-15 cells treated with or without CdtB supplemented with CdtA or CdtC for 24 h by Flow cytometry.</p

The DNase activity of CdtB.

<p>(A) Circular plasmids were incubated with CdtB for 1 h at 37°C and were electrophoresed on an agarose gel and stained with ethidium bromide (EB). (B) Linear plasmids were incubated with CdtB for 1 h at 37°C and analyzed by electrophoresis and staining.</p