An immunochromatographic strip sensor for marbofloxacin residues.

Marbofloxacin (MBF) was once widely used as a veterinary drug to control diseases in animals. MBF residues in animal food endanger human health. In the present study, an immunochromatographic strip assay (ICSA) utilizing a competitive principle was developed to rapidly detect MBF in beef samples.

Multiphysics Modeling of Plasmonic Photothermal Heating Effects in Gold Nanoparticles and Nanoparticle Arrays.

Induced hyperthermia has been demonstrated as an effective oncological treatment due to the reduced heat tolerance of most malignant tissues; however, most techniques for heat generation within a target volume are insufficiently selective, inducing heating and unintended damage to surrounding healthy tissues. Plasmonic photothermal therapy (PPTT) utilizes light in the near-infrared (NIR) region to induce highly localized heating in gold nanoparticles, acting as exogenous chromophores, while minimizing heat generation in nearby tissues. However, optimization of treatment parameters requires extensive and studies for each new type of pathology and tissue targeted for treatment, a process that can be substantially reduced by implementing computational modeling.

Colloidal gold-based immunochromatographic strip assay for the rapid detection of diminazene in milk.

Diminazene (DIM) is widely used to treat trypanosomiasis in livestock, but its residues in animal products can cause food safety problems. Thus, a rapid colloidal gold-based immunochromatographic strip assay was established to analyse DIM residue in milk samples. A highly sensitive and specific monoclonal antibody (mAb) against DIM was produced with a new synthetic immunogen by the active ester method.

Colloidal gold-based immunochromatographic strip assay for the rapid detection of bacitracin zinc in milk.

In this study, a murine monoclonal antibody (mAb) of 6D2-G10 against bacitracin zinc (BAC) was produced and applied to an immunochromatographic strip (ICS) for the initial detection of BAC in milk. The ICS with a cut-off value of 25 ng/mL could be perceived by the naked eye within 10 min. With the assist of the strip reader, the limit of detection (LOD) was measured as 0.

A highly sensitive monoclonal antibody-based paper sensor for simultaneously detecting valnemulin and tiamulin in porcine liver.

Valnemulin (VAL) and tiamulin (TIA) are pleuromutilin antibiotics used primarily for treating bacterial infections in swine or other food animals. Furthermore, VAL and TIA are also employed as feed additives to promote animal growth. However, the illegal use of VAL and TIA could cause a series of hazards to consumers.

Gold Nanoparticle Aggregation-Induced Quantitative Photothermal Biosensing Using a Thermometer: A Simple and Universal Biosensing Platform.

A simple, low-cost, and universal gold nanoparticle (AuNP) aggregation-induced photothermal biosensing platform has been developed for the first time and applied for the visual quantitative genetic detection using a common thermometer. By exploiting the photothermal effect of target-induced gold nanoparticle aggregation, visual quantitative biochemical analysis can be achieved by simply recording temperature signals using a common thermometer. Compared to conventional genetic testing methods, it is label- and amplification-free and can be completed in 40 min without the aid of any advanced analytical instruments.

A rapid colloidal gold-based immunochromatographic strip assay for monitoring nitroxynil in milk.

Background: Nitroxynil (NIT) is a veterinary drug against hepatic fluke disease for food-producing cattle and sheep. NIT has a long half-life time in animals since it is highly bound to plasma protein. Therefore NIT possibly remains in animal edible tissues or milk due to drug abuse.

Single Primer Based Multisite Strand Displacement Reaction Amplification Strategy for Rapid Detection of Terminal Deoxynucleotidyl Transferase Activity.

A fluorescence-based multisite strand displacement reaction (MSSDR) amplification strategy is developed for the rapid, sensitive, and selective detection the activity of terminal deoxynucleotidyl transferase (TdT). Oligo dT primer was used for the TdT extension reaction, then the left oligo dT primers were hybridized to the TdT extension reaction product by end to end tiled style and initiated the MSSDR by Klenow polymerase, subsequently, 3' terminals of these single-strand DNA produced by MSSDR are folded back to complement themselves with the adjacent sequences, and Klenow polymerase makes it into double-stranded DNA (dsDNA). The final dsDNA products were analyzed via dsDNA specific fluorescent dye.

A cucurbit[8]uril sponge.

This paper describes a convenient approach to quantitative removal of the synthetic host cucurbit[8]uril (Q8) from aqueous mixtures using a sepharose resin coated in memantine groups to selectively sequester Q8 in the presence of competing hosts and guests. The "Q8 sponge" can separate Q8 from Q6 and reverse the Q8-mediated dimerization of peptides.

Nanomolar binding of peptides containing noncanonical amino acids by a synthetic receptor.

This paper describes the molecular recognition of phenylalanine derivatives and their peptides by the synthetic receptor cucurbit[7]uril (Q7). The 4-tert-butyl and 4-aminomethyl derivatives of phenylalanine (tBuPhe and AMPhe) were identified from a screen to have 20-30-fold higher affinity than phenylalanine for Q7. Placement of these residues at the N-terminus of model tripeptides (X-Gly-Gly), resulted in no change in affinity for tBuPhe-Gly-Gly, but a remarkable 500-fold increase in affinity for AMPhe-Gly-Gly, which bound to Q7 with an equilibrium dissociation constant (K(d)) value of 0.