10 research outputs found
Simultaneous detection of α-Lactoalbumin, β-Lactoglobulin and Lactoferrin in milk by Visualized Microarray
Abstract Background α-Lactalbumin (a-LA), β-lactoglobulin (β-LG) and lactoferrin (LF) are of high nutritional value which have made ingredients of choice in the formulation of modern foods and beverages. There remains an urgent need to develop novel biosensing methods for quantification featuring reduced cost, improved sensitivity, selectivity and more rapid response, especially for simultaneous detection of multiple whey proteins. Results A novel visualized microarray method was developed for the determination of a-LA, β-LG and LF in milk samples without the need for complex or time-consuming pre-treatment steps. The measurement principle was based on the competitive immunological reaction and silver enhancement technique. In this case, a visible array dots as the detectable signals were further amplified and developed by the silver enhancement reagents. The microarray could be assayed by the microarray scanner. The detection limits (S/N = 3) were estimated to be 40 ng/mL (α-LA), 50 ng/mL (β-LG), 30 ng/mL (LF) (n = 6). Conclusions The method could be used to simultaneously analyze the whey protein contents of various raw milk samples and ultra-high temperature treated (UHT) milk samples including skimmed milk and high calcium milk. The analytical results were in good agreement with that of the high performance liquid chromatography. The presented visualized microarray has showed its advantages such as high-throughput, specificity, sensitivity and cost-effective for analysis of various milk samples
Disposable MoS<sub>2</sub>‑Arrayed MALDI MS Chip for High-Throughput and Rapid Quantification of Sulfonamides in Multiple Real Samples
In
this work, we demonstrate, for the first time, the development
of a disposable MoS<sub>2</sub>-arrayed matrix-assisted laser desorption/ionization
mass spectrometry (MALDI MS) chip combined with an immunoaffinity
enrichment method for high-throughput, rapid, and simultaneous quantitation
of multiple sulfonamides (SAs). The disposable MALDI MS chip was designed
and fabricated by MoS<sub>2</sub> array formation on a commercial
indium tin oxide (ITO) glass slide. A series of SAs were analyzed,
and clear deprotonated signals were obtained in negative-ion mode.
Compared with MoS<sub>2</sub>-arrayed commercial steel plate, the
prepared MALDI MS chip exhibited comparable LDI efficiency, providing
a good alternative and disposable substrate for MALDI MS analysis.
Furthermore, internal standard (IS) was previously deposited onto
the MoS<sub>2</sub> array to simplify the experimental process for
MALDI MS quantitation. 96 sample spots could be analyzed within 10
min in one single chip to perform quantitative analysis, recovery
studies, and real foodstuff detection. Upon targeted extraction and
enrichment by antibody conjugated magnetic beads, five SAs were quantitatively
determined by the IS-first method with the linear range of 0.5–10
ng/mL (<i>R</i><sup>2</sup> > 0.990). Good recoveries
and
repeatability were obtained for spiked pork, egg, and milk samples.
SAs in several real foodstuffs were successfully identified and quantified.
The developed method may provide a promising tool for the routine
analysis of antibiotic residues in real samples
Simultaneous detection of four nitrofuran metabolites in honey by using a visualized microarray screen assay
Smartphone-based visualized microarray detection for multiplexed harmful substances in milk
Adipocyte thyroid hormone β receptor-mediated hormone action fine-tunes the intracellular glucose and lipid metabolism and systemic homeostasis
Thyroid hormone (TH) has a profound effect on energy metabolism and systemic homeostasis. Adipose tissues are crucial for maintaining whole-body homeostasis, however, whether TH regulates systemic metabolic homeostasis through its action on the adipose tissues is unclear. Here, we demonstrate that systemic administration of triiodothyronine (T3), the active form of TH, affects both inguinal white adipose tissue (iWAT) and whole-body metabolism. Taking advantage of the mouse model lacking adipocyte TH receptor α (TRα) or β (TRβ) we show that TRβ is the major TR isoform that mediates the T3 action on the expression of genes involved in multiple metabolic pathways in iWAT, including glucose uptake and usage, de novo fatty acid synthesis, and both UCP1-dependent and -independent thermogenesis. Moreover, our results indicate that ChREBP in iWAT is regulated by T3, thereby being critically involved in T3-regulated glucose and lipid metabolism and energy dissipation. Meanwhile, mice with adipocyte TRβ deficiency are susceptible to diet-induced obesity and metabolic dysregulation, suggesting that TRβ in adipocytes may sever as a potential target for metabolic diseases. </p