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https://www.readbyqxmd.com/read/30318543/a-novel-paper-based-colorimetry-device-for-the-determination-of-the-albumin-to-creatinine-ratio
#1
Sudkate Chaiyo, Kurt Kalcher, Amara Apilux, Orawon Chailapakul, Weena Siangproh
A novel paper-based analytical device (PAD) was fabricated and developed for the simple and rapid determination of the albumin to creatinine ratio (ACR) in urine samples. The detection was based on a colorimetric reaction using bromocresol green (BG) in a phosphate buffer (PB) at pH 4 for the determination of albumin (AL) and creatinine (CR). BG changes color from greenish-yellow to bluish-green in the presence of AL and/or CR. Picric acid (PA) in 0.25 M NaOH was used to detect CR, and PA changes color from yellow to orange...
October 15, 2018: Analyst
https://www.readbyqxmd.com/read/30314259/potential-of-grape-wastes-as-a-natural-source-of-bioactive-compounds
#2
Guo-Yi Tang, Cai-Ning Zhao, Qing Liu, Xiao-Ling Feng, Xiao-Yu Xu, Shi-Yu Cao, Xiao Meng, Sha Li, Ren-You Gan, Hua-Bin Li
Grapes are widely used in the wine and juice industries, which can lead to massive amounts of waste, mostly grape peels and seeds. The antioxidant capacities, total phenolic and flavonoid contents and phenolic profiles of peels and seeds from 30 grape varieties were systemically assessed. The antioxidant activities of fat-soluble, water-soluble and insoluble-bound fractions of grape peels and seeds were evaluated using ferric-reducing antioxidant power and Trolox equivalent antioxidant capacity assays, and their total phenolic contents and total flavonoid contents were determined by the Folin-Ciocalteu method and AlCl₃ colorimetry, respectively...
October 11, 2018: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
https://www.readbyqxmd.com/read/30309551/impact-of-a-post-fermentative-maceration-with-overripe-seeds-on-the-color-stability-of-red-wines
#3
Francisco J Rivero, M José Jara-Palacios, Belén Gordillo, Francisco J Heredia, M Lourdes González-Miret
With the purpose of modulating the copigmentation equilibria of red wines, an environmentally sustainable process was performed based on post-fermentative addition of overripe seeds (OS). Simple (SW) and double (DW) addition were performed to produce different enrichment of phenolics from seeds, hence different copigmentation/polymerization ratios. The determination of the phenolic composition showed different global increases in OS-macerates wines (catechin, epicatechin, gallic acid and procyanidins B1 and B2)...
January 30, 2019: Food Chemistry
https://www.readbyqxmd.com/read/30302673/analysis-of-multifloral-bee-pollen-pellets-by-advanced-digital-imaging-applied-to-functional-food-ingredients
#4
Claudia Y Salazar-González, Francisco J Rodríguez-Pulido, Anass Terrab, Consuelo Díaz-Moreno, Carlos A Fuenmayor, Francisco J Heredia
Bee pollen is a hive product, resulting from floral pollen agglutination by worker bees and it is characterized by its excellent bioactive and nutritional composition. Currently, research is focused on bee pollen applications on food industry, because this product has been considered an excellent source of compounds for human nutrition. It is also important in some industries, where color and particle size are important characteristics for production. Due to the granular nature of bee pollen, conventional colorimetry does not allow describing color correctly; thus, digital image analysis is a better alternative...
October 9, 2018: Plant Foods for Human Nutrition
https://www.readbyqxmd.com/read/30292149/portable-and-selective-colorimetric-film-and-digital-image-colorimetry-for-detection-of-iron
#5
Aree Choodum, Wilasinee Sriprom, Worawit Wongniramaikul
Iron is an important trace element in environmental and biological systems, the development of simple and selective methods for the determination of iron is important. In this work, completely biodegradable tapioca starch was introduced as the substrate to entrap standard chromogenic probes (1,10-phenanthroline) for fabrication of a novel colorimetric sensor for ferrous. A clear plasticized thin film from tapioca starch was fabricated inside a small plastic tube as a portable test kit. A red complex was obtained by exposing the film to a ferrous solution, while no color changes were obtained with various other ions, indicating excellent selectivity...
October 2, 2018: Spectrochimica Acta. Part A, Molecular and Biomolecular Spectroscopy
https://www.readbyqxmd.com/read/30289315/regulation-of-free-fatty-acids-by-sitagliptin-monotherapy-in-drug-na%C3%A3-ve-subjects-with-type-2-diabetes
#6
Eiji Kutoh, Asuka Wada, Jyunka Hayashi
OBJECTIVES: The aim of this study is to investigate the effects of sitagliptin on the regulation of FFA and other metabolic parameters in drug-naïve subjects with T2DM. SUBJECTS AND METHODS: This is a prospective, non-randomized, observational study. Drug naïve subjects with T2DM received 25-50 mg/day sitagliptin monotherapy (n=64). At 3 months, FFA and other metabolic parameters were compared with those at baseline. FFA was measured by colorimetry with enzymatic reactions...
October 5, 2018: Endocrine Practice
https://www.readbyqxmd.com/read/30284031/an-optoelectronic-tongue-based-on-an-array-of-gold-and-silver-nanoparticles-for-analysis-of-natural-synthetic-and-biological-antioxidants
#7
Mohammad Mahdi Bordbar, Bahram Hemmateenejad, Javad Tashkhourian, S F Nami-Ana
A colorimetric array, which can discriminate 20 food antioxidants of natural, synthetic and biological groups, is described. It consists of gold and silver nanoparticles that were synthesized using six different reducing and/or capping agents. The function of the array relies on the interaction of the antioxidants with the nanoparticles which causes aggregation or morphological changes. This, in turn, causes a change in the sensors' colors. The array produces a unique combination of colors for each antioxidant...
October 3, 2018: Mikrochimica Acta
https://www.readbyqxmd.com/read/30275700/analysis-nutrition-and-health-benefits-of-tryptophan
#8
REVIEW
Mendel Friedman
Tryptophan is an essential plant-derived amino acid that is needed for the in vivo biosynthesis of proteins. After consumption, it is metabolically transformed to bioactive metabolites, including serotonin, melatonin, kynurenine, and the vitamin niacin (nicotinamide). This brief integrated overview surveys and interprets our current knowledge of the reported multiple analytical methods for free and protein-bound tryptophan in pure proteins, protein-containing foods, and in human fluids and tissues, the nutritional significance of l-tryptophan and its isomer d-tryptophan in fortified infant foods and corn tortillas as well the possible function of tryptophan in the diagnosis and mitigation of multiple human diseases...
2018: International Journal of Tryptophan Research: IJTR
https://www.readbyqxmd.com/read/30264681/development-of-biodegradable-injectable-in-situ-forming-implants-for-sustained-release-of-lornoxicam
#9
Ruby Christian, Vaishali Thakkar, Tushar Patel, Mukesh Gohel, Lalji Baldaniya, Purvi Shah, Tosha Pandya, Tejal Gandhi
OBJECTIVE: The focus of this study was to develop in situ injectable implants of Lornoxicam which could provide sustained drug release. METHODS: Biodegradable in situ injectable implants were prepared by polymer precipitation method using polylactide-co-glycolide (PLGA). An optimized formulation was obtained on the basis of drug entrapment efficiency, gelling behavior and in vitro drug release. The compatibility of the formulation ingredients were tested by Fourier transform infrared (FT-IR) spectroscopy, differential scanning colorimetry (DSC)...
September 27, 2018: Current Drug Delivery
https://www.readbyqxmd.com/read/30255910/effect-of-surface-interfacial-defects-on-photo-stability-of-thick-shell-cdznses-zns-quantum-dots
#10
Bo Huang, Hongyu Yang, Lei Zhang, Yufen Yuan, Yiping Cui, Jiayu Zhang
High color-purity CdZnSeS alloy cores and CdZnSeS/ZnS core/shell quantum dots (QDs) with 3, 11 and 17 monolayer (ML) ZnS shells are synthesized, and the narrow emission (full-width at half-maximum: ∼21 nm) is ascribed to the high size uniformity of QDs and the narrow linewidth of single QD spectra. Ultraviolet (UV) irradiation experiments show that the photo-stabilities of the samples improve remarkably with increasing shell thickness, but the photo-stability clearly decreases when the shell thickness is further increased to 17 MLs...
October 4, 2018: Nanoscale
https://www.readbyqxmd.com/read/30242619/aesthetic-compatibility-assessment-of-consolidants-for-wall-paintings-by-means-of-multivariate-analysis-of-colorimetric-data
#11
Francesca Becherini, Caterina Durante, Elsa Bourguignon, Mario Li Vigni, Vincent Detalle, Adriana Bernardi, Patrizia Tomasin
BACKGROUND AND METHODS: Wall paintings and architectural surfaces in outdoor environments are exposed to several physical, chemical and biological agents, hence they are often treated with different products to prevent or slow down their deterioration. Among the factors that have to be taken into account in the selection of the most suitable treatment for decorated surfaces, the aesthetic compatibility with the substrate is of great importance in the cultural heritage field; minimizing colour variation after treatment application is a crucial issue in particular for painted surfaces...
September 21, 2018: Chemistry Central Journal
https://www.readbyqxmd.com/read/30224617/preparation-of-1l-myo-inositol-1-phosphate-as-a-substrate-of-phosphatidylinositol-phosphate-synthase
#12
Hiroyuki Morii, Takehiro Nishimura, Masahiro Takeo, Chika Katayama, Kana Nakai
Novel drugs possessing a mechanism of action specific to pathogenic mycobacteria, including Mycobacterium tuberculosis, are needed. In 2010, we discovered that the biosynthetic pathway of phosphatidylinositol, which is a membrane phospholipid, differs between humans and mycobacteria. The key enzyme responsible for this difference is phosphatidylinositol phosphate (PIP) synthase, which is present only in a few bacteria belonging to the phylum Actinobacteria. Discovering compounds that inhibit the activity of this enzyme will lead to the development of new drugs specific to pathogenic mycobacteria...
2018: Journal of UOEH
https://www.readbyqxmd.com/read/30220278/-anti-inflammatory-effects-of-penehyclidine-hydrochloride-on-acute-respiratory-distress-syndrome-in-rats
#13
Huixian Xu, Jing Xie, Yanna Lei, Qingsong Cui, Minggen Jin
OBJECTIVE: To investigate the anti-inflammatory effect of penehyclidine hydrochloride on oleic acid-induced acute respiratory distress syndrome (ARDS) in rats. METHODS: According to randomize number table method, 30 adult male Sprague-Dawley (SD) rats were divided into control group, model group and treatment group. Catheters were placed in femoral vein in each group. The control group was injected with 1.1 mL/kg physiological saline; the model group was injected with 0...
August 2018: Zhonghua Wei Zhong Bing Ji Jiu Yi Xue
https://www.readbyqxmd.com/read/30210077/quantitative-31-p-nmr-method-for-individual-and-concomitant-determination-of-phospholipid-classes-in-polar-lipid-samples
#14
Tsuyoshi Kato, Mami Nishimiya, Akiko Kawata, Kyoko Kishida, Kounosuke Suzuri, Maki Saito, Kazuhiro Fujita, Tomoji Igarashi, Minoru Inagaki
Herein, to achieve individual and concomitant quantifications of phospholipid classes, an absolute quantification 31 P NMR method using an internal standard was examined. Phospholipid standards and dietary foods were dispersed to prepare test solutions in an anionic surfactant (sodium cholate) solution containing EDTA, as a modification based on a reported method. Each phospholipid class showed a reproducible chemical shift at a near-neutral test solution pH of 6.90±0.04 and temperature of 30.0±0.1°C. The quantity of synthetic phosphatidylcholine measured using 31 P NMR was consistent with that measured by 1 H NMR using an internal standard...
September 13, 2018: Journal of Oleo Science
https://www.readbyqxmd.com/read/30173507/smartphone-nanocolorimetry-for-on-demand-lead-detection-and-quantitation-in-drinking-water
#15
Hoang Nguyen, Yulung Sung, Kelly O'Shaughnessy, Xiaonan Shan, Wei-Chuan Shih
Lead ions (Pb2+ ) contamination in drinking water, a major source of lead poisoning to the general population, is typically detected by bulky and costly laboratory analytical instrument. A mobile analytical device for rapid Pb2+ sensing is a growing demand. Herein, we report smartphone nanocolorimetry (SNC) as a new technique to detect and quantify dissolved Pb2+ in drinking water. Specifically, we have employed a single-step sedimentation approach by mixing a controlled quantity of chromate ion (CrO4 2- ) to react with Pb2+ containing solutions to form highly insoluble lead chromate (PbCrO4 ) nanoparticles as vivid yellow precipitates...
October 2, 2018: Analytical Chemistry
https://www.readbyqxmd.com/read/30173359/a-ratiometric-fluorometric-and-colorimetric-probe-for-the-%C3%AE-thalassemia-drug-deferiprone-based-on-the-use-of-gold-nanoclusters-and-carbon-dots
#16
Yanying Wang, Lei Mao, Wei Liu, Fang Ding, Ping Zou, Xianxiang Wang, Qingbiao Zhao, Hanbing Rao
A turn-on fluorometric probe is described for the β-thalassemia drug deferiprone (DFP). The probe is making use of carbon dots (C-dots) and gold nanoclusters (AuNCs) which, under 340-nm excitation, display dual emission with peaks at 445 and 592 nm. The orange fluorescence of AuNCs is quenched after the addition of Fe(III), but recovered on addition of DFP. The blue fluorescence of the C-dots, in contrast, remains unchanged. The Fe(III)-DFP complex undergoes intermolecular electron transfer under UV excitation and displays only weak peaks in the UV region...
September 1, 2018: Mikrochimica Acta
https://www.readbyqxmd.com/read/30148962/ultrasensitive-virion-immunoassay-platform-with-dual-modality-based-on-a-multifunctional-aggregation-induced-emission-luminogen
#17
Ling-Hong Xiong, Xuewen He, Zheng Zhao, Ryan T K Kwok, Yu Xiong, Peng Fei Gao, Fan Yang, Yalan Huang, Herman H-Y Sung, Ian D Williams, Jacky W Y Lam, Jinquan Cheng, Renli Zhang, Ben Zhong Tang
Sensitive and accurate detection of highly contagious virus is urgently demanded for disease diagnosis and treatment. Herein, based on a multifunctional aggregation-induced emission luminogen (AIEgen), a dual-modality readout immunoassay platform for ultrasensitive detection of viruses has been successfully demonstrated. The platform is relied on virions immuno-bridged enzymatic hydrolysis of AIEgen, accompanying with the in situ formation of highly emissive AIE aggregates and shelling of silver on gold nanoparticles...
September 25, 2018: ACS Nano
https://www.readbyqxmd.com/read/30142209/bone-marrow-stromal-cells-from-low-turnover-osteoporotic-mouse-model-are-less-sensitive-to-the-osteogenic-effects-of-fluvastatin
#18
Yukari Oda, Hodaka Sasaki, Tadashi Miura, Takuya Takanashi, Yoshitaka Furuya, Masao Yoshinari, Yasutomo Yajima
This study aimed to investigate the effects of fluvastatin on the differentiation of bone marrow stromal cells (BMSCs) into osteoblasts in senescence-accelerated mouse prone 6 (SAMP6) compared with that in the normal senescence-accelerated-resistant mouse (SAMR1) model. SAMP strains arose spontaneously from the AKR/J background and display shortened life span and an array of signs of accelerated aging, compared with control SAMR strains. The dose effects of fluvastatin were also evaluated. BMSCs were cultured with/without fluvastatin (0 μM, 0...
2018: PloS One
https://www.readbyqxmd.com/read/30128961/sitagliptin-improves-renal-function-in-diabetic-nephropathy-in-male-sprague-dawley-rats-through-upregulating-heme-oxygenase-1-expression
#19
Jianping Wang, Lan Hu, Yang Chen, Ting Fu, Tao Jiang, Aihua Jiang, Xiaoxing You
PURPOSE: Oxidative stress is an important mechanism for diabetic nephropathy. Studies showed that hemo oxygenase-1 (HO-1) expression in renal tissue of patients with diabetic nephropathy has upregulated, while the HO-1 can protect the body through anti-oxidative stress. The study aimed to preliminarily explore the molecular mechanism by observing the effect of Sitagliptin on HO-1 expression in renal tissue of rats with diabetic nephropathy. METHODS: The diabetic nephropathy rat model was established by STZ injection followed by intraperitoneal injection of sitagliptin with different concentrations...
August 20, 2018: Endocrine
https://www.readbyqxmd.com/read/30128458/optofluidic-differential-colorimetry-for-rapid-nitrite-determination
#20
Y Shi, H L Liu, X Q Zhu, J M Zhu, Y F Zuo, Y Yang, F H Jiang, C J Sun, W H Zhao, X T Han
Nitrite detection plays a very important role in environmental monitoring and for industrial purposes. The commonly used colorimetric analysis requires the measurement of a system's calibration curve by asynchronously preparing and detecting a dozen standard samples, leading to time-consuming, slow and cumbersome procedures. Here, we present a differential colorimetry method that determines the nitrite level based on the paired chromaticity gradient, formed by coupling the colour reaction into the microfluidic network...
September 26, 2018: Lab on a Chip
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