Rubber and rubber latices. Determination of manganese content. Sodium periodate photometric methods

2015 ◽  
1986 ◽  
Vol 32 (5) ◽  
pp. 748-751 ◽  
Author(s):  
H Saruta ◽  
Y Ashihara ◽  
M Sugiyama ◽  
M Roth ◽  
E Miyagawa ◽  
...  

Abstract This simple, reproducible colorimetric method for determining the activity of carboxypeptidase A (EC 3.4.17.1) is based on measuring the absorbance at 505 nm of a quinoneimine dye produced from the action of this enzyme on the new substrate p-hydroxybenzoyl-glycyl-L-phenylalanine. The enzyme acts on the substrate to produce p-hydroxybenzoyl-glycine and L-phenylalanine. The former is then hydrolyzed by hippuricase (EC 3.5.1.14) to produce p-hydroxybenzoic acid and glycine. Finally, oxidative coupling of p-hydroxybenzoic acid with 4-aminoantipyrine by sodium periodate forms a quinoneimine dye. The Km for the reaction with this substrate is 3.6 mmol/L; the optimum pH is 7.8. Our within-run and between-run CVs are 4.3% and 6.6%, respectively. The activity of carboxypeptidase A in serum correlates well with that of lipase (r = 0.96) and immunoreactive elastase-1 (r = 0.76).


Planta Medica ◽  
2018 ◽  
Vol 84 (14) ◽  
pp. 1038-1044 ◽  
Author(s):  
Benyakan Pongkitwitoon ◽  
Seiichi Sakamoto ◽  
Rika Nagamitsu ◽  
Waraporn Putalun ◽  
Hiroyuki Tanaka ◽  
...  

AbstractHomoharringtonine (HHT), also known as omacetaxine, is a natural compound found in the genus Cephalotaxus and is a promising pharmaceutical drug used for the treatment of chronic or accelerated phase chronic myeloid leukemia. As a tool for the quantitative determination of HHT, a specific monoclonal antibody against HHT (MAb 6A1) was generated by conjugates prepared via sodium periodate-mediated oxidation. The developed indirect competitive enzyme-linked immunosorbent assay (icELISA) using MAb 6A1 was found to be highly specific and sensitive with a limit of detection for HHT of 48.8 ng/mL. Validation assays to evaluate precision and accuracy of the method were conducted by the use of intra- and inter-assay analysis, recovery test, and comparison analysis between the amounts of HHT determined by ELISA and high-performance liquid chromatography. These results revealed that the established icELISA using MAb 6A1 is specific, sensitive, and reliable enough to be applied to the qualitative analysis for HHT. Furthermore, the results of this study support the usefulness of sodium periodate as a reagent for the conjugation between Cephalotaxus alkaloids and proteins for producing specific antibodies.


Author(s):  
Małgorzata STOJEK

Studies of molybdenum and manganese content in topsoil and plants were carried out in the Beskidy Wschodnie (Carpathians) in area of occurrence of menilite shales and the Otryt sandstones. The aim of the study was to evaluate the content of ­molybdenum and manganese in plants and the determination of a bioaccumulation of these two chemical elements in two species of plants (­Trifolium hybridum L. and Plantago major L.). Mo symbols were performed by means of ICP-MS method, and Mn were analyzed by means of ICP-OES method. Result of studies in the Trifolium hybridum L. have shown higher content of Mo in the area of occurence of menilite shales (in leaves – 14 mg/kg) than in the Otryt sandstones (in leaves – 0.30 mg/kg). Most Mn accumulates in leaves (86–257 mg/kg). The bioaccumulate indicator of Mo in individual plant species is different and ranges from 0.13 to 1.13. The highest rate of ­bioaccumulation of molybdenum (1.13) can be observed in Trifolium hybridum L., which inhabits areas of menilite shales.


2012 ◽  
Vol 554-556 ◽  
pp. 2064-2067
Author(s):  
Jin Yang ◽  
Wei Liu ◽  
Bao Sheng Wang ◽  
Qing Hua Li ◽  
Ping Yi ◽  
...  

In this research the atomic absorption spectroscopy method (the correlation coefficient was 0.9995) was employed for determination of the content of heavy metal-manganese in panax pseudo-ginseng var. notoginseng, which was chosen as the sample. The optimum conditions of two pretreatments were researched independently. In the dry ashing, the optimized temperature and time are 600°C and 4~6 hours respectively, and the manganese content determined is 53.16 ug/g and the recovery rate of manganese added in sample is 98.64%. In the wet digestion, The HNO3-H2O2 digestion system is the best one, and the content was 52.95ug/g and the recovery rate is 97.30%. So the two pretreatment methods of the sample are accurate enough on manganese content determination. But the dry ashing is better than the wet digestion relatively.


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