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1.
PhytoKeys ; 178: 171-177, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34163299

RESUMEN

Begonia shenzhenensis D.K.Tian & X.Yun Wang, sp. nov., a new species in Begonia sect. Platycentrum of Begoniaceae from Shenzhen of Guangdong province, China, is described and illustrated. Morphologically, it is primarily similar to B. coelocentroides in the same section but differs by its denser hairs on leaf, petiole, and pedicel, abtuse anther apex, hairy ovary, and narrower adaxial fruit wing. Based on only one small population found to date, its conservation status is assigned to Critical Endangered according to the IUCN Red List Categories and Criteria.

2.
PhytoKeys ; 187: 189-205, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-35068975

RESUMEN

Begoniagiganticaulis, a huge new species in Begoniasect.Platycentrum of Begoniaceae from southern Xizang (Tibet) of China, is described. Morphologically, it is mostly similar to B.longifolia and B.acetosella, but clearly differs from the former mainly by its dioecious and taller plants, sparse hairs on abaxial veins, longer inflorescence, unique shape of fruits, and differs from the latter mainly by its late and longer flowering time, 6-tepals of female flower and 3-loculed ovary. The phylogenetic analyses also support the separation of the new species from other taxa. Based on the current data, its conservation status is assigned to Endangered (B2a) according to the IUCN Red List Categories and Criteria.

3.
J Fluoresc ; 16(5): 625-30, 2006 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-17013675

RESUMEN

A new method for the determination of trace mercury by solid substrate-room temperature phosphorimetry (SS-RTP) quenching method has been established. In glycine-HCl buffer solution, xylenol orange (XO) can react with Sn4+ to form the complex [Sn(XO)6]4+. [Sn(XO)6]4+ can interact with Fin- (fluorescein anion) to form the ion associate [Sn(XO)6]4+.[(Fin)4]-, which can emit strong and stable room temperature phosphorescence (RTP) on polyamide membrane (PAM). Hg2+ can catalyze H2O2 oxidizing the ion association complex [Sn(XO)6]4+.[(Fin)4]-, which causes the RTP to quench. The DeltaIp value is directly proportional to the concentration of Hg2+ in the range of 0.016-1.6 fg spot(-1) (corresponding concentration: 0.040-4.0 pg ml(-1), 0.40 microl spot(-1)), and the regression equation of working cure is DeltaIp=10.03+83.15 m Hg2+ (fg spot(-1)), (r=0.9987, n=6) and the detection limit (LD) is 3.6 ag spot(-1)(corresponding concentration: 9.0 x 10(-15) g ml(-1), the sample volume: 0.4 microl). This simple, rapid, accurate method is of high selectivity and good repeatability, and it has been successfully applied to the determination of trace mercury in real samples. The reaction mechanism for catalyzing H2O2 oxidizing the ion association complex ([Sn(XO)6]4+.[(Fin)4]-) SS-RTP quenching method to determine trace mercury is also discussed.


Asunto(s)
Mediciones Luminiscentes/métodos , Mercurio/análisis , Fluoresceínas , Indicadores y Reactivos , Espectrofotometría/métodos
4.
Anal Biochem ; 357(2): 173-80, 2006 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-16942743

RESUMEN

In the presence of heavy atom perturber LiAc, the silicon dioxide nanoparticle containing rhodamine 6G (R) and dibromoluciferin (D) (R-D-SiO(2)) can emit strong and stable solid-substrate room temperature phosphorescence signal of R (lambda(ex)/lambda(em)=481/648 nm) and D (lambda(ex)/lambda(em)=457/622 nm) on the surface of acetyl cellulose membrane (ACM). R-D-SiO(2) is used to label triticum vulgare lectin (WGA). Then two types of affinity adsorption reactions, R-D-SiO(2)-WGA- alkaline phosphatase (ALP) (direct method) and WGA-ALP-WGA-R-D-SiO(2) (sandwich method), are carried out on ACM. The conditions and the analytical characteristics for the determination of ALP using affinity adsorption solid-substrate room temperature phosphorimetry (AA-SS-RTP) were studied. For a 0.40-microl drop of sample, results show that the detection limits of the sandwich method are 0.16 ag spot(-1)(457/622 nm) and 0.17 ag spot(-1)(481/648 nm), and the detection limits of the direct method are 0.41 ag spot(-1) (457/622 nm) and 0.44 ag spot(-1) (481/648 nm). The contents of ALP in human serum correlated well with those obtained by enzyme-linked immunoassay. This study shows that AA-SS-RTP whether by the sandwich method or the direct method, can combine very well the characteristics of both high sensitivity of SS-RTP and specificity of the immunoreaction. Simultaneously, whether the phosphorescence excitation/emission wavelength of either R or D in R-D-SiO(2) is chosen to determine ALP, this can promote the agility and widen the adaptability of AA-SS-RTP.


Asunto(s)
Fosfatasa Alcalina/análisis , Pruebas Diagnósticas de Rutina/métodos , Nanopartículas/química , Rodaminas/química , Coloración y Etiquetado/métodos , Temperatura , Aglutininas del Germen de Trigo/química , Adsorción , Fosfatasa Alcalina/metabolismo , Cromatografía de Afinidad , Humanos , Mediciones Luminiscentes , Ácidos Fosfóricos/análisis , Dióxido de Silicio/química
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