Publications by authors named "Karen Ying Kwok"

This paper describes the detections of nonsteroidal and steroidal selective androgen receptor modulators (SARMs), namely, RAD140 and YK-11, in mane hair collected from horses having been orally administered with the respective drugs. SARMs are potent anabolic agents with a high potential of misuse in horseracing and equestrian sports, and the misuses of RAD140 and YK-11 in human sports have been reported. To better control the misuse of RAD140 and YK-11 in horses, two separate oral administration studies of RAD140 (0.

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Organophosphate flame retardants are ubiquitous environmental contaminants; however, knowledge is limited regarding their environmental health risks and toxicity. Here, we investigated the effects of acute and long-term exposure to tris(1,3-dichloro-2-propyl) phosphate (TDCPP) to the nervous system of zebrafish. Zebrafish embryos (2 h post-fertilization) were exposed to TDCPP (0-100 μg/L) for 6 months up until sexual maturation.

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A new class of luminescent biotinylation reagents derived from cyclometalated iridium(III) and rhodium(III) bis(pyridylbenzaldehyde) biotin complexes, [Ir(pba)(2)(bpy-C6-biotin)](PF(6)) (1), [Ir(pba)(2)(bpy-TEG-biotin)](PF(6)) (2), and [Rh(pba)(2)(bpy-C6-biotin)](PF(6)) (3), together with their biotin-free counterparts [Ir(pba)(2)(bpy-Et)](PF(6)) (4) and [Rh(pba)(2)(bpy-Et)](PF(6)) (5) [Hpba = 4-(2-pyridyl)benzaldehyde, bpy-C6-biotin = 4-[(6-biotinamido)hexylaminocarbonyl]-4'-methyl-2,2'-bipyridine, bpy-TEG-biotin = 4-[(13-biotinamido-4,7,10-trioxa)tridecylaminocarbonyl]-4'-methyl-2,2'-bipyridine, bpy-Et = 4-(ethylaminocarbonyl)-4'-methyl-2,2'-bipyridine], have been synthesized and characterized and their photophysical and electrochemical properties studied. Upon photoexcitation, the iridium(III) complexes 1, 2, and 4 exhibited intense and long-lived orange-yellow luminescence in fluid solutions at 298 K and in rigid glass at 77 K. The rhodium(III) complexes 3 and 5 were weakly emissive in fluid solutions at 298 K but showed intense luminescence in low-temperature glass.

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Article Synopsis
  • A series of luminescent iridium(III) conjugates, designed by linking bipyridine with estradiol derivatives, were synthesized and characterized for their properties.
  • Upon excitation, these complexes emitted bright and long-lasting light in various conditions, with specific emission types identified indicating their photophysical behaviors.
  • When tested for binding with the estrogen receptor alpha, the conjugates showed increased emission intensity and longer lifetimes, positioning them as innovative fluorescent probes for studying this receptor.
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