16 research outputs found
Improved functionalization of oleic acid-coated iron oxide nanoparticles for biomedical applications
Superparamagnetic iron oxide nanoparticles
can providemultiple benefits for biomedical applications
in aqueous environments such asmagnetic separation or
magnetic resonance imaging. To increase the colloidal
stability and allow subsequent reactions, the introduction
of hydrophilic functional groups onto the particlesâ
surface is essential. During this process, the original
coating is exchanged by preferably covalently bonded
ligands such as trialkoxysilanes. The duration of the
silane exchange reaction, which commonly takes more
than 24 h, is an important drawback for this approach. In
this paper, we present a novel method, which introduces
ultrasonication as an energy source to dramatically
accelerate this process, resulting in high-quality waterdispersible nanoparticles around 10 nmin size. To prove
the generic character, different functional groups were
introduced on the surface including polyethylene glycol
chains, carboxylic acid, amine, and thiol groups. Their
colloidal stability in various aqueous buffer solutions as
well as human plasma and serum was investigated to
allow implementation in biomedical and sensing
applications.status: publishe
Safety and pharmacokinetics of repeat-dose micafungin in young infants
Due to the risk of central nervous system infection, relatively high weight-based echinocandin dosages may be required for successful treatment of invasive candidiasis and candidemia in young infants. This open-label study assessed safety and pharmacokinetics of micafungin in 13 young infants (> 48 hours of age and < 120 days of life) with suspected candidemia or invasive candidiasis. Infants weighing â„ 1,000 g and < 1,000 g received 7 and 10 mg/kg/day, respectively, for a minimum of 4 to 5 days. Mean baseline weight and gestational age were 2101 g and 688 g, and 30 weeks and 25 weeks, in the 7 and 10 mg/kg/day groups, respectively. Median pharmacokinetic values for the 7 and 10 mg/kg/day groups, respectively, were: AUC(0â24), 258.1 and 291.2 ÎŒgâąh/ml; Cl(ss/wt,) 0.45 and 0.57 ml/min/kg; C(max,) 23.3 and 24.9 ÎŒg/ml; and Vd(ss/wt,) 341.4 and 542.8 ml/kg. No deaths or discontinuations from treatment occurred. These data suggest that micafungin dosages of 7 and 10 mg/kg/day were well tolerated and provided exposure that was demonstrated in animal model to be adequate for central nervous system coverage