Preparation of hydrophobic and hydrophilic albumin microspheres and determination of surface carboxylic acid and amino residues

1997 ◽  
Vol 151 (1) ◽  
pp. 47-55 ◽  
Author(s):  
A.B. MacAdam ◽  
Z.B. Shafi ◽  
S.L. James ◽  
C. Marriott ◽  
G.P. Martin
2016 ◽  
Vol 2016 ◽  
pp. 1-8 ◽  
Author(s):  
G. O. Bosire ◽  
J. C. Ngila ◽  
H. Parshotam

The extraction and determination of aliphatic and aromatic carboxylic acids as well as their influence on the aromaticity and molecularity relationship of natural organic matter (NOM) in water are reported in this study. Three solid phase extraction (SPE) sorbents were used and their extraction efficiencies evaluated after chromatographic determinations (using gas chromatography with a time of flight mass spectrometer (GC × GC-TOFMS) and liquid chromatography with organic carbon detector (LC-OCD)). More than 42 carboxylic acids were identified in raw water from the Vaal River, which feeds the Lethabo Power Generation Station, South Africa, with cooling water. The aromatic carboxylic acid efficiency (28%) was achieved by using Strata™X SPE while the highest aliphatic carboxylic acid efficiency (92.08%) was achieved by silica SPE. The hydrophobic nature of NOM in water depends on the nature of organic compounds in water, whether aromatic or aliphatic. The LC-OCD was used to assess the hydrophobicity levels of NOM as a function of these carboxylic acids in cooling water. The LC-OCD results showed that the aromatic nature of NOM in SPE filtered water followed the order Silica>Strata X>C-18. From the results, the hydrophobicity degree of the samples depended on the type and number of carboxylic acids that were removed by the SPE cartridges.


Author(s):  
Yan Xiong ◽  
Yong-Hong Liu ◽  
Jian-Sha Li ◽  
Yu-Ying Zhang ◽  
Jing Zhang ◽  
...  

Abstract A simple high performance liquid chromatography (HPLC) method was developed and validated for the determination of coumarin-3-carboxylic acid analogues (C3AA) in rat plasma and a preliminary study on pharmacokinetics. Ferulic acid (FA) was used as the internal standard substance, and coumarin-3-carboxylic acid (C3A) was used as a substitute for quantitative C3AA. After protein precipitation with methanol, the satisfactory separation was achieved on an ODS2 column when the temperature was maintained at 30 ± 2°C. The correlation coefficient r in the C3A linear equation is equal to 0.9990. Pharmacokinetic parameters for t1/2, Tmax, Cmax, area under the curve (AUC)0-t, average residence time (MRT), apparent volume of distribution (V z/F) and clearance (Cl/F) were 1.89 ± 0.03 h, 0.39 ± 0.14 h, 1.81 ± 0.10 g· mL−1 ·h, 7.88 ± 0.24 g·mL−1·h, 3.23 ± 0.14 h, 0.43 ± 0.03 (mg·kg−1)·(g·mL−1)−1·h−1, respectively. The high performance liquid chromatography-photo diode array detector (HPLC-PDA) method established in this study can be used to separate and determine the content of C3AA in plasma of rats after 60% ethanol extraction by gavage. The plasma concentration-time curve and pharmacokinetic parameters reflect the absorption of C3AA in rat blood after oral administration to some extent.


Sign in / Sign up

Export Citation Format

Share Document