ABSTRACT
To verify the interaction between sodium polystyrene sulfonate (SPS) and its concomitant drugs, we elucidated the capability of potassium ions and concomitant drugs to adsorb onto SPS and the effect of their coexistence on the amount adsorbed. We identified 14 drugs used concomitantly with SPS from 2017-2019 in our investigation, and 5 drug preparations used in the clinical setting were used for the experiments. In the artificial intestinal juice, SPS adsorbed 39.05-69.77 mEq/g of potassium ions. Amlodipine besylate and nifedipine were well-adsorbed, while azosemide and febuxostat were did not adsorb well onto SPS. Our results and the results of a previous study suggest that additives in drug preparations affect the adsorption of drugs onto SPS. The adsorption kinetics onto SPS of drugs conformed to the pseudo-second order model. However, the adsorption of amlodipine besylate completely may not be fitted to the pseudo-second order model. The amount of amlodipine besylate adsorbed under the coexistence of potassium ions decreased compared to when potassium ions were absent. The amount of nifedipine and potassium ions adsorbed remained constant, regardless of whether potassium ions were present or not. These results might be due to the differences in their mechanisms of adsorption onto SPS and to the characteristics of the drugs. In a clinical setting, SPS is used concomitantly with various oral drugs. The interaction between SPS and its other concomitant drugs need to be elucidated more to obtain enough evidence for pharmacists to propose the appropriate prescription.
Subject(s)
Nifedipine , Potassium , Adsorption , Ions , Gastrointestinal Tract , AmlodipineABSTRACT
ABSTRACT OBJECTIVE：To study the metabolic transformation of total glycosides of Cistanche deserticola in artificial gastric and intestinal juice，and to speculate its metabolic transformation pathway in vivo. METHODS：UPLC/Q-TOF-MS was adopted. The determination was performed on ACQUITY UPLC BEH column with mobile phase consisted of 0.2％ formic acid water-acetonitrile（gradient elution）at the flow rate of 0.2 mL/min. The detection wavelength was set at 330 nm，and column temperature was 25 ℃. The ion source was electrospray ion source，and mass to charge ratio（m/z）was 50→1 000. In the positive and negative ion mode，the metabolic components of the total glycosides of C. deserticola in artificial gastric and intestinal juice were identified analysis，and combined with the literature，the metabolic pathway of total glycosides of C. deserticola in artificial gastric and intestinal juice was speculated. RESULTS：After the total glycosides of C. deserticola were metabolized by artificial gastric juice，and a total of 69 components were estimated，including 14 prototype components （such as Mustard aldehyde glucoside，daucosstorol） and 55 metabolic components （such as Methyl-O-Kankanoside J，Methyl-O-Kankanoside E），it is speculated that its metabolic pathways were methylation，demethylation，hydroxylation，methoxylation，acetylation，sulfation，and glucuronidation. After the total glycosides of C. deserticola were metabolized by artificial intestinal juice，a total of 90 components were estimated，including 4 prototype components（such as Kankanoside M，Kankanoside L）and 86 metabolic components（such as Methyl-O-Kankanoside， Methyl-O-Kankanoside E）. It was speculated that its metabolic pathways were methylation， demethylation，hydroxylation，dehydroxylation，methoxylation，acetylation，sulfation and glucuronidation. CONCLUSIONS：This study preliminarily speculates that the total glycosides of C. deserticola may be metabolized by methylation，demethylation， hydroxylation and other metabolic pathway in artificial gastrointestinal juice，which may provide reference for the in vivo metabolic transformation of total glycosides of C. deserticola.
ABSTRACT
OBJECTIVE:To study the ex vivo adsorption of montmorillonite powder to ofloxacin.METHODS:Different dosages of ofloxacin and montmorillonite powder were mixed with artificial gastric juice and artificial intestinal juice,respec?tively,which were filtrated after warmed at(37?0.5)℃in water bath for1hour,the content changes of ofloxacin were de?termined by ultraviolet spectrometry.RESULTS:The adsorption rates of montmorillonite powder to ofloxacin in artificial gastric juice and in artificial intestinal juice were(99.76?0.01)%and(99.55?0.02)%,respectively.CONCLUSIONS:Montmorillonite powder has strong adsorption to ofloxacin in both artificial gastric juice and artificial intestinal juice,there?fore,which should not be administered simultaneously in the clinic.
ABSTRACT
This paper is to study the stability of recombinant human epidermal growth factor (rhEGF) in artificial intestinal juice and gastric juice,providing references for its clinical application in intestinal and stomach injury.RhEGF was added into artificial intestinal juice and gastric juice respectively, and the content of rhEGF was determined with RIA at preset time points. The content of rhEGF in artificial gastric juice (pH 2) and intestinal juice (pH 6.8) had a tendency to decrease as time went by,reaching 43.46% and 21.91% from their baselines 1 h later respectively. But the decrease of rhEGF reached 89.62% and 79.52% 1 h after the presence of peptic enzymes respectively. The rhEGF in the artificial intestinal juice and gastric juice was relatively stable but the process of its inactivation could be greatly expedited in the presence of peptic enzymes.
