Long‐Term Oral Carbocisteine Therapy in Patients with Chronic Bronchitis. A Double Blind Trial with Placebo Control

A rapid and sensitive liquid chromatography/tandem mass spectrometry (LC/MS/MS) method to determine carbocysteine in human plasma was developed and fully validated. After methanol-induced protein precipitation of the plasma samples, carbocysteine was subjected to LC/MS/MS analysis using electrospray ionization (ESI). The MS system was operated in the selected ion monitoring (SRM) mode. Chromatographic separation was performed on a Hypurity C18 column (i.d. 2.1 mm x 50 mm, particle size 5 microm). The method had a chromatographic running time of 2.0 min and linear calibration curves over the concentration ranges of 0.1-20 microg/mL for carbocysteine. The lower limit of quantification (LLOQ) of the method was 0.1 microg/mL for carbocysteine. The intra- and inter-day precision was less than 7% for all quality control samples at concentrations of 0.5, 2.0, and 10.0 microg/mL. These results indicate that the method was efficient with a simple preparation procedure and a very short running time (2.0 min) for carbocysteine compared with methods reported in the literature and had high selectivity, acceptable accuracy, precision and sensitivity. The validated LC/MS/MS method has been successfully used to a bioequivalence study of two tablet formulations of carbocysteine in healthy volunteers.

show abstract

Determination of carbocysteine in human plasma by liquid chromatography/tandem mass spectrometry employing precolumn derivatization

Chen

Zhong

Han

et al. 2002

Rapid Comm Mass Spectrometry

View full text Add to dashboard Cite

A sensitive liquid chromatography/tandem mass spectrometry (LC/MS/MS) method was developed to determine carbocysteine in human plasma using 2-pyridylacetic acid as the internal standard (IS). The method employed derivatization with 10 M hydrochloric acid/methanol, which significantly improved the ionization efficiency of carbocysteine. After methanol-induced protein precipitation of plasma samples, carbocysteine and the IS were derivatized and subjected to LC/MS/MS analysis using atmospheric pressure chemical ionization. The method has a lower limit of quantitation of 20 ng/mL for a 0.2-mL plasma aliquot. The intra- and inter-day precision (RSD), calculated from quality control (QC) samples, was less than 7%. The accuracy, determined using QC samples, was within +/- 1%. The method offered increased sensitivity, selectivity and speed of analysis over existing methods. The method was utilized to support clinical pharmacokinetic studies of carbocysteine in volunteers following oral administration.

show abstract

scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.

Contact Info

hi@scite.ai

10624 S. Eastern Ave., Ste. A-614

Henderson, NV 89052, USA

Blog Terms and Conditions API Terms Privacy Policy Contact Cookie Preferences Do Not Sell or Share My Personal Information

Made with 💙 for researchers

Part of the Research Solutions Family.

Long‐Term Oral Carbocisteine Therapy in Patients with Chronic Bronchitis. A Double Blind Trial with Placebo Control

Cited by 17 publications

References 4 publications

Mucolytic agents versus placebo for chronic bronchitis or chronic obstructive pulmonary disease

Mucolytic agents versus placebo for chronic bronchitis or chronic obstructive pulmonary disease

High‐throughput determination of carbocysteine in human plasma by liquid chromatography/tandem mass spectrometry: application to a bioequivalence study of two formulations in healthy volunteers

Determination of carbocysteine in human plasma by liquid chromatography/tandem mass spectrometry employing precolumn derivatization

Contact Info

Product

Resources

About