Elucidating the in vivo fate of pharmaceutical excipient sodium carboxymethylcellulose in rats using UHPLC- Q TRAP MS/MS and UHPLC- Q TOF MS/MS approach

Aim Sodium carboxymethylcellulose acts as both a pharmaceutical excipient (interacting with drugs to affect metabolism) and an active substance (stimulating intestinal peristalsis via aqueous polymeric colloids). To clarify its in vivo fate and advance sodium carboxymethylcellulose-based adjuvant delivery, a targeted analysis was needed, using dextromethorphan hydrobromide as a model drug.Research design and method A comprehensive LC-MS approach was established: UHPLC-Q TRAP MS/MS (quantitative) and HPLC-Q TOF MS/MS (qualitative) were used to study sodium carboxymethylcellulose pharmacokinetics, distribution, metabolism, and excretion in male Wistar rats, with/without co-administered dextromethorphan hydrobromide.Results The distribution of sodium carboxymethylcellulose is expedited to organs characterized by augmented blood flow velocities, including the spleen, liver, and heart. And about 66.4% sodium carboxymethyl cellulose was removed from plasma within 36 h. Results also showed that the excretion level of sodium carboxymethyl cellulose is less than the dosage administered, and almost all glycosidic bonds had been hydrolyzed in its process.Conclusion The findings provide complete description of sodium carboxymethylcellulose in vivo fate, establishing a novel framework that facilitates the extensive utilization of this pharmaceutical excipient in the process of drug formulation development.