Application of high-performance thin layer chromatography and near infrared spectroscopy in the validation of in-use stability of herbal medicines used in the management of Covid-19

Abstract

Stability testing is a requirement in the registration process for all medicinal products, including herbal medicinal products (HMPs). This study was designed to investigate the stability of two herbal liquid preparations, Covidol^® and Rona^®, used to treat Covid-19 in Tanzania. The study aimed to predict the effect of standard environmental conditions on the in-use stability of liquid formulations of Covidol^® and Rona^® stored at ambient conditions for 28 days after opening. The chemical stability patterns of the two products were monitored using high-performance thin layer chromatography (HPTLC) and near infrared spectroscopy (NIRS) methods. Physical parameters such as pH, appearance and odor were also monitored. Under ambient conditions, Covidol^® remained stable throughout the study period while Rona^® underwent degradation as indicated by changes in its HPTLC and NIRS fingerprint patterns. These methods can be applied for quality control and stability testing of Covidol® and Rona^® herbal products.