Identification and quality control strategy of impurities in Zhengqing Fengtongning injection.

Zhengqing Fengtongning injection is the sterile aqueous solution of Sinomenine Hydrochloride extracted from the root and stem of Sinomenium acutum, and is widely used to treat rheumatoid arthritis. Due to the processes of extraction, separation, purification, preparation and storage, some related impurities might be formed, which may cause side effects on patients. It is important to rapidly separate and identify the related impurities to ensure the safe use of Zhengqing Fengtongning injection. However, there are few literatures about the impurity in Zhengqing Fengtongning injection. In this work, ultra-high performance liquid chromatography- quadrupole time-of-flight mass spectrometry (UPLC-QTOF/MS) was developed to analyze impurities in both Zhengqing Fengtongning injection and its drug substance, with Sinomenine Hydrochloride as its active pharmaceutical ingredient (API). Six impurities of the Zhengqing Fengtongning injection were found. Structures of impurities 1 and 6 were confirmed by NMR and other impurities were identified from the fragmentation pattern of Sinomenine, the similarity of molecular weight and fragment ions in references. Finally, the HPLC analytical technique was developed to achieve the quantification of impurities 1 and 6. In addition, some reasonable suggestions are put forward on the quality control of Zhengqing Fengtongning injection and its drug substance based on the processes and structural characteristics of the related substances. The technical system established in this paper is helpful to strengthen the quality control of Zhengqing Fengtongning injection and improve production, and can also provide references for the production and quality control of similar drugs.

p33ING1b methylation in fecal DNA as a molecular screening tool for colorectal cancer and precancerous lesions.

The present study aimed to investigate the feasibility of detecting p33 inhibitor of growth 1b (p33ING1b) gene methylation in fecal DNA as a screening method for colorectal carcinoma (CRC) and precancerous lesions. The methylation of p33ING1b was analyzed in fecal samples from 61 patients with CRCs, 27 patients with precancerous lesions (advanced adenoma) and 20 normal individuals by nested methylation-specific polymerase chain reaction (nMSP) and fecal occult blood test. Methylated p33ING1b was detected in 73.77% of CRC patients and 62.96% of adenoma patients. By contrast, only 5% of normal individuals had methylated p33ING1b. These results indicated 73.77% sensitivity for detecting CRC, 62.96% sensitivity for detecting precancerous lesions and 95% specificity of the assay for detecting CRCs and precancerous lesions. The detection of p33ING1b methylation status by incubation of DNA contained in agarose beads for bisulfite modification, followed by nMSP, is a promising non-invasive screening method for CRCs and precancerous lesions.