Objective High performance liquid chromatography (HPLC) and liquid chromatography-mass spectrometry (LC/MS) methods were developed for the determination of ganciclovir and its related substances. Methods A Hypersil ODS2 column (4.6mm×250mm, 5μm) was used with a mobile phase of 0.02M potassium 1.0mL/min, and UV detector set at 254nm was used for monitoring the eluents. Results The method was simple, rapid, selective and capable of separating all related substances at trace level with a detection limit of 0.04μg/mL. It has been validated with respect to accuracy, precision, linearity, and limits of detection and quantification. The linearity range was 10.2-153.0μg/mL with r=0.9998. The percentage recoveries ranged from 96.7% to 101.6%, and RSD was 1.24%-1.96% (n=5). Conclusion The method was found to be suitable not only for monitoring the reactions during the process development but also for quality control of ganciclovir. For identification of related substances, LC/MS was used. The mainly related substances of ganciclovir active pharmaceutical ingredients (API) were determined as guanine, (1, 3-dioxolan-4-yl) methyl acetate, and diacetyl guanine.

Euphorbia lathyris （Caper spurge） is a toxic and potent Chinese materia medica （T/PCMM）. This study sought a method for identifying five diterpenoids （Euphorbia factors LI-L3, L7a, and Ls） with the spectra of UV and mass, quantifying three diterpenoids L1, L2, and L8 in crude extracts of unprocessed and processed E. lathyris seeds by liquid chromatography/ electrospray ionization mass spectrometry （LC-ESI-MS）. The analysis was achieved on an Agilent Eclipse XDB-C18 column （4.6 mm× 150mm i.d., 5 μm） with an isocratic elution with a mobile phase consisting of water and acetonitrile at a flow rate of 0.25 mL/min at column temperature of 30 ℃ and UV detection was set at 272 nm. An ESI source was used with a positive ionization mode. The calibration curve was linear in the ranges of 9.9-79 μg/mL for Euphorbia factor Lb 3.8-30.5μg/mL for Euphorbia factor L2, and 1.0-20.6 μg/mL for Euphorbia factor LB. The average recoveries （n=6） of three diterpenoids were 98.39%, 91.10% and 96.94%, respectively, with RSD of 2.5%, 2.4% and 2.1%, respectively. The contents of the three diterpenoids in processed E. lathyris seeds were 3.435, 1.367 and 0.286 mg/g, respectively, which decreased more sharply than those in unprocessed E. lathyris seeds which were 4.915, 1.944 and 0.425 mg/g, respectively. The method is simple, accurate, reliable and reproducible, and it can be applied to control the quality of unprocessed and processed E. lathyris seeds.

OBJECTIVE To investigate the protective effect of total alkaloids of Rhizoma Corydalis (TARC) on experimental gastric mucosal lesions in rats. METHODS Gastric mucosal lesions were induced in rats by injecting acetic acid under gastric mucosal. From the 2nd day post the preparation of the rat model, cimetidine 400 mg · kg-1 or TARC 20, 40 and 80 mg · kg-1 was ig delivered for 15 d in different groups. Two days after the last delivery, gastric juice volume and total acidity were measured. Histopathology of stomach tissues was observed by HE staining. The area of gastric ulcer area was measured and the ulcer index and ulcer inhibitory rate were calculated. The expression of epidermal growth factor (EGF) and EGF receptor (EGFR) was detected by immunohistochemical staining. RESULTS Comparing with shame group, the eare of gastric ulcer and ulcer index were increased signifi?cantly in the model group(P<0.01), suggesting that the model rats were prepared properly. Compared with the model group, the ulcer area in rats of cimetidine and TARC 80 mg·kg-1 groups was decreased by 39.9%and 23.7%,respectively. The ulcer index was decreased by 52.3%and 30.5%,respectively. There was no significant difference between the cimetidine group and TARC 80 mg · kg-1 group, in the ulcer area or index. Compared with model group, EGF protein expression of cimetidine and TARC 40 and 80 mg · kg-1 groups was increased by 81.8%,24.2%and 57.6%,respectively while EGFR protein expression was increased by 45.9%,16.2%and 29.7%,respectively(P<0.05,P<0.01). Deciduous and necrotic gastric mucosal and a large amount of inflmmatory cells infiltration were observed in model group, and gastric mucosal lesions were improved in cimetidine and TARC 40 and 80 mg · kg-1 groups. CONCLUSION TARC has protective effect on gastric mucosal lesions in rats. The mechanism may be related to the increase of EGF and EGFR protein expression.

Euphorbia lathyris (Caper spurge) is a toxic and potent Chinese materia medica (T/PCMM).This study sought a method for identifying five diterpenoids (Euphorbia factors L1-L3,L7a and L8) with the spectra of UV and mass,quantifying three diterpenoids L1,L2,and L8 in crude extracts of unprocessed and processed E.lathyris seeds by liquid chromatography/electrospray ionization mass spectrometry (LC-ESI-MS).The analysis was achieved on an Agilent Eclipse XDB-C18 column (4.6 mm × 150 mm i.d.,5 μm) with an isocratic elution with a mobile phase consisting of water and acetonitrile at a flow rate of 0.25 mL/min at column temperature of 30 ℃ and UV detection was set at 272 nm.An ESI source was used with a positive ionization mode.The calibration curve was linear in the ranges of 9.9-79 μg/mL for Euphorbia factor L1,3.8-30.5 μg/mL for Euphorbia factor L2,and 1.0-20.6 μg/mL for Euphorbia factor L8.The average recoveries (n=6) of three diterpenoids were 98.39％,91.10％ and 96.94％,respectively,with RSD of 2.5％,2.4％ and 2.1％,respectively.The contents of the three diterpenoids in processed E.lathyris seeds were 3.435,1.367 and 0.286 mg/g,respectively,which decreased more sharply than those in unprocessed E.lathyris seeds which were 4.915,1.944 and 0.425 mg/g,respectively.The method is simple,accurate,reliable and reproducible,and it can be applied to control the quality of unprocessed and processed E.lathyris seeds.