Process Development and Scale-Up of a Novel Atypical DAT Inhibitor (S)-CE-123.

Large-scale syntheses of small molecules and kilo laboratories are crucial steps in drug development, especially in advanced stages. (S)-5-((Benzhydrylsulfinyl)methyl)thiazole, (S)-CE-123, a potent, selective, and novel atypical DAT inhibitor, has undergone iterative testing as part of the preclinical evaluation step. This required the process transfer, scale-up, and synthesis of a 1 kg preclinical batch. The Kagan protocol for asymmetric sulfide to sulfoxide oxidation was successfully applied within a four-step synthetic process for the successful upscaling of (S)-CE-123. During the scale-up of the last step, several changes were made to the original synthetic procedure, as with every increase in batch size, new problems had to be overcome. These include, among others, the workup optimization of the last step, the simplification of chromatographic purification, elution modification to improve the purity of the product and saving of workup time. Two washing steps were added to the original procedure to enhance both the yield and the enantiomeric excess value of the final product. The modifications introduced allowed access to a 1 kg (S)-CE-123 batch with a purity >99% and an enantiomeric excess value of 95%.

Validation of the R-Biopharm AG RIDASCREEN® Histamine (Enzymatic) Kit.

BACKGROUND: RIDASCREEN® Histamine (enzymatic) is an enzymatic test kit for quantification of histamine in fresh fish, canned fish, fish meal, cheese, and wine. METHODS: Fish products are extracted with boiling water, while cheese is extracted with water, and the extract is treated with perchloric acid/potassium hydroxyde. Wine is extracted with the reagents of RIDA® Sample Decolorant kit to eliminate color pigments and interfering compounds. The enzymatic determination is based on histamine dehydrogenase, which catalyzes the oxidative deamidation of histamine in the presence of an electron carrier that converts a dye to a color product. The resulting color intensity is directly proportional to histamine concentration and is measured at 450 nm. The substrates are coated on the microtiter plate. RESULTS: The linear range is from 1 to 20 mg/L in the extract. LOQs are 2 mg/kg for fresh fish, canned fish, and cheese, 1.4 mg/L in wine, and 10 mg/kg for fish meal. The linear range is from 5 to 100 mg/kg for fish products and cheese, 3.6 to 72 mg/L for wine, and 25 to 500 mg/kg for fish meal. Recovery and precision are very good for all matrices, and comparisons with HPLC reference methods revealed that the method also delivers true results for fish products and wine. Agmatine shows a low side activity of around 0.75% at 10 g/kg. Possible interfering substances are ascorbic acid (more than 250 mg/L in wine or 250 mg/kg in fish). A special sample preparation to deplete ascorbic acid from fresh fish is described.

Validation study of a commercial aflatoxin detection kit according to the notification method in Japan.

A commercial aflatoxin detection ELISA kit, "RIDASCREEN(®) FAST Aflatoxin", was validated with corn samples naturally contaminated with aflatoxin and non-contaminated reference corn samples according to the Japanese Notification Method ShokuAnHatsu 0816-7. The trueness, intra-laboratory repeatability, intermediate precision, limit of detection and limit of quantitation were found to be 91%, 10%, 6.4%, 0.6µg/kg and 2µg/kg, respectively, and the performance of the kit was recognized as complying with all criteria in the Supplement Table of the Notification. These data suggest that this kit is useful as a simplified device to screen out negative corn samples contaminated with less than 4µg/kg.

Identification and quantification of fungi and mycotoxins from Pu-erh tea.

Pu-erh tea originates from the province of Yunnan in south-western China. As this tea is produced by so called Aspergillus post-fermentation the question arises which molds and mycotoxins may be found in this tea. In total 36 samples of Pu-erh tea were investigated for their content of filamentous fungi and the mycotoxins aflatoxins B1, B2, G1, and G2, fumonisins B1, B2, and B3, and ochratoxin A. Fungi were isolated from all samples in a concentration of 1.0×10(1) to 2.6×10(6) colony forming units (cfu)/g tea, all together 19 fungal genera and 31 species were identified. The most prevalent species were Aspergillus acidus and Aspergillus fumigatus, followed by Zygomycetes and Penicillium species. Aflatoxins and fumonisins were not found in the samples investigated, ochratoxin A was detected in 4 of 36 teas (11.1%).