Application of a HPLC-Q/TOF method with post-column compensation for separation and identification of polar impurities in Cytidine disodium triphosphate for injection

Background: Cytidine Disodium Triphosphate (CTP-2Na) for injection is mainly used for treating nervous system diseases. Currently, there are few studies focused on the separation and identification of polar impurities in CTP-2Na for injection, which is important for ensuring drug safety and efficacy. Objective: The study aimed to establish an HPLC-Q/TOF method for the separation and identification of polar impurities in CTP-2Na for injection. Methods: Chromatographic separation was achieved on a Waters Atlantis T3 column using 5 mM aqueous ammonium acetate solution as the mobile phase in an isocratic elution mode. A postcolumn compensation technology was used to improve the ionization efficiency of impurities in the spray chamber. Results: Three polar impurities (disodium cytidine tetraphosphate, disodium cytidine diphosphate, disodium cytidine monophosphate) were detected in CTP-2Na for injection. The former one is probably the overreaction product during the production of CTP-2Na, the latter two were reported as degradation products. The fragmentation patterns of cytidine phosphate compounds in negative ion mode are summarized. Conclusion: This study provides a good reference for the separation and identification of polar impurities in nucleotide drugs.

An Improved LC-MS/MS Method for Simultaneous Determination of the Eleven Bioactive Constituents for Quality Control of Radix Angelicae Pubescentis and Its Related Preparations

An improved LC-MS/MS method was developed for simultaneous determination of eleven bioactive constituents of Radix Angelicae Pubescentis and its related preparations. It was the first report on the quantification of bioactive constituents in different preparations of Radix Angelicae Pubescentis by LC-MS/MS analytical method. These samples were separated with an Agilent Zorbax Extend reversed-phase C18 column (1.8 μm, 4.6 × 100 mm) by linear gradient elution using aqueous ammonium acetate and acetonitrile as mobile phase. The flow rate was 0.3 mL min−1. The eleven bioactive constituents showed good regression(R>0.990)within test ranges and the recoveries were in the range of 87.1–110%. The limit of detections and quantifications for most of the major constituents were less than 0.5 and 1.0 ng mL−1, respectively. All results indicated that the developed method could be readily utilized as a suitable quality control method for Radix Angelicae Pubescentis and related preparations.

High Pressure Liquid Chromatographic Separation and Quantisation of Chlordiazepoxide. HC1 and Two of Its Related Compounds

A method is described for the separation and quantitative determination of chlordiazepoxide. HC1 and 2 related compounds, 7-chloro-l-3-dihydro-5-phenyl-2H-1, 4-benzodiazepin-2-one-4-oxide (CBO) and 2-amino-5-chIorobenzophenone (ACB), by high pressure liquid chromatography. The 3 compounds are separated on a reverse phase microparticulate column packing, using a mobile phase of acetonitrile and aqueous ammonium acetate. Bulk powders or capsule formulations are quantitated by direct comparison of their peak heights to those of appropriate reference standards. Data are presented showing the limit of detectability for the related compounds to be less than 80 ng CBO/ml and less than 40 ng ACB /ml. Based on peak heights, the relative standard deviation for the precision for chlordiazepoxide. HC1 is 0.42%. Recoveries from laboratory-prepared samples for chlordiazepoxide. HC1 were 99.4%; CBO, 102.4%; and ACB, 99.7%.

On a new form of reagent against perspiration effects on shoe materials

In a discussion of a series of tests connected with the fastness of colours on textile fibres, Villavecchia (1918) mentions the use of neutral ammonium acetate or common salt solution for measuring the colour resistance to perspiration. Thus in the case of coloured cotton, this is immersed for 10 min. alongside an equal quantity of white cotton yarn in a 0·1% aqueous ammonium acetate at 80°C., and the extent of colouring of the yarn as well as the degree of stripping of the coloured sample noted after drying without rinsing. An odd number of degrees of fastness is arbitrarily assigned to the coloured specimen according to the result, e.g. V degrees if neither the original tint nor the whiteness of the yarn is changed. Similarly with linen, hemp and ramie. For coloured wool both methods are used, viz. with sodium chloride and with ammonium acetate. In the former case, the alteration in colour is noted after simply dipping the wool in salt solution and allowing to air-dry out at room temperature. In the latter case, an equal quantity of white zephyr wool in addition to the white cotton is present. V degrees in all cases are stated to be conventionally adopted between industrial associations and dyestuff manufacturers for materials which are fast enough to reveal no change whatever in the testing bath. For coloured silk there are no precise data, and usually it is immersed in distilled water for several days to ascertain if any colour is lost.