Determination of Salt Forms of New Psychoactive Substances by Ion Chromatography / 法医学杂志

Objective To establish an ion chromatography method for the salt form determination of new psychoactive substances （NPS）. Methods The method of conducting qualitative and quantitative analysis of six types of organic acid ions （acetate ion, tartrate ion, maleate ion, oxalate ion, fumarate ion, citrate ion） and five types of inorganic anions （fluoride ion, chloride ion, nitrate ion, sulfate ion, phosphate ion） in NPS sample by ion chromatography was developed. The salt forms of 222 seized NPS samples （103 samples with synthetic cannabinoids, 81 samples with cathinones, 44 samples with phenylethylamines, 12 samples with tryptamines, 7 samples with phencyclidines, 6 samples with piperazines, 2 samples with aminoindenes, 26 samples with fentanyls and 43 samples with other types of NPS） were analyzed by this method. Results Each anion had good linearity in the corresponding linear range, the correlation coefficients （r） were greater than 0.999, the limits of detection were 0.01-0.05 mg/L, and the limits of quantitative were 0.1-0.5 mg/L. Except that 5F-BEPIRAPIM was hydrochloride, the salt forms of the other 102 synthetic cannabinoids were all base. The salt form of 81 cathinone samples, 44 phenylethylamine samples, 7 phencyclidine samples and 2 aminoindene samples were all hydrochloride. The salt forms of tryptamine samples included base, hydrochloride, fumarate and oxalate. The salt forms of piperazine samples included base and hydrochloride. The salt forms of fentanyl samples and samples of other types included base, hydrochloride and citrate. Conclusion Ion chromatography is a simple, accurate and efficient method for determining the salt form of NPS samples, which makes the qualitative and quantitative conclusions of NPS more scientific and rigorous.

Preparation of human transferrin and verification of the antigenic activity / 国际检验医学杂志

Objective Non-affinity methods were used to purify transferrin(TRF)with high purity from human serum,and the immunogenicity of TRF was evaluated by immunizing New Zealand rabbits.Methods Firstly,TRF was extracted from serum by precipitation with ammonium sulfate and then purified by two-step anion exchange chromatography.Results SDS-PAGE purity of the prepared TRF was similar with the control pure product,and the HPLC purity reached to 96.8% with a yield of 78.6%.For the same batch of TRF sam-ple,the ratio between the activity concentration determinated using TRF kit(immunoturbidimetry method) and the protein concentration determinated using uv-spectrophotometric method was about 0.95,which indica-ted that the prepared TRF for antigen could react well with the TRF antibody included in the TRF kit.Final-ly,New Zealand rabbits were immunized using the purified TRF,and the titer of the rabbit anti-serum could reach 1:128 000 after four time immunization,which also indicated that the prepared TRF had good immuno-genicity.Conclusion The TRF with high purity had good antigen reactivity and immunogenicity to prepare anti-T RF antibody by immunizing rabbits,w hich could provide qualified materials for the production of T RF kit(immunoturbidimetry method).

Monosaccharide Composition Analysis of Arabinoxylan by High Performance Anion Exchange Chromatography with Pulsed Amperometric Detection / 分析化学

A method of complete acid hydrolysis combined with high performance anion exchange chromatography and pulsed amperometric detection was developed for the monosaccharide composition analysis of arabinoxylan from the seeds of Plantago asiatica L. The parameters including hydrolysis methods, acid types, acid concentration, hydrolysis temperature, hydrolysis time and placement time, which would affect the hydrolysis process, were optimized. The results showed that it would have a better hydrolysis effect for polysaccharide from the seeds of Plantago asiatica L. with 2 mol/L H2 SO4 in an atmospheric oil bath at 120℃for 2 hours. However, the placement time for diluted solution of the hydrolyzed polysaccharide should be less than 6 hours. The polysaccharide was mainly composed of Arabinose (8. 89%) and Xylose (41. 52%) and Galacturonic acid (0. 73%). Glcuronic acid (3. 44%) was detected simultaneously, and there were also trace amounts of Galatose and Glucose. The results were reproducible. Other arabinoxylans from Panicummiliaceum L. shell, Avena sativa L. bran and Hordeum vulgare L. were taken for monosaccharide compositions analysis under the optimal hydrolysis conditions and the analysis results were good. This study would provide a good reference for monosaccharides composition analysis of arabinoxylans from various sources.

Monosaccharide composition analysis on polysaccharides in Polygonatum cyrtonema by high performance anion-exchange chromatography with pulsed amperometric detection / 中草药

Objective: To develop a method for determination of monosaccharide composition of Polygonatum cyrtonema polysaccharides (PCR) by high performance anion-exchange chromatography with pulsed amperometric detection (HPAEC- PAD). Methods: The water-soluble crude polysaccharides were extracted from the P. cyrtonema Hua, then the polysaccharides were hydrolyzed with sulfuric acid, then separated by CarboPac PA1 column (250 mm × 4 mm, 10.0 μm) and with gradient elution, determination of monosaccharide composition in PCP by HPAEC-PAD. Results: The results showed that within the range of 1-100 mg/L it has good linearity (r > 0.999), The detection limitation was 0.015-0.025 mg/L, 1.35%-2.80% RSD, the recovery rates were 88.36%-111.3%. The results showed that the polysaccharides in P. cyrtonema Hua from different regions were composed of rhamnose, arabinose, galactose, glucose, mannose, and fructose. Conclusion: The proposed method has good separation effect and high sensitivity, which can be used for the study on monosaccharide composition and content determination of PCP.

Comparison of fast protein liquid chromatography (FPLC) with HPLC, electrophoresis & microcolumn chromatography techniques for the diagnosis of β-thalassaemia.

Background & objectives: β-thalassaemia is a genetic disorder and an important health problem around the world. Quantitative haemoglobin A2 (HbA2) levels are used for the diagnosis of β-thalassaemia. The conventional methods are high performance liquid chromatography (HPLC), electrophoresis, and microcolumn chromatography techniques. We established a fast protein liquid chromatography (FPLC) method, to measure quantitatively of HbA2 levels, and compared its efficacy with conventional methods. Methods: The FPLC method, using a DEAE Sepharose, Hi Trap anion-exchange column chromatography technique was set up for HbA2 measurement. In this study, 220 blood samples were screened for haemoglobin type by FPLC technique and also using HPLC, microcolumn chromatography and electrophoresis. Results: The FPLC results were highly correlated (r = 0.985, P<0.001) with those of HPLC for quantification of HbA2 as well as cellulose acetate electrophoresis (r = 0.977) and microcolumn chromatography (r = 0.980). The FPLC method showed 100 per cent sensitivity and specificity, positive and negative predictive value for β-thalassaemia diagnosis. In addition, the FPLC method was simple, rapid, low cost and reproducible. The HbA2/E range of FPLC for β-thalassaemia was 6-10 per cent, HbE trait was 10-40 per cent, β-thalassaemia/HbE was 40-60 per cent and homozygous HbE was more than 60 per cent. Interpretation & conclusions: Our findings suggested that FPLC method could be used as a cost-effective method for routine β-thalassaemia diagnosis.

Two-step Tandem Chromatography Purification of Anti-human CD80 Monoclonal Antibody 4E5 from Mouse Ascites / 中国生物工程杂志

A two-step method for the purification of blocking-type anti-human CD80 monoclonal antibody 4E5 from mouse ascites was developed using anion exchange and gel filtration in combination. The ascites was first purified by anion exchange after centrifugation and filtration. The experimental parameters of sample loading and elution were optimized. The optimized loading condition was pH 8.0,50 mmol/L Tris-HCl and satisfactory results were obtained using a 0~0.5mol/L NaCl step elution. The fraction containing the protein of interest was directly loaded on gel filtration column and eluted using a 20 mmol/L phosphate buffer at pH 7.2. The purity of the obtained monoclonal antibody was up to 95% with a recovery of 61%. The purity of mAb could efficiently inhibit the growth of Daudi cells. The amplification of the method was also studied using a Bio-Scale Q5 column and the result was satisfied.