BACKGROUND: We evaluated the performance of the TOSOH glycohemoglobin analyzer HLC-723GHb V A1c 2.2TM (TOSOH Corp. Kyoto, Japan), a recently introduced automated hemoglobin A1c (HbA1c) analyzer using high performance liquid chromatography (HPLC) method without sample pretreatment. METHODS: The performance characteristics evaluated were precision, linearity, comparison with VARIANTTM (Bio-Rad, Germany) and throughput following NCCLS evaluation protocols (EP5-T2, EP6-P, and EP9-T). RESULTS: The within-run and between-day CV's were 0.910 and 1.328 for low level (6.2%), 1.214 and 1.460 for middle level (8.5%), and 0.789 and 1.449 for high level (10.7%), respectively. We found the perfect linearity of HbA1c (%) from 6.5 to 10.2 (r2=0.9995). Comparison studies between A1c 2.2 and VARIANTTM yielded the following correlation equations; A1c 2.2TM = 0.9915 (VARIANTTM) + 0.1198 %HbA1c (r=0.9936, P < 0.0001). Throughput was 28.0 tests per hour for A1c 2.2TM compared with 15.2 tests for VARIANTTM, which were determined including red blood cell lysis time before sample loading for VARIANTTM. A1c 2.2TM did not need sample pretreatment. CONCLUSIONS: With the above results, A1c 2.2TM shows acceptable performance and is suitable for routine use in the clinical laboratory.
Chromatography, High Pressure Liquid ; Chromatography, Liquid ; Erythrocytes

Amitriptylin hydrochloride is used as the internal standard in place of desipramine hydrochloride to determine the amount of imipramine hydrochloride by HPLC method. Results: Amitriptylin have the same structure as imipramin and the resolution degree between amitriptylin and imipramin is 1.8 while resolution degree between iminodibenzyl and imipramin is very high (R=10.7) because molecule structure of iminodibenzyl do not have branch-circuit. The suitability of chromatographic system through coefficient got high stable results with RSD<1.0%. Amitryptilin hydrochloride can be used as the internal standard in place of desipramine hydrochloride if necessary to test splitting degree in determination of imipramine hydrochloride
Imipramine ; Chromatography ; High Pressure Liquid

System suitability tests are an integral part of liquid chromatographic technique. They are used to verify the resolution (R) and reproducibility of the analysis to be done. HPLC method for assaying the related substances test of Cefaclor in raw material as well as in pharmaceutical dosage forms introduced to some pharmacopoeia such as EP, USP need to use Delta- 3 cefaclor as the internal standard to verify the suitability of chromatographic system. In case of lacking it to use, Cephalexin can be used as the internal standard in place of Delta-3 cefaclor. cell
Chromatography, High Pressure Liquid ; Cefaclor

This work was launched to study on the chemical constituents from Euphorbia thymifolia. Thirteen compounds were isolated from the 95% ethanol extract of the aerial parts of E. thymifolia by column chromatographies on silica gel, Sephadex LH-20, MCI, and ODS, and preparative HPLC, including two thymol derivatives(1-2), four alkaloids(3-6), five isocoumarins(7-11), together with two ellagic acids(12-13). All the compounds are listed as follows:(Z)-8,9-dehydro-9,10-diisobutyryloxythymol(1), 8-hydro-xy-9,10-diisobutyryloxythymol(2), N-(N-benzoyl-L-phenylalanyl)-L-phenylalanol(3), aurantiamide acetate(4), 1-carboethoxy-β-carboline(5), isoechinulin A(6), ethyl brevifolincarboxylate(7), euphorhirtin B(8), 4,5-didehydro chebulic acid triethyl ester(9), euphorhirtin G(10), pomegranatate(11), 3,3',4'-tri-O-methylellagic acid(12), 3,3'-di-O-methylellagic acid(13). Compound 1 is a new compound. Except for compound 4, the others were isolated from this plant for the first time. All the compounds were screened for anti-neuroinflammatory activity in vitro, and compounds 1-3 and 7 showed significant activity with IC_(50) values of 0.19,12.93,7.29,25.4 μmol·L~(-1).
Chromatography, High Pressure Liquid ; Euphorbia

This project is to study chemical compositions from the stems of Herpetospermum pedunculosum. Twenty-two compounds were isolated from the 70% acetone extract of the stems of H. pedunculosum by column chromatography on Sephadex LH-20, semi-preparative HPLC and preparative TLC. Their structures were elucidated by their physicochemical properties and spectroscopic data as N-benzyltyramine(1), α-spinasterol(2),(2S)-1-O-heptatriacontanoyl glycerol(3), 5,7-dihydroxychromanone(4), methyl 2β,3β-dihydroxy-D:C-friedoolean-8-en-29-oate(5), p-hydroxy benzyl alcohol(6), p-hydroxybenzoate(7), p-hydroxy cinnamic acid(8), 1H-indol-3-carboxylic acid(9), rhodiocyanoside B(10), rhodiolgin(11), rhodiosin(12), 9,12,13-trihydroxy-10(E)-octadecenoic acid(13), cylo-(Tyr-Leu)(14), matteflavoside A(15), loliolide(16), 1H-indol-3-carboxaldehyde(17),(+)-dehydrovomifoliol(18), 3-hydroxy-5α,6α-epoxy-β-ionone(19), 3-hydroxy-1-(4-hydroxy-3-methoxyphenyl)-2-[4-(3-hydroxy-1-propen-1-yl)-2-methoxyphenoxy]-1-propanone(20), 7-en-nonadecanoic acid monoglyceride(21), vanillic acid(22). Compound 1 is a new natural product, while compounds 3-15 were isolated from this plant for the first time.
Chromatography, High Pressure Liquid ; Cucurbitaceae

Objectives: The aim of this study is to establish a Reversed Phase – High Performance Liquid Chromatographic (RP-HPLC) method for the quantification of Rhein from Cassia fistula L. leaves. Methods: A Shimadzu system equipped with a C18 Column (150 x 4.6 mm, 5 μm) with an isocratic elution of Acetonitrile (solvent A) and 0.1% trifluoroacetic acid aqueous solution (solvent B) (Merck, 1.08178.0050) with a 55:45 ratio, respectively and a flow rate of 1.0 mL/min and sample injection of 10 μL detection was done at 230 nm. Standard solution of Rhein (Chengdu Biopurify) was prepared for method development. This study was validated using the guidelines set under “ICH Topic Q2 R2 or the Validation of Analytical Procedures”. Procedures for linearity, precision, accuracy, limit of detection, and limit of quantitation were performed. Results: The retention time of Rhein standard was determined at 5.10 minutes. LOD and LOQ were determined to be 1.278 mcg/mL and 3.872 mcg/mL, respectively with good linearity (R2 ≥0.996) with a linear range of 2.5-20 ug/mL of the Rhein standard. The accuracy of the method was determined based on % recovery method and ranged from 94.75%-100.32% (intraday, n=3) with %RSD of 0.71. The intraday precision %RSD was 2.92 (n=6) while interday precision %RSD was 3.75 (n=3). The method was able to check the Rhein quantity among 10 samples of Cassia fistula L. leaves from different locations in the Philippines. Conclusion The method was found to be sensitive and accurate for the quantification of Rhein. The method was found to be useful for the quantification of the amount of Rhein and can be used as a Quality Control tool for the assessment of Cassia fistula.
Cassia ; Chromatography, High Pressure Liquid

OBJECTIVES

The aim of this study is to establish a Reversed Phase – High Performance Liquid Chromatographic (RP-HPLC) method for the quantification of Rhein from Cassia fistula L. leaves.

A Shimadzu system equipped with a C18 Column (150 x 4.6 mm, 5 μm) with an isocratic elution of Acetonitrile (solvent A) and 0.1% trifluoroacetic acid aqueous solution (solvent B) (Merck, 1.08178.0050) with a 55:45 ratio, respectively and a flow rate of 1.0 mL/min and sample injection of 10 μL detection was done at 230 nm. Standard solution of Rhein (Chengdu Biopurify) was prepared for method development. This study was validated using the guidelines set under “ICH Topic Q2 R2 or the Validation of Analytical Procedures”. Procedures for linearity, precision, accuracy, limit of detection, and limit of quantitation were performed.

The retention time of Rhein standard was determined at 5.10 minutes. LOD and LOQ were determined to be 1.278 mcg/mL and 3.872 mcg/mL, respectively with good linearity (R2 ≥0.996) with a linear range of 2.5-20 ug/mL of the Rhein standard. The accuracy of the method was determined based on % recovery method and ranged from 94.75%-100.32% (intraday, n=3) with %RSD of 0.71. The intraday precision %RSD was 2.92 (n=6) while interday precision %RSD was 3.75 (n=3). The method was able to check the Rhein quantity among 10 samples of Cassia fistula L. leaves from different locations in the Philippines.

The method was found to be sensitive and accurate for the quantification of Rhein. The method was found to be useful for the quantification of the amount of Rhein and can be used as a Quality Control tool for the assessment of Cassia fistula.

BACKGROUND: Hemoglobin A1c (HbA1c) is widely used for the monitoring of glycemic control. A wide variety of different analytical methods is currently used by clinical laboratories. We performed this study to evaluate the newest ion-exchange high-performance liquid chromatography system, the HLC-723 G7 (Tosoh Corporation, Tokyo, Japan) automated glycohemoglobin analyzer. METHODS: HLC-723 G7 was evaluated for linearity, precision, comparison of method, and speed. HLC-723 G7 was compared with three analyzers including HLC-723 GHb V A1c 2.2, Variant II, and Cobas Integra 800. RESULTS: HLC-723 G7 showed within-run and total imprecision (CVs) of less than 2.5% and excellent linearity to at least 13.0%. HbA1c values obtained from HLC-723 G7 were strongly correlated with those from HLC-723 GHb V A1c 2.2. Comparison with two other methods showed a good correlation but revealed calibration differences throughout the analytical range. HLC-723 G7 required no sample preparation and showed a fast analytical time of 1.6 min. CONCLUSIONS: HLC-723 G7 provides high throughput and excellent precision. However, HbA1c values can differ considerably with different methods or instruments. Therefore, we should be aware of the potential problem in switching the HbA1c testing method
Calibration ; Chromatography, High Pressure Liquid ; Chromatography, Liquid ; Diabetes Mellitus

BACKGROUND: We evaluated overall performance and analysis time of newly developed HLC-723 G8 (Tosoh corp., Tokyo, Japan) HbA1c autoanalyzerwhich utilizes cation-exchange HPLC method. METHODS: Linearity, precision, correlation with Variant II Turbo (Bio-Rad Laboratories, Hercules, CA, USA), analysis time, labile HbA1c (L-A1c) separation ability and stability of refrigerated sample at 4degrees C were evaluated. RESULTS: HLC-723 G8 showed good linearity between HbA1c 4.9-12.0% range (R2=0.9995). Within-run and total imprecision (CVs) were less than 1.0%. Correlation with Variant II Turbo and L-A1c separation ability were excellent. Analysis time per sample took 1.0 min. Stability of refrigerated sample at 4degrees C for at least 21 days was good. CONCLUSIONS: HLC-723 G8 showed good analytical performance and its rapid analysis time enables us to support outpatient diagnosis of diabetic patients efficiently.
Chromatography, High Pressure Liquid ; Humans ; Outpatients ; Tokyo

OBJECTIVETo investigate the effect of different chromatographic conditions on QAMS relative correlation factors (RCF) and relative retention values (RT(R)).

METHODC18 columns were used with methyl alcohol-0.4% phosphoric acid water (85: 15) as the mobile phase. The detection wavelength was 254 nm, the column temperature was 30 degrees C, and the flow rate was 1.0 mL x min(-1). The five anthraquinones in Rhei Radix et Rhizoma were selected to be the objects of study. The RCF and RT(R) among aloe-emodin, rhein, chrysophanol, physcion and emodin were determined under different chromatographic conditions.

RESULTTheir RCFs showed no significant difference.

CONCLUSIONThe RCFs among anthraquinones established by QAMS can be used as a constant in content determination of traditional Chinese medicines/patent traditional Chinese medicines.