High performance liquid chromatography (HPLC) is currently the mainstream technology for detecting hemoglobin. Glycated hemoglobin (HbA1c) is a gold indicator for diagnosing diabetes, however, the accuracy of HbA1c test is affected by thalassemia factor hemoglobin F (HbF)/hemoglobin A2 (HbA2) and variant hemoglobin during HPLC analysis. In this study, a new anti-interference hemoglobin analysis system of HPLC is proposed. In this system, the high-pressure three-gradient elution method was improved, and the particle size and sieve plate aperture in the high-pressure chromatography column and the structure of the double-plunger reciprocating series high-pressure pump were optimized. The system could diagnose both HbA1c and thalassemia factor HbF/HbA2 and variant hemoglobin, and the performance of the system was anti-interference and stable. It is expected to achieve industrialization. In this study, the HbA1c and thalassemia factor HbF/HbA2 detection performance was compared between this system and the world’s first-line brand products such as Tosoh G8, Bio-Rad Ⅶ and D10 glycosylated hemoglobin analysis system. The results showed that the linear correlation between this system and the world-class system was good. The system is the first domestic hemoglobin analysis system by HPLC for screening of HbA1c and thalassemia factor HbF/HbA2 rapidly and accurately.
ObjectiveTo study the pharmacokinetics of lovastatin/niacin sustained-release tablets in healthy Chinese volunteers.
MethodsEligible subjects were enrolled to receive a single dose of 20/500, 20/750 and 20/1 000 mg lovastatin/niacin sustained-release tablets and multiple dose of 20/1 000 mg lovastatin/niacin sustainedrelease tablets, one time per day, sustained for 5 days, respectively. Blood samples were obtained before dosing and up to 10, 20, 30, and 45 minutes, and 1 hour, 1.5, 2, 2.5, 3, 3.5, 4, 5, 7, 9, 12, and 15 hours after dosing. Niacin, niacinamide, nicotinuric acid and lovastatin were detected by high performance liquid chromatography-tandem mass spectrometry method.
ResultsThe peak concertration and the area under the plasma concentration-time curve (0-t) of nicotinuric acid had linear dynamics characteristics with the dosage when the dose of niacin was between 500 and 1 000 mg. After multiple dosing, pharmacokinetics parameters of nicotinuric acid and lovastatin were close. No significant diTherence was found between male and female subjects.
ConclusionLovastatin/niacin sustained-release tablets possess linear kinetics. Accumulation is not significant after multiple dosing. Gender doesn't affect the pharmacokinetics parameters.
OBJECTIVE: To purify and study Schwann cells cytoplasmic neurotrophic protein. METHODS: The dissociated SC taken from 300 newborn rats sciatic nerves were cultured, collected, ultrasonicated and ultraspeed centrifuged. The supernates were ultrafiltrated and concentrated by using ultrafiltration units with PM10, PM30, PM50 ultrafiltration membranes. The ultrafiltrated-concentrated solution with the protein molecular weight 10-30 ku, 30-50 ku and gt; 50 ku were collected respectively. The dissociated spinal cord motoneurons of 14 days embryonic rats were cultured with serum-free conditional medium and the additional SC cytoplasmic proteins were added into the medium. The results showed that the 10-30 ku and gt; 50 ku SC cytoplasmic proteins were able to maintain the survival of motoneurons for 24 hours. Then the 26 ku and 58 ku proteins were further extracted and purified from SC cytoplasm by high pressure liquid chromatography, and their neurobiological activities were studied. RESULTS: The 26 ku and 58 ku Schwann cell’s cytoplasmic proteins were able to maintain the survival of motoneurons cultured in the serum-free medium for 48 hours. The highest biological activity concentration is 20 ng per well. CONCLUSION: Schwann cells cytoplasm contains motoneuron neurotrophic proteins with molecular weight 26 ku and 58 ku.
Objective To study the distribution and concentration of meropenem in rabbit bile. Methods The rabbits were cannulated with a silicone tube in the common bile duct and the blank bile was collected. The rabbits were then administered intravenously with meropenem. Multiple bile samples (1.5 ml) were collected at different phases after the administrations. According to requirement of the high performance liquid chromatography (HPLC), the specificity test was undertook. The blank bile was then mixed with meropenem and mobile phase, respectively, in order to obtain a series of bile samples at different concentrations ranging from 0.5 to 500 μg/ml. The samples were analyzed with HPLC and the chromatographic peak area of meropenem contents were quantitated through external reference method. The linear regression equation was used to analyzed the relationship between the drug concentrations and the chromatographic peak areas. The bile samples that were collected after drug administrations were pretreated and the chromatographic peak areas were assayed by the liquid chromatograph. The bile concentrations were then calculated according to the regression equation, and the concentration-time distribution of meropenem in the bile was obtained ultimately. Results The specificity test indicated the bile dopant peak and the meropenem chromatographic peak were well-separated under chromatographic condition of the mobile phase. The standard curve regression equation was S=2 209.10C-1 251.34, r=0.999 9, and minimum quantitation limit of meropenem was 0.5 μg/ml. After a single i.v. administration of 75 mg/kg of meropenem in each rabbit, drug concentrations reached (38.36±14.17) μg/ml immediately in bile， which significantly exceeded the minimum inhibitory concentrations (MIC90) for most gram negatives, which range from 0.031 to 2 μg/ml. The bile concentration of meropenem decreased quickly over time, and meropenem was eliminated completely in rabbit bile 3 hours after intravenous injection. Conclusion Meropenem could achieve adequate bile concentration for the treatment of biliary tract infection due to susceptible bacteria. However, because of its rapid biliary elimination, meropenem should be used in shorter interval time.
ObjectiveTo establish a method for content determination of ferulic acid in Piwang massage lotion.
MethodsHigh performance liquid chromatography was used. The analysis was carried on Diamonsil C18 (150 mm×4.6 mm, 5 μm, Dimma Science and Technology Co. Ltd.) column with mobile phase consisted of methanol-2% acetic acid (32︰68). The column temperature was 30℃. The detection wavelength was 320 nm.
ResultsThe responses of ferulic acid liner in range of 4.55-91.00 μg/mL (R2=0.999 9). The average recovery of ferulic acid was 98.78% (relative standard deviation is 2.668%).
ConclusionThe method is simple, rapid and good repeatability. It can be used for quality control of Piwang massage lotion
Objective To determine the best threshold value of hemoglobin A2 (HbA2) for diagnosis of β-thalassemia (β-thal) carriers by using high performance liquid chromatography (HPLC), and to improve the application value of HbA2 as a diagnostic index for β-thal carriers to reduce the rates of missed diagnosis and misdiagnosis. Methods Using reverse dot blot (RDB) as a gold standard method, HbA2 results of 1 007 β-thal carriers and 606 normal controls in the past two years determined by HPLC were divided into true positive, false positive, true negative, and false negative based on the different threshold values of HbA2 results. Then, the evaluation indexes such as sensitivity, specificity, positive and negative likelihood ratio, and Youden’s index were evaluated. Next, the receiver operator characteristic (ROC) curve was drawn to determine the best threshold value of HbA2 for diagnosis of β-thal carriers by HPLC. Results If ≥4.0% was taken as the threshold value of HbA2 for diagnosis of β-thal carriers by HPLC, the evaluation indexes values were shown as follows: sensitivity 99.21%, specificity 99.34%, positive likelihood ratio 150.30, negative likelihood ratio 0.008, and Youden’s index 0.99. The Youden’s index was better than the other threshold values, and the corresponding tangent point was the peak point of the ROC curve. Conclusion When ≥4.0% serves as the best threshold value of HbA2 for diagnosis of β-thal carriers using HPLC, integrated evaluation performance of the corresponding sensitivity and specificity is the most ideal, and the authenticity of the diagnostic test is the best.
ObjectiveTo investigate the diagnostic value of lateral chromatography for cryptococcal capsular polysaccharide antigen in cryptococcal infection.MethodsThe data of patients who detected cryptococcal capsular polysaccharide antigen in West China Hospital of Sichuan University in 2018 were collected. The sensitivity, specificity, positive predictive value and negative predictive value of cryptococcal capsular polysaccharide antigen detected by lateral chromatography were analyzed. The samples with positive lateral chromatography and definite clinical diagnosis were compared with the results of ink staining and fungal culture.ResultsA total of 721 cases were detected. The sensitivity, specificity, positive predictive value and negative predictive value of lateral chromatography detection were 100.00%, 99.39%, 93.93%, 100.00%, respectively. The positive rates of ink staining, fungal culture and cryptococcal capsular polysaccharide antigen for cryptococcal infection were 63.46%, 48.00% and 100.00%, respectively. Sixty-two patients were clinically diagnosed, including 45 cases of cryptococcal meningitis (72.58%), 16 cases of cryptococcal pneumonia (25.81%), and 1 case of bone cryptococcal infection (1.61%).ConclusionsLateral chromatography detection for cryptococcal capsular polysaccharide antigen shows well performing sensitivity and specificity in the diagnosis of cryptococcal infection. Considering its rapid and simple pre-operation, cryptococcal capsular polysaccharide antigen detection with lateral chromatography has good application value for early diagosis of cryptococcal infection.
We in this study measured the site density of E-selectin in order to explore the practical pliability using radionuclide labeling method and γ-imaging of single photon emission computer tomography (SPECT). This method required labeling of antibody with 125I using Indogen method and binding of the labeled antibody to E-selectin. Labeled E-selectin was separated and purified in a Sephadex G25 column. The different fractions of the eluants were imaged, analyzed and quantified with SPECT method. For measuring the saturation curve of E-selectin, 130 μL of E-selectin solution with different concentrations were added in a 48-well plate and incubated overnight at 4℃. After incubation, 130 μL of labeled antibody solution were added and kept incubated for 30 min. The resulted mixture was washed, and the radioactivity in each sample was detected by SPECT. The levels of radioactivity were translated to site densities, and were used to plot a standard curve. The labeled product was quantitatively analyzed with SPECT. The labeling rate of E-selectin was 78%. The saturation curve of different concentration samples showed that when the concentration was in the concentration range of 0-1 mg/mL, the standard curve was y=6 045.7x—51.166, R2=0.997 9. Based on this finding, it could be concluded that γ-imaging is an important tool for analysis of radiolabeled product and determination of site density.
ObjectiveTo determinate the concentration of isonicotinyl hydrazide (INH) in the hydrothorax and thereby increase the drug concentration of the hydrothorax to enhance the anti-tuberculosis efficacy through experiments.
MethodsBetween February and June 2009, we used high performance liquid chromatography (HPLC) to determinate the concentration of INH in the hydrothorax of tuberculosis (TB) patients. The separation of sample was performed on Agilent ZORBAX SB-C18 (5 μm, 4.6 mm×2.5 mm) column with a fixed sample injection volume of 20 μL. The mobile phase was methanol-water (20︰80) at a flow rate of 1 mL/min. The ultraviolet detective wavelength was set at 254 nm; The column temperature was room temperature.
ResultsIn the range of 0.25-10.00 μg/mL (r=0.998 9), moxi-floxacin showed a good linear relation in HPLC. The recoveries of moxi-floxacin at three concentrations (0.5, 5.0, and 10.0 μg/mL) were 97.95%, 100.64%, and 102.84%, respectively, with intra-day relative standard deviation (RSD) at 3.49%, 1.45%, and 2.03%, respectively and intra-day RSD at 3.85%, 5.68%, 4.15%, respectively.
ConclusionThe measuring method adopted in the experiment can accurately determinate the concentration of INH in the hydrothorax with high sensitivity and exceptional reproducibility.
ObjectiveTo study the effects of different penetration enhancers on the transdermal penetration of Miao medicine named Diploclisia affinis.
MethodsImproved Franz diffusion cell was adopted as the apparatus for in vitro mouse' skin permeation. The kinetic parameters of percutaneous absorption, such as penetration rate, enhancing rate (ER), and lag time (Tlag) were determined by high performance liquid chromatography. Azone, oleic acid (OA) and borneol were investigated for percutaneous absorption effects.
ResultsThe penetration rates of the medicine with 3% azone, OA and borneol added were respectively (214.1872±13.5690), (227.5544±9.8490), and (168.1187±21.5640) μg/(cm2·h), and the ER was 1.61, 1.71, and 1.26 compared with the penetration rate of that with nothing added. The Tlag was 2.1081, 1.8256, and 2.9655 hours.
ConclusionAll the penetration enhancers can increase significantly the absorption of Miao medicine named Diploclisia affinis, especially 3% OA is the best, but 3% borneol may make the Tlag longer.
