Simultaneous Determination of Six Residual Solvents in Phenylbutazone Raw Material by Head-space GC / 中国药房

OBJECTIVE： To establish a method for simultaneous determination of residual solvents in phenylbutazone raw material. METHODS： Head-space GC was adopted. The determination was performed on Agilent HP-5 capillary column by temperature programming. The temperature of injector was 200 ℃， and detector was flame ionization detector with temperature of 250 ℃； carrier gas was nitrogen （purity：99.99％） at the flow rate of 2.0 mL/min. The split ratio was 5 ∶ 1. Headspace equilibrium temperature was 60 ℃， and equilibration time was 30 min. The sample size was 1 mL. RESULTS： The linear range was 0.15-4.5   μg/mL for methanol （r＝0.999 9）， 0.25-7.5 μg/mL for ethanol （r＝0.999 7）， 0.25-7.5 μg/mL for isopropyl alcohol （r＝0.999 7）， 0.03-0.9 μg/mL for dichloromethane （r＝0.999 3）， 0.25-7.5 μg/mL for ethyl acetate （r＝0.999 3）， 0.044-1.32 μg/mL for N，N-dimethyl formamide （r＝0.999 3）， respectively. The limits of detection were 0.05， 0.08， 0.08， 0.01， 0.08， 0.015 μg/mL. The limits of quantitation were 0.15， 0.25， 0.25， 0.03， 0.25， 0.044 μg/mL. RSDs of precision test were lower than 2.0％. RSDs of stability and reproducibility tests were lower than 3.0％. The recoveries were 98.75％-100.12％ （RSD＝0.56％， n＝9）， 98.07％-101.20％ （RSD＝1.12％， n＝9）， 98.36％-100.80％ （RSD＝0.92％， n＝9）， 98.33％-101.67％ （RSD＝0.98％， n＝9）， 98.11％-100.40％ （RSD＝0.72％， n＝9） and 98.75％-101.05％ （RSD＝0.89％， n＝9）. CONCLUSIONS： The method is simple， accurate， precise， stable， reproducible and durable， and can be used for simultaneous determination of 6 residual solvents in phenylbutazone raw material.

Synthesis and physicochemical studies of vanillin chalcones / Síntesis y estudios fisicoquímicos de vainillin-chalconas

SUMMARY Some chalcone compounds are synthesized and their characterization was done by spectroscopic techniques such as IR, NMR and mass spectrometry. Some physicochemical properties such as acoustical properties, refractive index, conductance and partition coefficient have been studied for these synthesized compounds in N, N-dimethyl formamide and chloroform at 303.15 K. The studied properties are useful in QSAR studies and applications of these compounds in various other fields. It is observed that these parameters are affected by solvent and substitutions present in compounds.

RESUMEN Se sintetizaron algunos compuestos del tipo chalcona y su caracterizaron mediante técnicas espectroscópicas tales como IR, RMN y espectrometría de masa. Algunas propiedades fisicoquímicas tales como propiedades acústicas, índice de refracción, conductancia y coeficiente de reparto se estudiaron, para los compuestos sintetizados, en N,N-dimetil formamida y cloroformo a 303,15 K. Las propiedades estudiadas son útiles en estudios QSAR y en aplicaciones de estos compuestos en otros campos. Se observa que estos parámetros se ven afectados por el disolvente y las sustituciones presentes en los compuestos.

Synthesis, characterization and antibacterial screening of some Schiff bases derived from pyrazole and 4-amino antipyrine / Síntesis, caracterización y evaluación antibacteriana de algunas bases de Schiff derivadas de pirazol y 4-amino antipirina

Some Schiff bases of pyrazole and 4-amino antipyrine have been synthesized. The antibacterial screening of these synthesized compounds was done in dimethyl forma-mide against four Gram positive bacteria viz. Bacillus cereus, Staphylococcus aureus, Staphylococcus epidermidids and Micrococcus luteus, and three Gram negative bacteria viz. Proteus mirabilis, Escherichia coli and Klebsiella aerogenes. It is observed that in comparison to Schiff bases of 4-amino antipyrine, pyrazole Schiff bases are better for inhibition for these selected Gram positive and Gram negative bacterial strains.

Se sintetizaron algunas bases de Schiff a partir de pirazol y 4-amino antipirina. La evaluación de la actividad antibacteriana de estos compuestos en dimetil formamida se realizó frente a cuatro bacterias Gram positivas, Bacillus cereus, Staphylococcus aureus, Staphylococcus epidermidids y Micrococcus luteus, y frente a tres bacterias Gram negativas, Proteus mirabilis, Escherichia coli y Klebsiella aerogenes. Se observó mejor inhibición bacteriana frente a las diferentes cepas para las bases de Schiff basadas en pirazol comparadas con aquellas basadas en 4-amino antipirina.

Preparation of danshensu-polycaprolactone nanofiber scaffold by electrospinning / 中草药

Objective: To prepare Danshensu loaded polycaprolactone (DSS-PCL) nanofiber scaffold by using electrospin technology. Methods: Using dichloromethane-N, N-dimethyl formamide (CH2Cl2-DMF) 8:2 as solvent, nanofibers containing danshensu was prepared by electrospinning, fiber morphology was observed by SEM, danshensu in vitro release rule from drug loaded nanofiber scaffold was investigated, and the security of nanofiber was assessed by MTT and hemolysis test. Results: By using CH2Cl2-DMF as solvent, drug and materials could be well dissolved and successfully electrospun into nanofiber, the average fiber diameters were 210 and 190 nm, the in vitro release experiment showed that the drug release after a quick release into the slow release. MTT test indicated that PCL and DSS-PCL nanofiber showed no influence to the cell viability, and hemolysis test showed hemolysis ratio of nanofiber was under 5%. Conclusion: DSS-PCL nanofibers is easy to prepare by electrospinning.

Determination of residual formamide in allopurinol by gas chromatography / 重庆医科大学学报

Objective:To establish method for determination of residual formamide in Allopurinol by gas chromato-graphy.Methods:Detected by FID detector,Separated by SUPLCOWAX-10.Results:The formamide show a good linear relationship at range of 5～20?g/ml,the average recovery was 95.57%.(RSD=1.74%,n=6)for formamide.Conclusion:It is quite suitable to be used in analysis of the formamide in Allopurinol.

A simple protocol of DNA sequencing with 10% formamide for dissolving G/C compression

Formamide has been widely used in urea/polyacrylamide gel to solve the compression problems that are occasionally found during the DNA sequencing of G/C rich regions. In this study, however, 10% formamide was added in annealing solution in stead of adding to the gel. The compressions were unfolded efficiently with a more rapid annealing reaction on ice in the presence of 10% formamide.

Influence of formamide on the thermal stability of DNA.

The utility of formamide in the denaturation and renaturation of DNA has been examined. The melting temperature of duplex DNA is lowered by 0·6oC per per cent formamide. The depression of melting temperature is independent of the GC content. Formamide also increases the width of the thermal transition. Upto 30%, it does not affect the rate of DNA reassociation.