Humans ; Isoniazid ; blood ; Spectrophotometry, Ultraviolet

A new spectrophotometry was described for the simultaneous analysis of pseudoephedrine sulfate-Ioratadine combination. The derivative spectrophotometry dA/d values were read at zero-crossing point. Mean recoveries were found to be more than 98% for these compound in mixture. The procedure does not require any separation step and proven to be rapid, simple and accurate for determination of the mentioned sample or corresponding multi-component mixture
Spectrophotometry ; Ultraviolet Therapy ; Loratadine ; tablets

Humans ; Serum ; chemistry ; Spectrophotometry, Ultraviolet ; methods ; Sulpiride ; blood

Blood Chemical Analysis ; methods ; Humans ; Metronidazole ; blood ; Spectrophotometry, Ultraviolet

Azabicyclo Compounds ; blood ; Humans ; Piperazines ; blood ; Spectrophotometry, Ultraviolet

OBJECTIVETo explore the application of ultraviolet spectrophotometer in determining papaverine hydrochloride content in blood and skin and to determine the intradermal content after local external application of papaverine hydrochloride.

METHODSPhosphate buffer solution (pH = 10, ionic strength = 0.4) was added into the blood or ground skin tissue containing papaverine hydrochloride, and papaverine hydrochloride was extracted with chloroform-hexane mixture (ratio:2:3). After oscillation and centrifugation, partial organic phase was retrieved and dried in 60 degrees C water bath. The dried product was dissolved in 1 mol/L HCl and then underwent filtration through 0.2 micron membrane. The ultraviolet apectrophotometry was applied to determine the content of papaverine hydrochloride in the filtrate. 2% papaverine hydrochloride cream was applied on pig's skin and skin specimen was retrieved at given time to determine the papaverine hydrochloride content in skin tissue with ultraviolet spectrophotometry.

RESULTSThe absorbance spectrum of the extract was typical of that of papaverine hydrochloride, with no miscellaneous peak. The extractive rate of papaverine hydrochloride in blood of was more than 92% and that in skin tissue more than 87%. Eight hours after external application of 2% papaverine hydrochloride cream on pig skin, the content of papaverine hydrochloride in skin tissue was more than 90 micrograms/g, significantly higher than the effective concentration of papaverine hydrochloride.

CONCLUSIONSUltraviolet spectrophotometry is a simple, economical and reliable method for the determination of papaverine hydrochloride content in blood and skin tissue, with good reproducibility and sensibility. External application of papaverine hydrocholine cream can provide efficient permeation and drug concentration in the skin.

In this paper, a nucleic acid protein analyzer based on Lambert-Beer law and ultraviolet spectrophotometry is introduced, which is composed of ultraviolet monochromatic light generator, photoelectric signal detection module, vortex mixer, touch screen and embedded central controller. For ultra-micro measurement, a continuous-wavelength full-spectrum spectrophotometric detection circuit is designed in the hardware part. The transmitted light signal is collected by silicon photodiode, amplified and processed by subsequent circuit, and then transmitted to a single chip computer STM32F407VGT6 with CortexTM-M4 core after A/D conversion. The concentration and purity of nucleic acid protein are evaluated by assistant software detection algorithm. The instrument has the characteristics of compact size, flexible use, simple operation, high sensitivity and high detection efficiency. The experimental results show that the instrument has good sensitivity, repeatability and accuracy, and is suitable for the ultra-micro measurement of nucleic acid sample concentration, purity and protein concentration.
Algorithms ; Nucleic Acids/analysis* ; Proteins ; Software ; Spectrophotometry, Ultraviolet

An apigenin molecularly imprinted polymer was prepared by bulk polymerization using apigenin as template, acrylamide (AA) as a functional monomer, ethylene glycol dimethacrylate (EDMA) as a crosslinking agent, acetonitrile and N, N-dimethylformamide as porogenic solvents, and 2, 2'-azobisisobutyronitrile (AIBN) as an initiator. The interaction between template and functional monomer was proved by ultraviolet visible (UV) spectrophotometry and based on the results, appropriate reaction solvent was selected and the synthesizing process was estimated. The molecularly imprinted polymer structure was analyzed by Fourier Transform Infrared (FT-IR) spectrophotometry. The molecularly imprinted polymer was investigated in equilibrium binding experiment to evaluate its adsorption property, the results showed that the adsorption of apigenin on molecularly imprinted polymer is higher than that on blank polymer in the studied concentration range (0.1-2.5 mmol x L(-1)). Scatchard analysis showed that two classes of binding sites existed in the apigenin imprinted polymers, with their KD and Qmax estimated to be 2.52 x 10(-4), 0.54 x 10(-3) mmol x L(-1) and 2.65, 18.89 micromol x g(-1), respectively. Molecularly imprinted polymer showed higher affinity than blank polymer.
Apigenin ; chemical synthesis ; chemistry ; Molecular Imprinting ; Molecular Structure ; Polymers ; chemical synthesis ; chemistry ; Spectrophotometry, Infrared ; Spectrophotometry, Ultraviolet

To reveal the possible mechanism of silica deposition in higher plants, lignin was isolated from rice straw following a modified method to conduct a simulation experiment in vitro. UV and infrared absorption spectra showed that the substance had the unique characteristics of pure lignin. The presence of silicon in the precipitation was revealed by TEM (transmission electron microscopy) with EDXA (energy dispersive X-ray analysis) device. It was found that in the borax solution where lignin precipitation occurred silica-lignin co-precipitation was produced but not in the DMSO solution where lignin was broken into its composition compounds and did not precipitate. This means that it is macromolecular lignin itself but not its compounds that could induce silica deposition in higher plants.
Lignin ; analysis ; chemistry ; metabolism ; Microscopy, Electron, Transmission ; Oryza ; chemistry ; metabolism ; Silicon Dioxide ; analysis ; chemistry ; metabolism ; Spectrophotometry, Infrared ; Spectrophotometry, Ultraviolet

Aza Compounds ; analysis ; Heterocyclic Compounds ; analysis ; Sensitivity and Specificity ; Spectrophotometry, Ultraviolet ; methods ; Workplace