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At least 433 records · Page 24Linked to original sources
PubMed1975

Estimation of zinc concentration of parotid saliva by flameless atomic absorption spectrophotometry in normal subjects and in patients with idiopathic hypogeusia.

The concentraiton of zinc in parotid saliva was estimated by flameless atomic absorption spectrophotometry. As small a sample as 5 to 10 mul of whole paratid saliva can be analyzed quickly and reliably, without special sample handling and with littleinterference from other ions normally found in saliva. Parotid salivary zinc concentration in 34 subjects with normal taste acuity was 51 plus or minus 14 ppb(parts per billion)(mean plus or minus 1 S.D.); parotid salivary zinc concentration in 47 subjectswith idiopathic hypogeusia was 10 plus or minus 6 ppb (mean plus or minus 1 S.D.) which is significantly lower than that in normal subjects (p lessthan 0.001). This technique is a usual method by which to evaluate parotid salivary zinc, particulary inrelationship to problems of taste, appetite, and nutrition.

Ageusia↗
PubMed1997

[Determination of adenosine and thymidine in Fritillaria bulbs by dual wavelength ultraviolet spectrophotometry].

A convenient method for the quantitative analysis of adenosine and thymidine in Fritillaria bulbs was developed by means of dual wavelength ultraviolet spectrophotometry. This method has good linear relationship and the interrelated coefficient of standard curve for adenosine and thymidine were all found to be 0.9999. The methanol extracts of four species of Fritillaria have been analyzed with this method. The results show that the the bulbs of four species contain different quantities of adenosine and thymidine, which indicates that the nucleosides may be responsible for the anti-coagulation activity of Fritillaria.

Adenosine↗
PubMed1998

[Application of statistical simulation spectrophotometry to the determination of four medicaments in feibaosanxiao tablets].

The steps of statistical simulation spectrophotometry are to build a model based on a collection of limited but sufficient data from simulation samples to reveal the real absorbance-concentration relationship of the real sample and provide concentrated data of the individual components of the real sample measured by its absorbance data at several sensitive wavelengths. In this article, the method of stepwise regression has been used for building absorbance-concentration model of Feibaosanxiao tablets, a compound formulation of multimedicaments, and uniform design, for experimental design and recovery test. Recoveries of the four medicaments, acetaminophen, phenytoin sodium, theophylline and caffeine were 99.6%, 97.4%, 100.7% and 100.7% with RSD 0.3%, 1.9%, 1.3% and 1.3% respectively (n = 14).

Acetaminophen↗
PubMedDate not supplied

Applications of derivative UV spectrophotometry for the determinations of cetirizine dihydrochloride in pharmaceutical preparations.

A method for the determination of cetirizine dihydrochloride in pharmaceuticals by first-, second-, third- and fourth- order derivative spectrophotometry is described, using "peak-peak" (P-P), and "peak-zero" (P-0) measurements. The calibration curves are linear within the concentration range of 7.5-22.5 microg ml(-1) for cetirizine dihydrochloride. The procedure is simple, rapid and the results are reliable.

Cetirizine↗
PubMedDate not supplied

Simultaneous determination of promethazine, chlorpromazine, and perphenazine by multivariate calibration methods and derivative spectrophotometry.

Partial least-squares (PLS) regression, singular value decomposition-based PLS, and an artificial neural network (ANN) were tested as calibration procedures for the simultaneous determination of promethazine, chlorpromazine, and perphenazine by both conventional and derivative spectrophotometry. Comparison of the results revealed that the application of the ANN to the derivative spectra is superior to the application of the 2 PLS methods used. Different binary and ternary synthetic mixtures of the phenothiazine drugs in pure form and in tablets were analyzed by the proposed method, and acceptable results were obtained.

Calibration↗
PubMed1975

The application of spectrophotometry in the investigation of amniotic fluid by amnioscopy. part I. development of the technique.

A method for the incorporation of spectrophotometry to amnioscopy for the colourmetric estimation of amniotic fluid is presented. The spectrum of light reflected from the object under examination was measured using narrow-band interference filters, and a siliceous PIN light diode as the detector. A graphical representation of the spectrum was obtained using an automatic recorder. The preliminary measurements were performed using papers of various colours, clear amniotic fluid and green fluid as well as two patients in late pregnancy who required amnioscopic investigation. Measurements have shown that the apparatus can reliably distinguish different colours from each other and the authors consider that the apparatus may be used in connection with amnioscopy in order to estimate the colour of the amniotic fluid. The possible future use and development of such a technique is discussed.

Amniotic Fluid↗
PubMed1976

Detection of volatile solvents in gastric contents by gas phase infrared spectrophotometry.

A standard procedure for the identification of volatile solvents in the gas phase by infrared spectrophotometry has been modified and applied to the analysis of gastric contents. A 10 ml sample of the vapor from the gastric aspirate is removed with a hypodermic syringe, injected on a spectrophotometer from 2.5 to 15 nm. The sample is then identified by comparison with known reference spectra. Solvent concentrations cen be estimated by comparing the ratios of the major peaks.

Biopsy, Needle↗
PubMed1997

[Spectrophotometry analysis of berberine chloride in xianglian jiaowan].

After isolation of column chromatograph with organic solvent containing acid water, the content of berberine chloride in Xianglian Jiaowan (a Chinese drug) is determined by spectrophotometry. The analysis method is specific, sensitive and accurate, recovery is 99.8% and RSD is o.78%.

Berberine↗
PubMed2002

[Simultaneous determination of four components in the compound child phenobarbital tablet using ultraviolet spectrophotometry].

OBJECTIVE: To establish a method to determine four components in the child phenobarbital tablet. METHODS: Ultraviolet spectrophotometry was used to determine four components without separation. RESULTS: The contents of aspirin, phenacetin, caffeine and phenobarbital could be measured simultaneously. The average recoveries of four components in simulated samples and the compound child phenobarbital tablet samples were 99.0%, 98.9%, 99.8%, and 101%, respectively, and relative standard deviations of those were 2.0%, 2.0%, 2.9%, and 2.2%, respectively. CONCLUSION: The method is simple, fast, reliable, and can be used to monitor the quality of compound drugs.

Aspirin↗
PubMed1976

Determination of vitamin B12 in dry feeds by atomic absorption spectrophotometry.

Vitamin B12 was determined in dry feeds by atomic absorption spectrophotometry (AAS). Samples containing B12 were extracted with an assay solution, 5 g EDTA was added to the filtrate, the pH was adjusted to 7 with NH4OH, and 5 g charcoal was added. The charcoal was removed by filtering through ashless paper which was then placed in a beaker and ashed at 600 degrees C. After dissolving the cobalt oxide from the ash in 5N HNO3, cobalt content was determined by using AAS. To determine mg B12/lb feed, ppm cobalt in the feed is multiplied by 10.43. The sensitivity of the proposed procedure is 1 mg vitamin B12/lb. The procedure is rapid and precise, and results compare favorably with AOAC method 43.109.

Animal Feed↗
PubMed1976

Digestion of fish samples for mercury determination by flameless atomic absorption spectrophotometry.

Methods of digestion of fish samples for mercury determination by flameless atomic absorption spectrophotometry have been investigated. Digestion in Teflon bombs, Kjeldahl flasks, or borosilicate test tubes gives comparable precisions and mercury recoveries. Because of their cost and effect in limiting productivity, Teflon bombs were considered unnecessary for analysis of fish samples. Experiments with cooked and uncooked fish samples have confirmed that no appreciable loss of mercury occurs during baking 30 min at 170 degrees C.

Fish Products↗
PubMed2002

[Assay for paracetamol by derivative spectrophotometry in compound amantadine tablets].

Compound amantadine tablets is a new drug for virus-common cold. It was consisted of paracetamol, amantadine hydrochloride and caffeine etc. Because of the disturbing of the caffeine, the paracetamol can not be determined by UV directly. So the paracetamol in compound amantadine tablets was determined by derivative spectrophotometry. This method is simple and rapid, no distillation and no separation, with average recovery of 100.0%, and RSD of 0.36%.

Acetaminophen↗
PubMed1992

[Zero-crossing derivative spectrophotometry for the determination of three components in paracetamol compound tablets].

The zero-order derivative absorption spectra of aspirin, paracetamol and caffeine are closely overlapping. In this paper, a zero-crossing derivative spectrophotometry combined with simultaneous equations is proposed for the determination of the three components in a mixture without the need of prior separation. Satisfactory results were obtained. The method is reproducible, accurate and rapid. Calculation is not complicated. This method could be applied to biological fluid analysis.

Acetaminophen↗
PubMed2003

[Determination of trace Rh in organic residue by flame atomic absorption spectrophotometry].

The catalytic organic residue contained Rh was digested with HNO3 at 130 degrees C for 12 h. Trace noble metal Rh in catalytic organic residue was determined by flame atomic absorption spectrophotometry. Rh was atomized by air-acetylene flame at lamp Current of 7 mA. The methods of sample pretreatment for Rh in residue were compared in this paper. The recovery rates of this method were 95.3%-105.5% and the relative standard derivation was 0.9%. The method was applied to the analysis of some practical samples and the results obtained were satisfactory.

Acetylene↗
PubMed2003

[Study on the effect of extraction behaviour of molybdenum (V) thiocyanate complex in the dimethyl sulfoxide and water system by spectrophotometry].

In this paper the effect of petroleum sulfoxide-carbon tetrachloride used as extractant on the extraction behaviour of molybdenum (V) thiocyanate complex at different concentration of dimethyl sulfoxide and water system is studied by spectrophotometry. The mixture ratio of extraction is directly calculated using spectrophotometric data. Functional relation of mixture ratio and concentration of thiocyanate in mixed solution is discussed. By increasing the percent of volume of dimethyl sulfoxide in mixed solution, the effects of mixture ratio and percentage of extraction were studied. The experimental results were explained. It shows that the extraction system of MoO (SCN)3 has an application value.

Chelating Agents↗