Application progress in the charged aerosol detector / 国际药学研究杂志

In recent years, charged aerosol detector(CAD)has become a valuable tool for detecting substances with no ultraviolet absorption or with only end absorption. Its advantages inclucle broad linearity response range, high sensitivity and reproducibility, the signal response consistency independent of chemical structures, as well as the simply operable feature. This article briefly describes the working principle of CAD and introduces the application progress of the detector in the natural product and pharmaceutical detection as well as in the sugar, lipid, amino acid and surfactant analysis, so as to provide a reference for the liquid chromatographic analysis of non-volatile and semi-volatile compounds.

In vitro UV absorption properties and radical scavenging capacity of Morella parvifolia (Benth. ) Parra-Os. extracts

The goal of this research was to identify major compounds of the aerial parts of M. parvifolia (Benth.) Parra-Os., that could enhance its possible application as additive in dermocosmetic products, as well as evaluate the antioxidant properties. The extracts agreed with the broad-spectrum UVB/UVA absorption detected and could act as broad-spectrum sunscreens, covering the UVA and UVB range. Methanolic extracts showed an important antiradical capacity (0.46 and 0.47 g/µmol DPPH), TPC (37.58 and 51.41mg GAE/g DS) and TAC (1.12 and 3.31 mg C3GE/g DS) in fruits and leaves, respectively. M. parvifolia could be considered as a prospective source of natural UV-radiation absorbers with antioxidant capacity. Although the results have clearly demonstrated the potential photoprotection capacity, more studies are needed to enhance its application as an additive in pharmaceutical and medicinal formulations.

Determination of Sun Protection Factor (SPF) number of some aqueous herbal extracts.

The aim of the present study was to determine the ultraviolet (UV) absorption properties of aqueous herbal extracts of some commonly found vegetable sources by determining the sun protection factor (SPF) number. The in vitro SPF number is determined according to the spectrophotometric method described by Mansur et al. Aqueous herbal extracts were prepared and after dilution with alcoholic solutions the absorbance were recorded between 290-320 nm using UV-vis spectrophotometry. It was observed that all of the tested herbals showed some UV protection capabilities with aqueous coconut extract showing the highest SPF number of 7.38 while watermelon showed the lowest SPF number of 0.97.

Spectrophotometric determination of chlorpheniramine maleate and phenylpropanolamine hydrochloride in dosage forms.

A rapid and simple method for simultaneous determination of Chlorpheniramine Maleate (CPM) and Phenylpropa-nolamine Hydrochloride (PPM) by first derivative UV spectrophotometry has been developed in combined pharmaceutical dosage forms. The proposed method was successfully applied for the determination of drugs in physical mixture and commercial formulations and results showed good linearity, precision and reproducibility.

Spectrophotometric determination of chlorpheniramine maleate and phenylpropanolamine hydrochloride in dosage forms.

A rapid and simple method for simultaneous determination of Chlorpheniramine Maleate (CPM) and Phenylpropa-nolamine Hydrochloride (PPM) by first derivative UV spectrophotometry has been developed in combined pharmaceutical dosage forms. The proposed method was successfully applied for the determination of drugs in physical mixture and commercial formulations and results showed good linearity, precision and reproducibility.

Research of binding reaction mechanism for adenosine in traditional Chinese medicine with serum albumin / 中国药学杂志

OBJECTIVE: To study the binding mechanism between adenosine (Ade), an active component of some traditional Chinese medicines, and human serum albumin (USA). METHODS: The binding constant K and binding sites n were obtained by using fluorescence and UV absorption spectroscopy. In addition, the reaction mechanism was discussed. The energy transfer parameters of the reaction system were determined as was the effect of Ade on HSA's conformation on the basis of Fōrster theory. The binding reaction model of HSA with Ade was constructed through molecular simulation and compared with the experiment results. RESULTS: Ade could bind HSA to form static complex. The binding constant (K) was 1.39 × 10 L3 · mol-1 and binding sites (n) was 0.94. The binding distance r between Ade and HSA was very short, which indicated the phenomenon of energy transfer. Ade changed the hydrophobic environment of the binding domain in HSA and caused certain changes for micro area conformation. Computer molecular docking technology showed that the interactions of Ade with HSA were mainly hydrophobic interaction and hydrogen bonding between purine ring of Ade and amino acid residues of HSA. CONCLUSION: The theoretical calculation and experiment results were in consistency, which provided certain reference for the study of pharmacological mechanism for the active ingredient of some traditional Chinese medicines, adenosine. Copyright 2012 by the Chinese Pharmaceutical Association.

Detección de suero de quesería en leches ultrapasteurizadas mexicanas mediante la cuarta derivada del espectro de absorción / Rennet whey solids detection in Mexican ultrapasteurized milk using fourth derivative absortion spectrum

Presence of rennet whey solids in ultrapasteurized milk (UHT) commercialized in Mexico City was determined using fourth derivative of absorption spectrum method, which allows to know the variation in whey protein/total protein ratio (WP/TP). The quantification of WP/TP ratio was used as an indicator of adulteration with rennet whey solids. The method was standardized to evaluate the accuracy, linearity and repeatability by rennet whey addition in concentrations between 0-15%, in raw milk. Thirty samples of skim ultrapasteurized milk were analyzed during September, October and November; found values were compared to the ones of raw milk added with rennet whey solids (0-15%, in levels of 2.5%). A marginal difference was found in the WP/TP ratio for the 0% concentration between the two types of milk, while the rest of the concentrations showed a high significance (P < 0.01). Values above 13.5% of WP/TP showed rennet whey solids addition; 36.7% of the UHT milk samples were between 5% and 12% positive to rennet whey solids addition. The results indicated that fourth derivative of the absorption spectrum of the WP/TP ratio was a sensitive indicator to rennet whey solids additions.

Se determinó la presencia de suero de quesería en leches ultrapasteurizadas (UHT) comercializadas en la Ciudad de México mediante el método de la cuarta derivada del espectro de absorción, el cual permite conocer la variación de la relación proteínas de suero/proteína total (PS/PT). La cuantificación de la relación PS/PT se utilizó como indicador de la adulteración con suero de quesería. El método fue estandarizado evaluando la exactitud, linealidad y repetibilidad mediante la adición de suero en concentraciones entre 0%-15% a leche cruda. Se analizaron 30 muestras de leche ultrapasteurizada descremada durante septiembre, octubre y noviembre; los valores encontrados se contrastaron con los de leche cruda adicionada con suero de quesería (0%-15%, en niveles de 2.5%. Se encontró una diferencia marginal en la relación PS/PT para la concentración 0% entre los dos tipos de leche, mientras que el resto de las concentraciones mostró una significancia alta (P < 0.01). Valores por encima de 13.5% de PS/PT expresaron adición de suero; 36.7% de las muestras de leche UHT fueron positivas a la adición de suero entre 5% y 12%. Los resultados indicaron que la cuarta derivada del espectro de absorción de la relación PS/PT fue un indicador sensible a adiciones de suero de quesería.

Prediction of UV Absorption Spectra of Vegetable Drugs and Its Potential Application / 中国药房

OBJECTIVE:To evaluate the possibility of detecting the chemicals illegally mixed in the vegetable drugs by ultraviolet spectrophotometry(UV).METHODS:The theoretical spectral absorption of Decoction of four drugs and Rhei and Aconiti praeparatae decoction were respectively defined as the weighted average of the spectral data of their respective prescription ingredients from ultraviolet scanning.Pearson's R values and the similarity between theoretical and actual spectra of the vegetable drugs were obtained with weighted correlation analysis(based on the correlation analysis,with larger weighted value around the peaks and valleys of UV absorption spectrum arranged).RESULTS:The similarity between theoretical and actual UV absorption spectra of the vegetable drugs was high with Pearson's R=0.98～0.999 5.CONCLUSION:The results show that UV absorption spectra of vegetable drugs can be exactly predicted by their prescription ingredients.It is possible to use the similarity between theoretical and actual spectra of vegetable drug to detect the chemicals illegally mixed because in such case it might lead to UV spectra change.