Nanoformulations: Clinoptilolite-Based Capsule with Lecithin Shell

Microporous materials can provide interesting tools for different goals from bioimaging to the delivery ofbioactive molecules. In this study, the procedure based on cryo-approaches was designed to formulate thenanoparticles of natural clinoptilolite from the Zeolites mineral family. Applying scanning electron microscopy,clinoptilolite samples were imaged. After aging in the ethanol solution of phosphatidylcholine (lecithin),nanoparticles were encapsulated in the lecithin envelope. The adsorption of lecithin by clinoptilolitenanoparticles was studied by registering the diminution of optical density (OD 235) for ethanol/lecithin solutionat 235 nm with UV spectrometry. The kinetics of lecithin/clinoptilolite complex development was shown toexhibit intricate behavior, when the adsorption of lecithin was followed with its gradual release resulting in theincrease of lecithin content in ethanol solution back toward the original level. The size distribution for thelecithin/clinoptilolite complex was determined with a dynamic light scattering technique. To our knowledge,there are no reports of natural clinoptilolite-based platforms that were used as the for a nanosized capsule withphospholipids shell.

Content Determination of Total Flavonoids and Shikimic Acid in Pine Needles of Pinus massoniana Lamb. in Wudang Area / 中国中医药信息杂志

Objective To establish a method to determine the contents of total flavonoids and shikimic acid in pine needles of Pinus massoniana Lamb.in Wudang Area.Methods Rutin was used as reference standard,and the content of total flavonoids in pine needles of Pinus massoniana Lamb. was determined by UV spectrometry at wavelength of 500 nm. The content of shikimic acid was determined by HPLC-DAD. The Fortis Xi C8 column (5 μm, 250 mm × 4.6 mm) was adopted with acetonitrile - 0.4% phosphoric acid solution (8:92, V/V) as mobile phase at the flow rate of 0.9 mL/min. The detection wavelength was 213 nm; the column temperature was 30 ℃; the injection volume was 20 μL. Results The linear range was 8.26-49.54 μg for rutin (r=0.999 4) with an average recovery of 99.2%, RSD=1.94%. The linear range was 10.26-61.56 μg for shikimic acid (r=0.999 4) with an average recovery of 99.5%,RSD=1.93%.The contents of total flavonoids in pine needles of Pinus massoniana Lamb.was 28.33 mg/g, and shikimic acid was 15.25 mg/g, respectively. Conclusion The method is simple, rapid, accurate and reproducible. It can be used for the content determination of total flavonoids and shikimic acid in pine needles of Pinus massoniana Lamb. in Wudang Area.

Study on the Interaction between Cefprozil and Bovine Serum Albumin by Spectrometry / 中国药房

OBJECTIVE:To study the interaction of cefprozil (CE) with bovine serum albumine (BSA). METHODS:Under the temperatures of 289,299 and 309 K,the interaction of CE with BSA for 50 min had been studied by fluorescence quenching, UV spectrometry and synchronous fluorescence spectroscopy. Quenching constant(KSV)and speed constant(Kq)were calculated by Stern-Volmer equation. Static quenching constant(KLB)was obtained by Lineweaver-Burk equation,and UV spectrogram was used to determine the type of quenching. Double logarithmic equation was used to calculate the binding constants (Kb) and the number of binding site(n). Thermodynamic equation was used to obtain ΔH,ΔS,ΔG. Hill's coefficients(nH)was obtained by Hill equa-tion. RESULTS:At three different temperatures,with CE concentration increasing,fluorescence intensity of BSA decreased regular-ly. The value of KSV,Kq,KLB,Kb and n and nH decreased with the temperature increasing. ΔH,ΔS and ΔG were lower than 0. The numbers of binding sites were approximately equal to 1 and nH<1. CONCLUSIONS:CE statically quench the fluorescence of BSA,and the binding of them have been found to certain extent. The process of binding is spontaneous exothermic process. The main binding forces include Hydrogen bonds and Van der Waals forces,and primary binding site for CE is located at sub-domain ⅡA of BSA. There was some negative cooperative effect. CE would not affect the conformation of BSA. The binding site of CE and BSA is near by tyrosine residue.

Pharmacognostic identification of Tadehagi triquetrum / 中草药

Object To identify Tadehagi triquetrum (L ) Ohashi Methods Characteristic identification, microscopic identification, and UV spectrometry were used Results Obvious variation was found in the tissue structures between the old and young leaves as well as the old and young stems Conclusion The result can be taken as the reference for identifying the quality of crude drug