ABSTRACT
Amyloid deposits are one of the hallmark pathological lesions of Alzheimer's disease (AD). They can be visualized by thioflavin-S, silver impregnation, Congo red staining, and immunohistochemical reactions. However, that amyloid deposits generate blue autofluorescence (auto-F) has been ignored. Here, we report that visible light-induced auto-F of senile plaques (SPs) was detected and validated with conventional methods. Brain slices from APP/PS1 (amyloid precursor protein/presenilin 1) transgenic mice were mounted on slides, rinsed, coverslipped and observed for details of the imaging and spectral characteristics of the auto-F of SPs. Then the slices were treated with the above classic methods for comparative validation. We found that the SP auto-F was greatest under blue-violet excitation with a specific emission spectrum, and was much easier, more sensitive, and reliable than the classic methods. Because it does not damage slices, observation of auto-F can be combined with all post-staining techniques in slices and for brain-wide imaging in AD.
ABSTRACT
OBJECTIVE:To develop a method for simultaneous determination of 6 alkaloids in Coptis teeta.METHODS:The determination was performed on XtimateTM C18 with mobile phase consisted of 30 mmol/L ammonium bicarbonate [containing 0.1％ triethylamine and 0.7％ ammonia-acetonitrile (gradient elution)] at the flow rate of 1.0 mL/min.The detection wavelength was set at 270 nm,the column temperature was 30 ℃,and the sample size was 10 μL.RESULTS:The linear ranges of jateorrhizine,columbamine,epiberberine,coptisine,palmatine hydrochloride and berberine hydrochloride were 0.85-16.96 mg/L (r=0.999 9),1.25-24.96 mg/L(r=0.999 8),2.05-40.96 mg/L(r=0.999 9),3.65-72.96 mg/L(r=0.999 9),2.88-57.60 mg/L(r=0.999 9) and 13.25-264.96 mg/L(r=0.999 9),respectively.RSDs of precision,stability and reproducibility tests were all lower than 3.0％.Recoveries were 97.14％-102.14％ (RSD=1.93％,n=6),97.00％-102.00％ (RSD=2.06％,n=6),98.18％-101.82 ％ (RSD=1.79％,n=6),96.15％-101.28％ (RSD=2.06％,n=6),96.88％-101.88％ (RSD=1.87％,n=6),99.31％-103.76％ (RSD=1.89％,n=6),respectively.CONCLUSIONS:The method is simple,accurate,stability and reproducible,and can be used for simultaneous determination of 6 alkaloids in Coptis teeta.
ABSTRACT
AIM : To set up a method of determinting the contents of four iridoid glycosides in different preparations of Lamiophlomis rotata ( Benth.) kudo.METHODS : The quantitative analysis was carded out on a column of Waters Symmetry by HPLC using a mobile phase of CH_3OH-H_2O under a flow rate of 1.0 mL/min.235 nm was selected as the detective wavelength.RESULTS: The linear ranges were 0.236-1.18 μg for sesamoside,0.440-2.20 μg for shanzhiside methyl ester,0.094-0.470 μg for 7,8-dehydropenste moside、0.750-3.75 μg for 8-O-ace-tylshanzhiside methyl ester.The recoveries of them were all between 96% and 104% ( RSD ＜ 5% ).CONCLUSION: The method is accurate,stable,reliable,and can be used as a quantitative standard for determining the contents of iridoid glycosides in different Duyiwei preparations.
ABSTRACT
AIM:To set up a method of determinting the contents of four iridoid glycosides in different preparations of Lamiophlomis rotata(Benth.)kudo.METHODS:The quantitative analysis was carried out on a column of Waters Symmetry by HPLC using a mobile phase of CH_3OH-H_2O under a flow rate of 1.0 mL/min.235 nm was selected as the detective wavelength.RESULTS:The linear ranges were 0.236-1.18 ?g for sesamoside,0.440-2.20 ?g for shanzhiside methyl ester、0.094-0.470 ?g for 7,8-dehydropenste moside、0.750-3.75 ?g for 8-O-acetylshanzhiside methyl ester.The recoveries of them were all between 96% and 104%(RSD