Indirect Electrochemical Analysis of Crocin in Phytochemical Sample

A new electroanalytical method has been developed for the quantitative determination of crocin in a sample of stigmas of saffron (Crocus sativus L.). Crocin is polarographically inactive. However, cysteine in 0.02 M NaCl, pH=5.2±0.01 produces a well defined wave/peak with E1/2/Ep= –0.47/–0.45 V vs. Ag/AgCl. On recording polarograms of a set of solution containing a fixed concentration of cysteine and varying concentrations of crocin under aforesaid experimental conditions a gradual decrease in peak height/diffusion current and a negative shift in peak potential was observed. Thus, indicating cysteine-crocin interaction. Amperometric titration indicated crocin to cysteine ratio of 1:2. The above amperometric titration procedure has been used to determine the concentration of crocin in a sample of saffron. Crystallization process was carried out for the extraction of crocin from dried powder of saffron stigmas. The crystallized crocin was identified by UV-Visible spectrophotometry(at 255 nm and 442 nm) and the quantitative analysis by the developed amperometric method. The concentration of crocin in saffron was found to be 2.13% and purity of isolated crocin 96.81%. The percent recovery varied from 98.56–100.31% and RSD (n=5) of 2.17%.The validation of the proposed procedure for the quantitative assay of crocin was examined via an evaluation of the repeatability, recovery, selectivity and relative standard deviation

Voltammetric DNA biosensor for the study of mechanism of action of anticancer drug-adriamycin

593-597The interaction of anticancer drug adriamycin with DNA has been studied using voltammetric DNA biosensor. The binding mechanism of adriamycin was elucidated by using differential pulse voltammetry (DPV) at DNA modified glassy carbon fiber electrodes (GCFE). The decrease in guanine oxidation peak current at +0.9 V was used as an indicator for interaction mechanism in acetate buffer (pH 4.5). The studied drug-DNA interaction mechanism at charged electrode surface is similar to the in-vivo DNA-drug complex formation, where DNA is in close contact with charged phospholipid membranes and proteins. Thus, the fabricated biosensor helps in understanding the in-vivo mechanism of action of this anticancer drug

Indirect Electrochemical Analysis of Crocin in Phytochemical Sample

A new electroanalytical method has been developed for the quantitative determination of crocin in a sample of stigmas of saffron (Crocus sativus L.). Crocin is polarographically inactive. However, cysteine in 0.02 M NaCl, pH=5.2±0.01 produces a well defined wave/peak with E1/2/Ep= –0.47/–0.45 V vs. Ag/AgCl. On recording polarograms of a set of solution containing a fixed concentration of cysteine and varying concentrations of crocin under aforesaid experimental conditions a gradual decrease in peak height/diffusion current and a negative shift in peak potential was observed. Thus, indicating cysteine-crocin interaction. Amperometric titration indicated crocin to cysteine ratio of 1:2. The above amperometric titration procedure has been used to determine the concentration of crocin in a sample of saffron. Crystallization process was carried out for the extraction of crocin from dried powder of saffron stigmas. The crystallized crocin was identified by UV-Visible spectrophotometry(at 255 nm and 442 nm) and the quantitative analysis by the developed amperometric method. The concentration of crocin in saffron was found to be 2.13% and purity of isolated crocin 96.81%. The percent recovery varied from 98.56–100.31% and RSD (n=5) of 2.17%.The validation of the proposed procedure for the quantitative assay of crocin was examined via an evaluation of the repeatability, recovery, selectivity and relative standard deviation

Connecting the Dots: Exploring the Relationship between Optical Coherence Tomography and 99mTc-TRODAT-1 SPECT Parameters in Parkinson's Disease

Background and Objective: While optical coherence tomography (OCT) is explored as a potential biomarker in Parkinson's disease (PD), technetium-99m-labeled tropane derivative (99mTc-TRODAT-1) single-photon emission computed tomography (SPECT) imaging has a proven role in diagnosing PD. Our objective was to compare the OCT parameters in PD patients and healthy controls (HCs) and correlate them with 99mTc-TRODAT-1 parameters in PD patients. Materials and Methods: This cross-sectional study included 30 PD patients and 30 age- and gender-matched HCs. Demographic data, PD details including Movement Disorders Society Unified Parkinson's Disease Rating Scale-III (MDS-UPDRS-III) and Hoehn–Yahr (HY) staging, and OCT parameters including macular and peripapillary retinal nerve fiber layer (RNFL) thickness in bilateral eyes were recorded. PD patients underwent 99mTc-TRODAT-1 SPECT imaging. The terms “ipsilateral” and “contralateral” were used with reference to more severely affected body side in PD patients and compared with corresponding sides in HCs. Results: PD patients showed significant ipsilateral superior parafoveal quadrant (mean ± standard deviation [SD] = 311.10 ± 15.90 vs. 297.57 ± 26.55, P = 0.02) and contralateral average perifoveal (mean ± SD = 278.75 ± 18.97 vs. 269.08 ± 16.91, P = 0.04) thinning compared to HCs. Peripapillary RNFL parameters were comparable between PD patients and HCs. MDS-UPDRS-III score and HY stage were inversely correlated to both ipsilateral (Spearman rho = -0.52, P = 0.003; Spearman rho = -0.47, P = 0.008) and contralateral (Spearman rho = -0.53, P = 0.002; Spearman rho = -0.58, P < 0.001) macular volumes, respectively. PD duration was inversely correlated with ipsilateral temporal parafoveal thickness (ρ = -0.41, P = 0.02). No correlation was observed between OCT and 99mTc-TRODAT-1 SPECT parameters in PD patients. Conclusion: Compared to HCs, a significant thinning was observed in the ipsilateral superior parafoveal quadrant and the contralateral average perifoveal region in PD patients. Macular volume and ipsilateral temporal parafoveal thickness were inversely correlated with disease severity and duration, respectively. OCT and 99mTc-TRODAT-1 SPECT parameters failed to correlate in PD patients