• Bulletin of the Korean Chemical Society
• /
• v.34 no.12
• /
• pp.3629-3634
• /
• 2013

In this study, an improved method for the quantitative analysis of ginkgolic acids (GAs) in Ginkgo biloba leaf extract was developed. The samples were extracted with a mixture of chloroform and 50 % ethanol, after which the chloroform extract was dried and reconstituted in methanol. GAs with 13:0, 15:1, and 17:1 in the extract were successfully separated within 40 min and determined with high throughput performance using an online column-switching HPLC method using an SP column C8 SG80 ($4.6{\times}150mm$, $5{\mu}m$) and a Cadenza 5CD C18 column ($4.6{\times}150mm$, $3{\mu}m$). The developed HPLC method was validated for Ginkgo biloba leaf extract. The validation parameters were specificity, linearity, precision, accuracy, and limits of detection and quantitation (LODs and LOQs, respectively). It was found that all of the calibration curves showed good linearity ($r^2$ > 0.9993) within the tested ranges. The LODs and LOQs were all lower than $0.04{\mu}g/mL$. The established method was found to be simple, rapid, and high throughput for the quantitative analysis of GAs in ten commercial Ginkgo biloba leaf extract and dietary supplements. The samples were also analyzed in LC-electrospray ionization (ESI) tandem mass spectrometry (MS/MS) - multiple-ion reaction monitoring (MRM) mode to confirm the identification results that were obtained by the column switching HPLC-DAD method. The developed method is considered to be suitable for the routine quality control and safety assurance of Ginkgo biloba leaf extract.

• Journal of Korean Society on Water Environment
• /
• v.28 no.6
• /
• pp.843-850
• /
• 2012

Due to the fast response to algae bloom issue in drinking water treatment plant, very fast determination methodology for algal toxin is required. In this study, column switching technique based online preconcentration method was combined with high resolution full scan mass spectrometer to save sample preparation time and to obtain fast and accurate result. After parameter optimization of online preconcentration, 1mL filtered sample was directly injected to trap column with switching valve system. Next, target toxins are eluted by 98% acetonitrile and analysed with 150 - 1,100 amu scan range at 50,000 resolving power. Method detection limit (MDL) for microcystin-LR, the most toxic isomer, was 0.1 ng/mL and others such as microcystin-YR, microcystin-RR and nodularin were 0.08, 0.03 and 0.04 ng/mL, respectively. This is the best improved sensitivities with 1mL volume in the literature. Furthermore, due to the use of ultra pressure HPLC (UPLC), the whole method run was completed in 4 min. Real sample applications for 173 sample including 55 surface water and 118 treatment plant samples for raw and treated water could be done within 16 hours. In our calculation, this methodology is roughly 80% faster than the previous manual solid-phase extraction with LC-MS/MS method.

• Journal of Pharmaceutical Investigation
• /
• v.41 no.2
• /
• pp.117-123
• /
• 2011

Loxoprofen sodium, a 2-phenylpropionate non-steroidal anti-inflammatory drug (NSAID), has marked analgesic and antipyretic activities and relatively weak gastrointestinal ulcerogenicity. The purpose of the present study was to evaluate the bioequivalence of two loxoprofen sodium tablets, Hana loxoprofen sodium tablet (Hana Pharm. Co., Ltd.) and Dongwha Loxonin$^{(R)}$ tablet (Dongwha Pharm. Co., Ltd.), according to the guidelines of the Korea Food and Drug Administration (KFDA). The in vitro release of loxoprofen from the two loxoprofen sodium formulations was tested using KP IX Apparatus II method with various dissolution media. Twenty four healthy Korean male volunteers, $22.83{\pm}1.862$ years in age and $69.92{\pm}9.14$ kg in body weight, were divided into two groups and a randomized $2{\times}2$ crossover study was employed. After a single tablet containing 60 mg as loxoprofen sodium was orally administered, blood samples were taken at predetermined time intervals and the concentrations of loxoprofen in serum were determined using a online column-switching HPLC method with UV/Vis detection. The dissolution profiles of two formulations were similar in all tested dissolution media. The pharmacokinetic parameters such as $AUC^t$, $C_{max}$ and $T_{max}$ were calculated, and computer programs (Equiv Test and K-BE Test 2002) were utilized for the statistical analysis of the parameters using logarithmically transformed $AUC_t$, $C_{max}$ and un-transformed $T_{max}$. The results showed that the differences between two formulations based on the reference drug, Dongwha Loxonin$^{(R)}$ tablet, were 2.03, 2.99 and -9.49% for $AUC_t$, $C_{max}$, and $T_{max}$, respectively. There were no sequence effects between two formulations in these parameters. The 90% confidence intervals using logarithmically transformed data were within the acceptance range of log0.8 to log1.25 (e.g., log0.9831~log1.0535 and log0.9455~log1.1386 for $AUC_t$ and $C_{max}$, respectively). Thus, the criteria of the KFDA bioequivalence guideline were satisfied, indicating Hana loxoprofen sodium tablet was bioequivalent to Dongwha Loxonin$^{(R)}$ tablet.

• Journal of Pharmaceutical Investigation
• /
• v.41 no.5
• /
• pp.317-322
• /
• 2011

Sertraline HCl, (1S-cis)-4-(3, 4-dichloro-phenyl)-1, 2, 3, 4-tetrahydro-N-methyl-l-naphthalenamine hydrochloride, is a potent and selective serotonin reuptake inhibitor which is used in the treatment of depression and obsessivecompulsive disorders. The purpose of the present study was to evaluate the bioequivalence of two sertraline HCl tablets, Traline tablet (Myungin Pharm. Co. Ltd.) and Zoloft$^{(R)}$ tablet (Pfizer Inc.), according to the guidelines of the Korea Food and Drug Administration (KFDA). The in vitro release of sertraline from the two sertraline HCl formulations was tested using KP VIII Apparatus II method with various dissolution media. Twenty four healthy Korean male volunteers, $23.50{\pm}1.74$ years in age and $64.09{\pm}7.10\;kg$ in body weight, were divided into two groups and a randomized $2{\times}2$ crossover study was employed. After a single tablet containing 50 mg as sertraline HCl was orally administered, blood samples were taken at predetermined time intervals and the concentrations of sertraline in serum were determined using an online columnswitching HPLC method with UV/Vis detection. The dissolution profiles of two formulations were similar in all tested dissolution media. The pharmacokinetic parameters such as $AUC_t$, $C_{max}$ and $T_{max}$ were calculated, and computer programs (Equiv Test and K-BE Test) were utilized for the statistical analysis of the parameters using logarithmically transformed $AUC_t$, $C_{max}$ and un-transformed $T_{max}$. The results showed that the differences between two formulations based on the reference drug, Zoloft$^{(R)}$ tablet, were 0.04, 3.26 and -1.29% for $AUC_t$, $C_{max}$, and $T_{max}$, respectively. There were no sequence effects between two formulations in these parameters. The 90% confidence intervals using logarithmically transformed data were within the acceptance range of log0.8 to log1.25. Thus, the criteria of the KFDA bioequivalence guideline were satisfied, indicating Traline tablet was bioequivalent to Zoloft$^{(R)}$ tablet.