Tạp chí của Viện Kiểm nghiệm thuốc Trung ương
Nghiên cứu định lượng Ractopamin hydrochlorid tồn dư trong thịt gà bằng phương pháp LC-MS/MS
A method using ultra performance liquid chromatography tandem mass spectrometry was developed for determination of banned Ractopamin hydrochloride (RAC.HCl) substance in the chicken. The RAC.HCl was separated from chicken by SPE technique and was dissoluted in the mobile phase. The LC-MS/MS method with the chromatographic conditions as follows: A new column ACQUITY UPLC® BEH C18 (2.1 x 50 mm, 1.7 µm) packed with octylsilyl silica gel for chromatography was used as stationary phase, a mixture of 85 volumes of acetonitrile and 15 volumes of 0.1 % formic acid solution was used as the mobile phase with a flow rate of 0.2 ml per minute, using a tandem quadrupole mass detector. (ACQUITY UPLC H-Class’s Quaternary Solvent Manager; Xevo TQD, Waters).The exprimental results proved that the assay was linear over the concentration from 48 ng/ml to 9500 ng/ml. The LLOQ was 48 ng/ml. The method was validated about the specificity. The intra-day and inter-day accuracy were within 80.1 % - 115.4 %. (CV = 9.25-13.86 %). The validation results proved that this method was suitable for determination of Ractopamin in accuracy the chicken preparation.
Thẩm định phương pháp thử nghiệm độc tính tế bào in vitro bằng thuốc thử MTT trên tế bào Vero 76
The in vitro cytotoxicity assay method using the MTT reagent on Vero 76 cells was validated for system suitability, method suitability, specificity and repeatability. The validation results showed that the method using MTT reagent on Vero 76 cells was suitable for in vitro cytotoxicity testing of medical devices.
Xây dựng và thẩm định qui trình định lượng đồng thời desloratadin và chất bảo quản natri benzoat trong siro ho nghiên cứu bằng kỹ thuật sắc ký lỏng pha đảo
A Reversed-phase HPLC method for simultaneous determination of desloratadine and sodium benzoate in cough syrup was introduced. The method was carried out on a C18 column (4.6 mm × 250 mm, 5 mm), using an acetonitrile – phosphate buffer pH 3.0 mixture with composition varying following a gradient program as mobile phase. The mobile phase flow rate was maintained at 1.0 mL per minute. Injection volume was 50 µL. The UV detector was set at 274 nm. The developed method has been illustrated to statisfied the requirements of specificity, system suitability, linearity, accuracy, precision (repeatjability and intermediate precision) according to ICH-(Q2R1) guideline. The validation results indecated that the developed procedure was suitable for simultaneous determination of desloratadine anf sodium benzoate in studied cough syrup, and which would be a potential procedure to applied for other similar syrup matrix.
Xây dựng qui trình xác định giới hạn tạp chất liên quan tạp A của fenofibrat [(4-clorophenyl) (4-hydroxyphenyl)methanol] bằng phương pháp HPLC
A Reversed-phase HPLC method for determination of the related substance limit of fenofibrat impurity A was introduced: The chromatographic separation was done in a RP C18 (100 × 4.6 mm; 3.5 µm) column using mixture of 45 volumes of acetonitril, 55 volumes of water acidified to pH 2.5 with phosphoric acid as a mobile phase. The flow rate was maintained at 1.0 ml/min, detector was set up at 210 nm, and injection volume was 10 µl. The method was validated about the specificity, system suitability, linearity, linearity, accuracy and precision according to ICH (Q2R1) and which had LOD at 0.01 µg/ml. The results showed that the developed method was suitable for analyzing related substances of fenofibrate impurity A.
Xây dựng và thẩm định phương pháp định lượng Rabeprazol trong viên nén bao tan trong ruột
A simple reversed-phase HPLC method was developed for assay of rabeprazole in delayed-release tablets. The HPLC system consisted of a C18 column (150 × 4.6 mm, 5 µm), an mixture of acetonitrile - methanol - phosphate buffer pH 7.2 (25 : 25 : 50, v/v/v) maintaining at flow rate of 1.0 ml per minute as mobile phase, and a diode array detector was set at 284 nm for recording chromatograms of 10 µl of samples. The validation results indicated that in the working range from 32 - 48 µg/ml of rabeprazole, the studied method was satisfied the requirements of specificity, linearity, accuracy and precision according to AOAC international guideline. In short, the developed method was suitable for determining rabeprazole in delayed-release tablets.
Nghiên cứu xây dựng qui trình xác định chất chống côn trùng Deltamethrin trong màn sản xuất từ nhựa bằng sắc ký lỏng hiệu năng cao (HPLC)
A rapid, simple, sensitive and accurate high – performance liquid chromatographic method was developed and validated for determination of deltamethrin in Netprotect net. Deltamethrine was extracted from finely cut nets by xylene heating at 130-145 oC in 1 hour, the solvent was then evaporated to dryness and the residues reconstituded in mobile phase for HPLC analysis. The HPLC method employed a Thermo Hypersil silica column (150 × 4.6 mm; 5 µm) with a mixture of n-hexan - 1.4-dioxan (95 : 5, v/v) maintaining at flow rate of 1.0 ml/min as mobile phase. The injection volume was 20 µl and the UV-Vis detector was set at wavelength of 236 nm for recording chromatograms. The method was validated in terms of specificity, linearity, precision and accuracy according to current international requirements, and was proved as suitable and reliable for intended application. The method was applied to determine the content of deltamethrin in 9 samples of commercialized Netprotect nets, in which 5 samples were found containing levels of deltamethrine lower than the acceptance range.
Xây dựng qui trình định lượng acid Ganoderic A trong bào tử nấm linh chi bằng kỹ thuật sắc ký lỏng hiệu năng cao
A simple and accurate high performance liquid chromatography (HPLC) method was developed and validated for determination of ganoderic acid A in sporoderm-broken spores of Ganoderma lucidum (Lingzhi). The method was carried out on a C18 column (4.6 mm ´ 250 mm, 5 mm), using an acetonitrile – 0.1% trifluoroacetic acid solution mixture with composition varying following a gradient program as mobile phase. The mobile phase flow rate was maintained at 1.0 mL per minute. Injection volume was 10 µL. The UV detection was set at 256 nm. The method was validated in terms of linearity, specificity, precision and percentage recoveries. Validation results proved that the proposed method was suitable for determining the content of ganoderic acid A in sporoderm-broken spores of Genoderma lucidum.
Phân biệt dược liệu Ý dĩ và dược liệu Ý dĩ giả mạo
In this study, morphological description, powder microscopy and thin layer chromatography were used to distinguish between Coix Seed and its counterfeit. In thin layer chromatography method, the extract of Coix Seed in petroleum ether was developed by solvent system either petroleum ether : ethyl acetate : acetic acid (10 : 3 : 0.1) or petroleum ether : ether : glacial acetic acid (83 : 17 : 1), then visualized by spraying vanillin solution 5% in sulfuric acid and drying at 105 oC. Experimental results showed that morphological description and thin layer chromatography could be effective methods to discriminate genuine and counterfeit Coix Seeds.
Nghiên cứu xây dựng qui trình định lượng Cilnidipin trong huyết tương người bằng phương pháp LC-MS/MS
A simple, specific and sensitive LC-MS/MS method has been developed for determination of cilnidipine in human plasma. The analyte and the internal standard (losartan) were extracted from human plasma by the protein precipitation method with acetonitrile. The chromatographic conditions were achieved on the type of column (C18; 50 × 2.1 mm; 1.7 µm) with negative-ion electrospray ionization tandem mass spectrometric (ESI-MS/MS). Acquisition was performed in multiple reaction monitoring (MRM) mode, by monitoring the transitions including m/z = 491.14 -> 122.13 for cilnidipine and m/z = 421.13 -> 126.97 for IS, respectively. The mobile phase included acetonitrile and (10 mM ammonium acetate + 0.1 % formic acid) with suitable ratio at a flow rate of 0.2 ml/min. The method was validated over concentration range from 0.2 ng/ml to 20 ng/ml. The intra and inter-day precision and accuracy were within between 98.4 % and 113.9 %. This method can be used for BA-BE studies of cilnidipine preparations.
Định tính và định lượng chất chống năng octyl triazon trong mỹ phẩm dạng kem bằng phương pháp HPLC
A HPLC-based method was developed for identification and determination of Octyl triazone in cosmetic creams. Octyl triazone was extracted from cream matrices with ethanol and then 20 µl of sample solution was injected into chromatographic system with the following conditions: Phenomenex Gemini-C18 (250 x 4,6 mm; 5 µm) column maintaining at 40 0C, a mixture of methanol and ethanol (50 : 50) was used as the as a mobile phase, and DADdetector was set at wavelength of 310 nm for recording chromatograms. The developed method was validated over the range from 0.1 µg/ml to 30 µg/ml in term of specificity, linear range, precision and accuracy according to the USFDA guidelines. This method was suitable for determination of Octyl triazone in cosmetic creams.
Nghiên cứu xác định đồng thời ketamin và norketamin trong máu bằng sắc ký khí khổi phổ
Ketamine (KET) is widely abused for hallucination and is being seized more and more in Vietnam in recent years. An analytical method using gas chromatography – mass spectrometry with liquid – liquid extraction (LLE) was studied for determination of KET and its major metabolite, norketamine (NorKET), in whole blood. This was a very specific and sensitive method with the high accuracy, pecision. The low limites of detection (LOD) were 1,30 and 1,92 ng/mL for KET and NorKET, respectively. This method was applied to analyze six ketamine suspected whole blood sampes as well.
Định danh, sơ bộ xác định thành phần và tác dụng của loài Trà hoa vàng (Camellia Flava) trồng tại Tây Nguyên
Camellia flava in Tay Nguyen province was described in detail morphological and anatomical characteristics. Total phenolic and flavonoid contents in leaves were 104.36 ± 0.03 mg GAE and 14.49 ± 0.28 mg QE, respectively. The ethanol extracts of leaves performed the antioxidant and amylase inhibition activities. Moreover, the extracts of leaves and flowers from this species showed antimicrobial effects on Staphylococcus aureus, Moraxella catarrhalis and Haemophilus influenzae by agar diffusion method and minimum inhibitory concentration (MIC) had determined to compare with cefotaxime antibiotic, combined with the anti-inflammatory, illustrated by the similarity IC50 with aspirin, may develop respiratory protective products.
Nghiên cứu xây dựng qui trình xác định tiểu phân trong thuốc tiêm, thuốc tiêm truyền bằng kỹ thuật quét bán tự động trên hệ thống kính hiển vi BX51M-OLYMPUS
The system of the BX51M microscope is the first to be installed at the NIDQC for determining particle size in injections and infusions. This test should be carried out under precise conditions, according to the recommendation, to avoid the influence of free particles in the environment and in the glassware. The guidelines, on the other hand, do not go into detail about how to prepare particle-free water, how to clean the glassware, how do you rinse the membrane after filtration, or how long can you allow the filtered membrane to dry? These questions have been answered, and a detailed procedure for sample preparation and particle size determination has been established. Then, using the same procedure, we tested 12 samples collected from the market. The results demonstrated that all of the samples met the current pharmacopoeia’s requirements, and the approach used was appropriate. Furthermore, it can also be used to confirm a result in the case of an out-of-specification sample.
Phân biệt dược liệu Hậu phác và dược liệu Hậu phác nhầm lẫn, giả mạo
In this study, we use three methods including morphological description, powder microscopy and thin layer chromatography to distinguish between Cortex Magnoliae officinalis and counterfit Cortex Magnoliae officinalis. Experimental results show that with morphological description and powder microscopy, it is possible to preliminarily distinguish the difference. To confirm, it is necesary to conduct qualitative analysis by thin layer chromatography refer to Vietnamese Pharmacopoeia V and Chinese Pharmacopoeia 2015 in order to clearly identify Cortex Magnoliae officinalis and counterfit Cortex Magnoliae officinalis.
Định danh, sơ bộ xác định thành phần và tác dụng của lá trà hoa vàng (Camellia Hakodae) trồng tại Tây Nguyên
Camellia hakodae in Tay Nguyen province was described in detail morphological and anatomical characteristics. The total phenolic and flavonoid content in the leaves’ extract were found as 55.16 ± 0.02 mg GAE/g và 2.92 ± 0.06 mg QE/g, respectively. Moreover, the ethanol extract of leaves performed brilliantly the antioxidant activities (DPPH assay: IC50 = 63.88 μg/ml; ABTS assay: IC50 = 619.92 μg/ml; and total reducing power: EC50 = 219.55 μg/ml) and inhibited alpha amylase (IC50 = 0.64 mg/ml).
Xây dựng và thẩm định phương pháp LC-MS/MS định lượng đồng thời clopidogrel, aspirin và acid salicylic trong huyết tương người
A high throughput and specific method using ultra performance liquid chromatography tandem mass spectrometry for simultaneous determination of clopidogrel, aspirin and salicylic acid in human plasma was developed. The Waters Xevo TQD UPLC-MS/MS was operated under the multi reaction-monitoring mode using both of positive electrospray ionization and negative electrospray technique. Clopidogrel, aspirin, salicylic acid and internal standard were extracted from human plasma by liquid - liquid extraction technique using tert butyl methyl ether. The reconstituted samples were chromatographed on a C18 column (dimention 50 x 3 mm, particle 2.5 µm) with a gradient elution at a flow rate of 0.2 ml/min using 0.1 % formic acid in water – 0.1 % formic acid in acetonitrile. The standard curves were found to be linear in the range 10 to 10000 pg/ml, 10 to 2500 ng/ml and 70 to 3500 ng/ml for clopidogrel, aspirin, salicylic acid, respectively, with mean correlation coefficient of > 0.99 for all analysis. The intra-day and inter-day precision and accuracy were within 85 % - 115.0 %. Total run time was 4.5 min only. This method can be used for BA-BE studies of clopidogrel and aspirin combination preparations.
Xây dựng qui trình định lượng ketamin và một số thuốc dùng làm chất độn trong nước thải bằng GC-MS/ MS nhằm truy nguyên cơ sở sản xuất ketamin
Analysis of chemicals in wastewater has been proven as a tool for investigation of narcotic drug production site. In this study, a gas chromatographic tandem mass spectroscopic (GC-MS/MS) method was developed for the determination in wastewater of ketamin and 6 other drugs often used as diluent for ketamin: cafein, chlorpheniramine, diphenhydramine, dimethylsulfon, isopropylbenzyl and procain. The analysis method using liquid-liquid extraction for sample treatment. A column DB1-MS 30 m, id 0,25 mm x 0,25 mm was used with helium as carrier gas at 1,2 ml/min and multireaction monitoring at MS/MS detector. The method was validated with high repeatability (RSD % of 1.3 - 7.6 %), good recovery and linearity in the investigated range according to AOAC guidelines. Validation results showed that the developed method was suitable for determination ketamin and the 6 diluents in wastewater.
Xây dựng và thẩm định quy trình định lượng đồng thời rupatadine, methylparaben và propylparaben trong siro bằng phương pháp sắc ký lỏng pha đảo
A reversed-phase HPLC method for simultaneous determination of rupatadin, methylparaben and propylparaben in the studied syrup was introduced. The method was carried out on a C18 column (4.6 mm x 250 mm, 5 µm), using an acetonitrile - phosphate buffer pH 3.0 mixture (52/48, v/v) as mobile phase. The mobile phase flow rate was maintained at 1.0 mL per minute. Injection volumn was 20 µL. The UV dectector was set at 255 nm. The developed method has been illustrated to statisfied the requirements of specificity, system suitability, linearity, accuracy, precision (repeatability and intermediate precision) according to ICH-(Q2R1) guideline. The validation results indecated that the developed procedure was suitable for simultaneous determination of rupatadin, methylparaben and propylparaben in the studied syrup and may be applied in other similar products.
Xây dựng bộ dữ liệu hình ảnh soi bột và sắc ký lớp mỏng của 5 dược liệu Ngưu tất, Phòng phong, Xuyên khung, Hoàng cầm và Hoàng kỳ
In this study, we built a dataset of powder microscopic and thin layer chromatography images of 5 standard medicinal herbs including Radix Achyranthis bidentatae, Radix Saposhnivoviae divaricatae, Radix Ligustici wallichii, Radix Scutellariae, and Radix Astragali membranacei based on the methods described in Vietnamese Pharmacopoeia V. This image dataset can be used for comparison and reference in the process of testing medicinal herbs and preparations containing the medicinal herbs mentioned above.
Định tính và định lượng đồng thời benzyl alcohol, acid salicylic và natri benzoat trong dầu gội đầu bằng phương pháp HPLC
A HPLC-based method was developed for identification and determination of benzyl alcohol, salicylic acid, sodium benzoate in shampoo. These three analytes were extracted from shampoo matrices with methanol - water (1:1) and analyzed using an YMC – Triart C18 (250 x 4,6 mm; 5 µm) column as stationary phase, a mixture of phosphate buffer solution pH 2,7 and methanol (65:35, v/v) being maintained at flow rate of 1.2 mililiters per minute as mobile phase. The UV detection was set at wavelength of 208 nm for benzyl alcohol and at wavelength of 230 nm for salicylic acid and sodium benzoate. The developed method was validated in terms of specificity, linear range, precision and accuracy according to the requirements of AOAC International and FDA. This method was suitable for simultaneously determination of benzyl alcohol, salicylic acid, and sodium benzoate in shampoo.
Xác định đồng thời 10 chất có tác dụng chống nắng trong mẫu mỹ phẩm dạng kem bằng phương pháp HPLC-DAD
A HPLC-based method was developed for simultaneous identification and determination of 10 UV filters in cosmetic creams. UV filters were extracted from cream matrices with a mixture of methanol and acetate buffer pH 3.85 (80:20, v/v) following by chromatographic separation on Agilent Poroshell 120-C18 (100 x 4.6 mm; 2.7µm) column with a mixture of methanol and acetate buffer pH 3.85 with gradient program as mobile phase, maintaining at flow rate of 0.8 ml per minute, run time 25 minutes, temperature: 40 0C. The method was validated about the specificity, linear range, precision, accuracy, LOD, LOQ, and validation results proved that this method was suitable for determination of 10 UV filters in cosmetic creams. The method was applied to control 14 cosmetic samples (sunscreen and creams). The result show that the concentration of UV filters in samples from 0.02 % to 8.03 %.
Xây dựng phương pháp định lượng đồng thời metformin và empagliflozin trong huyết tương người bằng phương pháp LC-MS/MS
A high throughput and specific method using ultra performance liquid chromatography tandem mass spectrometry for simultaneous determination of metformin and empagliflozin in human plasma was developed. Metformin-d6 (MET-d6) and empagliflozin-d4 (EMP-d4) were utilized as internal standards. Extraction of the analytes from the human plasma was performed through acetonitrile precipitation technique. Chromatographic analysis was developed on a C8 column (dimention 50 x 2.1 mm, particle 1.9 µm) with isocratic elution at a flow rate of 0.2 ml/min using a mobile phase of 7.5 mM ammonium bicarbonate : acetonitril (65 : 35, v/v). The Thermo vantage UPLC-MS/MS was operated under the multi reaction-monitoring mode using the positive ion mode, with transitions at (m/z) 130.1 →71.1 for (MET), 468.2 → 355.0 for (EMP), 136.1 →77.1 for (MET-d6), and 472.2 → 359.0 for (EMP-d4). The obtained linearity covered the concentration ranges of 15 - 3000 ng/mL and 1.5 – 300.0 ng/mL for MET and EMP, respectively. Total run time was 3.8 min only. This method can be used for BA-BE studies of metformin and empagliflozin combination preparations.
Nghiên cứu xác định gelsemin trong máu bằng sắc ký lỏng khối phổ
Gelsemium elegans Benth. is a plant belonging to the genus Gelsemium (family Gelsemiaceae). G. elegans is a wellknown toxic plant and its main components are alkaloids. Gelsemine is the principle alkaloid in G. Elegans. In this study, a specific, sensitive and accurate liquid chromatography tandem mass spectrometry (LC-MS/MS) has been established for the determination of gelsemine in whole blood. The low limit of detection (LOD) was 0,01 ng/ml for gelsemine. This method was applied to analyze six whole blood samples of six people who were suspected of ingesting Gelsemium elegan.
Xây dựng qui trình định tính, định lượng đồng thời một số flavonoid trong Diếp cá trồng ở Nam Bộ và Lâm Đồng bằng phương pháp HPLC
Six flavonoid from Houttuynia cordata, was extracted and analyzed by reverse phase HPLC. These flavonoid were extracted with mixture of methanol – water (70:30), using ultrasound in 10 min. at 60 oC. The method HPLC was chromatographed on C18 column, (250 mm × 4.6 mm; 5 µm), the mobile phase is acid acetic 0.2 % - acetonitril with gradient program. The proposed method was fully validated with acceptable specificity, precision and accuracy. The method was applied to determine Rutin, Quercitrin, Hyperoside, Isoquercitrin, Afzelin and Quercetin in Houttuynia cordata, collected at 9 provines of Southern and Lam Dong. All studied flavonoid was detected in investigated samples, and result showed that quercitrin was the highest component.
Xây dựng phương pháp xác định đồng thời 4 hợp chất 14,15β-dihydroxyklaineanon, scopoletin, eurycomalalacton và 9-methoxycanthin-6-on trong rễ cây Bá bệnh (Radix Eurycomae longifoliae) bằng phương pháp sắc ký lỏng hiệu năng cao
The compound 14,15β-dihydroxyklaineanone, scopoletin, eurycomalactone and 9-methoxycanthin-6-one were biological active compound of Radix Eurycomae longifoliae. In this study, an analytical method was successfully developed and validated for determination simultaneously of 14,15β-dihydroxyklaineanone, scopoletin, eurycomalactone and 9-methoxycanthin-6- one in the root of Eurycomae longifoliae Jack based on RP-HPLC with DAD detector using a colunm C18 (250 x 4.6 mm, 5 µm) and a mobile phase as mixture of phosphoric acid 0.1 % and acetonitril according to the gradient program; the flow rate was maintained at 1.0 ml/min, and the choosen wavelength of DAD detector was at 260 nm. This procedure could be applied suitable for quantitation of 14,15β-dihydroxyklaineanone with LOQ value of 0.54 µg/ml; scopoletin with LOQ value of 0.72 µg/ml; eurycomalactone with LOQ value of 1.52 µg/ml; 9-methoxycanthin-6-one with LOQ value of 0.47 µg/ml and fully met all the requirements (specificity, linearity, pricision, repeatability, and accuracy) according to ICH and AOAC guidelines.
Xây dựng phương pháp định tính và định lượng 3,5-dimethoxy-4-hydroxy-1-β-D-glucopyranosid trong phần gỗ cây Bàn tay ma đỏ (Heliciopsis lobata) bằng phương pháp sắc ký lỏng hiệu năng cao
The compound 3,5-dimethoxy-4-hydroxy-1-β-D-glucopyranoside was a biological active compound being representative for the hepatoprotective activity of Heliciopsis lobata plant. In this study, an analytical method was successfully developed and validated for qualitative and quantitative determination of 3,5-dimethoxy-4-hydroxy-1-β-D-glucopyranoside in the wood of Heliciopsis lobata based on RP-HPLC couple with DAD detector using a seperation colunm C18 (250 x 4.6 mm, 5 µm) and a mobile phase as mixture of phosphoric acid 0.1 % and acetonitril at different ratios; the flow rate was maintained at 1.0 ml/min., and the choosen wavelength of DAD detector was at 272 nm. The performance of the developed HPLC analysis was controlled by evaluating the resolution between tachioside coumpound and the main analyte. This procedure could be applied suitable for quantitation of 3,5-dimethoxy-4-hydroxy-1-β-D-glucopyranoside with LOQ value of 0.66 µg/ml and fully met all the requirements (specificity, linearity, pricision, repeatability, and accuracy) according to ICH and AOAC guidelines.
Xây dựng phương pháp định lượng đồng thời 2 tạp chất định danh trong nguyện liệu tạp chất B của tetrazosin dùng thiết lập tạp chuẩn bằng sắc ký lỏng hiệu năng cao
A high-performance liquid chromatography (HPLC) method was developed to assay 2 related substances in impurity B of terazosin (IBT) including terazosin (TEZ) and impurity A of terazosin (IAT). The chromatographic analysis was developed on a column (250 x 4.6 mm; 5.0 µm) packed with octylsilyl silica gel for chromatography used as a stationary phase with the column temperature at about 30 oC. A mixture of 16 volumes of acetonitrile and 84 volumes of citrate buffer solution pH 3.2 was used as the mobile phase with a flow rate of 1.0 ml per minute and a detection wavelength of 254 nm. The HPLC method was validated in terms of specificity, linearity, accuracy, precision, limit of detection and limit of quantification. The assay ranges are from about LOQ value to 120 percent of the limit of related substances in IBT material (0.2437 µg/ml to 2.9241 µg/ml with IAT and 0.1355 µg/ml to 3.2527 µg/ml with TEZ). All results proved the method suitable for the intended application.
Nghiên cứu xây dựng quy trình phân lập và tinh chế tenuifolin từ dược liệu Viễn chí (Radix polygalae) làm nguyên liệu thiết lập chất chuẩn
In China and Vietnam, Radix polygalae has been widely used as a traditional herbal. With reference to the quality of Radix polygalae, its content of tenuifolin quantified by HPLC/DAD is specified to be not less than 2.0 %. For the quality control of Radix polygalae, the establishment of tenuifolin as an affordable-price reference standard is prerequisite in Vietnam. In this study, 1.3 g of tenuifolin was isolated and purified from 500 g of Radix polygalae. The structure of tenuifolin was confirmed by 1H, 13C-NMR, HR-MS, IR, UV-VIS…, as compared to the corresponding spectra of tenuifolin reference standard. The content of tenuifolin in our purified samples was determined to be of 92.5 % by HPLC-DAD analysis.
Xây dựng và thẩm định phương pháp xác định dư lượng một số chất gây nghiện trong bùn thải bằng LCMS/MS
Locating the ‘Golden Triangle’ with a long border and ¾ terrain of mountains, the number of seized drugs of Vietnam raised significantly. In the last decade, WBE emerges as an effective tool for providing spatio-temporal variations of drug use among population, especially in areas where surveys are not effective. To use this method, we should analyze the residue of drug and its metabolites in environment. In Vietnam, some studies aimed to analyze illicit drugs in wasterwater, however, in the sewage sludge, there are no study have been conducted. In this study, we aimed to develop a method to analyze Amphetamine, Methamphetamine, MDMA and Ketamine in the sewage sludge by SPE extraction before injected to LC-MS/MS. The validaton results show that the method had good sensitivity (LOQ from 0.1 - 0.5 ppb); good linear range (from 0.125 ppb to 15 ppb); accuracy ranges from 70.0 to 114.5 %; good repeatability (RSD % values 0.68 - 7.25 %). The developed method can be applied to analyze theses illicit drugs in sewage sludge of Vietnam.
Xây dựng phương pháp định lượng azithromycin trong nền viên nén có thành phần xác định bằng phương pháp quang phổ hồng ngoại phản xạ (FTIR-ATR)
An FTIR-ATR based method was developed for quantitation of azithromycin in tablet powder with known composition. The method employed spectra of reference mixture containing from 35 % to 95 % azithromycin (w/w) recorded in wavenumber zone from 400 cm-1 to 2000 cm-1 and normalized at wavenumber 1720 cm-1 to build PLS assay model using 4 factors. The method was validated according to current international requirements on performance of analytical method, and was proved as suitable for intended purpose.