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Determination of apramycin in oral soluble powder by a HPLC method using pre-column derivatization with o-phthalaldehyde and UV detection
Antunes, Elisabete de Almeida Barbosa;Louren?o, Felipe Rebello;Pinto, Terezinha de Jesus Andreoli;
Brazilian Journal of Pharmaceutical Sciences , 2011, DOI: 10.1590/S1984-82502011000200007
Abstract: a high-performance liquid chromatographic method employing pre-column derivatization with o-phthalaldehyde (opa) and 2-mercaptoacetic acid was developed for the determination of apramycin, an aminoglycoside antibiotic used in veterinary medicine, in the oral soluble powder form. the chromatographic separation was done by ion-pair hplc using a c18 reversed-phase column, synergy hydro (150 mm x 4.6 mm x 4 μm) and mobile phase composed of 0.005 mol/l sodium octanosulfonate in a mixture of acetonitrile: water: acetic acid (45:55:2) (v/v/v) with a flow rate of 1.0 ml/min; the uv detector was operated at 332 nm. the developed method was validated according to official compendia guidelines, having demonstrated robustness, selectivity and linearity for the concentration range of 0.02 to 0.05 mg/ml, precision (with rsd < 2.0% both for intra and inter-day precision) accuracy (average recuperation of 99.33%) and detectivity (quantification and detection limits of 0.08 and 0.02 μg/ml, respectively). three batches of commercial apramycin oral soluble powder were analyzed by both the proposed method and the official microbiological method, where all the results obtained were in the acceptable range (95% to 105% of labeled value of apramycin). both methods were statistically compared by the t test, which yielded no significant differences (α = 0.05) thereby confirming the equivalence of the methods.
Enantioresolution of a Series of Chiral Benzyl Alcohols by HPLC on a Dinitrobenzoylphenylglycine Stationary Phase after Achiral Pre-Column Derivatization*  [PDF]
Svilen P. Simeonov, Anton P. Simeonov, Aleksandar R. Todorov, Vanya B. Kurteva
American Journal of Analytical Chemistry (AJAC) , 2010, DOI: 10.4236/ajac.2010.11001
Abstract: High performance liquid chromatography method for the separation of a series of chiral benzyl alcohols on N-(3,5-dinitrobenzoyl)-D-phenylglycine stationary phase (Macherey Nagel, Chiral-2) after pre-column achiral derivatization was developed. Cheap and easy available aromatic acid chlorides were used as derivatization agents. Good to excellent separations of the enantiomers were achieved in all cases in relatively short analytical runs. It was shown that the enantiorecognition depends on the substituents both in the starting alcohol and in the acid chloride. The method presents an efficient alternative to the direct analyses on polysaccharide and cyclodextrine-derived stationary phases.
Determination of Glutamine in Intestinal Mucosa by Pre Column Derivatization/Reversed Phase High Performance Liquid Chromatography with Fluorescence Detection
反相高效液相色谱柱前衍生荧光法测定肠粘膜中的谷氨酰胺

G Shang,Y Jiang,H Tang,Y Fan,S Wang,G Dong,J Wang,
尚刚伟
,蒋永培,汤海峰,樊亚萱,王胜春,董光龙,王俊义

色谱 , 1997,
Abstract: A high performance liquid chromatographic pre-column derivatization method with fluorescence detection for the analysis of glutamine (Gln) in rat intestinal mucosa is presented. Gln was derivatized with o-phthalaldehyde and 3-mercaptopropionic acid under an alkaline condition and separated by reversed-phase liquid chromatography on a Lichrosorb RP18 column (150 mm x 4.6 mm i.d., 5 microm). The mobile phase was consisted of 50 mmol/L phosphate buffer (pH 7.0)-acetonitrile (94:6, V/V) with a flow rate of 2.0 mL/min. The excited and emitted wavelength were selected at 230 nm and 389 nm respectively. The volume ratio of samples and derivatization reagent solution was 4:1 (V/V). The detection limit of Gln was 25 micromol/L (S/N= 3.5) and the regression equation was A = 16.9405C + 179.9339, r = 0.9996 at the linear range of 50-3200 micromol/L. The day-to-day deviation was 6.97% (n = 3) and the retention time of Gln was 3.158 min. This method is rapid, simple and highly sensitive, and has been applied to the determination of Gln in intestinal mucosa.
Determination of Monensin Residue in Chicken by HPLC with Post Column Derivatization
柱后衍生高效液相色谱法测定鸡肉中莫能菌素残留量

Chen Xiaomei,Shi Xuxia,
陈笑梅
,施旭霞

色谱 , 1999,
Abstract: The monensin residue was extracted from the tissue by homogenization with methanol-water and the extract was filtered and partitioned with dichloromethane. The dichloromethane extract is concentrated and clean up by passing through a silica gel cartridge. The analyte on the cartridge is then eluted with dichloromethane-methanol. The eluate is collected and evaporated to dryness. The residue is dissolved and made to a definite volume with 1 mL methanol and the solution is used for post-column derivatization-HPLC determination. Monensin is separated on mu-Bondapak C18 column (3.9 mm i.d. x 300 mm) with methanol-water-phosphoric acid as a mobile phase and the flow rate was 0.7 mL/min. The eluted monensin was reacted with vaniline under acidic and heated condition in post-column derivatization system then detected at 520 nm and quantitated by external standard method. The derivatization reagent consisted of 20 mL concentrated sulfuric acid, 950 mL methanol and 30 g vaniline. The flow rate was 0.7 mL/min. The reactor was a stainless steel coil (300 cm x 1 mm i.d.) set in a 90 degrees C oven. The response values was linear between 20-200 ng. The recovery was 88.1%-101.3%. The coefficient of variation was 0.1%-0.73%.
Determination of Rofecoxib in Serum with Pre-column Derivatization and Fluorescence Detection  [PDF]
Mohsen Amini,Morteza Pirali-Hamedani,Hossein Ali Ebrahimi,Majid Darabi
International Journal of Pharmacology , 2005,
Abstract: A HPLC method for determination of rofecoxib in human serum was presented. The method is based on pre-column derivatization of analyte to a phenanthrene derivative of drug. Rofecoxib and internal standard were extracted from serum using liquid-liquid extraction. Upon exposure to UV light, drug was found to undergo a phtocyclization reaction giving a species with high absorbance. Validation of the method has been studied in the concentration range of 2-100 ng mL-1.
Simple HPLC-Fluorescence Determination of Raspberry Ketone in Fragrance Mist after Pre-Column Derivatization with 4-Hydrazino-7-nitro-2,1,3-benzoxadiazole  [PDF]
Yasuhiko Higashi
Journal of Analytical Sciences, Methods and Instrumentation (JASMI) , 2016, DOI: 10.4236/jasmi.2016.62006
Abstract: Raspberry ketone {RK, 4-(4-hydroxyphenyl)butan-2-one} is a natural compound contained in raspberry, and is added to cosmetics for skin whitening. It is very important to measure the RK level in cosmetics for quality assessment, since RK structurally resembles 4-(4-hydroxyphenyl)-2-butanol, which causes leukoderma on consumers’ skin. Here, we present a simple HPLC-fluorescence method for determination of RK in a fragrance mist by pre-column derivatization with 4-hydrazino-7-nitro-2,1,3-benzoxadiazole hydrazine (NBD-H), which reacts with the carbonyl group of RK. The NBD-RK derivative was eluted from a reversed-phase ODS column, and detected with excitation at 470 nm and emission at 550 nm. The retention time of NBD-RK derivative obtained by reaction with NBD-H at 80°C for 20 min was 10.3 min. The standard curve was linear in the range of 0.2 to 10 μg/mL, with a correlation coefficient (r2) value of 0.9980. The lower limit of detection was 0.018 μg/mL (absolute amount of 1.8 pmol). The coefficients of variation were less than 8.1%. The content of RK in fragrance mist (1.00 mL) was 1.18 ± 0.07 mg (range: 1.12 to 1.28 mg, n = 5). Recovery tests were satisfactory (83.9% ± 3.9%; range: 79.6 to 88.8%, n = 5).
柱前衍生RP-HPLC法测定狗尾草种子氨基酸含量
Determination of amino acids in seeds of Setaria viridis (L.) Beauv. by pre-column derivatization RP-HPLC
 [PDF]

,,唐国胜,侯莹莹,
- , 2015,
Abstract: 【目的】采用柱前衍生反相高效液相色谱(RP-HPLC)法检测狗尾草种子中游离氨基酸和水解氨基酸含量,为阐明其应用价值提供支撑。【方法】制备狗尾草种子的水解氨基酸样品溶液和游离氨基酸样品溶液,以异硫氰酸苯酯和三乙胺进行柱前衍生,建立RP-HPLC法,检测方法的精密性、稳定性、重复性。利用RP-HPLC法,采用梯度洗脱方法,检测狗尾草种子中游离氨基酸和水解氨基酸含量。【结果】21种氨基酸的检测浓度线性范围为0.001 9~2.700 0 μmol/mL,相关系数R2均≥0.999 0。21种游离氨基酸的平均加样回收率在87.50%~100.20%,相对标准偏差(RSD)在0.82%~2.46%;水解氨基酸的平均加样回收率在91.10%~100.21%,RSD 在0.52%~2.08%。必需氨基酸和半必需氨基酸在狗尾草21种游离氨基酸和水解氨基酸中均含有,但水解后色氨酸、天冬酰胺、组胺酰胺遭到了破坏,含量较低。【结论】建立的氨基酸测定方法稳定、快速、精密度高、线性范围宽,适合狗尾草种子中游离氨基酸和水解氨基酸的含量测定。狗尾草种子中含有丰富的游离和水解氨基酸。
【Objective】This study aimed to establish a method for determinating the contents of free and hydrolyzed amino acids from seeds of Setaria viridis (L.) Beauv.by pre-column derivatization RP HPLC.【Method】The sample solution including free and hydrolyzed amino acids from the seeds of Setaria viridis (L.) Beauv was prepared before being derived with phenyl isothiocyanate and triethylamine,and detected by HPLC.The precision,stability,and repeatability were detected before gradient elution chromatography was applied to determine the contents of free and hydrolyzed amino acids.【Result】The 21 amino acids had good linearity in the range of 0.001 9-2.700 0 μmol/mL with correlation coefficients all over 0.999 0.The average recovery of free amino acids was 87.50%-100.20% (RSD=0.82%-2.46%).The average recovery of total amino acids was 91.10%-100.21%(RSD=0.52%-2.08%).There were essential amino acids and semi essential amino acids for human in seeds of Setaria viridis (L.) Beauv.But tryptophan,asparagine,and histamine amide were compromised after hydrolysis.【Conclusion】The established method was sensitive,accurate,reproducible,and reliable for determination of amino acids.Both free and hydrolyzed amino acids were rich in seeds of Setaria viridis (L.) Beauv
Improved Method for Determination of Raspberry Ketone in Fragrance Mist by HPLC-Fluorescence Analysis after Pre-Column Derivatization with 4-(N,N-Dimethylaminosulfonyl)-7-(N-chloroformylmethyl-N-methylamino)-2,1,3-benzoxadiazole  [PDF]
Yasuhiko Higashi
Journal of Analytical Sciences, Methods and Instrumentation (JASMI) , 2018, DOI: 10.4236/jasmi.2018.82002
Abstract:

Raspberry ketone {RK, 4-(4-hydroxyphenyl)butan-2-one} is structurally resembles 4-(4-hydroxyphenyl)-2-butanol, which causes leukoderma on consumers’ skin. Therefore, it is important to measure in cosmetics for quality assessment. Very recently, an HPLC-fluorescence method for determination of RK in a fragrance mist by pre-column derivatization with 4-hydrazino-7-nitro-2,1,3-benzoxadiazole hydrazine was established. However, the derivatization conditions (80°C, 20 min) were severe. In this study, an improved pre-column derivatization with 4-(N,N-dimethylaminosulfonyl)-7-(N-chloro-formylmethyl-N-methylamino)-2,1,3-benzoxadiazole (DBD-COCl) is presented by HPLC-fluorescence method for determination of RK. The DBD-CO-RK derivative was eluted from a reversed-phase ODS column, and detected with excitation at 440 nm and emission at 543 nm. Derivatization was performed at room temperature for 3 min. The retention time of DBD-CO-RK derivative was 16.8 min. The standard curve was linear in the range of 0.05 to 2.5 μg/mL, with a correlation coefficient (r2) value of 0.9988. The lower limit of detection was 0.01 μg/mL (absolute amount of 0.3 pmol). The coefficients of variation were less than 10.0%. The content of RK in fragrance mist (1.00 mL) was 1.20 ± 0.08 mg (range, 1.10 to 1.31 mg,

Development of Simultaneous HPLC-Fluorescence Assay of Phenol and Chlorophenols in Tap Water after Pre-Column Derivatization with 3-Chlorocarbonyl-6,7-dimethoxy-1- methyl-2(1H)-quinoxalinone  [PDF]
Yasuhiko Higashi
Detection (Detection) , 2016, DOI: 10.4236/detection.2016.41003
Abstract: Chlorophenols (2-chlorophenol, 4-chlorophenol, 2,4-dichlorophenol, 2,6-dichlorophenol and 2,4, 6-trichlorophenol) may be presented in natural waters or drinking water as a result of disinfection processes involving chlorination, or as contaminants derived from domestic products, industrial operations and agricultural chemicals. A previous HPLC-UV method for determination of phenol and five chlorophenols in tap water using 4-fluoro-7-nitro-2,1,3-benzoxadiaole as a UV labeling reagent shows limited sensitivity. Here, we present an improved HPLC-fluorescence detection method for simultaneous determination of phenol and the above chlorophenols in tap water after pre-column derivatization with 3-chlorocarbonyl-6,7-dimethoxy-1-methyl-2(1H)-quino- xalinone (DMEQ-COCl), using a short, narrow column (50 × 2.1 mm i.d., packed with 5 μm particles of C18 material) to improve the sensitivity. Standard samples containing the compounds are derivatized with DMEQ-COCl in borate buffer (pH 9.0) at room temperature for 3 mins. The response is linear in the concentration range of 0.01 - 0.05 to 0.5 mg/L with r2 values ≥0.9967 for all compounds. The lower limits of detection are 0.001 to 0.008 mg/L, and the coefficients of variation are less than 8.8%. The recovery values from tap water spiked with standard samples are satisfactory. The present method is suitable for examining whether or not tap water samples are contaminated with phenol and chlorophenols in excess of regulatory values.
Determination of alliin and its related substances in garlic using pre-column derivatization and reversed-phase high performance liquid chromatography
AQC柱前衍生化RP-HPLC法测定蒜氨酸及其有关物质的含量

YUAN Yaozuo,HANG Taijun,JI Yu,ZHANG Zhengxing,
袁耀佐
,杭太俊,纪宇,张正行

色谱 , 2008,
Abstract: A reversed-phase high performance liquid chromatographic method with pre-column derivatization for the determination of alliin and its related substances, which are the precursors of garlic's active components, was established. Alliin was derivatized with 6-aminoquinolyl-N-hydroxysuccinimicly carbamate (AQC). The reaction of derivatization was very fast and the derivative was stable. The analysis was carried out on a Kromasil C18 column (250 mm x 4.6 mm, 5 microm) with a gradientelution and detection at 248 nm. The mobile ph ase consisted of 0.1% acetamide (0.03% acetic acid) (A) and the mixture of water and acetonitrile (40: 60, v/v) (B), and the flow rate was set at 1.0 mL/min. The linear calibration was found for alliin within the range of 1.171 9 -1 500 microg/mL (r = 0.999 8). The inter-day and intra-day precision were good with relative standard deviation (RSD) less than 1.8% (n = 5). The recovery was 99.1% with the RSD of 1.9%. The limit of detection was 0.15 microg/mL. The method established is accurate, simple and rapid and suitable for the determination of alliin and related substances.
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