The synthesis and purification of modified antisense of igodeoxyriboucleotides (MAO ) are des cribed. A new oligonucleotide purification method and a novel activating agent, dimethyl sulfoxide, for thecondensation rea...The synthesis and purification of modified antisense of igodeoxyriboucleotides (MAO ) are des cribed. A new oligonucleotide purification method and a novel activating agent, dimethyl sulfoxide, for thecondensation reaction are used. EDTA has been attached covalently to the 5’ end of the oligodeoxyribonucleotides sequence via an ethylenediamine linker in basic triethylammonium solution, then chelated withthe metal ions such as Fe(Ⅱ), Co(Ⅱ) or Cu(Ⅱ). High performance liquid chromatorgaphy is used to separate and purify this kind of MAO, using double mobile phase, triethylammonium acetate and acetonitrile. Byusing this routine chemical synthesis method, EDTA can be linked to the 5’ terminus of oligodeoxyribonucleotedes of any desired length and sequence, forming chimeric MAOs.展开更多
Liquid-liquid extraction-thin layer chromatography (LLE-TLC) has been a common and routine combined method for detection of drugs in biological materials. Solid-phase extraction (SPE) is gradually replacing the tr...Liquid-liquid extraction-thin layer chromatography (LLE-TLC) has been a common and routine combined method for detection of drugs in biological materials. Solid-phase extraction (SPE) is gradually replacing the tra- ditional LLE method. High performance thin layer chromatography (HPTLC) has several advantages over TLC. The present work studied the higher efficiency of a new SPE-HPTLC method over that of a routine LLE-TLC method, in extraction and detection of urinary morphine. Fifty-eight urine samples, primarily identified as mor- phine-positive samples by a strip test, 'were re-screened by LLE-TLC and SPE-HPTLC. The results of LLE-TLC and SPE-HPTLC were then compared with each other. The results showed that the SPE-HPTLC detected 74% of total samples as morphine-positive samples whereas the LLE-TLC detected 48% of the same samples. We further discussed the effect of codeine abuse on TLC analysis of urinary morphine. Regarding the importance of morphine detection in urine, the present combined SPE-HPTLC method is suggested as a replacement method for detection of urinary morphine by many reference laboratories.展开更多
该文建立液相色谱-稳定同位素比值质谱联用(liquid chromatography-stable isotope ratio mass spectrometry,LC-IRMS)检测抗坏血酸δ^(13)C值的分析方法,用于鉴别针叶樱桃粉中抗坏血酸天然来源的真实性。样品中抗坏血酸经液相色谱在线...该文建立液相色谱-稳定同位素比值质谱联用(liquid chromatography-stable isotope ratio mass spectrometry,LC-IRMS)检测抗坏血酸δ^(13)C值的分析方法,用于鉴别针叶樱桃粉中抗坏血酸天然来源的真实性。样品中抗坏血酸经液相色谱在线分离纯化,优化后色谱条件为:Syncronis C18(250 mm×4.6 mm,5μm)色谱柱,流动相为水-pH 2的硫酸溶液(90∶10,体积比),流速0.250 mL/min,色谱柱温度30℃,进样量10μL,通过LC-IsoLink实现目标物全部氧化为CO_(2)气体,最终以气态形式进入稳定同位素质谱仪,直接检测样品中抗坏血酸的δ^(13)C,该方法结果稳定、准确。分别测定了7个合成来源的维生素C片和19个针叶樱桃粉,结果表明,天然来源抗坏血酸δ^(13)C值为-25.00‰~-22.01‰,合成来源抗坏血酸δ^(13)C值为-11.74‰~-10.28‰,两者分布显著性差异,该方法可用于抗坏血酸产品标识的真实性鉴别研究。展开更多
A simple and sensitive high performance liquid chromatography method using fluorescence detection (HPLC- FLD) and a one-step single solvent extraction for the determination of prazosin(PZS) in dog plasma is develo...A simple and sensitive high performance liquid chromatography method using fluorescence detection (HPLC- FLD) and a one-step single solvent extraction for the determination of prazosin(PZS) in dog plasma is developed and validated. After extraction with ether, the chromatographic separation of PZS is carried out using a reverse phase C18 column ( 150 mm ×4.6 mm, 5 μm) with a mobile phase of 30% acetonitrile and 70% acetic acid-sodium acetate buffer solution (pH = 3.6) and quantified by fluorescence detection operated with an excitation wavelength of 258 nm and an emission wavelength of 387 nm. The flow rate of the mobile phase is 1.0 mL/min and the retention time of PZS and the internal standard is found to be 4. 4 and 5. 8 rain, respectively. The calibration curve is linear within a concentration range from 1.0 to 1 000.0 ng/mL ( P 〉 0. 998). The limit of detection is 0.4 ng/mL. The inter-day coefficient of variation (COV) of the calibration standards is below 5.0% and the mean accuracy is in the range from 92. 7% to 104. 2%. Moreover, by analyzing quality control plasma samples for three days, the results show that the method is precise and accurate, for the intra- and inter- day COV within 10% and the accuracy from 95.9% to 112.7%. The developed and validated method is successfully applied to phannacokinetic study for the preclinical evaluation of a new peroral PZS-sulfobutyl ether beta-cyclodextrin (PZS-SBE-β-CD) inclusion complex tablets (test preparation), which demonstrates that the test preparation released PZS is conducted in a slow and controlled way, and the relative bioavailability of the test preparation is found to be 105.0%.展开更多
文摘The synthesis and purification of modified antisense of igodeoxyriboucleotides (MAO ) are des cribed. A new oligonucleotide purification method and a novel activating agent, dimethyl sulfoxide, for thecondensation reaction are used. EDTA has been attached covalently to the 5’ end of the oligodeoxyribonucleotides sequence via an ethylenediamine linker in basic triethylammonium solution, then chelated withthe metal ions such as Fe(Ⅱ), Co(Ⅱ) or Cu(Ⅱ). High performance liquid chromatorgaphy is used to separate and purify this kind of MAO, using double mobile phase, triethylammonium acetate and acetonitrile. Byusing this routine chemical synthesis method, EDTA can be linked to the 5’ terminus of oligodeoxyribonucleotedes of any desired length and sequence, forming chimeric MAOs.
文摘Liquid-liquid extraction-thin layer chromatography (LLE-TLC) has been a common and routine combined method for detection of drugs in biological materials. Solid-phase extraction (SPE) is gradually replacing the tra- ditional LLE method. High performance thin layer chromatography (HPTLC) has several advantages over TLC. The present work studied the higher efficiency of a new SPE-HPTLC method over that of a routine LLE-TLC method, in extraction and detection of urinary morphine. Fifty-eight urine samples, primarily identified as mor- phine-positive samples by a strip test, 'were re-screened by LLE-TLC and SPE-HPTLC. The results of LLE-TLC and SPE-HPTLC were then compared with each other. The results showed that the SPE-HPTLC detected 74% of total samples as morphine-positive samples whereas the LLE-TLC detected 48% of the same samples. We further discussed the effect of codeine abuse on TLC analysis of urinary morphine. Regarding the importance of morphine detection in urine, the present combined SPE-HPTLC method is suggested as a replacement method for detection of urinary morphine by many reference laboratories.
基金Pre-Research Foundation for the National Natural Science Foundation of Southeast University(No.9225000007)Suzhou Science and Technology Development Projects(No.YJS0948)
文摘A simple and sensitive high performance liquid chromatography method using fluorescence detection (HPLC- FLD) and a one-step single solvent extraction for the determination of prazosin(PZS) in dog plasma is developed and validated. After extraction with ether, the chromatographic separation of PZS is carried out using a reverse phase C18 column ( 150 mm ×4.6 mm, 5 μm) with a mobile phase of 30% acetonitrile and 70% acetic acid-sodium acetate buffer solution (pH = 3.6) and quantified by fluorescence detection operated with an excitation wavelength of 258 nm and an emission wavelength of 387 nm. The flow rate of the mobile phase is 1.0 mL/min and the retention time of PZS and the internal standard is found to be 4. 4 and 5. 8 rain, respectively. The calibration curve is linear within a concentration range from 1.0 to 1 000.0 ng/mL ( P 〉 0. 998). The limit of detection is 0.4 ng/mL. The inter-day coefficient of variation (COV) of the calibration standards is below 5.0% and the mean accuracy is in the range from 92. 7% to 104. 2%. Moreover, by analyzing quality control plasma samples for three days, the results show that the method is precise and accurate, for the intra- and inter- day COV within 10% and the accuracy from 95.9% to 112.7%. The developed and validated method is successfully applied to phannacokinetic study for the preclinical evaluation of a new peroral PZS-sulfobutyl ether beta-cyclodextrin (PZS-SBE-β-CD) inclusion complex tablets (test preparation), which demonstrates that the test preparation released PZS is conducted in a slow and controlled way, and the relative bioavailability of the test preparation is found to be 105.0%.