Use of Hybrid Capillary Tube Apparatus on 400 MHz NMR for Quantitation of Crucial Low-Quantity Metabolites Using aSICCO Signal.

نویسندگان

  • Ranjeet Tiwari
  • Deepak Ahire
  • Hemantha Kumar
  • Sarmistha Sinha
  • Siddheshwar Kisan Chauthe
  • Murali Subramanian
  • Ramaswamy Iyer
  • Ramakanth Sarabu
  • Lakshmikant Bajpai
چکیده

Metabolites of new chemical entities can influence safety and efficacy of a molecule and often times need to be quantified in preclinical studies. However, synthetic standards of metabolites are very rarely available in early discovery. Alternate approaches such as biosynthesis need to be explored to generate these metabolites. Assessing the quantity and purity of these small amounts of metabolites with a nondestructive analytical procedure becomes crucial. Quantitative NMR becomes the method of choice for these samples. Recent advances in high-field NMR (>500 MHz) with the use of cryoprobe technology have helped to improve sensitivity for analysis of small microgram quantity of such samples. However, this type of NMR instrumentation is not routinely available in all laboratories. To analyze microgram quantities of metabolites on a routine basis with lower-resolution 400 MHz NMR instrument fitted with a broad band fluorine observe room temperature probe, a novel hybrid capillary tube setup was developed. To quantitate the metabolite in the sample, an artificial signal insertion for calculation of concentration observed (aSICCO) method that introduces an internally calibrated mathematical signal was used after acquiring the NMR spectrum. The linearity of aSICCO signal was established using ibuprofen as a model analyte. The limit of quantification of this procedure was 0.8 mM with 10 K scans that could be improved further with the increase in the number of scans. This procedure was used to quantify three metabolites-phenytoin from fosphenytoin, dextrophan from dextromethorphan, and 4-OH-diclofenac from diclofenac-and is suitable for minibiosynthesis of metabolites from in vitro systems.

برای دانلود رایگان متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Molecular weight of low molecular weight heparins by 13C nuclear magnetic resonance spectroscopy.

Heparin and low molecular weight heparins are polydisperse polysaccharides with a degree of polymerization ranging from 4 to approximately 40. The determination of their average molecular weights has traditionally relied on size exclusion chromatography involving the use of oligosaccharides of known size and molecular weight as standards. 13C NMR spectroscopy is applied for the first time to ob...

متن کامل

Validation of isolated metabolites from drug metabolism studies as analytical standards by quantitative NMR.

In discovery and development, having a qualified metabolite standard is advantageous. Chemical synthesis of metabolite standards is often difficult and expensive. As an alternative, biological generation and isolation of metabolites in the nanomole range are readily feasible. However, without an accurately defined concentration, these isolates have limited utility as standards. There is a signi...

متن کامل

Microwave Irradated Synthesis, Characterization and Evaluation for their Antibacterial and Larvicidal Activities of some Novel Chalcone and Isoxazole Substituted 9-Anilino Acridines

Melting points were obtained on Veego VMP-1 apparatus in open capillary tubes and are uncorrected. The reactions were monitored by TLC on silica gel thin layer plates. Compounds were analyzed for C, H, N and analytical results obtained for these elements were within ±0.5% of the calculated values for the formula shown. IR spectra were obtained using a Perkin Elmer spectrum-2 FT-IR spectrometer....

متن کامل

Evaluation of Acetonitrile Deproteinisation of the Serum Samples for the Analysis of Drugs in Serum Using Capillary Zone Electrophoresis

Deproteinisation with acetonitrile (along with methanol or other reagents) is a useful and rapid technique in analysis of drugs or their metabolites in human serum. In this paper application of this simple technique in biopharmaceutical analysis using capillary electrophoresis (CE) is evaluated. Some drugs with different ionic and protein binding properties were selected and dissolved in human ...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

عنوان ژورنال:
  • Drug metabolism and disposition: the biological fate of chemicals

دوره 45 12  شماره 

صفحات  -

تاریخ انتشار 2017