Skip to Content
Merck
  • The Fantastic Four: A plug 'n' play set of optimal control pulses for enhancing NMR spectroscopy.

The Fantastic Four: A plug 'n' play set of optimal control pulses for enhancing NMR spectroscopy.

Journal of magnetic resonance (San Diego, Calif. : 1997) (2013-01-22)
Manoj Nimbalkar, Burkhard Luy, Thomas E Skinner, Jorge L Neves, Naum I Gershenzon, Kyryl Kobzar, Wolfgang Bermel, Steffen J Glaser
ABSTRACT

We present highly robust, optimal control-based shaped pulses designed to replace all 90° and 180° hard pulses in a given pulse sequence for improved performance. Special attention was devoted to ensuring that the pulses can be simply substituted in a one-to-one fashion for the original hard pulses without any additional modification of the existing sequence. The set of four pulses for each nucleus therefore consists of 90° and 180° point-to-point (PP) and universal rotation (UR) pulses of identical duration. These 1ms pulses provide uniform performance over resonance offsets of 20kHz ((1)H) and 35kHz ((13)C) and tolerate reasonably large radio frequency (RF) inhomogeneity/miscalibration of ±15% ((1)H) and ±10% ((13)C), making them especially suitable for NMR of small-to-medium-sized molecules (for which relaxation effects during the pulse are negligible) at an accessible and widely utilized spectrometer field strength of 600MHz. The experimental performance of conventional hard-pulse sequences is shown to be greatly improved by incorporating the new pulses, each set referred to as the Fantastic Four (Fanta4).

MATERIALS
Product Number
Brand
Product Description

Sigma-Aldrich
Ammonium formate, SAJ first grade, ≥95.0%
Supelco
Calcium formate, Standard for quantitative NMR, TraceCERT®, Manufactured by: Sigma-Aldrich Production GmbH, Switzerland
Sigma-Aldrich
Ammonium formate, ≥99.995% trace metals basis
Sigma-Aldrich
Ammonium formate, BioUltra, ≥99.0% (calc. based on dry substance, NT)
Supelco
Ammonium formate, eluent additive for LC-MS, LiChropur, ≥99.0%
Sigma-Aldrich
Thallium(I) formate, 97%
Sigma-Aldrich
Cesium formate, 98%
Sigma-Aldrich
Calcium formate, BioUltra, ≥99.0% (T)
Sigma-Aldrich
Ammonium formate, reagent grade, 97%
Sigma-Aldrich
7-Hydroxycitronellal, Odorant used in allergy studies
Supelco
Ammonium formate solution, 10 mM in H2O, suitable for HPLC
Sigma-Aldrich
Hydroxycitronellal, ≥95%, FCC, FG
Sigma-Aldrich
Sodium formate-13C, 99 atom % 13C
Sigma-Aldrich
Sodium formate, 99.998% trace metals basis
Sigma-Aldrich
Formic acid, ≥95%, FCC, FG
Sigma-Aldrich
Formic acid solution, BioUltra, 1.0 M in H2O
Sigma-Aldrich
Ammonium formate solution, BioUltra, 10 M in H2O
Sigma-Aldrich
Potassium formate, ReagentPlus®, 99%
Sigma-Aldrich
Potassium formate, BioUltra, ≥99.0% (NT)
Sigma-Aldrich
Formic acid, JIS special grade, ≥98.0%
Sigma-Aldrich
Sodium formate, BioUltra, ≥99.0% (NT)
Sigma-Aldrich
Sodium formate, reagent grade, 97%
Sigma-Aldrich
Formic acid, ACS reagent, ≥96%
Sigma-Aldrich
Formic acid, puriss., meets analytical specifications of DAC, FCC, 98.0-100%
Sigma-Aldrich
Sodium formate, ACS reagent, ≥99.0%
Sigma-Aldrich
Formic acid, reagent grade, ≥95%
Sigma-Aldrich
Formic acid, puriss. p.a., ACS reagent, reag. Ph. Eur., ≥98%
Sigma-Aldrich
Formic acid, ACS reagent, ≥88%