Related Experiment Video
Updated: May 12, 2025

Subcloning Plus Insertion SPI - A Novel Recombineering Method for the Rapid Construction of Gene Targeting Vectors
Published on: January 8, 2015
Single and double-selective split-inversion pulse and recovery (SIP-R) sequences for targeted T1 relaxation
Zachary G Mayes1, Yugandhara A M Eriyagama1, Lingyu Chi1
1Department of Chemistry, Missouri University of Science and Technology, United States.
Split-Inversion-Pulse and Recovery (SIP-R) NMR methods were adapted for frequency selectivity. These new techniques accurately measure relaxation times and differentiate water states in polymer hydrogels.
Area of Science:
- Nuclear Magnetic Resonance (NMR) Spectroscopy
- Materials Science
- Physical Chemistry
Background:
- Split-Inversion-Pulse and Recovery (SIP-R) is an NMR technique for spin-lattice relaxation measurements.
- Its robust decay-to-zero profile aids in extracting multiple relaxation times via inverse Laplace transformation (ILT).
Purpose of the Study:
- To introduce and evaluate frequency-selective adaptations of the SIP-R NMR method.
- To assess the utility of these selective methods for analyzing relaxation behavior and molecular interactions in complex systems like polymer hydrogels.
Main Methods:
- Development of single- and double-frequency-selective SIP-R pulse sequences.
- Application of non-selective and selective SIP-R methods to ethanol-D2O solutions and polymer hydrogels.
- Analysis of relaxation times and Nuclear Overhauser Effect (NOE) data.
Main Results:
- Both single- and double-selective SIP-R methods yielded comparable relaxation times to non-selective SIP-R in ethanol-D2O.
- The double-selective method introduced potential artifacts attributed to pulse duration.
- Non-selective SIP-R successfully quantified free (95%) versus bound (5%) water in a polymer hydrogel.
- Selective SIP-R variants indicated strong NOE effects between water and polymer amide resonances.
Conclusions:
- Frequency-selective SIP-R methods are viable adaptations for targeted relaxation studies.
- These techniques can differentiate water populations and probe water-polymer interactions in hydrogels.
- Careful consideration of pulse parameters is necessary to avoid artifacts in selective NMR experiments.
More Related Videos
Related Concept Videos
Double Resonance Techniques: Overview
Spin decoupling is usually achieved by...
NMR Spectrometers: Radiofrequency Pulses and Pulse Sequences
Insensitive Nuclei Enhanced by Polarization Transfer (INEPT)
Conservative Site-specific Recombination and Phase Variation
The recognition sites for Cre recombinase called LoxP...
Next-generation Sequencing
Next-Generation Sequencing Methods
Although all next-generation methods use different technologies, they all share a set of standard features....
RNA-seq
Before the discovery of RNA-seq, microarray-based methods and Sanger sequencing were used for transcriptome analysis. However, while...

