Polymer Liquid Adsorption Chromatography
Copolymer analysis is challenging because at least two distributions can be present simultaneously: the molar mass distribution (MMD) and the chemical composition distribution (CCD).
While there are molar mass sensitive detectors for the determination of the MMD of homopolymers, the applicability of these detectors for copolymers suffers from potential co-elution in GPC/SEC and (in case of lightscattering) from the dependence of the dn/dc on composition. In addition, these detectors do not provide any insight into the CCD.
The CCD can be determined using several techniques including dual detection, which was discussed in the first chapter of this eBook. In this case, GPC/SEC separation based on the size (hydrodynamic volume) is applied and the CCD of, for example, block copolymers is determined using at least two different detectors.
The Next Frontier for Mass Spectrometry: Maximizing Ion Utilization
January 20th 2025In this podcast, Daniel DeBord, CTO of MOBILion Systems, describes a new high resolution mass spectrometry approach that promises to increase speed and sensitivity in omics applications. MOBILion recently introduced the PAMAF mode of operation, which stands for parallel accumulation with mobility aligned fragmentation. It substantially increases the fraction of ions used for mass spectrometry analysis by replacing the functionality of the quadrupole with high resolution ion mobility. Listen to learn more about this exciting new development.
Liquid Chromatography to Analyze Vitamin D Proteins in Psoriasis Patients
January 21st 2025Can a protein involved in delivering Vitamin D to target tissues have an altered serum profile in psoriasis patients with cardiovascular disease? Researchers used liquid chromatography (LC) to help find out.
The Complexity of Oligonucleotide Separations
January 9th 2025Peter Pellegrinelli, Applications Specialist at Advanced Materials Technology (AMT) explains the complexity of oligonucleotide separations due to the unique chemical properties of these molecules. Issues such as varying length, sequence complexity, and hydrophilic-hydrophobic characteristics make efficient separations difficult. Separation scientists are addressing these challenges by modifying mobile phase compositions, using varying ion-pairing reagents, and exploring alternative separation modes like HILIC and ion-exchange chromatography. Due to these complexities, AMT has introduced the HALO® OLIGO column, which offers high-resolution, fast separations through its innovative Fused-Core® technology and high pH stability. Alongside explaining the new column, Peter looks to the future of these separations and what is next to come.
A Guide To Finding the Ideal Syringe and Needle
January 20th 2025Hamilton has produced a series of reference guides to assist science professionals in finding the best-suited products and configurations for their applications. The Syringe and Needle Reference Guide provides detailed information on Hamilton Company’s full portfolio of syringes and needles. Everything from cleaning and preventative maintenance to individual part numbers are available for review. It also includes selection charts to help you choose between syringe terminations like cemented needles and luer tips.
