Chromatography 13 Optimising Pump Performance with Early Gas Bubble Detection
Testa Analytical has released a study showcasing the effectiveness of their Solvent Line Monitor in preventing issues caused by undissolved gas bubbles in HPLC, flow chemistry, or liquid dosing systems.
Undissolved gas bubbles can significantly impact the performance of peristaltic pumps, particularly in HPLC systems. While vacuum degassers are commonly used to remove dissolved gas, they are ineffective when it comes to undissolved gas bubbles. These bubbles can bypass the degassing device, reach the peristaltic pump, and cause operational problems and errors in analytical results.
The study provides data demonstrating the influence of dissolved gas on peristaltic pump performance and highlights the adverse effects of undissolved gas bubbles. Testa Analytical’s Solvent Line Monitor offers a practical solution to address this issue.
This innovative device features optical and acoustic alarms, along with a digital output that can halt a chromatography or flow chemistry pump before an undissolved gas bubble disrupts its operation. The Solvent Line Monitor is user-friendly and programmable, allowing adjustments in sensitivity, operating mode, and bubble detection alarms. The setup process is straightforward, facilitated by an intuitive PC-based application included with each Solvent Line Monitor. Users can configure parameters such as minimum bubble size, frequency, and the number of bubbles, and specify actions to take upon detecting an alarm, whether it’s a simple beep or a complete pump stop.
Read the in-depth study in full:
ilmt.co/PL/x4RA More information online:
ilmt.co/PL/Op8B
Transforming Nitrite Screening in Pharma
Pharmaceutical manufacturers face the demanding and complex task of controlling nitrosamine levels within their product lines. One of the most effective ways of managing this is to control the levels of nitrites within the product. However, a quick and effective method for establishing the level of nitrite content present down to very low ppb levels has proved challenging with existing technology and methods.
The Automated Total Nitrosamine Analyser (ATNA) from Ellutia, can help pharmaceutical companies tackle this challenge. Whilst most commonly used for nitrosamine screening, The ATNA can also rapidly screen for total nitrite content down to low ppb levels. The System can handle a wide range of sample types with minimal sample preparation. Samples are placed into headspace vials along with a reagent mixture. The Robotic Autosampler then performs the chemical reaction, and the headspace is sampled and directly injected into the Ellutia TEA Detector. This means there is no separation of compounds, and a single result for total content is produced. Specifically developed SPE cartridges can be used to differentiate between signals from nitrosamine and nitrite compounds.
The ATNA allows users to rapidly screen samples for both nitrosamine and nitrite content, giving greater confidence and visibility of where potential issues may be. Allowing them to focus resources where it really matters.
More information online:
ilmt.co/PL/jXb8 61016pr@reply-direct.com ADVERTORIAL Determination of Optimum Method Parameters for the Analysis of Oligonucleotides via HILIC
Due to the highly polar nature of oligonucleotides, hydrophilic interaction liquid chromatography (HILIC) is ideally suited for their characterisation. In a new technical note, the separation of mixtures of short DNA (dT10, dT15 and dT20) and short RNA oligonucleotides (14, 17, 20 and 21mer) was used to examine important parameters for method optimisation in HILIC mode.
Influence of hardware Oligonucleotides can be irreversibly adsorbed onto the metallic surface of the column hardware, due to their electron-rich backbone. The use of a bioinert coated YMC-Accura Triart Diol-HILIC column shows better peak shapes and higher sensitivity due to virtually no adsorption compared to the corresponding stainless-steel column (see Figure 1).
Influence of sample solvent and mobile phase pH The influence of the sample solvent on peak shape especially for early eluting peaks is significant. As water is the strong eluent in HILIC mode, the ratio of organic solvent must be the same or higher than the initial gradient composition. The analysis of the DNA oligonucleotides diluted with a lower organic ratio (40%) shows that a higher injection peak as well as early eluting additional peaks occurs.
The mobile phase pH has a significant effect on retention and peak shape. Figure 2 shows that oligonucleotides are more strongly retained when the pH becomes lower. But with an acidic pH massive adsorption of the oligonucleotides occurs. Using the basic mobile phase, the retention is the lowest, but the resolution is visibly reduced, so that the neutral mobile phase pH shows the best results for this mixture.
Summary
These findings result in the following recommendations:
• Bioinert hardware provides optimum peak shapes and high recovery
• High organic ratio of the sample solvent is important
• Neutral to basic mobile phase pH is recommended
You will find further information about oligonucleotide analyses in YMC’s Oligonucleotide columns brochure.
More information online:
ilmt.co/PL/4Zle and
ilmt.co/PL/mVAl
61270pr@reply-direct.com
Figure 1: Analysis of DNA oligonucleotides using the bioinert coated YMC-Accura Triart Diol-HILIC (blue) and the corresponding stainless-steel column (grey).
Figure 2: Influence of mobile phase pH on the separation of an all PO RNA mixture using an acidic (red), a neutral (blue) and basic pH (green).
61325pr@reply-direct.com
WWW.LABMATE-ONLINE.COM
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52 |
Page 53 |
Page 54 |
Page 55 |
Page 56 |
Page 57 |
Page 58 |
Page 59 |
Page 60 |
Page 61 |
Page 62 |
Page 63 |
Page 64
