What causes peak splitting HPLC?

The most common causes for peak splitting are i) too strong injection solvent compared to mobile phase composition at elution, ii) column channelling, iii) partially clogged part of the system (column, filter etc.). A too high acquisition rate may also cause jagged peaks.

What is peak splitting?

Peak splitting is when a Gaussian peak gets a shoulder or a twin. They have the same base, are unexpected and can be caused by a number of factors. The splitting can affect all peaks or just one, and different effects can be attributed to different causes.

How do you separate two peaks in HPLC?

My hunch is that a change in the proportion of acetonitrile in the mobile phase may help to separate the peaks. You could also try reducing the flow rate of the mobile phase, and reducing the column temperature. Try a gradient separation first. It will most likely allow you to separate the 2 co-eluting compounds!

How do you separate closely eluting peaks in HPLC?

Some compounds of high molecular weight may not be separable on small pore size packings, but will be easily resolved on a column packed with larger-pore packing. Generally, the easiest way to resolve closely or co-eluting peaks is to change the bonded phase on the column packing.

Why is XRD peak splitting?

Peak splitting is taking place due to the phase transformation. For example BaTiO3 ceramics has splitting peak at around 2theta angle of 45 which is specifying the tetragonal phase.

How do you reduce peak splitting in HPLC?

The problem of the peak splitting can be solved by reverse flushing most of the times as it removes the contaminant from the column and may also dissolve the absorbed contaminants if the impurities in the column is soluble in the Mobile Phase. 2) Wash the column with 90% Organic phase such as Acetonitrile or Methanol.

How do you stop peak splitting?

What is Ghost peak in HPLC?

Ghost peaks are contaminant peaks that appear even when no sample is injected. There are many causes for ghost peaks and this note will describe how to troubleshoot these contaminant peaks, when you see them. The primary cause of a ghost peak is a dirty pre-column or column.

How do I fix peak tailing in HPLC?

There are a few methods that can be used to avoid peak tailing:

1. Operate at a lower pH.
2. Use a highly deactivated column.
3. Consider the possibility of mass overload.
4. Consider the possibility of column bed deformation.
5. Work at high pH when analyzing basic compounds.
6. Use a sample clean-up procedure.

How do you increase peak shape in HPLC?

In both cases the solution is quite simple: Dilute the sample or reduce the injection volume. The pH of the mobile phase can also have a strong influence on the peak width. Depending on the chemical property of a sample, it can be ionized in different ways, i.e., completely protonated, deprotonated or neutral.

Why some peaks have higher intensity in XRD pattern?

Intensity is proportional to the number of scatterers per unit area of a given atomic plane and therefore the peak intensities in an XRD experiment will vary. Secondly, it might due to the measured crystals have texture in some directions, causing the higher intensity peaks.

What is Cu K alpha radiation?

Copper K-α is an x-ray energy frequently used on labscale x-ray instruments. The energy is 8.04 keV, which corresponds to an x-ray wavelength of 1.5406 Å. K-alpha radiation has higher intensity rather than K-beta, so it is commonly used in diffractometers.

What does the splitting of a NMR signal mean?

NMR signals may have different number of peaks (the number of lines). This is called the splitting of the signal or the multiplicity. Signal splitting is arguably the most unique important feature that makes NMR spectroscopy a comprehensive tool in structure determination.

What causes peak splitting on a HPLC column?

A poorly packed column, void at column inlet, a dirty frit or poor mechanical connection (i.e. improperly swaged fitting). These types of structural or mechanical defects can each result in peak “splitting” (all of these are less common today than in the past using modern HPLC columns).

What does the n + 1 rule mean in NMR spectroscopy?

Splitting and Multiplicity (N+1 rule) in NMR Spectroscopy NMR signals may have different number of peaks (the number of lines). This is called the splitting of the signal or the multiplicity. Signal splitting is arguably the most unique important feature that makes NMR spectroscopy a comprehensive tool in structure determination.

What can be done about peak splitting in chromatography?

Using in-line filters and column guards can reduce the incidence of blockages in a chromatography system, so preventing peak problems. The problem of blocked frits is highlighted in: ACE Ultra Low Dispersion, High Quality UHPLC and HPLC Pre-column Filters.