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Both C8 and C18 columns are considered as examples of reversed phase liquid chromatography (RP). The stationary phase here is seen as a thin film of non-polar liquid phase that has been designed to be chemically anchored to an inert material (Silica gel particles). The non-polar layer is chemically linked to the silica particles surface by reaction with the polar silanol groups on the stationary phase surface and so rendering them (less polar or non-polar), The difference between the two columns will be in the length of the carbon-chain attached to the silica surface. Acoordingly C8 hplc columns have packing material composed of silica particles attached to C8 carbon units while C18 will, of course, have packing materials coated with C18 hydrophobic units. Categorically both are reversed phase but C18 columns will definitely be more "hydrophobic" rather than the C8 columns.
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What are all the parameters that have impact on the polarity of C8 and C18 columns?
The key parameters that impact the polarity of C8 and C18 columns are the length of the alkyl chain attached to the silica surface, the mobile phase composition, the pH of the mobile phase, and the column temperature. These factors influence the retention and selectivity of compounds on the stationary phase.
What is C18 phase in hplc column?
Both C8 and C18 columns are considered as examples of reversed phase liquid chromatography (RP). The stationary phase here is seen as a thin film of non-polar liquid phase that has been designed to be chemically anchored to an inert material (Silica gel particles). The non-polar layer is chemically linked to the silica particles surface by reaction with the polar silanol groups on the stationary phase surface and so rendering them (less polar or non-polar), The difference between the two columns will be in the length of the carbon-chain attached to the silica surface. Acoordingly C8 hplc columns have packing material composed of silica particles attached to C8 carbon units while C18 will, of course, have packing materials coated with C18 hydrophobic units. Categorically both are reversed phase but C18 columns will definitely be more "hydrophobic rather than the C8 columns.
How do you select hplc column in method development?
firs you mist know the polarity for sample, wen the sample polar you can use "RP" column like C18 or C8 ( C18 first in pharmaceutical) . wen sample non polar use "NP" column like silica or CN Column. after that you can change the column in same packing to solve tailing, retention time, Resolution..... or any problem by change column length, particle size or carbon loud
Can C18 column for HPLC be used with UV and visible spectra detector and Acetonitril as mobile phase?
Of course.... there isn´t problem....
How many spinal nerves exit the vertebral column?
There are 31 pairs of spinal nerves that exit the vertebral column: 8 cervical (C1-C8), 12 thoracic (T1-T12), 5 lumbar (L1-L5), 5 sacral (S1-S5), and 1 coccygeal (Co).
What are all the parameters that have impact on the polarity of C8 and C18 columns?
The key parameters that impact the polarity of C8 and C18 columns are the length of the alkyl chain attached to the silica surface, the mobile phase composition, the pH of the mobile phase, and the column temperature. These factors influence the retention and selectivity of compounds on the stationary phase.
What is C8 and C18?
C8 and C18 refer to carbon chain lengths in fatty acids. C8 means the fatty acid has 8 carbon atoms in its chain, while C18 means the fatty acid has 18 carbon atoms in its chain. The number of carbon atoms in a fatty acid chain can affect its properties and functions in the body.
What is C18 phase in hplc column?
Both C8 and C18 columns are considered as examples of reversed phase liquid chromatography (RP). The stationary phase here is seen as a thin film of non-polar liquid phase that has been designed to be chemically anchored to an inert material (Silica gel particles). The non-polar layer is chemically linked to the silica particles surface by reaction with the polar silanol groups on the stationary phase surface and so rendering them (less polar or non-polar), The difference between the two columns will be in the length of the carbon-chain attached to the silica surface. Acoordingly C8 hplc columns have packing material composed of silica particles attached to C8 carbon units while C18 will, of course, have packing materials coated with C18 hydrophobic units. Categorically both are reversed phase but C18 columns will definitely be more "hydrophobic rather than the C8 columns.
How do you select hplc column in method development?
firs you mist know the polarity for sample, wen the sample polar you can use "RP" column like C18 or C8 ( C18 first in pharmaceutical) . wen sample non polar use "NP" column like silica or CN Column. after that you can change the column in same packing to solve tailing, retention time, Resolution..... or any problem by change column length, particle size or carbon loud
Can you use a C18 column for HPLC with fluorescence detector and methanol as the mobile phase?
Yes, you can use a C18 column and methanol as a mobile phase with fluorescence detector. Fluorescence detector is generally used as it can detect the presence of compounds at a very low concentration.
Can you use PBS as mobile phase in C18 column?
Yes, PBS (phosphate-buffered saline) can be used as a mobile phase in a C18 column, particularly for reverse phase chromatography. However, it is important to consider the pH and ionic strength of the PBS, as these factors can influence retention time and separation efficiency. Additionally, the presence of salts in PBS may affect the column’s performance and longevity, so it is advisable to validate the method for specific applications.
How do i add cell c3 to c8 on an excel formular bar?
You would use the formula: =C3+C8 unless you mean to add everything from C3 to C8. IN that case you would use the formula =SUM(C3:C8)
Explain the rationale for using a reversed phase C18 column for the determination of caffeine?
A reversed phase C18 column is commonly used for the determination of caffeine due to its hydrophobic properties, which can efficiently separate caffeine from other compounds in the sample based on their differing affinities for the stationary phase. Caffeine, being relatively nonpolar, interacts strongly with the C18 column, allowing for good retention and separation. Additionally, C18 columns are compatible with common mobile phases used in high-performance liquid chromatography (HPLC), making them a popular choice for caffeine analysis.
Can C18 column for HPLC be used with UV and visible spectra detector and Acetonitril as mobile phase?
Of course.... there isn´t problem....
What is c8?
Tecno phone camon c8
Spinal nerve C8 exit between two vertebrae C7 - C8?
Yes, the spinal nerve C8 exits between the C7 and C8 vertebrae. In the cervical region, there are eight cervical spinal nerves (C1 to C8), but only seven cervical vertebrae. Therefore, the C8 nerve root exits below the C7 vertebra and above the C8 vertebra, which is why it is uniquely positioned.
Why is there a C8 vertebrae?
The C8 vertebra is not a true vertebra but rather an anatomical and numerical anomaly in the human cervical spine. It is an occasional variation seen in some individuals where there is an extra rib arising from the seventh cervical vertebra. This condition is known as a cervical rib.
