Warning! Unfortunately your browser has disabled scripting. Please enable it in order to display this page.
 

High Quality HPLC Sample Filtering Solutions | Greyhound Chromatography

High Quality Filtering Solutions

                                 Q-Fil Filters ImageQ-Fil Syringe Filters Catalogue Cover Image      Q-Fil Membrane Filters Catalogue Image

 

The main source of particle contamination in HPLC columns originate in the sample to be analysed. Therefore, the final preparation step prior to sample injection into the HPLC instrument is to remove any small particulates from the sample by filtration. Removal of the solid materials is very important as they can interfere with the compound of interest and easily clog up the column being used. This will inevitably have a detrimental effect on the performance of the column, i.e. back pressure, peak size, retention time, peak shape. Severe contamination can lead to the column being irreversibly blocked and therefore having to be replaced. Other costs can include instrument downtime, and the loss of valuable samples.

Sample Types

Samples differ in a variety of ways, they may be heavily loaded with fine or coarse particulates, dissolved in aqueous or organic solvents with varying viscosities. To facilitate the most appropriate sample preparation result, filters should be optimised to match the particular requirements of each kind of sample being injected.

Standard Samples

A matrix of 5-10mL is the most common sample volume, with low viscosity, low particle contamination and dissolved in either an organic or an aqueous solvent. Greyhound Q-Fil Regenerated Cellulose Syringe Filters are an excellent choice for such samples. Their inert housing manufactured from high density medical grade virgin polypropylene, complete with the integrated Regenerated Cellulose (RC) membrane has a high chemical resistance against the most common HPLC solvents and is very suitable for aqueous samples. Every batch is HPLC-tested for low extractables. Whilst 0.45µm is the most commonly used membrane porosity, the 0.22µm membrane provides improved purity when using capillary columns or HPLC packings with a particle size of 3µm or less

Demanding Samples

More difficult samples which contain high loads of particulates, high viscosity or unusually high volumes place additional challenges on the user when preparing samples for HPLC analysis. The particles have a tendency to block the filter, high viscosities will decrease the flow rate and high volumes increase the time required to complete the filtration process. These challenges often result in the user applying a greater degree of manual pressure to the process and potentially exceeding the maximum pressure limit of the filter with a subsequent risk of bursting the housing. As a result, the sample will be lost and a potential safety risk can arise if corrosive solvents or harmful chemicals are being filtered. To assist in overcoming these challenges, the use of Q-Fil Syringe Filters with a built in Glass Microfiber pre-filter are recommended. The pre-filter removes the larger particulates from the sample leaving only the smaller particulates to be filtered by the membrane. These filters increase the flow rate through the unit resulting in a higher volume of sample to be filtered and less pressure being required by the user.

Small Volume Samples

Smaller volume samples are often valuable and require special attention. Any loss of the analyte due to adsorption by the filter membrane or housing or a large dead volume can have a detrimental effect on the analysis. Smaller filters of 13mm and 4mm diameter decrease the dead volume to less than 25uL and 8uL respectively making them ideal for smaller volume samples.

Summary

Sample filtration is an important factor in ensuring that HPLC analysis is achieved in an efficient and cost-effective way. The extensive range of Q-Fil Syringe Filters have been developed to meet the demands of the analyst and the different sample matrices being used and without losing any of the important sample.

Quality is an Important Factor

Greyhound ensures that every batch of filters is manufactured and tested in accordance with strict ISO 9001:2000 quality procedures.

Greyhound ensures that each batch is checked prior to release for:

- External Dimensions - Bubble Point - Water Flow Rate - UV Extractables - Burst Pressure and compliance - Filter Integrity.

Choosing a filter on price against quality is not cost effective in the long run.  Although higher spec filters may seem expensive it is false economy to choose cheaper filters as their fail rate is much higher, causing delays in the laboratory.

Q-Fil Syringe Filters

How to choose the right syringe filter for your application

  •          Choose the size of filter based on the volume of sample to be filtered
  •          Choose the filters porosity based on the size of the potential particulates in the sample. It is important to be aware that the finer the porosity of the membrane the greater the pressure will be required to pass the sample through the filter. A sample containing large quantities of particulates is best filtered using a filter with a built-in glass microfiber pre-filter
  •          Choose the type of membrane based on the solvent being filtered

 

30mm Diameter

Designed for the largest sample volumes or solvent filtration

Filtration area 5.39cm2

Maximum filtration volume <200ml

Maximum operating pressure 87psi (6.0 bar) at 20°C Sample volume <200ml

Holdup volume <200µl

30mm Syringe Filter Image

 

 

25mm Diameter

Designed for larger sample volumes or solvent filtration Filtration area 4.08cm2

Maximum filtration volume >100ml

Maximum operating pressure 87psi (6.0 bar) at 20°C Sample volume <100ml

Holdup volume <100µl

Purple Syringe Filter Image

 

13mm Diameter

Suitable for most applications

Filtration area 1.09cm2

Maximum filtration volume >10ml

Maximum operating pressure 87psi (6.0 bar) at 20°C Sample volume <10ml

Holdup volume <25µl

Green Syringe Filter Image

 

4mm Diameter

Suitable for smaller volume applications

Filtration area 0.1cm2

Maximum filtration volume <2ml

Maximum operating pressure 75psi (5.0 bar) at 20°C Sample volume <2ml

Holdup volume <8ul

 Yellow Syringe Filters Image

Pore Sizes

Q-Fil Syringe Filters are available in 0.22µm and 0.45µm pore sizes, (other pore sizes are available on request). The 0.22µm filters remove the smallest particulates whilst the 0.45µm filters are designed to remove particulates which would be detrimental to most analytical columns.

Pre-filters have a glass microfiber membrane which is chemically inert and resists most solvents. Q-Fil glass microfiber pre-filters are recommended for removing large particulates from the sample and are ideal for dissolution tests.

 Syringe Filters with Glass Microfiber Pre-Filter

 

  • These filters have the same high-quality filter membranes and polypropylene housings as our other Q-Fil Syringe Filters, but include a Glass Microfiber (GMF) membrane used as a pre-filter    

 

  • The glass microfiber pre-filter is mounted before the microporous filter membrane, eliminating the need for a pre-filtration step, minimising sample loss and prolonging the life of the filter membrane

 

 

 

     
  • Flow rates are increased and the filtrate volume is significantly greater when compared to filters without pre-filters

 

  • Regenerated Cellulose membrane filters with the GMF membrane incorporated as a pre-filter, are particularly useful for tissue culture media filtration, as well as for general biological sample filtration

 

 
  • These filters are ideal for general laboratory filtration of samples which contain excessive amounts of particulates

 

  • The glass microfiber pre-filter removes the large particulates and prevents premature clogging of the filter membrane

   

Greyhound Q-Fil Membrane Filters

 Q-Fil Membrane Filters set the new Quality standard for today’s analytical laboratories. Manufactured from the highest quality materials, Q-Fil Membrane Filters provide excellent chemical compatibility with acids, alcohols, bases, ethers, glycols, ketones and oils.

 

As a trusted name in the supply of chromatography consumables and certified reference standards, Greyhound also offers a comprehensive selection of top quality own brand products including Capillary columns HPLC columns, Syringe Filters, Consumables etc. This catalogue contains details of our range of Q-Fil Membrane Filters.  Other product catalogues are available on request.

 

  These quality products are backed by the guaranteed reliability and technical support which has become synonymous with the name Greyhound.   

 

 



 

                       Q-Fil Filters Image                         Q-Fil Membrane Filters Catalogue Cover Image

 

 

 

 Membrane Filter Comparison Chart

 

 Q-Fil Membrane Filters Comparison Chart Image

 

Q-Fil Membrane Filters Comparison Chart [2] Image

 

 

 

NYLON

Features:

  •  Hydrophilic membrane
  •  Excellent for HPLC samples and general filtration
  •  Compatible with organic and aqueous liquids
  •  Good solvent resistance and high protein retention
  •  Strong mechanical stability

Not suitable for use with strong acids or bases, halogenated hydrocarbons or protein

Special discounts are available for call-off and bulk orders, please enquire.

 Multiple Pore Sizes and Diameters Available. 

Nylon Filter Membrane Image

 

 

 

PTFE Hydrophobic

Features:

  •  Hydrophobic membrane resistant to strong acids, aggressive solvents, alcohols, bases and aromatics
  •  Ideal for the filtration and degassing of chromatography solvents and for extremely basic mobile phase solutions
  •  Very low extractables
  •  Mechanically strong
  •  Excellent thermal stability
  • Multiple Pore Sizes and Diameters Available. 

 

PTFE Hydrophobic Membrane filter Image

 

 

 

PTFE HydrophilicFeatures:

  •  Hydrophilic membrane resistant to strong acids, aggressive solvents, alcohols, bases and aromatics
  •  Ideal for the filtration and degassing of chromatography solvents and for extremely basic mobile phase solutions
  •  Very low extractables
  •  Mechanically strong
  •  Excellent thermal stability
  • Multiple Pore Sizes and Diameters Available. 
Membrane filters Image

 

 

 

CELLULOSE NITRATE

Features:

  •  Naturally hydrophilic
  •  High physical strength
  •  Ideal for clarification and filtration of aqueous samples
  •  For immunoblotting, the high protein retention of Nitrocellulose is ideal to bind DNA
  • Multiple Pore Sizes and Diameters available

 

Membrane filters Image

 

 

 

CELLULOSE ACETATE

Features:

  •  Hydrophilic membrane
  •  Ideal for aqueous based samples, tissue

      culture media filtration and sensitive

      biological samples

  •  Very low protein binding capacity,

lower than PVDF and PES membranes

  •  High physical strength
  •  Strength and dimension stability
  •  Lower chemical resistance than Regenerated Cellulose

 Multiple Pore Sizes and Diameters available. 

 

 

 

 

PVDF (Hydrophobic)

Features:

  •  Polyvinylidene difluoride membrane
  •  Hydrophobic
  •  Wide chemical compatibility
  •  Excellent mechanical properties
  •  Resistant to solvents, exhibits low levels of extractables
  •  Low protein binding, can be used with proteins and peptides
  •  Suitable for filtration of aqueous and organic solvents
  • Multiple Diameters and Pore Sizes Available

 

 

 

 

MIXED CELLULOSE ESTERS - Gridded

Features:

Gridded MCE membranes are unsupported natural hydrophilic filters which have clearly defined grid lines.  The special ink used is non-toxic and completely free from bacterial growth inhibitors.  Composed of cellulose acetate and cellulose nitrate, they are one of the most widely used membranes in analytic and research applications.

The white gridded disks are specially designed for the recovery and retention of E.Coli bacteria in water/waste water analysis as well as other microbiological tests. 

The black gridded disks assist with manual counting procedures and provide enhanced contrast between residue or cell colours and the filter without having to counter stain the membrane.

 

 

Mixed Cellulose Esters Membrane Filters Image

 

 

 

 

Features

  •  Hydrophobic
  •  Gridded membrane is perfect for microbiology analysis
  •  0.22µm, 0.45µm and 0.8µm pore sizes available
  •  Sterilised by gamma irradiation
  •  Individually packaged with easy to open separator paper

 

Applications

  •  Clarification of aqueous solvents, removal and analysis of microbiological contaminants
  •  Sterilizing filtration, air monitoring, particle monitoring, particle removal, bioassay
  •  Dairy microbiology, retention of yeast, moulds and algae
  •  QC analysis of fluid holding, particle collection and analysis

 

 

POLYETHERSULFONE

Features:

  •  Inherently hydrophilic membrane
  •  Low protein binding
  •  Provides high flow rates and good throughput volume
  •  Best choice for tissue culture work
  •  Very low extractables
  •  Mechanically strong membrane, suitable for use with strong bases, alcohols and resistive proteins
  • Multiple Pore Sizes and Dimensions available.

 

 

POLYPROPYLENE

Features:

  •  Hydrophobic, high resistance to solvents
  •  High density with high capacity
  •  Wide range of chemical compatibility to organic solvents
  •  Ideal for biological sample filtration
  •  Low protein binding
  •  Ideal for chromatography protein analysis and biological sample filtration
  •  Suitable for acids and bases and general HPLC analysis
  • Multiple Pore Sizes and Dimensions available. 

 

 

GLASS FIBER

Features:

  •  Binder Free
  •  Commonly used as pre-filters for membranes to remove large particulates and prevent the membrane from silting   up
  •  Extends the loading capacity of filter membranes
  •  High flow rate and high permeability to air
  •  Reduce filtration costs and premature clogging of membranes when filtering difficult or highly contaminated solutions
  •  Excellent wet strength for easy handling and filter integrity
  • Multiple Pore Sizes and Dimensions available. 

 

Glass Fibre Membrane Filters Image

 

All Greyhound Vacuum Filtration Devices are made of stainless steel which is suitable for filtration, especially in the microbiological field.  

  •  Each station uses a separate control valve for independent operation, is easy to use and to disinfect.
  •  The multiple unit systems can filtrate three or six samples at the same time at a low flow rate, with high sensitivity.
  •  Sturdy won’t tip when fully loaded due to the units having a low centre of gravity.
  •  Anodized aluminum handles on both ends are designed for positioning on a benchtop.

 

Vacuum Filtration Systems Image

 

Cat. No.

Description

41-100600

Stainless steel manifold
One 300mL stainless steel filtration unit
One glass collection bottle
One  length of hosepipe

41-100601

Stainless steel manifold
One 300mL glass filtration unit
One glass collection bottle,
One length of hosepipe

41-100602

Stainless steel manifold
Three 300mL stainless steel filtration units
One glass collection bottle,
One length of hosepipe

41-100603

Stainless steel manifold
Three 300mL glass filtration units
One glass collection bottle,
One length of hosepipe

41-100604

Stainless steel manifold
Six 300mL stainless steel filtration units
One glass collection bottle,
One length of hosepipe

41-100605

Stainless steel manifold
Six 300mL glass filtration units
One glass collection bottle,
One length of hosepipe

41-100610

Stainless Steel Manifold, single unit

41-100611

Stainless Steel Manifold, three unit

41-100612

Stainless Steel Manifold, six unit

41-100613

Glass Funnel, 300mL

41-100614

Stainless Steel Funnel, 300mL

 

Greyhound Solvent Filtration Apparatus are used for the filtration of HPLC mobile phases, to remove particulate and microbiological contaminants.  Manufactured of durable borosilicate glass for use with aqueous, organic or corrosive liquids.  

Can be sterilised in an autoclave at 121°C.

The base design has an integral vacuum connection located above the filtrate drip to prevent contamination of the vacuum line with droplets.

Unit consists of a funnel, coarse porosity fritted glass filter support base with integral vacuum connection and a flask with inner joint.  An aluminium clamp connects the funnel and support base.

 

 

 

 

 

                               Filtration Flask Image  Filtration Flask ImageFiltration Flask Image  Filtration Flask Accessory   Filtration Flask Accessory Image    

 

Cat. No.

Description

41-100620

Glass Solvent Filtration Apparatus - 300mL for 47mm dia. filters
Graduated glass funnel, fritted glass base with side arm, joint flask, anodized aluminium clamp, vacuum hose

41-100621

Glass Solvent Filtration Apparatus - 500mL for 47mm dia. filters
Graduated glass funnel, fritted glass base with side arm, joint flask, anodized aluminium clamp, vacuum hose

41-100622

Glass Funnel - 300mL

41-100623

Glass Funnel - 500mL

41-100624

Glass Solvent Collection Flask - 1000mL

41-100625

Glass Solvent Collection Flask - 2000mL

41-100626

Glass Filter Head Kit (includes 300mL Glass Funnel, Fritted Glass Base, Clamp, Silicone stopper)

41-100627

Glass Filter Head Kit (includes 500mL Glass Funnel, Fritted Glass Base, Clamp, Silicone stopper)

41-100628

Aluminium Clamp