II. SERDOLIT® PAD Adsorber Resins

Whereas ion exchangers (mainly) bind charged molecules, neutral adsorbent resins can be used for the extraction and in some cases even for the separation of neutral, basic and acidic substances. This adsorption process often is performed with compounds which are dissolved in water or in a solution which does not contain too much of an organic solvent that might prohibit the interaction (van der Waals forces, hydrophobic, hydrophilic bridges) between adsorbent and adsorbate.
SERVA offers 2 types of adsorber resins: polar and unpolar ones. The unpolar types SERDOLIT®  PAD I, II and III are macroporous copolymerisates of polystyrene and DVB. They are supplied each in 2 particle sizes: 0.1 – 0.2 mm and 0.3 – 1.0 mm. They have similar pore sizes (approx. 25 nm) but differ in specific surface:

 PAD I  min. 250 m2/g
 PAD II  min. 400 m2/g
 PAD III  min. 800 m2/g

Generally speaking, the larger the surface, the higher is the capacity.

The polar resin SERDOLIT® PAD IV is a macroporous copolymerisate of acrylic ester and DVB. It is supplied with a particle size of 0.3 – 1.0 mm and has a pore size of approx. 20 nm and a specific surface of min. 250 m2/g.

Unpolar resins bind organics from water, polar resins even from organic solvents. Unwanted substances (impurities, salts) are eluted with water, the enriched compound(s) with water mixable organic solvents. Their eluotropic forces are known from chromatographic experience. Acidic molecules are best eluted with basic eluents, basic molecules under acidic conditions.
SERVA´s PAD resins are highly purified adsorbents which are prewetted (hydrophilized) and can be used straight away. These fine mesh resins may be used not only for solid phase extraction (SPE) but also in the well known reversed phase low and medium pressure chromatography up to 10 bars (140 psi) with the advantage to be hydrolytically stable within the entire pH range.
Table 9 lists compounds which can be extracted from water resp. waste water with SERDOLIT® PAD resins.

Table 9: Selection of compounds adsorbed with SERDOLIT® PAD resins

Aniline & substituted anilines
Benzene & substituted benzenes
Benzoic acid & its derivatives
Chlorinated hydrocarbons                     
Fatty acids
Humic acids and humic-like substances
Organophosphorous compounds
Organosulfur compounds
Phenol & derivatives
Polychlorinated biphenyls & other chlorinated compounds
Polynuclear aromatic compounds
Purine & pyrimidine bases and derivatives
Pyridine & substituted pyridines


Product of the Month December:
Xpress Blotting Kits

Autumn Campaign 2017 -
Great Saving!

Hoefer Promotion -
valid until 31.12.2017

BioDrop Promotion -
valid until 31.12.2017

Close window
Product of the Month December:
Xpress Blotting Kits

Only 15 Minutes for Semi-Dry Western Blotting.

This way to the Special Offer

Close window
Autumn Campaign 2017 -
Great Saving!
  • PRiME™-Packages for Minigel SDS PAGE
  • Protein Electrophoresis
  • Nucleic Acid Electrophoresis
  • Western Blotting
  • Laboratory Equipment
  • Trypsin MS Approved
  • DNA Decon

This way to the campaign

Close window
Hoefer Promotion -
valid until 31.12.2017

Save 25 % :

  • Mini Vertical Electrophoresis Units
  • Standard Vertical Electrophoresis Units
  • Tank Blotter

This way to the Promotion

Close window
BioDrop Promotion -
valid until 31.12.2017

BioDrop UV/VIS Spectrophotometer at a Glance:

  • BioDrop TOUCH
  • BioDrop µLITE
  • BioDrop DUO

This way to the promotion!


SERVA InfoMail - Get the latest information

Close window

When subscribing to »SERVA InfoMail« you will receive information about the latest product release, special promotions, new jobs at SERVA and more. This service is, of course, free of charge.
You may remove your name any time from the list of recipients.

Quick Order

Close window

Using the Quick Order field, you can add a product to your shopping cart with just one click. All you have to do: enter the Cat.No. as shown in our catalog in the format xxxxx.yy and click the Go!-Button.