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Cell, Protein, Membrane Purification & Isolation

 

Protein Purification & Isolation

Easily extract, purify, clean up, and concentrate your proteins of interest with our kits, reagents, and devices. These products are optimized for a wide range of tissue and cell types and compatible with a broad range of protein purification resins and formats, which offer more choices and better protein recovery. Desalt, buffer exchange, remove contaminants and concentrate proteins with our secure and efficient devices and resins.

What do we offer?

  • Protein Purification & Isolation

– Cell Lysis and Fractionation

  • Detergents for Protein Solubilization
  • Organelle Isolation
  • Organelle Isolation Using Magnetic Beads

– Subcellular Fractionation

– Protease and Phosphatase Inhibition

  • Protease Inhibitors
  • Phosphatase Inhibitors
  • Combined Protease and Phosphatase Inhibitors

Cell Lysis (Total Protein Extraction)

B-PER™ Bacterial Cell Lysis Reagents

 

 

 

Cell Lysis and Fractionation

Our tissue lysis, cell lysis, and cell fractionation products are optimized for sample type. The lysates or fractions collected are compatible with a wide range of downstream applications.

Features include:

  • High protein yields from cells or tissues
  • Gentle formulations that preserve protein activity for downstream assays
  • Directly compatible with protein assays, immunoprecipitation, immunoassays, western blotting, EMSA, and enzyme assays
  • Validated using multiple tissue types and cell lines
  • Eliminates the need for mechanical cell disruption

Sample type

Fraction of interest

Organelle type

Mammalian cells & tissues

Primary cells & tissue

Neuronal

Bacteria

Yeast

Insect

Plant

Multiple subcellular fractions

Cell surface

Membrane

Nuclear & Cytoplasmic

Chromatin-bound

Cytoskeletal

Mitochondria

Lysosomes

Synaptosomes

 

 




 

Membrane disruption, protein binding and solubilization

Generally, moderate concentrations of mild (i.e., nonionic) detergents compromise the integrity of cell membranes, thereby facilitating lysis of cells and extraction of soluble protein, often in native form. Using certain buffer conditions, various detergents effectively penetrate between the membrane bilayers at concentrations sufficient to form mixed micelles with isolated phospholipids and membrane proteins.

Denaturing detergents such as SDS bind to both membrane (hydrophobic) and non-membrane (water-soluble, hydrophilic) proteins at concentrations below the CMC (i.e., as monomers). The reaction is equilibrium driven until saturated. Therefore, the free concentration of monomers determines the detergent concentration. SDS binding is cooperative (i.e., the binding of one molecule of SDS increases the probability that another molecule of SDS will bind to that protein) and alters most proteins into rigid rods whose length is proportional to molecular weight.


Non-denaturing detergents such as Triton X-100 have rigid and bulky nonpolar heads that do not penetrate into water-soluble proteins; consequently, they generally do not disrupt native interactions and structures of water-soluble proteins and do not have cooperative binding properties. The main effect of non-denaturing detergents is to associate with hydrophobic parts of membrane proteins, thereby conferring miscibility to them.

At concentrations below the CMC, detergent monomers bind to water-soluble proteins. Above the CMC, binding of detergent to proteins competes with the self-association of detergent molecules into micelles. Consequently, there is effectively no increase in protein-bound detergent monomers with increasing detergent concentration beyond the CMC.

Detergent monomers solubilize membrane proteins by partitioning into the membrane bilayer. With increasing amounts of detergents, membranes undergo various stages of solubilization. The initial stage is lysis or rupture of the membrane. At detergent:membrane lipid molar ratios of 0.1:1 through 1:1, the lipid bilayer usually remains intact but selective extraction of some membrane proteins occurs. Increasing the ratio to 2:1, solubilization of the membrane occurs, resulting in mixed micelles. These include phospholipid–detergent micelles, detergent–protein micelles, and lipid–detergent–protein micelles. At a ratio of 10:1, all native membrane lipid:protein interactions are effectively exchanged for detergent:protein interactions.



Detergents for Protein Solubilization

Detergents are amphipathic molecules containing both a nonpolar "tail" having aliphatic or aromatic character, and a polar "head." The ionic character of the polar head group forms the basis for broad classification of detergents; they may be ionic (charged, either anionic or cationic), nonionic (uncharged) or zwitterionic (having both positively and negatively charged groups, but with a net charge of zero).

Detergents are frequently used in cell lysis reagent formulation, for protein solubilization procedures, in wash buffers for ELISA, and for other protein research methods. Our detergents are available in three types of packaging.

Thermo Scientific™ Pierce™ Surfact-Amps™ detergents are highly purified, precisely diluted (10%) formulations that are ideal for applications or assays that are sensitive to contaminants that are present in unpurified detergents.  We test every batch to insure that our detergents contain <1.0 µeq/mL peroxides and carbonyls and package them under nitrogen, to prevent oxidization during storage.

  • Superior quality—lower measurable contaminant levels than other leading vendors
  • Accurate—precise 10% detergent solution in ultrapure water
  • Easy-to-use—solution is simple to dispense and dilute for use
  • Exceptionally pure—less than 1.0 µeq/mL peroxides and carbonyls
 


Properties of common detergents

Detergent

Description

Aggregation Number

Micelle MW

MW

CMC (mM)

CMC % w/v

Cloud Point (°C)

Dialyzable

Triton X-100

Nonionic

140

90,000

647

0.24

0.0155

64

No

Triton X-114

Nonionic

537

0.21

0.0113

23

No

NP-40

Nonionic

149

90,000

617

0.29

0.0179

80

No

Brij®-35

Nonionic

40

49,000

1225

0.09

0.1103

>100

No

Brij-58

Nonionic

70

82,000

1120

0.077

0.0086

>100

No

Tween®-20

Nonionic

1228

0.06

0.0074

95

No

Tween-80

Nonionic

60

76,000

1310

0.012

0.0016

No

Octyl Glucoside

Nonionic

27

8,000

292

23-25

0.6716-0.7300

>100

Yes

Octylthio Glucoside

Nonionic

308

9

0.2772

>100

Yes

SDS

Anionic

62

18,000

288

6-8

0.1728-2304

>100

Yes

CHAPS

Zwitterionic

10

6,149

615

8-10

0.4920-0.6150

>100

Yes

CHAPSO

Zwitterionic

11

6,940

631

8-10

0.5048

90

Yes

 



Surfact-Amps detergents

Catalog  #

Name

Size

Price (EUR)

85111

Triton™ X-100 Surfact-Amps™ Detergent Solution

50 mL

205

28313

1 L

2291

28314

6 x 10 mL

226

85112

250 mL

702

28332

Triton™ X-114 Surfact-Amps™ Detergent Solution

6 x 10 mL

444

85113

Tween20 Surfact-Amps™ Detergent Solution

50 mL

210

28320

6 x 10 mL

244

28321

1 L

2301

85114

250 mL

831

85115

500 mL

831

28329

Tween™ 80 Surfact-Amps™ Detergent Solution

50 mL

210

28230

500 mL

2400

28328

6 x 10 mL

241

85124

NP-40 Surfact-Amps™ Detergent Solution

50 mL

218

28324

6 x 10 mL

241

85125

500 mL

1307

85117

Brij™-35 Surfact-Amps™ Detergent Solution

50 mL

214

28316

6 x 10 mL

244

85118

500 mL

1307



Other detergents available in liquid and solid formats

Catalog  #

Name

Size

Price (EUR)

89902

n-Dodecyl-beta-Maltoside Detergent

1 g

220

5 g

716

89903

28300

CHAPS Detergent (3-((3-cholamidopropyl) dimethylammonio)-1-propanesulfonate)

5 g

241

28299

100 g

1714

28364

Sodium Dodecyl Sulfate (SDS), Lauryl

100 g

138

1 kg

408

28365

28312

Sodium Dodecyl Sulfate (SDS), C12

500 g

358