Product Code: 6129

DeltaPi is a tensiometer especially developed for studying interactions in biological systems.

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DeltaPi and DeltaPi-4

Kibron's unique single and 4-channel Langmuir-tensiometers penetration300x192.jpg

Kibron DeltaPi and DeltaPi-4 are novel types of instruments: Langmuir-tensiometers, which allow you to measure the binding of drugs, peptides, and proteins to lipid membranes - easily and with unparalled sensitivity. We innovate instruments for your innovative science.

Biomembranes and lipids are entering the forefront of biosciences, biotechnology and drug discovery. In these studies lipid monolayers have paved way to breakthroughs in the elucidation of the molecular mechanisms of action of lung surfactants, antimicrobial peptides, lipid signaling, blood coagulation, and cell adhesion, just to name a few examples. Drug-lipid and protein-lipid interactions have emerged as a new, very exciting area in drug discovery, deciphering the roles of e.g. phosphatidylinositols (PIPs) in controlling cytoskeleton-membrane interactions. Along similar lines, recent findings have demonstrated the key role of lipid membranes in promoting the formation of toxic oligomers by Alzheimer Abeta peptide, prions, alpha-synuclein, and IAPP (amylin).

DeltaPi series of Langmuir-tensiometers allow you to detect the penetration of drugs, peptides/proteins and nucleic acids into monolayers of specified lipid composition and at precisely controlled lateral packing density. The volume of the magnetically stirred subphase is minimally 150 microliters, which keeps your material consumption very low. One milligram of an antimicrobial peptide, for instance, is sufficient for a comprehensive characterization of its lipid-binding properties. Further, the choice of materials eliminates unwanted non-specific surface effects.

DeltaPi is a single-channel model, while DeltaPi-4 is equipped with four parallel microbalances, increasing significantly the throughput of experiments. When you are in a hurry and need to generate data fast, DeltaPi-4 is your choice.

Both instruments measure surface tension with Kibron's thin wire probes (DyneProbes) from small subphase volumes. They are compact and have an open and robust construction, easy to clean and maintain, operated with our intuitive software, DeltaGraph.

Reproducibility and reliability go hand-in-hand in science and in all Kibron products. DeltaPi and Deltapi-4 outperform all competing products, no matter how you compare them. This is the reason why you find Kibron equipment in leading research laboratories worldwide.

Product code Description
#6034 Sensor head
#1500 Set of DyneProbes, 4pcs
#6102 Aluminium BasePlate
#3530 Sample cup, set of 50 pcs
#6309 Power supply (110V-240V AC/12V DC)
#1502 Mains adapter US/JPN/EU/UK
#6305 Ground cable
#6238 Connecting cable
#6240 Computer cable
#6018 Electronics Unit
#6198 Connecting cable
#xxxx DeltaGraph Software License
#yyyy DeltaGraph User Manual


Base mechanics 33 x 14 x 6 (h) cm ( 13 x 5.5 x 2.4 inches) 0.85 kg ( 1.8 lbs)
Electronics 27 x 23 x 8 cm (10.6 x 9 x 3.1 inches)
Total weight 2.8 kg (5.9 lbs)

Measurement of surface tension and surface pressure


Wilhelmy method using a small diameter ( 0.51 mm) special alloy wire. No artefactual hysteresis as when using the conventional Pt-plates. No drying and accumulation of salt which cause significant errors when filter paper is used.

Dynamic range 0 to 300 mN/m
Resolution 10 µN/m
Temperature sensor Automatic monitoring and display of temperature in the course of the experiment, resolution 0.1 degrees (optional feature)
Temperature control A heat control plate which connects to a circulating heat bath is available as an optional feature


Materials Metal alloy and high purity PTFE. Several designs available. Also user-defined designs are routinely made.
Volume 300 µl in surface pressure measurements. Subphase can be magnetically stirred.