ZTS1240 transfer standard for zeta and also size?

von Ulf Nobbmann, Tuesday, 14th September 2021

The Zeta transfer standard has been a feature of our online store for quite a while. The latest version, the ZTS1240, consists of a box of ten syringes. We prefill the syringes, so there is no need to dilute or prepare the sample in any way. Simply inject it into your instrument. (Well, to be more exact, first into a suitable cuvette, which you place into your instrument).

photo of a pre-filled syringe with zeta transfer standard, good for zeta potential and size measurements. photo taken by Kyle Williams.
ZTS1240 Zeta transfer standard, about -40mV and 300nm diameter

Transfer standard: Good for zeta only…?

We had zeta potential measurements in mind as the primary use for the Zeta Transfer Standard. This is a good sample to verify the zeta potential performance of your electrophoretic light scattering instrument. We recommend the DTS1270 folded capillary cell. And, by the way, this is not just for the Zetasizer, it’s for any electrophoretic light scattering ELS instrument. Use it to verify the zeta performance of your equipment. You can find the specification of the zeta range you should expect on the label. It is 40mV ±15%, or in other words 40mV ± 5.8mV. Other parameters of relevance are the zeta deviation and the conductivity. The zeta deviation is typically under 10mV. The conductivity should be about 0.3 mS/cm, which is milli Siemens per centimeter.

Table of zeta potential verification criteria, for use with the ZTS1240 transfer standard
Typical zeta potential verification values for the ZTS1240 transfer standard [ZXP2.2]

How about size?

You might wonder if this zeta transfer standard is also suitable for size measurements? Yes, it is! The ZTS1240 transfer standard can be a fine performance verification reference for dynamic light scattering (DLS) instruments. Since the syringes were initially designed for zeta only, we do not specify the size of the box. Nevertheless, the self-install test uses the size from DLS to verify performance. So here are the criteria for this test. The z-average size must be between 288 and 328nm in diameter.

  • A typical mean value for the DLS is 300nm for the size of the particles in the transfer standard.
  • The polydispersity index should be below 0.1 as a typical value.

So you can easily test your DLS system with this syringe standard.

Table of DLS sizing verification criteria, for use with the ZTS1240 transfer standard, in nay dynamic light scattering system.
Typical size verification values for the ZTS1240 transfer standard [ZXP2.2]

More detail for size on the transfer standard…

Note: This is not a primary standard and we only supply it with a generic measurement result. Although we do test each batch to ensure it is within specification. A certificate containing the batch number of the sample is available on request. The size verification criteria are for the latest generation systems and software. The classic Nano does not have an equivalent to Run Retention, since this parameter applies only to adaptive correlation. Therefor the method between classic Nano and Zetasizer Advance series is slightly different, see ZTS1240 methods and MSDS.

PS: There is a range of specific size standards (for example 60nm NIST traceable Latex, Polystyrene; also on offer in a range of diameters: 20nm, 30nm, 40nm, 50nm, 60nm, 70nm, 80nm, 90nm, 100nm, 125nm, 150nm, 200nm, 220nm, 240nm, 269nm, 300nm, 350nm, 400nm, 450nm, 500nm, 600nm, 700nm, 800nm, 900nm ) available on the webstore. However, these often require preparation/dilution.

Previously

Do you have any questions? Please email me ulf.nobbmann@malvernpanalytical.com – Thanks! Opinions are those of the author. Our editorial team modifies them occasionally.

Access the Store