What is the availability/lead time of the Klarite SERS substrates?

We monitor stock carefully and aim to fulfil all orders within 3 days.

Can I use Klarite SERS substrates with solid samples?

SERS is a surface effect requiring adsorption (i.e. chemisorption or physisorption) of the molecule to the surface. Hence the Klarite substrates cannot be used with solid samples. It is first necessary to dissolve the sample in an appropriate solvent and then allow it to air dry. See Below:

Is it possible to put more than one sample on the substrates?

It depends on your application or test (e.g. solvent used). For small volumes (~1 µl) of water solutions 5 or more different drops can be deposited on a single 4 mm x 4 mm active area.

 

The shelf life is in excess of 2 years if the product is properly stored. It is recommended to store the substrates at fridge (<4º C or <39º F) or better at freezer temperatures (~-15º C or ~5º F)

 

How do I use the Klarite substrates?

A step by step guidance can be found in the Klarite 302 instructions

Correct substrate handling, molecule delivery and instrument settings are key to for a successful test. For any further technical support information please email the D3 team at info@d3technologies.co.uk we will be happy to advice.

 

The first step is to deliver the molecules of interest to the surface to obtain adsorption. The delivery method depends form the phase of the target analytes. For vapours and gases the spontaneous diffusion process will provide the delivery of the molecule to the surface. Exposing the surface to the vapour will suffice. The optimal adsorption conditions depend on the experimental conditions and on the physical characteristics of the vapour/molecules. Solutions can be delivered to the surface by pipettes or immersion. The nature of the solvent will determine the evaporation conditions and the subsequent molecule distribution on the surface. Please refer to the instruction for use manual for more information. For any further technical support information please email the D3 team at info@d3technologies.co.uk and we will be happy to advise.

 

What excitation wavelengths can I use Klarite with?

Klarite substrates are designed to work best in the red to near infrared wavelength, hence suitable for the common wavelengths 633 nm and 785nm. It is not suitable for wavelength <532 nm as the textured gold film becomes quite absorptive.

Why do I only see a small increase in my Raman signal when using Klarite?

The first step is always making sure that the experiment and instrument settings are correct. The most common cause for detecting small signal is the use of highly concentrated solutions. The signal detected by the instrument is only due to bulk Raman. To check if the signal is due to Raman rather than SERS detect signal from solution deposited on the flat gold handing areas of the Klarite chip. The SERS effect is unambiguously identified only when the signal is only detected on the Klarite active area and NOT on the flat gold. See below:

Why does R6G not work with Klarite substrates?

Rhodamine 6G is not the ideal molecule to use with gold Klarite substrates for several reasons. R6G is resonant at around 514 nm and our gold substrates are not optimized for this excitation wavelength. Also R6G does not bind to gold as well as it binds to silver.
If you were interested in looking at resonant dye molecules to test Klarite then we would suggest Nile blue as it is resonant at 785 nm or Nile red which is resonant at 633 nm. However resonant molecules are not the ideal analyte to assess the performance of SERS surfaces in general.

Which credit cards do D3 accept?

We accept Visa and Mastercard.

What is sCAL?

sCal is our silicon calibration standard. Each chip comes from the same silicon wafer, so it is the ideal product when accurate quantitative calibration of similar instruments are required.