My name is Brandon Bell and I am the Process Engineer here at RheoSense. I am responsible for the production of the VROC® Initium product line and I wanted to take a few minutes to provide you a few tips and tricks that I have picked up to help you get the most out of your instrument.
Tip 1. VROC Sensor maintenance.
At the heart of your Initium lies your VROC chip. Just like the heart in your body, it requires care and maintenance. One of the most common problems we encounter when examining VROC Sensors is that a majority of the sensors fail due to lodged microscopic fibers within the flow channel, obstructing the flow of any samples. To avoid this from happening, it is essential that samples going through the chip have been properly and completely filtered for any micro particulates and fibers (less than 2μm). This not only includes your samples but even more importantly the cleaning solution, buffers, or solvents in the Solvent Jars. This is because during cleaning, a relatively large volume of solvent runs through the VROC Sensor.
Tip 2. Proper Sample Preparations.
One of the most common reasons for invalid or no useful data comes from improper sample preparations, as majority of errors stem from bubbles in the sample. To counteract sample loading errors, it is essential to centrifuge your sample in the RheoSense approved insert, which are individually tested for maximum reliability. As a general guideline we recommend at least 5 minutes at 10,000 rpms, but extending the duration will not hurt and may further help remove any lingering bubbles in your sample. Another common problem we see with sample preparation is the use of non-RheoSense approved vial and insert which do not meet our extremely high level of accuracy which may in the end effect your results.
Human error will always be a factor in any given experiment, but the most common error we see is the selection of the wrong protocols. Before starting any job, it is recommended that you double check to make sure that the solvent in the solvent jar matches the Sample Loading Protocol and cleaning Protocol that you have selected. The Initium has no way of detecting what solvents are in the solvent jars except for what you input into the Initium software and indication of any problems will show up as errors in your viscosity measurements.
Tip 4. Consumable Use Count.
To maintain proper care of your Initium and stay confident in your results, it is imperative to keep a watchful eye on the use counts of the consumables and replacing them when needed. This is because after those parts pass over their tested limits, we discovered that this can ultimately affect yours readings which can jeopardize the reliability of your instrument. Feel free to refer to our consumable list for parts, prices, and timetables here.
I hope these few tips and tricks have been helpful and if you ever need help or have any questions feel free to contact us at 1 (925) 866-3808 because we are always happy to make your measurements.