Droplet Lab

10/21/2026

Every model carries a hidden assumption. The 'k' fudge factor is where many contact line models simplify the real shape of the three phase contact line. Prof. Alidad Amirfazli walks through what that costs and when it matters: https://dropletlab.com/surface-science-hub/fundamentals-of-wetting-adhesion-webinar/?utm_source=facebook&utm_medium=social&utm_campaign=wetting_adhesion_webinar

10/16/2026

Something we don't say enough as an instrument maker: our product isn't right for everyone, and we'd rather you know that up front.

If your lab has a $20,000-$100,000+ budget and needs peer-review-grade precision with real-time dynamic wetting capture, the KRUSS DSA100E is genuinely the better choice - 0.1 degree accuracy, up to 3450 frames per second.

The Dropometer is built for a different situation: labs and QC teams that need dependable, research-grade contact angle data at $4,990, without needing frame-by-frame dynamic capture or a six-figure budget line.

We wrote a full buyer's guide to help you figure out which category your work actually falls into, including where we honestly rank ourselves against the premium instruments out there. What's the biggest factor for your lab when picking measurement equipment: precision, speed, price, or something else? Curious to hear how other labs weigh it.

Full write-up:

Compare contact angle goniometer options for advanced research: full measurement scope, optics and demonstrated accuracy for peer review.

10/14/2026

Measure the same surface with two different methods and you can get two different answers. The receding angle especially is sensitive to how the measurement is run. Prof. Alidad Amirfazli explains why method discipline matters: https://dropletlab.com/surface-science-hub/fundamentals-of-wetting-adhesion-webinar/

10/09/2026

Repellency is not mobility. A high contact angle tells you a drop beads up, not that it will roll off, and two surfaces can show the same angle yet shed water completely differently. Prof. Alidad Amirfazli explains the distinction: https://dropletlab.com/surface-science-hub/fundamentals-of-wetting-adhesion-webinar/

10/07/2026

Real talk about the Murdoch University case study we just published.

When the team at Murdoch University started using the Dropometer to measure soil contact angles for their sustainable farming research, the first results weren't consistent. Depending on how the software's placement mode was set, the same soil sample was giving different readings.

We worked with Dr. Tona Sanchez-Palacios, who holds a Murdoch-CSIRO Fellowship, and her team from their first inquiry in July 2025 through February 2026 to track down what was happening. Turned out to be a calculation error tied to placement mode. Once we fixed it, the instrument returned left and right contact angles of 120.67° and 125.03° on their soil sample, and the team validated those numbers against a KRUSS DSA100E.

We could have told you this was smooth from day one. It wasn't, and we'd rather tell you what actually happened. Have you run into calibration or measurement quirks with your own lab instruments? Curious how other research teams handle that kind of troubleshooting.

Full write-up:

How a Murdoch University soil team made contact angle calculate on rough, porous soil using a tilted baseline, extended detection, and tight image cropping

09/29/2026

Here's something that surprises a lot of people working with polypropylene: treating the surface (plasma, corona, etc.) doesn't create a permanent change. PP has a habit called hydrophobic recovery, where the surface starts reverting back toward its untreated, low-energy state within minutes to hours after treatment.

So if you treat a batch of PP parts in the morning and don't bond them until later in the shift, there's a real chance the surface has already started sliding back toward 'not ready for adhesive' by the time bonding actually happens.

The fix is simple: check the surface right before you bond, not just right after you treat it. A quick contact angle reading tells you whether the window is still open.

We put together a worked example showing what that drift can look like over a few hours (illustrative only, not a real production run, since every site's numbers will differ) -- and it's a good reminder that a treated surface is more like a perishable ingredient than a permanent fix.

Anyone run into this with your own PP bonding process? Curious how people are timing treatment and bonding on their lines.

Full write-up:

Bond hard-to-stick polypropylene reliably. Verify surface treatment and energy with contact angle testing before adhesives or printing.

09/28/2026

If you formulate with surfactants and you are dosing to a value from a reference table, it is worth checking.

That number was measured in pure water, at a temperature that probably is not yours, in a matrix that definitely is not yours. Critical micelle concentration shifts with temperature, with water hardness, and with everything else in the mix.

The failure this causes is quiet. Dose above it and you are paying for surfactant that is forming micelles rather than doing the job you wanted. Dose below it and wetting goes inconsistent at a concentration the datasheet says should be fine. Neither shows up as a defect. Both show up as cost.

Questions welcome in the comments.

Full write-up:

Discover accurate Critical Micelle Concentration (CMC) assessment techniques using automated surface tension measurements.

09/23/2026

The top 5 to 10 angstroms of a surface decide how it wets, bonds, and repels, and bulk material specs miss it completely. Prof. Alidad Amirfazli explains why the outermost molecular layer is the thing worth measuring. Full webinar: https://dropletlab.com/surface-science-hub/fundamentals-of-wetting-adhesion-webinar/

09/18/2026

Here's something we don't say enough: you shouldn't have to just trust us on accuracy.

Dropometer's measurement approach has actually been benchmarked against the KRUSS DSA100E — one of the most established contact angle goniometers on the market — in peer-reviewed research (Chen, Muros-Cobos & Amirfazli, 2018, Review of Scientific Instruments, with a companion study in Colloids and Surfaces A).

So when we say Dropometer gives you reliable numbers at a fraction of the cost of a $30,000+ instrument, that's not just a sales pitch — it's something you can go read and check for yourself.

Curious how the comparison holds up spec by spec? We wrote up the full breakdown: camera specs, weight, price, and all. Link in comments. What would you want to see tested next?

Full write-up: https://dropletlab.com/resources/buying-guides/contact-angle-goniometers/dropometer-vs-kruss-dsa100s-dsa100e/ | Study: https://pubs.aip.org/aip/rsi/article-abstract/89/3/035117/368179/Contact-angle-measurement-with-a-smartphone | Companion study: https://www.sciencedirect.com/science/article/abs/pii/S0927775717307744

Compare the Dropometer to the KRÜSS DSA100S and DSA100E: contact angle, surface energy and tension specs, price, and when each instrument is the right buy.