Electrode Materials: Carbon Paste vs. Sputtered Gold

Unlock the Power of Electrode Materials

Revolutionizing [Diabetic Test Strips](/sell-diabetic-supplies/)

Most electrochemical test strips use one of two electrode designs: Screen Printed Carbon (Thick-Film) or Sputtered Gold (Thin-Film). The first is an ink printed onto the strip. The second is a very thin metal layer laid down in a vacuum and then cut into shape. Printing came first in home meters. A 2008 review names screen printing, along with redox mediators (chemicals that shuttle electrons from the enzyme to the electrode), as the two breakthroughs behind MediSense's pen-sized ExacTech meter [1].

Carbon Paste: The Budget-Friendly Option

Carbon Paste is the low-cost route. Carbon and metal pastes are screen-printed onto a plastic or ceramic base, which is much simpler and cheaper than the platinum rod and wire electrodes used before [1]. The method scales well: in China, strips with screen-printed carbon sensors had been in commercial production since 1994, and a 2009 review counted about 10 companies making meters and strips there [2]. The usual trade-off is that a carbon ink conducts less well than metal and its printed surface is less uniform, which can cost some precision. We haven't found a published study that measures how much this matters in a finished commercial strip.

Sputtered Gold: The Premium Powerhouse

Sputtered Gold strips are made by depositing a thin gold film in a vacuum and then patterning it, sometimes with a laser (laser ablation), to get tightly controlled electrode shapes. LifeScan's OneTouch Verio strip is one documented example. LifeScan researchers describe thin-film gold and palladium electrodes facing each other across a thin spacer: the glucose reaction happens at the palladium electrode, and the gold electrode is used to estimate hematocrit, the share of blood made up of red cells [3]. In their own testing, all 2,700 results across hematocrit levels of 19% to 61% met the ISO accuracy criteria the authors applied [3]. That is one manufacturer's study of one system, not a comparison with carbon strips. We couldn't confirm from FDA summaries or manufacturer pages which other current brands use sputtered gold or laser ablation.

What Makes Sputtered Gold a Winner

• Small sample volumes. The OneTouch Verio strip needs 0.4 µL of blood [4], and Abbott's FreeStyle Lite strip needs 0.3 µL [5]. With sub-microliter samples common across major brands as of October 2026, sample size alone doesn't tell you what an electrode is made of.
• Electron transfer. Gold is often described as giving faster, more predictable electron transfer kinetics than printed carbon. We haven't found a study that isolates this effect in commercial strips.
• Coefficients of Variation (CV). CV is the spread of repeated results expressed as a percentage of their average. A smoother electrode surface should help keep it low, but published CVs describe whole systems, not the electrode by itself.

So a gold electrode doesn't make a strip more accurate on its own. Accuracy comes from the whole system: enzyme, electrode design and meter software together [3]. Independent testing against the ISO 15197:2013 accuracy standard is a better guide than the metal inside.