cgm

Overview

Blood glucose meters are an important and growing industry worldwide. This category of products includes blood glucose monitoring test strips and readers, and continuous glucose monitors (CGMs). Wearable glucose monitors, also known as CGMs, are essential to patients and medical professionals. They assist patients in tracking their health instantly and aid doctors in diagnosing and treating complex medical issues.

As more people get older and testing improves, it will be challenging for manufacturers to handle the higher demand. Forward thinking manufacturers are already analyzing current market forces and strategizing about how they can successfully meet the CGM opportunity.

Of the many technologies used to produce CGMs, fluid dispensing is pivotal and deserves focus. Dispensing applications include applying reagents to test strips and adhesives to bond components for CGM readers.

Fluid dispensing technologies help manufacturers apply precise amounts of fluids at the correct positions on CGM substrates and test strips. This increases throughput yields, while reducing fluid waste and part rejects. Plus, many of these solutions provide a smooth transition from manual to semi-automated to fully automated manufacturing processes. In this way, organizations can implement dispensing automation solutions in a stepwise manner as market conditions require.

Fluids Used

Typically, CGM manufacturers use cyanoacrylates and UV-cure adhesives in their manufacturing process. Silicone oils are used for component lubrication.

Manufacturers prefer UV-cure adhesives because they change color when cured. UV-cure adhesives provide manufacturers with a visual confirmation that the adhesive has completely cured. In addition, UV-cure adhesives deliver faster cure times and very accurate fluid dispense placement on substrates.

In some cases, CGM manufacturers need to lubricate their parts. For this need, silicone oils are used. Likewise, some manufacturers need to dispense conductive petroleum jelly onto sensors.

Although traditional blood glucose strips are not a CGM, people widely use them to monitor blood glucose levels. These strips change color based on the amount of glucose in the blood, using chemicals in the strip. They contain enzymes, coenzymes, mediators, and indicators in the strip.  Blood drops on reagents turn blood glucose into a readable signal for the meter.

For blood glucose strip manufacturing, a chemical reagent is necessary to detect glucose in the blood. To do this, manufacturers must consider a wide differential of solution viscosity and solvent properties. Some fluids include tetrahydrofuran, PHF, and isobutanol. Often it is a proprietary chemistry that needs to be dispensed onto conjugate pads on a test strip.

Application Requirements

Both CGM and traditional blood glucose strips are heavily regulated medical devices. Both products must pass stringent quality standards and provide accurate readings under adverse conditions.

In order to meet the quality standards on CGM and Blood Glucose Technologies, manufacturers require extremely precise and repeatable fluid dispensing solutions. Application requirements include micro-dispensing at specific locations on the substrates consistently. The deposit size tolerances for these applications are generally very tight, sometimes as small as ± 1%. Applying the same amount of fluid at the correct location every time is paramount to generating high-quality CGMs because the potential consequences for faulty CGMs or test strips is very high. Fluid Dispensing Solutions

Manual Fluid Dispensing

For CGM manufacturers, Nordson EFD’s manual fluid dispensing solutions provide an entry-point investment.

The Ultimus I fluid dispenser is used by CGM producers to dispense conductive petroleum jelly onto sensors inside the reader devices. CGM manufacturers also use the Ultimus II dispenser with PTFE-lined dispense tips and blue pistons to dispense cyanoacrylate fluids. Fast cure times of the cyano make it appealing but also tricky to dispense. This is why a disposable syringe is often better to use than a valve with mechanical parts.

Semi-Automated Fluid Dispensing

As CGM production needs increase, semi-automated fluid dispensing solutions are advantageous. Semi-automated solutions are operator based. They offer better control, greater accuracy, and improved repeatability. These systems provide improved control for higher volume, precision manufacturing.

CGM manufacturers can configure their semi-automated fluid dispensing solution based on their manufacturing needs. A proven CGM manufacturing setup features a tabletop automated dispensing system and a dispensing head such as the PICO Pµlse® XP jet valve, xQR41 Series MicroDot™ needle valve, or 752V series diaphragm valve. CGM manufacturers choose this combination of Nordson EFD fluid dispensing solutions because it enables them to improve efficiency and save production time.

For example, the PICO XP jet valve is used to dispense UV-cure adhesives for bonding an implantable device’s chassis or body together. Jet valves eliminate the need for Z-axis movement, therefore increasing the speed at which a fluid can be applied. This makes it a great option for high-volume production.

Recently, a CGM manufacturer selected a Nordson EFD automated fluid dispensing solution to manufacture a blood glucose reader. The design required joining two injection molded sides of the blood glucose reader. In addition, the design specified encapsulating the device’s circuit board to secure and protect it.

The manufacturer used UV-cure fluids for these applications.

Joining the two sides of the blood glucose reader is a complex operation. The device is joined at a molded ledge on both sides of the injection molded parts. The robot dispenses fluids onto the narrow ledge, following the outline of the injected molded part.

The CGM manufacturer used a 3-Axis PROPlus Series automated fluid dispensing robot to meet its objectives. The system provided excellent X, Y, and Z-axis repeatability, and the speed needed to meet higher production output needs. The constant closed-loop feedback provided actionable data for improving throughput.

The 3-axis robot was fitted with a PICO XP jetting system because of the precision and repeatability needed to apply fluids on the injection molded parts. The micro-level dispensing capability of 0.5 nL enabled the CGM manufacturer to apply fluids in compound arcs and lines on the blood glucose reader at high speeds for high volume production demands.

Spray valves are also commonly used in CGM production to lubricate small parts with silicone oil. Nordson EFD’s 781 spray valve is a common tool for this application. It is typically mounted onto a 3-axis semi-automatic dispensing robot for batch production.

Conclusion

CGM manufacturers must balance the need for high volume demand with meeting demanding regulatory requirements. To succeed, manufacturers need to securely attach parts and dispense reagents as the demand for blood glucose monitoring increases.

In the next 10 years, healthcare providers will require many CGM devices for different patient care purposes. A strong fluid dispensing capability affords manufacturers the speed, quality, and flexibility needed for CGMs bonding applications.