Implementing Quality Control for the Fluorescent Coating of Intravenous Catheters

Team: Aaron Bigelow, Porter Ellis, Melissa Wiggins

Sponsor: Merit Medical

I. Abstract

The hydrophilic coating of Merit Medical’s Prelude IDeal trans-radial catheter is necessary for its biocompatibility. A qualitycontrol protocol was developed to ensure that 80% of thecatheter was coated, meeting FDA standards

II. Introduction

Merit Medical currently uses a Congo Red Dye test to verify thecoverage of the hydrophilic coating of their intravenous catheters.This dye is toxic, and each tested catheter is discarded, regardlessof the result [1]. If 14% of the batch fails, the entire batch isdiscarded, resulting in significant financial losses. To addressthese concerns, the fluorescent particle [2] was added to thecoating to aid in analysis (Figure 4). A specialized camera under UVconditions was implemented for analysis. Tests using a dark boxwill be conducted to ensure the fluorescent coating hascomparable or better results to the Congo Red Dye test.

III. Methods

Aggie Black Box Appara tus (ABBA) Design

  • 3D-printed the lid, box, and gear system (two stages) out of black PLA plastic
  • Removed supports using a precision knife and assembled box Assembled rotation mechanism with stepper motor, IR receiver, IR transmitter, and Arduino unit
  • Wrote and compiled the rotation mechanism code Configured the mechanism to receive IR signal, which initiates rotation

Image Capture and Processing

  • Used Teledyne DALSA Linea Color GigE line scan camera [3] to replace the Congo Red Dye test
  • Analyzed images of the catheter to detect spots where the coating was not applied properly
  • Stitched together several images, creating one image for the entire circumference of the catheter
  • A Python code took the images and analyzed them to verify the coating met industry standards

IV. Results

ABBA:

Using black PLA filament, the Aggie Black Box Apparatus (ABBA) was 3D-printed to accommodate the Line Scan Camera, Step Motor Configuration, and UV light. (Figure 1, 2)

Arduino:

Using the Arduino IDE, the Arduino unit was configured to simultaneously rotate the catheter and trigger an image capture.

Line Scan Camera:

Using the Sapera LT CamExpert software [4], the Line Scan Camera was configured to receive an analog trigger from the Arduino. The camera was also configured to detect the amount of light being fluoresced from the catheter, which will be used to analyze the integrity of the coating (Figure 3). Coating integrity is shown by the color difference between the coated and uncoated portions.

Figure 1: First Prototype of the ABBA with Arduino

Figure 1: First Prototype of the ABBA with Arduino

Figure 2: Current iteration of ABBA witha paper catheter

Figure 2: Current iteration of ABBA witha paper catheter

Figure 3: Image Captured by Line Scan Camera of Fluorescing IDeal Catheter

Figure 3: Image Captured by Line Scan Camera of Fluorescing IDeal Catheter

Figure 4: Prelude IDeal trans-radial cathetercoated in 1:15 ratio of coating to fluorescent particle

Figure 4: Prelude IDeal trans-radial cathetercoated in 1:15 ratio of coating to fluorescent particle

V. Conclusions & Discussion

Conclusions

The ABBA functions as intended, creating a dark environment to improve image capture of the fluorescing catheter. The Arduino also functioned as intended, delivering a trigger to the Line Scan Camera in sequence with the rotation of the stepper motor. The camera is calibrated to capture sufficient images of the catheter. However, the combination of the slightly fluorescent catheter and a dim UV flashlight hindered image capture. A proof of concept using a paper catheter was provided instead.

Discussion

Being printed out of PLA filament, the ABBA suffered some imperfections in the first iteration, necessitating a reprint. It was also discovered that the fluorescent particle decayed over time, requiring us to coat another series of catheters for testing. The Line Scan Camera uses an archaic software that is difficult to navigate. This combined with poor lighting hindered our progress towards processing images of the coating.

VI. Future Work

  • Cytotoxicity testing
  • Hemolysis testing
  • Image analysis of fluorescing catheter
  • A better light source for ABBA

VII. References

  1. Hernández-Zamora, M., Martínez-Jerónimo, F., Cristiani-Urbina, E., & Cañizares-Villanueva, R. O. (2016). Congo red dye affects survival and reproduction in the cladoceran Ceriodaphnia dubia. Effects of direct and dietary exposure. Ecotoxicology (London, England), 25(10), 1832–1840. https://doi.org/10.1007/s10646-016-1731-
  2. Thermo Scientific. (2015). Dyed Fluorescent and Colored Polymer Microsphere Suspension SDS (MSDS No. 1) (p. 12). Fremont, CA.
  3. Teledyne DALSA. (2018, August 18). Linea Color GigE Camera User Manual. Waterloo, Ontario, Canada. https://www.teledynedalsa.com/en/products/imaging/cameras/linea/
  4. Teledyne DALSA. (2018, March 6). Sapera LT CamExpert. Sapera LT SDK. computer software. St-Laurent, Quebec, Canada. https://www.teledynedalsa.com/en/products/imaging/vision-software/sapera-lt/
  5. Semple, S. (2019). Black 3.0 - the world’s blackest black acrylic paint. Culture Hustle USA. Dorset, England. https://www.culturehustleusa.com/products/black-3-0-the-worlds-blackest-black-acrylic-paint-150ml?variant=41128741175473