Knitting Thread Devices: Detecting Candida albicans Using Napkins and Tampons

Area of Science:

• Biotechnology
• Analytical Chemistry
• Microbiology

Background:

• Urinary tract infections (UTIs) disproportionately affect women, particularly in low-resource settings.
• Accurate and accessible diagnostics are crucial for equitable healthcare outcomes.
• Current diagnostic methods for vulvovaginal candidiasis can be costly and inaccessible.

Purpose of the Study:

• To develop a frugal, in situ microbial detection system for Candida albicans.
• To create a microfluidic-thread-based analytical device (μTAD) for point-of-care diagnostics.
• To enable early detection of vulvovaginal candidiasis for improved women's health.

Main Methods:

• Fabrication of microfluidic-thread-based analytical devices (μTADs) using multifilament cotton threads.
• Optimization of a mercerization method using heptane wash for enhanced reagent absorption.
• Impregnation of threads with a substrate (l-proline β-naphthylamide) for enzymatic detection of Candida albicans.

Main Results:

• A robust and facile mercerization method was established.
• The μTAD system detected Candida albicans via a colorimetric change.
• The assay demonstrated a limit of detection of 0.58 × 10^6 cfu/mL within 10 minutes.
• The device showed high stability and a long shelf life.

Conclusions:

• The developed thread-based assay offers a promising, low-cost solution for detecting Candida albicans.
• This technology has the potential to improve healthcare equity for women in underserved communities.
• The discreet and disposable nature of the device supports self-testing for taboo diseases.