Design of a microfluidic paper-based device for analysis of biomarkers from urine samples on diapers

Abstract

Among all infections, urinary tract infections (UTI) are one of the most common. Nowadays the procedures to analyze urine and consequently detect UTI are often painful and time-consuming. Recent studies about microfluidic paper-based devices have developed the interest of researchers due their outstanding characteristics. In this paper is presented a novel design for a microfluidic paper-based device for screening and analysis of multiple biomarkers from urine samples on diapers. The device consists on a set of eight layers. It was designed based on the previous attempts to improve and overcome some problems detected as the continuous entrance of fluids, the possibility of contamination and the invalidity of results due to communication between different reagent pads. One approach was create a "self-locking" mechanism that closes the sample inlet in approximately four minutes solving the first two problems. Furthermore, is important that comfort is guaranteed, hence a device with a total thickness of 5,3 mm is presented. This device can keep the results for eight hours and can be used as a low-cost and more effective alternative than conventional methods being a strategy with potential for the diagnostic and analysis of biological samples in the future improving healthcare.

Paper and thread as media for the frugal detection of urinary tract infections (UTIs)

“…Another effort in using diapers to detect biomarkers in urine was undertaken by Couto and Dong [67]. An eight-Fig.…”

“…Although the current literature has limited if any examples of wearable UTI detection devices [76,131,132], wearable systems which use urine [133][134][135][136] or saliva [137][138][139] for testing can be adapted for similar use. The current boom in computing can also be exploited to greatly improve the sensitivity and specificity of testing by using smartphones for DIY image processing of the final result [66,77].…”

“…Another effort in using diapers to detect biomarkers in urine was undertaken by Couto and Dong [ 67 ]. An eight-layer device was produced which can utilize a self-locking technique to close the sample inlet within 5 min.…”

“…1 filter paper, chloride assay kit. sulfanilamide, N-(1-Naphthyl) ethylenediamine and citric acid (Nitrite detection), smart-phone – NO 2 - , Cl - Artificial urine Colorimetric 0.13 mM (NO 2 - ) [ 66 ] Wax printing Acrylic base, wooden chopstick as rotation axis and three layers of Whatman filter paper, biotin, HRP, anti- E. coli Turntable with six reagent zones E. coli (anti-E. coli) E. coli in Luria-Bertani (LB) medium Colorimetric 10 5 CFU/ml [ 70 ] Bee wax screen printing Kraft paper, acrylate, Poly (methyl methacrylate) (PMMA), polytetrafluoroethylene (PTFE), filter paper Set of eight layers one on top of the other, Test layers made of filter paper cut in a parallelepiped shape, reagent pads glued between wax barriers by adhesives Glucose, protein, occult blood, nitrite, leukocyte esterase Urine Colorimetric – [ 67 ] CO 2 laser cutting, Whatman filter paper, solid wax, PMMA Star patterned paper with hydrophobic barriers and hydrophilic channels connected with eight reagent zones Nitrite Spiked urine Colorimetric 0.5 ppm [ 64 ] CO 2 laser cutting Whatman filter No.1, specific aptamer for S. aureus , Au/Pt bimetallic nanocluster, TMB Y shaped channel with one end for control and another for the target Staphylococcus aureus Human serum Colorimetric 80 CFU/mL [ 71 ] Inkjet printing of Paraffin ink Whatman filter paper (grade 1), colorimetric substrate PRO and indicator DCA Circular device Candida albicans (L-proline aminopeptidase) Spiked water Colorimetric 0.86 × 10 6 CFU/mL [ 72 ] – Whatman 1 filter paper, Whatman 1 chromatography paper, resazurin sodium salt, smart-phone …”

Urinalysis Using a Diaper-Based Testing Device

“…Seo et al presented a diaper-embedded and self-powered UTI monitoring sensor module [ 10 ]. Couto et al described an eight-layer microfluidic paper-based device for screening and analysis of multiple biomarkers from urine samples on diapers [ 11 , 12 ].…”