P9416 100ml

Nitrocellulose membrane (1UN18ER100025NT)
was purchased from Sartorius (Göttingen, Germany). Aqueous
suspension of single-layer GO (S1319112702) was purchased from Global
Graphene Group (Dayton, OH, USA). According to the supplier, this
2D material displays an average lateral size around 50 nm and its
C/O ratio is around 1. Tween 20 (P9416-100ML) and phosphate buffer
saline (PBS) tablets (P4417-100TAB) were purchased from Sigma-Aldrich
(Saint Louis, MI, USA). FITC Conjugation Kit Fast-Lightning-Link (ab188285)
was purchased from Abcam (Cambridge, UK). According to previously
reported procedures,^{11 (link),18 (link)} anti-SLD monoclonal antibody
and SLD peptide were produced by our team at the Universidad Autónoma
de Guerrero (Chilpancingo, Guerrero, Mexico). Vaginal swab samples
were collected by “Servicio de Diagnóstico Integral
en la detección Oportuna del Cancer Cérvico Uterino”
at Universidad Autónoma de Guerrero (Chilpancingo, Guerrero,
Mexico). Signed consent was obtained from those women who participated
in this research. Wax patterns were printed using a ColorQube 8085
from Xerox (Stanford, CT, USA). A hot plate StableTemp from Cole-parmer
(Vernon Hills, IL, US) was used to heat and fabricate the paper-based
devices. All the fluorescent micrographs were acquired through a Cytation
5 multimodal reader from BioTek (Winooski, VT, USA).

Three biological replicates (each with two technical replicates) of 1 mL of PBR cultures were harvested at different time points, mixed with 2.5 μL 2% Tween20 (Sigma, P9416-100ML) to help cell pelleting, centrifuged at 18,407 g at 4°C, and stored in −80°C after removal of supernatant. Cell pellets were later thawed, resuspended in 1 mL of HPLC grade methanol (100%, Sigma, 34860-4L-R), vortexed for 1 min, incubated in the dark for 5 min at 4°C, and centrifuged at 15,000 g at 4°C for 5 min. Supernatant containing pigments was analyzed at 470, 652, 665 nm in a spectrophotometer (IMPLEN Nonophotometer P300) for carotenoids and chlorophyll a/b concentrations in μg mL⁻¹ using the following equations: Chl a + Chl b = 22.12*A₆₅₂ + 2.71*A₆₆₅, Chl a = 16.29*A665 – 8.54*A652, and Chl b = 30.66*A652 – 13.58*A665^{124 (link)}, and carotenoids = (1000*A470 – 2.86*Chl a – 129.2*Chl b)/221^{125 (link)}.

Pigments were quantified as described before [23 (link)]. Three biological replicates of 1 mL of PBR cultures (around 2 × 10⁶ cells mL⁻¹) grown under normal condition of 25 °C were harvested, mixed with 2.5 μL of 2% Tween20 (Sigma, P9416-100ML) to help cell pelleting, centrifuged at 18,407× g at 4 °C to remove supernatant. Cell pellets were resuspended in 1 mL of HPLC grade methanol (100%, Sigma, 34860-4L-R), vortexed for 1 min, incubated in the dark for 5 min at 4 °C, and centrifuged at 15,000× g at 4 °C for 5 min. Top supernatant containing pigments was analyzed at 470, 652, 665 nm in a spectrophotometer (IMPLEN Nonophotometer P300) for carotenoids and chlorophyll a/b concentrations in μg mL⁻¹ using the following equations: Chl a + Chl b = 22.12xA₆₅₂ + 2.71xA₆₆₅, Chl a = 16.29xA₆₆₅ − 8.54xA₆₅₂, and Chl b = 30.66xA₆₅₂ − 13.58xA₆₆₅ [94 (link)], and carotenoids = (1000xA₄₇₀ − 2.86xChl a − 129.2xChl b)/221 [95 (link)].