Fig 1.
Components of smartphone microscope.
(A) Ball lens mounted onto the mounting plate and then to the smartphone camera. (B) Measurement set up.
Fig 2.
A flow chart describing different steps involved in the spike recovery experiment.
Table 1.
Field of view (FOV) of the smartphone microscope.
Fig 3.
Images and data obtained with different illumination sources.
(A) Representative images of (oo)cysts taken using smartphone microscope with 1 mm ball lens with white LED light illumination and (B) smartphone flashlight illumination. The representative cyst and oocyst in A are shown within white and yellow circles, respectively. A scale bar of 50 μm is shown in A and also applies for B. (C) The measured contrast for (oo)cysts. The error bar in C represent the standard deviation of triplicate measurements.
Fig 4.
Images and data obtained with two different staining methods.
(A) Representative images of Lugol’s iodine and (B) methylene blue staining. The images were taken at 10 min of staining. (C) The average intensity of (oo)cysts under white LED light source at different time intervals (D) A plot of contrast versus incubation time for methylene blue and Lugol’s iodine staining.
Table 2.
Percentage recovery of Cryptosporidium and Giardia using smartphone, commercial brightfield, and fluorescence microscopes.
Fig 5.
Prevalence of Giardia and Cryptosporidium in vegetable and water samples measured by smartphone microscopic method.
A) Cryptosporidium and B) Giardia. The numbers within each bar graph represent the number of samples.
Table 3.
Singular and mixed prevalence of (oo)cysts in vegetable and water samples measured by three different microscopic methods.