This is to be used as a regularly updated post where I post links to new papers I think are of interest to the community.
Colorimetry in Chemical Analysis - Shows a large set of example on the kind of tests performed using colorimetry.
Low cost digital holographic microscope for 3-D cell imaging by integrating smartphone and DVD optical head - Paywall. This group have taken an imaging head from a DVD-player and used it to generate a 2 beam holographic microscope. While this might be a low cost setup I would guess that assembling it would be challenging.
A low-cost do-it-yourself microscope kit for hands-on science education - open access, contains video presentation. This paper describes the work of the BioBus, a nonprofit organization for science outreach and education based in New York City (www.biobus.org). they have used a benchtop microscope to engage and educate. The paper shows some matrices of engagements by the children.
Deep learning improves mobile-phone microscopy (Conference Presentation) - not open, contains video presentation. This is a summary of several publications by the Ozcan group out of UCLA who are doing some very impressive work, see more here.
Smartphone-based low-cost microscope with monolithic focusing mechanism - open access, describes the design of a single piece to hold and manipulate a phone (they made a mold that resembles plastic model aircraft look out of the box).