Objective:

To evaluate the effectiveness of the deep-ultraviolet ptychographic pocket-scope (DART) for imaging biological samples without chemical stains.

Key Findings:

• DART can image centimeter-scale areas with submicron resolution and millimeter-scale depth of field.
• It revealed nuclear and cytoplasmic features in unstained lung fine-needle aspiration smears that were not visible with standard microscopy.
• The system enabled label-free visualization of leukocytes and quantitative separation of cell types in blood samples.
• DART supports 'virtual staining' by converting quantitative measurements into images resembling traditional staining methods.

Interpretation:

DART offers a promising alternative to traditional staining methods in pathology by providing intrinsic molecular contrast and high-resolution imaging without altering samples.

Limitations:

• The study may require further validation in clinical settings.
• Potential limitations in the range of sample types that can be effectively imaged.

Conclusion:

DART represents a significant advancement in label-free imaging techniques, with potential applications in diagnostic laboratories.