Kidney stone crystal

Leonard studied photography and biology at Hampshire College, where he explored leukocytes (white blood cells) on optical microscopes. Subsequent stints at University of Massachusetts and Cornell Medical College honed his skills and fostered a lifelong passion for electron microscopy.

During the economic downturn of the late 1980s Leonard started APL Microscopic to market his scientific images to pharmaceutical companies. His work has evolved to explore their aesthetic value too.

Breast cancer cells: HER-2 positive

Some of Leonard's subjects - like a cat's claw and budding grass - are charmingly domestic and easily acquired. Others are more sinister, like breast cancer cells. For human cells, Leonard procures specimens via an extensive network of physicians and researchers.

He examines samples with a field emission scanning electron microscope, which uses a focused beam of electrons to capture a digital image of topography and composition.

Microplankton: radiolarian

According to Leonard, every session with the microscope is unpredictable: "Every sample is different. Sometimes you cannot find what you're looking for [because] what you're looking for is not what you thought it would look like. Sometimes the sample gets ruined doing preparation and you have to start from square one. Sometimes you have a look and immediately see lots of what you like."

Bryozoan from the Indian Ocean (a micro-marine colony of individuals)

Andrew Paul Leonard's photographs capture the big personality of microscopic organisms.

Microplanton: Radiolarian

Human lymphocyte (white blood cell)

Shedding cat claw

Unknown collection of microplankton remnants

Microplankton: radioloarian (Saturnalis)

Microplankton: radiolarian

Microplankton: radiolarian

Synthetic fiber

Human lung tissue, showing alveoli, brachial and capillary

Carbon adhesive tape

Surface of human embryonic stem cell colony

Neuron

Cryptosporidium (parasite)

Cryptosporidium is a microscopic parasite that causes diarrhea. It is a leading cause of waterborne disease in the United States.

Kidney stone crystals

Monocyte-derived human dendritic cell undergoing apoptosis (programmed cell death)

Monocyte-derived human dendritic cell undergoing apoptosis (programmed cell death)

Toxoplasma gondii (cause of toxoplasmosis)

Toxoplasma gondii is a parasitic organism that reproduces only in cats and can infect most animals, including humans.

Parakeet feather

Budding grass

Microplankton: radiolarian

Radiolaria are single-celled aquatic animals that produce intricate and varied mineral skeletons.

Ruins of a radiolarian (microplankton)

Radiolaria skeletal remains make up a large part of the ocean floor as siliceous ooze.

Two human embryonic stem cells

Mosquito wing

Ruins of a radiolarian

Unidentified marine organism

Radiolaria scraps

Radiolarian surface

Folical stimulating hormone (FSH) drug

Andrew Paul Leonard

Pile of kidney stone crystals