Stain-free interferometric phase microscopy correlation with DNA fragmentation stain in human spermatozoa.

Acridine orange (AO) staining is used to diagnose DNA fragmentation status in sperm cells. Interferometric phase microscopy (IPM) is an optical imaging method based on digital holographic microscopy that provides quantitative morphological and refractive index imaging of cells in vitro without the need for staining. We have imaged sperm cells using stain-free IPM in order to estimate different cellular parameters, such as acrosome dry mass and size, in addition to an embryologist evaluation according to the World Health Organization (WHO)-2010 criteria.

Individual sperm selection by microfluidics integrated with interferometric phase microscopy.

The selection of sperm cells possessing normal morphology and motility is crucial for many assisted reproductive technologies (ART), especially for intracytoplasmic sperm injection (ICSI), as sperm quality directly affects the probability of inducing healthy pregnancy. We present a novel platform for real-time quantitative analysis and selection of individual sperm cells without staining. Towards this end, we developed an integrated approach, combining interferometric phase microscopy (IPM), for stain-free sperm imaging and real-time automatic analysis based on the sperm cell 3D morphology and contents, with a disposable microfluidic device, for sperm selection and enrichment.

Localized measurements of physical parameters within human sperm cells obtained with wide-field interferometry.

We developed a new method to identify the separate cellular compartments in the optical path delay (OPD) maps of un-labeled spermatozoa. This was conducted by comparing OPD maps of fixed, un-labeled spermatozoa to bright field images of the same cells following labeling. The labeling enabled us to identify the acrosomal and nuclear compartments in the corresponding OPD maps of the cells.

Depth selective acousto-optic flow measurement.

Optical based methods for non-invasive measurement of regional blood flow tend to incorrectly assess cerebral blood flow, due to contribution of extra-cerebral tissues to the obtained signal. We demonstrate that spectral analysis of phase-coded light signals, tagged by specific ultrasound patterns, enables differentiation of flow patterns at different depths. Validation of the model is conducted by Monte Carlo simulation.

Intraoperative Cerebral Autoregulation Assessment Using Ultrasound-Tagged Near-Infrared-Based Cerebral Blood Flow in Comparison to Transcranial Doppler Cerebral Flow Velocity: A Pilot Study.

Objective: This was a pilot study comparing the ability of a new ultrasound-tagged near-infrared (UT-NIR) device to detect cerebral autoregulation (CA) in comparison to transcranial Doppler (TCD).

Design: An unblinded, prospective, clinical feasibility study.

Setting: Tertiary-care university hospital cardiac surgical operating rooms.

Microfluidic ELISA: on-chip fluorescence imaging.

Fluorescent reactions of a heterogeneous sandwich enzyme-linked immunoassay (ELISA) in an all-PDMS [poly (dimethylsiloxane)] microfluidic device were detected using a cooled charge coupled device (CCD) camera interfaced with an epifluorescence microscope. The study represents preliminary efforts to integrate biochemical reactions and detection on-chip using the "hybrid" detection approach. In initial experiments, the PDMS chip microsensor was successfully used to quantify a model analyte (sheep IgM) with sensitivity down to 17nM.

Use of DNA and peptide nucleic acid molecular beacons for detection and quantification of rRNA in solution and in whole cells.

DNA and peptide nucleic acid (PNA) molecular beacons were successfully used to detect rRNA in solution. In addition, PNA molecular beacon hybridizations were found to be useful for the quantification of rRNA: hybridization signals increased in a linear fashion with the 16S rRNA concentrations used in this experiment (between 0.39 and 25 nM) in the presence of 50 nM PNA MB.