Evaluation of Intradermal and Subcutaneous Infusion Set Performance Under 24-Hour Basal and Bolus Conditions.

Background: This study sought to assess the function and delivery reliability of intradermal (ID) infusion sets used with commercial insulin pumps.

Method: Healthy subjects (n = 43) were randomized to either ID or subcutaneous (SC) arms, and received basal/bolus placebo delivery for 24 hours. Subjects received 4 of 8 infusion set combinations (ID: microneedle design A or B, with 2 pump brands [Animas or MiniMed]; SC: Teflon Quickset or steel Rapid-D, Animas pump only, with or without overtaping) and were evaluated for pump occlusion alarms, fluid leakage, pain, and tissue tolerability.

Characterizing normal-use temperature conditions of pumped insulin.

In this study, the temperature profiles of insulin pump reservoirs during normal wear conditions across multiple seasons were characterized. Thermocouples secured in reservoirs filled with insulin diluent were loaded in infusion pumps worn by volunteers. Reservoir and ambient environmental temperature data and activity levels were logged during the course of normal daily activities in February (winter), April (spring), and August (summer).

Microfluidic cytometer for the characterization of cell lysis.

Blood cytometry and intercellular analysis typically requires lysis as a preparatory step, which can alter the results of downstream analyses. We fabricated a microfluidic cytometer to characterize erythrocyte lysis kinetics. Forward light scatter from erythrocytes was used for enumeration at specific locations on a microfluidic chip.

Aptamer-conjugated nanoparticles for selective collection and detection of cancer cells.

We have developed a method for the rapid collection and detection of leukemia cells using a novel two-nanoparticle assay with aptamers as the molecular recognition element. An aptamer sequence was selected using a cell-based SELEX strategy in our laboratory for CCRF-CEM acute leukemia cells that, when applied in this method, allows for specific recognition of the cells from complex mixtures including whole blood samples. Aptamer-modified magnetic nanoparticles were used for target cell extraction, while aptamer-modified fluorescent nanoparticles were simultaneously added for sensitive cell detection.