Antibody-Conjugated Polymersomes with Encapsulated Indocyanine Green J-Aggregates and High Near-Infrared Absorption for Molecular Photoacoustic Cancer Imaging.

Imaging plays a critical role in all stages of cancer care from early detection to diagnosis, prognosis, and therapy monitoring. Recently, photoacoustic imaging (PAI) has started to emerge into the clinical realm due to its high sensitivity and ability to penetrate tissues up to several centimeters deep. Herein, we encapsulated indocyanine green J (ICGJ) aggregate, one of the only FDA-approved organic exogenous contrast agents that absorbs in the near-infrared range, at high loadings up to ∼40% w/w within biodegradable polymersomes (ICGJ-Ps) composed of poly(lactide--glycolide--polyethylene glycol) (PLGA--PEG).

Glucose biosensors based on Michael addition crosslinked poly(ethylene glycol) hydrogels with chemo-optical sensing microdomains.

Continuous glucose monitoring (CGM) devices have the potential to lead to better disease management and improved outcomes in patients with diabetes. Chemo-optical glucose sensors offer a promising, accurate, long-term alternative to the current CGMs that require frequent calibration and replacement. Recently, we have proposed glucose sensor designs using phosphorescence lifetime-based measurement of chemo-optical glucose sensing microdomains embedded within alginate hydrogels.

Synthesis of Ultrasmall Synthetic Melanin Nanoparticles by UV Irradiation in Acidic and Neutral Conditions.

Synthetic melanin nanoparticles have value in metal chelation, photoprotection, and biocompatibility. Applications of these materials have been reported in optics, biomedicine, and electronics. However, precise size control has remained relatively difficult-especially for materials below 1000 nm.

Photoacoustic Imaging Quantifies Drug Release from Nanocarriers via Redox Chemistry of Dye-Labeled Cargo.

We report a new approach to monitor drug release from nanocarriers via a paclitaxel-methylene blue conjugate (PTX-MB) with redox activity. This construct is in a photoacoustically silent reduced state inside poly(lactic-co-glycolic acid) (PLGA) nanoparticles (PTX-MB@PLGA NPs). During release, PTX-MB is spontaneously oxidized to produce a concentration-dependent photoacoustic signal.

A cellulose-based photoacoustic sensor to measure heparin concentration and activity in human blood samples.

Heparin is an indispensable drug in anticoagulation therapy but with a narrow therapeutic window, which dictates regular testing and dose adjustment. However, current monitoring tools have a long turnaround time or are operator intensive. In this work, we describe a cellulose-based photoacoustic sensor for heparin.

A Mechanistic Investigation of Methylene Blue and Heparin Interactions and Their Photoacoustic Enhancement.

We recently reported a real-time method to measure heparin in human whole blood based on the photoacoustic change of methylene blue (MB). Intriguingly, the MB behaved unlike other "turn on" photoacoustic probes-the absorbance decreased as the photoacoustic signal increased. The underlying mechanism was not clear and motivated this study.

A Wearable Colorimetric Dosimeter to Monitor Sunlight Exposure.

The personal ultraviolet (UV) dosimeter is a useful measurement tool to prevent UV induced dermal damages; however, conventional digital dosimeters are either bulky or require external power sources. Here, a wearable, colorimetric UV film dosimeter that provides color transition, from purple to transparent, is reported to indicate the UV dose. The film dosimeter is made of a purple photodegradable dye ((2Z,6Z)-2,6-bis(2-(2,6-diphenyl-4H-thiopyran-4-ylidene)ethylidene)cyclohexanone or DTEC) blended in low density polyethylene film.

The characterization of an economic and portable LED-based photoacoustic imaging system to facilitate molecular imaging.

Photoacoustic imaging (PAI) is a non-invasive, high-resolution hybrid imaging modality that combines optical excitation and ultrasound detection. PAI can image endogenous chromophores (melanin, hemoglobin, etc.) and exogenous contrast agents in different medical applications.

Linearly polarized emission from self-assembled microstructures of mesogenic polythiophenes.

This work reports on linearly polarized photoluminescence and electroluminescence through spontaneous self-assembly of mesogenic polythiophenes under ambient conditions. A systematic structural variation and different alkyl chain lengths lead to three series of closely related mesogenic polythiophenes viz.; TPn, TNn and TVn.

A solution processable fluorene-fluorenone oligomer with aggregation induced emission enhancement.

Herein, we report a novel solution processable fluorenone based small molecule with an Aggregation Induced Emission Enhancement (AIEE) property. In contrast to previous reports, the presence of the fluorenone moiety in FF triggers the AIEE property.

"Click" polymerization on a self-assembled monolayer: a convenient approach to functionalize various surfaces with polytriazoles.

"Click" polymerization reaction has been performed on the functional self-assembled monolayer to incorporate polytriazoles. Ellipsometric and atomic force microscopic studies indicated a high degree of polymerization and fairly dense surface coverage. Band gap calculation revealed the possibility of its use as a semiconducting material.