A crosslinked polymer skin barrier film for moderate to severe atopic dermatitis: A pilot study in adults.

BACKGROUND: Occlusive treatments are a mainstay in atopic dermatitis (AD) management but may not be well tolerated or lack compliance. A comfortable, semiocclusive, artificial skin barrier that is well tolerated, provides protection, and reduces water loss is needed. OBJECTIVE: To evaluate the potential tolerability and therapeutic benefits of a crosslinked polymer layer (XPL) in adults with AD. METHODS: A single-center, open-label pilot study was conducted involving 10 subjects with moderate to severe AD. Subjects applied XPL up to twice daily for 30 days on a selected treatment area. Investigator's Global Assessment, clinical signs of eczema, and pruritus were assessed on days 1, 3, 5, 15, and 30. Film durability and patient satisfaction were also evaluated. RESULTS: Investigator's Global Assessment scores improved from moderate to severe at baseline to clear to almost clear in 8 of 9 patients at day 30. Pruritus improved from trace to severe itching (baseline) to all subjects having trace to no itching at day 30. There was 1 adverse event of mild exudative dermatitis. LIMITATIONS: The study was limited by small sample size, open-label design, and lack of control. CONCLUSION: XPL may be an effective adjuvant in AD treatment. A larger study with a control group is warranted.

An elastic second skin.

We report the synthesis and application of an elastic, wearable crosslinked polymer layer (XPL) that mimics the properties of normal, youthful skin. XPL is made of a tunable polysiloxane-based material that can be engineered with specific elasticity, contractility, adhesion, tensile strength and occlusivity. XPL can be topically applied, rapidly curing at the skin interface without the need for heat- or light-mediated activation. In a pilot human study, we examined the performance of a prototype XPL that has a tensile modulus matching normal skin responses at low strain (<40%), and that withstands elongations exceeding 250%, elastically recoiling with minimal strain-energy loss on repeated deformation. The application of XPL to the herniated lower eyelid fat pads of 12 subjects resulted in an average 2-grade decrease in herniation appearance in a 5-point severity scale. The XPL platform may offer advanced solutions to compromised skin barrier function, pharmaceutical delivery and wound dressings.

Improved vapor sensitivity by rationally designing fluorescent turn-on sensors.

We report a turn-on sensor framework with enhanced vapor sensitivity by increasing the sensor's response dynamic range via rational design of the sensor formulation. Using a fluorescent dye as the reporter, our approach begins by reducing sensor background fluorescence through the use of selected quenchers. Analyte interaction induces the onset of emission by interrupting the quenching interaction, thereby turning on the sensor. We demonstrate over an order of magnitude increase in vapor sensitivity for dimethyl methylphosphonate (a Sarin simulant) detection using a sensor containing inorganic oxides as a quencher for Nile Red dye. This approach was also used to develop a new sensor with improved sensitivity for methyl benzoate (a hydrolysis byproduct of cocaine, used to train drug-sniffing dogs). By generalization, additional candidate quenchers for Nile Red were identified based on Lewis acid/base interactions. This framework can be applied in parallel with other amplification strategies including mass transport incentive, one-analyte-to-multiple-reporter schemes or signal lasing to further increase sensor response amplitude.

Polysulfone-graft-poly(ethylene glycol) graft copolymers for surface modification of polysulfone membranes.

Amphiphilic graft copolymers having polysulfone (PSf) backbones and poly(ethylene glycol) (PEG) side chains were synthesized via reaction of an alkoxide formed from PEG and a base (sodium hydride) with chloromethylated polysulfone. The resulting polysulfone-graft-poly(ethylene glycol), PSf-g-PEG, materials were hydrophilic but water insoluble, rendering them potentially useful as biomaterial coatings. PSf-g-PEG films exhibited high resistance to protein adsorption and cell attachment. When used as an additive in PSf membranes prepared by immersion precipitation, the graft copolymer preferentially segregates to the membrane surface, delivering enhanced wettability, porosity and protein resistance compared to unmodified PSf membranes. The surface properties of PSf-g-PEG modified membranes render them desirable candidates for hemodialysis.