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Cordova, L. S.

Publications and source records attributed to Cordova, L. S..

2 recordsLinked to original sources

Rapid Prototyping of Microfluidic Devices with Stereolithographic 3D Printing

3D printing has become a prevalent technology in many fields such as manufacturing, architecture, and electronics. This additive manufacturing technique is also widely used for biomedical research and clinical applications to prototype or assemble biomedical devices and tools. 3D printing-based strategies for biocompatible materials offer greater design flexibility, enhanced versatility, and faster results than traditional fabrication techniques, advantages that could be especially beneficial to the development of microfluidic chips. The ability to simply and efficiently produce new chip molds from computer aided design (CAD) models would significantly transform the development process and expand its accessibility by removing the need for more complex and expensive lithography methods. However, with standard processing strategies, the use of 3D printed molds for casting functioning chips is limited by the poor quality of prints achievable with widely available 3D printers. To mitigate this issue and facilitate rapid microfluidic device prototyping, we have developed a simple procedure to print microfluidic molds using a stereolithographic (SLA) printer and produce functional polydimethylsiloxane (PDMS) microfluidic chips with height and width feature dimensions as low as 75 {micro}m. Molds printed using a commercially available liquid photopolymer-based resin and processed using our strategy exhibited high dimensional fidelity to intended designs and significantly reduced average surface roughness (< 3 {micro}m). Here, we describe a streamlined post-print processing workflow for SLA molds and its efficacy in reducing surface roughness while preserving dimensional fidelity and then demonstrate its utility by prototyping and optimizing a microfluidic extracellular vesicle (EV)-exchange platform. Graphical AbstractRapid prototyping of microfluidic device features using stereolithographic 3D printing. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=110 SRC="FIGDIR/small/662041v1_ufig1.gif" ALT="Figure 1"> View larger version (29K): org.highwire.dtl.DTLVardef@126ff02org.highwire.dtl.DTLVardef@1301c7forg.highwire.dtl.DTLVardef@19edb96org.highwire.dtl.DTLVardef@6256b5_HPS_FORMAT_FIGEXP M_FIG C_FIG

bioengineering↗

Size-tunable ICG-based contrast agent platform for targeted near-infrared photoacoustic imaging

Near-infrared photoacoustic imaging (NIR-PAI) combines the advantages of optical and ultrasound imaging to provide anatomical and functional information of tissues with high resolution. Although NIR-PAI is promising, its wide application is hindered by the limited availability of NIR contrast agents. J-aggregates (JA) made of indocyanine green dye (ICG) represents an attractive class of biocompatible contrast agents for PAI. Here, we present a facile synthesis method that combines ICG and ICG-azide dyes for producing contrast agent with tunable size down to 230 nm and direct functionalization with targeting moieties. The ICG-JA platform has a detectable PA signal in vitro that is two times stronger than whole blood and high photostability. The targeting ability of ICG-JA was measured in vitro using HeLa cells. The ICG-JA platform was then injected into mice and in vivo NIR-PAI showed enhanced visualization of liver and spleen for 90 minutes post-injection with a contrast-to-noise ratio of 2.42.

bioengineering↗