Biology subjects

Astete, C.

Publications and source records attributed to Astete, C..

3 recordsLinked to original sources

bioRxiv2026

On-demand, reversible blood-brain barrier opening via electrical activation of piezoelectric nanoparticles for targeted brain drug delivery

Delivering therapeutics to the brain remains one of the most persistent challenges in medicine, because the blood-brain barrier (BBB) excludes over 98% of small-molecule drugs and virtually all biologics from the central nervous system (CNS). We developed electrical BBB modulation (eBBB), an on-demand platform combining vascular-targeting poly-L-lactic acid nanoparticles with high-definition transcranial direct current stimulation to achieve spatially and temporally controlled BBB opening. eBBB produced localized, reversible increases in BBB permeability confined to the stimulated cortex, with the opening area tunable via electrode geometry. This transient window enhanced regional delivery of a small-molecule drug, full-length immunoglobulins, and adeno-associated viral vectors, which are cargo classes otherwise completely excluded by the intact BBB. Neurovascular unit architecture was preserved with no lasting histological damage. Integrating a biodegradable nanomaterial with a clinically evaluated stimulation technology, eBBB offers a programmable, minimally invasive strategy for regional CNS drug delivery across brain malignancies and neurological disorders. One sentence summaryElectrical activation of piezoelectric nanoparticles reversibly opens the blood-brain barrier for minimally invasive drug delivery to targeted cortical regions.

bioengineering↗

bioRxiv2023

Method for assessing coating uniformity of angioplasty balloons coated with poly(lactic-co-glycolic acid) nanoparticles loaded with quercetin

SignificanceDrug-coated angioplasty balloons (DCBs) are used to treat peripheral artery disease, and proper dosage depends on coating characteristics like uniformity and number of layers. AimQuantify coating uniformity and correlate fluorescence intensity to drug loading for DCBs coated with 5, 10, 15, or 20 layers of poly(lactic-co-glycolic acid) nanoparticles (NPs) entrapped with quercetin. ApproachImages of DCBs were acquired using fluorescence microscopy. Coating uniformity was quantified from histograms and horizontal line profiles, and cracks on the balloons were measured and counted. Fluorescence intensity was correlated with the drug loading of quercetin found from gravimetric analysis coupled with high-performance liquid chromatography (HPLC). ResultsHigher numbers of coating layers on DCBs may be associated with less uniform coatings. Cracks in the coating were present on all balloons, and the length of cracks was not significantly different between balloons coated with different numbers of layers or balloons coated with the same number of layers. A strong positive correlation was identified between fluorescence intensity and drug loading. ConclusionThere may be a relationship between the number of NP layers and the uniformity of the coating, but further investigation is needed to confirm this. Fluorescence intensity appears to be a strong predictor of drug loading on DCBs coated with quercetin-entrapped NPs, demonstrating that fluorescent imaging may be a viable alternative to drug release studies.

bioengineering↗

bioRxiv2022

Nanoparticle coatings for controlled release of quercetin from an angioplasty balloon

Peripheral artery disease (PAD) is a systemic vascular disease of the legs that results in a blockage of blood flow from the heart to the lower extremities. Now one of the most common causes of mortality in the U.S., the first line of therapy for PAD is to mechanically open the blockages using balloon angioplasty. Coating the balloons with antiproliferative agents can potentially reduce vessel re-narrowing, or restenosis after surgical intervention, but current drug-coated balloons releasing chemotherapy agents like paclitaxel have in some cases shown increased mortality long-term. Our aim was to design a novel drug-coated balloon using a polymeric nanodelivery system for a sustained release of polyphenols that reduce restenosis but with reduced toxicity compared to chemotherapy agents. Poly (lactic-co-glycolic acid) (PLGA) nanoparticles with entrapped quercetin, a dimethoxy quercetin (rhamnazin), as well as quercetin conjugated to PLGA, were developed. Balloon catheters were coated with polymeric nanoparticles using an ultrasonic method, and nanoparticle characteristics, drug loading, coating uniformity and drug release were determined. The adhesion of nanoparticles to vascular smooth muscle cells and the antiproliferative effect of nano-delivered polyphenols were also assessed. Of the nanoparticle systems tested, those with covalently attached quercetin provided the most sustained release over a 6-day period. Although these particles adhered to cells to a smaller extent compared to other nanoparticle formulations, their attachment was resistant to washing. These particles also exhibited the greatest anti-proliferative effect. In addition, their attachment was not altered when the cells were grown in calcifying conditions, and in PAD tissue calcification is typically a condition that impedes drug delivery. Moreover, the ultrasonic coating method generated a uniform balloon coating. The polymeric nanoparticle system with covalently attached quercetin developed herein is thus proposed as a promising platform to reduce restenosis post-angioplasty.

pharmacology and toxicology↗