A5030940127- Advanced biosensing and bioanalysis techniques
- Gold and Silver Nanoparticles Synthesis and Applications
- Biosensors and Analytical Detection
- Photoacoustic and Ultrasonic Imaging
- Nanoplatforms for cancer theranostics
- Advanced Nanomaterials in Catalysis
- Infection Control and Ventilation
- SARS-CoV-2 detection and testing
- Optical Imaging and Spectroscopy Techniques
- Luminescence and Fluorescent Materials
- Supramolecular Self-Assembly in Materials
- Polymer Surface Interaction Studies
- COVID-19 and healthcare impacts
- Oral microbiology and periodontitis research
- Aerosol Filtration and Electrostatic Precipitation
- Polydiacetylene-based materials and applications
- Bone Tissue Engineering Materials
- Dental Radiography and Imaging
- Infection Control in Healthcare
- Advanced Polymer Synthesis and Characterization
- Conducting polymers and applications
- Virus-based gene therapy research
- Burn Injury Management and Outcomes
- Cleft Lip and Palate Research
- Molecular Junctions and Nanostructures
University of California, San Diego
2020-2025
Massachusetts Institute of Technology
2025
N95 decontamination protocols and KN95 respirators have been described as solutions to a lack of personal protective equipment. However, there are few material science studies that characterize the charge distribution physical changes accompanying disinfection treatments, particularly heating. Here, we report filtration efficiency, dipole density, fiber integrity before after various methods. We found filter layers in maintained their without any deformations during disinfection. The were...
Abstract The transmission of SARS‐CoV‐2 coronavirus has led to the COVID‐19 pandemic. Nucleic acid testing while specific limitations for mass surveillance. One alternative is main protease (M pro ) due its functional importance in mediating viral life cycle. Here, we describe a combination modular substrate and gold colloids detect M via visual readout. strategy involves zwitterionic peptide that carries opposite charges at C‐/N‐terminus exploit recognition by . Autolytic cleavage releases...
Photoacoustic (PA) imaging holds great promise as a noninvasive modality. Gold nanorods (GNRs) with absorption in the second near-infrared (NIR-II) window have emerged excellent PA probes because of their tunable optical absorption, surface modifiability, and low toxicity. However, pristine GNRs often undergo shape transition upon laser illumination due to thermodynamic instability, leading reduced signal after few seconds imaging. Here, we report monodisperse GNR-melanin nanohybrids where...
We report the peptide-programmed fractal assembly of silver nanoparticles (AgNPs) in a diffusion-limited aggregation (DLA) mode, and this change morphology generates significant color change. show that peptides with specific repetitions defined amino acids (i.e., arginine, histidine, or phenylalanine) can induce coalescence AgNPs (20 nm) into hyperbranched structure (AgFSs) (∼2 μm). The dynamic process was systematically investigated, extinction nanostructures be modulated from 400 to 600 nm...
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a serious threat to human health and lacks an effective treatment. There urgent need for both real-time tracking precise treatment of the SARS-CoV-2-infected cells mitigate ultimately prevent viral transmission. However, selective triggering therapeutic process in infected remains challenging. Here, we report main protease (Mpro)-responsive, mitochondrial-targeting, modular-peptide-conjugated probe (PSGMR) imaging inhibition via...
Plant viral nanoparticles (plant VNPs) are promising biogenetic nanosystems for the delivery of therapeutic, immunotherapeutic, and diagnostic agents. The production plant VNPs is simple highly scalable through molecular farming in plants. Some important advances VNP nanotechnology include genetic modification, disassembly/reassembly, bioconjugation. Although effective, these methods often involve complex time-consuming multi-step protocols. Here, we report a versatile supramolecular coating...
Abstract Stability issues in membrane-free coacervates have been addressed with coating strategies, but these approaches often compromise the permeability of coacervate. Here we report a facile approach to maintain both stability and using tannic acid then demonstrate value this enzyme-triggered drug release. First, develop size-tunable via self-assembly heparin glycosaminoglycan tyrosine arginine-based peptides. A thrombin-recognition site within peptide building block results release upon...
Patchy nanoparticles featuring tunable surface domains with spatial and chemical specificity are of fundamental interest, especially for creating three-dimensional (3D) colloidal structures. Guided assembly regioselective conjugation polymers have been widely used to manipulate such topography on nanoparticles; however, the processes require presynthesized specialized polymer chains elaborate conditions. Here, we show how small molecules can form 3D patches in aqueous environments a single...
Surface ligands play a critical role in controlling and defining the properties of colloidal nanocrystals. These aspects have been exploited to design nanoparticle aggregation-based colorimetric sensors. Here, we coated 13-nm gold nanoparticles (AuNPs) with large library (e.g., from labile monodentate monomers multicoordinating macromolecules) evaluated their aggregation propensity presence three peptides containing charged, thiolate, or aromatic amino acids. Our results show that AuNPs...
The recent synthesis of two-dimensional (2D) polyaramid (PA) polymers has shown that they exhibit remarkable mechanical and gas barrier properties. However, new methods are necessary to enable the efficient measurement discoidal sizes 2D polyaramids tracking their growth over time during reaction. Herein, we employ 1H NMR peak analysis aromatic proton end group regions characterize 2D-PA from monomeric precursors, alongside purification using two-stage filtration washing steps. ratio protons...
We present a strategy for constructing activatable photoacoustic imaging (PAI) probes in vivo enzyme activity measurements, based on dissociation previously applied to vitro sensing. Unlike conventional nanoparticle aggregation strategies, minimizes false positives and functions effectively complex biological environments. Overcoming the challenge of dissociating nanostructure aggregates, which arises from strong van der Waals forces at short distances, we demonstrate controlled assembly...
Photoacoustic (PA) imaging has proved versatile for many biomedical applications from drug delivery tracking to disease diagnostics and postoperative surveillance. It recently emerged as a tool accurate real-time heparin monitoring avoid bleeding complications associated with anticoagulant therapy. However, molecular-dye-based application is limited by high concentration requirements, photostability, strong background hemoglobin signal. We developed polydopamine nanocapsules (PNCs) via...
Plasmonic coupling via nanoparticle assembly is a popular signal-generation method in bioanalytical sensors. Here, we customized an all-peptide-based ligand that carries anchoring group, polyproline spacer, biomolecular recognition, and zwitterionic domains for functionalizing gold nanoparticles (AuNPs) as colorimetric enzyme sensor. Our results underscore the importance of module, which enables SARS-CoV-2 main protease (Mpro) to recognize peptidic on nanosurfaces subsequent plasmonic...
Abstract 3D‐bioprinted skin‐mimicking phantoms with skin colors ranging across the Fitzpatrick scale are reported. These tools can help understand impact of phototypes on biomedical optics. Synthetic melanin nanoparticles different sizes (70–500 nm) and clusters fabricated to mimic optical behavior melanosome. The absorption coefficient reduced scattering comparable real human skin. Further content distribution in versus skins validated via photoacoustic (PA) imaging. PA signal phantom be...
There is a need for surveillance of COVID-19 to identify individuals infected with SARS-CoV-2 coronavirus. Although specific, nucleic acid testing has limitations in terms point-of-care testing. One potential alternative the nonstructural protease (nsp5, also known as Mpro/3CLpro) implicated viral replication but not incorporated into virions. Here, we report divalent substrate novel design, (Cys)2–(AA)x–(Asp)3, interface gold colloids specific presence Mpro leading rapid and colorimetric...
We report the reversible aggregation of silver nanoparticle (AgNP) assemblies using combination a cationic arginine-based peptide and sulfur-capped polyethylene glycol (PEG). The formation dissociation aggregates were studied by optical methods electron microscopy. clusters depends on sequence PEG size. A molecular weight 1 kDa for was optimal dissociation. most important feature this method is that it can operate in complex biofluids such as plasma, saliva, bile, urine, cell media, or even...
Organic nanomaterials increasingly generate interest from diverse fields spanning fundamental and clinical research, biotechnology, nanomedicine. are exceptionally versatile, with applications in several domains: molecular imaging, pharmaceutical formulations, image-guided therapies. Unlike inorganic nanomaterials, these materials offer distinct advantages, such as facile tunability composition or surface functionalization, excellent biocompatibility, controlled release, so on. Here,...
Gold nanorods (GNRs) have attracted great interest for photo-mediated biomedicines due to their tunable and high optical absorption, photothermal conversion efficiency facile surface modifiability.GNRs that efficient absorption in second near-infrared (NIR-II) window hold further promise bio-applications low background signal from tissue deep penetration.However, bare GNRs readily undergo shape deformation (termed as 'melting effect') during the laser illumination losing unique localized...
Facemasks in congregate settings prevent the transmission of SARS-CoV-2 and help control ongoing COVID-19 global pandemic because face coverings can arrest respiratory droplets. While many groups have studied as personal protective equipment, these droplets also serve a diagnostic fluid to report on health state; surprisingly, studies from this perspective are quite limited. Here, we determined concentration distribution aerosolized saliva (via α-amylase levels) captured various coverings....
We report the reversible aggregation of gold nanoparticles (AuNPs) assemblies via a di-arginine peptide additive and thiolated PEGs (HS-PEGs). The AuNPs were first aggregated by attractive forces between citrate-capped surface arginine side chains. found that HS-PEG thiol group has higher affinity for AuNP surface, thus leading to redispersion colloidal stability. In turn, there was robust obvious color change due on/off plasmonic coupling. assemblies' dissociation directly related...
Plasmonic nanoparticles produce a localized surface plasmon resonance (LSPR) under optical excitation. The LSPR of can shift in response to changes the local dielectric environment and color change. This change be observed by naked eye due exceptionally large extinction coefficients (108–1011 M–1 cm–1) plasmonic nanoparticles. Herein, we investigate shifts (i.e., change) three unique gold–silver core–shell nanoparticle structures their upon aggregation. Aggregation is induced...
Electrostatic interactions are a key driving force that mediates colloidal assembly.
Better insights into the fate of membraneless organelles could strengthen understanding transition from prebiotic components to multicellular organisms. Compartmentalized enzyme reactions in a synthetic coacervate have been investigated, yet there remains gap interactions with as substrate hub. Here, we study how molecularly crowded nature affects embedded protease. We design oligopeptide-based coacervates that comprise an anionic Asp-peptide (D10) and cationic Arg-peptide (R5R5) proteolytic...