Showing papers by "Nicholas A. Peppas published in 2021"

Engineering precision nanoparticles for drug delivery

Abstract: In recent years, the development of nanoparticles has expanded into a broad range of clinical applications. Nanoparticles have been developed to overcome the limitations of free therapeutics and navigate biological barriers - systemic, microenvironmental and cellular - that are heterogeneous across patient populations and diseases. Overcoming this patient heterogeneity has also been accomplished through precision therapeutics, in which personalized interventions have enhanced therapeutic efficacy. However, nanoparticle development continues to focus on optimizing delivery platforms with a one-size-fits-all solution. As lipid-based, polymeric and inorganic nanoparticles are engineered in increasingly specified ways, they can begin to be optimized for drug delivery in a more personalized manner, entering the era of precision medicine. In this Review, we discuss advanced nanoparticle designs utilized in both non-personalized and precision applications that could be applied to improve precision therapies. We focus on advances in nanoparticle design that overcome heterogeneous barriers to delivery, arguing that intelligent nanoparticle design can improve efficacy in general delivery applications while enabling tailored designs for precision applications, thereby ultimately improving patient outcome overall.

A combinational chemo-immune therapy using an enzyme-sensitive nanoplatform for dual-drug delivery to specific sites by cascade targeting.

Abstract: Nanoparticle-based drug delivery faces challenges from the imprecise targeted delivery and the low bioavailability of drugs due to complex biological barriers. Here, we designed cascade-targeting, dual drug-loaded, core-shell nanoparticles (DLTPT) consisting of CD44-targeting hyaluronic acid shells decorated with doxorubicin (HA-DOX) and mitochondria-targeting triphenylphosphonium derivative nanoparticle cores loaded with lonidamine (LND) dimers (LTPT). DLTPT displayed prolonged blood circulation time and efficiently accumulated at the tumor site due to the tumor-homing effect and negatively charged hyaluronic acid. Subsequently, the HA-DOX shell was degraded by extracellular hyaluronidase, resulting in decreased particle size and negative-to-positive charge reversal, which would increase tumor penetration and internalization. The degradation of HA-DOX further accelerated the release of DOX and exposed the positively charged LTPT core for rapid endosomal escape and mitochondria-targeted delivery of LND. Notably, when DLTPT was used in combination with anti-PD-L1, the tumor growth was inhibited, which induced immune response against tumor metastasis.

Precise control of synthetic hydrogel network structure via linear, independent synthesis-swelling relationships.

Abstract: Hydrogel physical properties are tuned by altering synthesis conditions such as initial polymer concentration and polymer-cross-linker stoichiometric ratios. Traditionally, differences in hydrogel synthesis schemes, such as end-linked poly(ethylene glycol) diacrylate hydrogels and cross-linked poly(vinyl alcohol) hydrogels, limit structural comparison between hydrogels. In this study, we use generalized synthesis variables for hydrogels that emphasize how changes in formulation affect the resulting network structure. We identify two independent linear correlations between these synthesis variables and swelling behavior. Analysis through recently updated swollen polymer network models suggests that synthesis-swelling correlations can be used to make a priori predictions of the stiffness and solute diffusivity characteristics of synthetic hydrogels. The same experiments and analyses performed on methacrylamide-modified gelatin hydrogels demonstrate that complex biopolymer structures disrupt the linear synthesis-swelling correlations. These studies provide insight into the control of hydrogel physical properties through structural design and can be used to implement and optimize biomedically relevant hydrogels.

Epitope-imprinted polymers: Design principles of synthetic binding partners for natural biomacromolecules.

Abstract: This work was supported by Project NORTE-01-0145-FEDER-000021 supported by the Norte Portugal Regional Operational Program (NORTE 2020), under the PORTUGAL 2020 Partnership Agreement, through the European Regional Development Fund (ERDF); by the European Union Framework Program for Research and Innovation HORIZON 2020, under the Twinning grant agreement no. 810850–Achilles, European Research Council grant agreement no. 772817; and by FCT/MCTES (Fundacao para a Ciencia e a Tecnologia/Ministerio da Ciencia, Tecnologia, e Ensino Superior) through PhD grant PD/BD/143039/2018 for S.P.B.T., financed through the Doctoral Program in Advanced Therapies for Health (PATH) (FSE/POCH/ PD/169/2013), project PTDC/NAN-MAT/30595/2017, and individual contract 2020.03410. CEECIND for R.M.A.D. N.A.P. acknowledges support from the Cockrell Family Chair Foundation; the Institute for Biomaterials, Drug Delivery, and Regenerative Medicine; and the UT-Portugal Collaborative Research Program.

Miniaturized Needle Array-Mediated Drug Delivery Accelerates Wound Healing.

Abstract: A major impediment preventing normal wound healing is insufficient vascularization, which causes hypoxia, poor metabolic support, and dysregulated physiological responses to injury. To combat this, the delivery of angiogenic factors, such as vascular endothelial growth factor (VEGF), has been shown to provide modest improvement in wound healing. Here, the importance of specialty delivery systems is explored in controlling wound bed drug distribution and consequently improving healing rate and quality. Two intradermal drug delivery systems, miniaturized needle arrays (MNAs) and liquid jet injectors (LJIs), are evaluated to compare effective VEGF delivery into the wound bed. The administered drug's penetration depth and distribution in tissue are significantly different between the two technologies. These systems' capability for efficient drug delivery is first confirmed in vitro and then assessed in vivo. While topical administration of VEGF shows limited effectiveness, intradermal delivery of VEGF in a diabetic murine model accelerates wound healing. To evaluate the translational feasibility of the strategy, the benefits of VEGF delivery using MNAs are assessed in a porcine model. The results demonstrate enhanced angiogenesis, reduced wound contraction, and increased regeneration. These findings show the importance of both therapeutics and delivery strategy in wound healing.

Epitope‐imprinted nanoparticles as transforming growth factor‐β3 sequestering ligands to modulate stem cell fate

Abstract: S.P.B.T. and R.M.A.D. contributed equally to this work. The authors acknowledge the financial support from project NORTE-01-0145-FEDER-000021 supported by Norte Portugal Regional Operational Program (NORTE 2020), under the PORTUGAL 2020 Partnership Agreement, through the European Regional Development Fund (ERDF); the European Union Framework Program for Research and Innovation HORIZON 2020, under the Twinning grant agreement no. 810850 – Achilles, European Research Council grant agreement no. 772817, Marie Sklodowska-Curie Actions grant agreement no. 676338; FCT/MCTES (Fundacao para a Ciencia e a Tecnologia/Ministerio da Ciencia, Tecnologia, e Ensino Superior) for the PhD grant PD/BD/143039/2018 for S.P.B.T., financed through the Doctoral Program in Advanced Therapies for Health (PATH) (FSE/POCH/PD/169/2013), project PTDC/NAN-MAT/30595/2017, and UT-Portugal Collaborative Research program. Schematics in Figures 1, 3, and 4 were created with BioRender.com.

Innovations in Biomaterial Design toward Successful RNA Interference Therapy for Cancer Treatment.

Abstract: Gene regulation using RNA interference (RNAi) therapy has been developed as one of the frontiers in cancer treatment. The ability to tailor the expression of genes by delivering synthetic oligonucleotides to tumor cells has transformed the way scientists think about treating cancer. However, its clinical application has been limited due to the need to deliver synthetic RNAi oligonucleotides efficiently and effectively to target cells. Advances in nanotechnology and biomaterials have begun to address the limitations to RNAi therapeutic delivery, increasing the likelihood of RNAi therapeutics for cancer treatment in clinical settings. Herein, innovations in the design of nanocarriers for the delivery of oligonucleotides for successful RNAi therapy are discussed.

Solute Transport Dependence on 3D Geometry of Hydrogel Networks.

Abstract: Hydrogels are used in drug delivery applications, chromatography, and tissue engineering to control the rate of solute transport based on solute size and hydrogel-solute affinity. Ongoing modeling efforts to quantify the relationship between hydrogel properties, solute properties, and solute transport contribute toward an increasingly efficient hydrogel design process and provide fundamental insight into the mechanisms relating hydrogel structure and function. However, here we clarify previous conclusions regarding the use of mesh size in hydrogel transport models. We use 3D geometry and hydrogel network visualizations to show that mesh size and junction functionality both contribute to the mesh radius, which determines whether a solute can diffuse within a hydrogel. Using mesh radius instead of mesh size to model solute transport in hydrogels will correct junction functionality-dependent modeling errors, improving hydrogel design predictions and clarifying mechanisms of solute transport in hydrogels.

High-Throughput FRAP Analysis of Solute Diffusion in Hydrogels

Abstract: Increasingly accurate mathematical models have been developed to relate solute and hydrogel properties to solute diffusion coefficients in hydrogels, primarily by comparing solute sizes and hydroge...

Electrostatic and Covalent Assemblies of Anionic Hydrogel-Coated Gold Nanoshells for Detection of Dry Eye Biomarkers in Human Tears.

Abstract: Although dry eye is highly prevalent, many challenges exist in diagnosing the symptom and related diseases. For this reason, anionic hydrogel-coated gold nanoshells (AuNSs) were used in the development of a label-free biosensor for detection of high isoelectric point tear biomarkers associated with dry eye. A custom, aldehyde-functionalized oligo(ethylene glycol)acrylate (Al-OEGA) was included in the hydrogel coating to enhance protein recognition through the formation of dynamic covalent (DC) imine bonds with solvent-accessible lysine residues present on the surface of select tear proteins. Our results demonstrated that hydrogel-coated AuNSs, composed of monomers that form ionic and DC bonds with select tear proteins, greatly enhance protein recognition due to changes in the maximum localized surface plasmon resonance wavelength exhibited by AuNSs in noncompetitive and competitive environments. Validation of the developed biosensor in commercially available pooled human tears revealed the potential for clinical translation to establish a method for dry eye diagnosis.