Liraglutide-loaded poly(lactic-co-glycolic acid) microspheres: Preparation and in vivo evaluation

Development of 1 Month Sustained-Release Microspheres Containing Liraglutide for Type 2 Diabetes Treatment

Liraglutide has been extensively applied in the treatment of type 2 diabetes mellitus (T2DM), but its 11-15 h half-life resulted in daily administration, which led to poor patient compliance. This study aimed to solve this problem by developing liraglutide-loaded microspheres with a 1 month sustained release prepared by the W1/O/W2 method combined with the premix membrane emulsification technique to improve therapeutic efficacy. Remarkably, we found that the amphiphilic properties of liraglutide successfully reduced the oil-water interfacial tension, resulting in a stable primary emulsion and decreasing the level of drug leakage into the external water phase. As a result, exceptional drug loading (>8%) and encapsulation efficiency (>85%) of microspheres were achieved. Furthermore, the uniformity in microsphere size facilitated an in-depth exploration of the structural characteristics of liraglutide-loaded microspheres. The results indicated that the dimensions of the internal cavities of the microspheres were significantly influenced by the size of the inner water droplets in the primary emulsion. A denser and more uniform cavity structure decreased the initial burst release, improving the release process of liraglutide from the microspheres. To evaluate the release behavior of liraglutide from microspheres, a set of in vitro release assays and in vivo pharmacodynamics were performed. The liraglutide-loaded microspheres effectively decreased fasting blood glucose (FBG) levels and hemoglobin A1c (HbA1c) levels while enhancing the pancreatic and hepatic functions in db/db mice. In conclusion, liraglutide sustained-release microspheres showed the potential for future clinical applications in the management of T2DM and provided an effective therapeutic approach to overcoming patient compliance issues.

Metal-polyphenol microgels for oral delivery of puerarin to alleviate the onset of diabetes

Puerarin (Pue) is a naturally bioactive compound with many potential functions in regulating blood glucose and lipid metabolism. However, the low bioavailability and rapid elimination in vivo limit the application of Pue in diabetic treatment. Here, we developed a metal-polyphenol-functionalized microgel to effectively deliver Pue in vivo and eventually alleviate the onset of diabetes. Pue was initially encapsulated in alginate beads through electrospray technology, and further immersed in Fe3+ and tannic acid solution from tannic acid (TA)-iron (Fe) coatings (TF). These constructed Pue@SA-TF microgels exhibited uniform spheres with an average size of 367.89 ± 18.74 µm and high encapsulation efficiency of Pue with 61.16 ± 1.39%. In vivo experiments proved that compared with free Pue and microgels without TF coatings, the biological distribution of Pue@SA-TF microgels specifically accumulated in the small intestine, prolonged the retention time of Pue, and achieved a high effectiveness in vivo. Anti-diabetic experimental results showed that Pue@SA-TF microgels significantly improved the levels of blood glucose, blood lipid, and oxidative stress in diabetic mice. Meanwhile, histopathological observations indicated that Pue@SA-TF microgels could significantly alleviate the damage to the liver, kidney, and pancreas in diabetic mice. Our study provided an effective strategy for oral delivery of Pue and achieved high anti-diabetic efficacy.

Optimized LC-MS/MS method for quantifying insulin degludec and liraglutide in rat plasma and Tissues: Application in pharmacokinetics and biodistribution

We present an ultra-performance liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for simultaneous detection of insulin degludec (I-Deg) and liraglutide (LIRA) in rat plasma and tissues, characterized by its sensitivity and selectivity. Chromatographic separation was achieved using an Acquity UPLC BEH C18 column, leveraging a mobile phase of acetonitrile and water (both with 0.1 % formic acid) under gradient elution over a run time of 7.5 min. The mass spectrometer operated in positive electrospray ionization multiple reaction monitoring (MRM) mode, tracking transitions of m/z 1221.6 → 641.6 for I-Deg, m/z 938.7 → 1064.1 for LIRA, and m/z 1184.7 → 454.4 for the internal standard. Validation ranged from 5 to 100 ng/mL, exhibiting robust linearity (r2 > 0.99) and limits of detection (LOD) of 1.63-2.02 ng/mL for I-Deg and 0.96-1.62 ng/mL for LIRA. Limits of quantification (LOQ) were 2.38-4.76 ng/mL for I-Deg and 3.22-4.40 ng/mL for LIRA. Notably, no significant matrix effects were detected. Stability was confirmed under various conditions, and precision metrics (intraday RSD 1.68-8.05 % for I-Deg and 1.11-7.69 % for LIRA; interday RSD 1.39-8.61 % for I-Deg and 1.06-8.83 % for LIRA) alongside accuracy (90.5-114.9 % for I-Deg and 92.7-113.7 % for LIRA) were within acceptable ranges. The method was successfully applied to pharmacokinetic and biodistribution studies following simultaneous subcutaneous administration of LIRA and I-Deg in rats.

Long-term antitrypanosomal effect of quinapyramine sulphate-loaded oil-based nanosuspension in T. evansi-infected mouse model

The goal of the present work consisted of the formulation development and evaluation of quinapyramine sulphate (QS)-loaded long-acting oil-based nanosuspension for improved antitrypanosomal effect. QS was transformed into a hydrophobic ionic complex using anionic sodium cholate (Na.C). The complex was characterized by FTIR, DSC, and XRD. Oil-based nanosuspension was prepared by dispersing the QS-Na.C complex in thixotropically thickened olive oil. The nanoformulation was found to be cytocompatible (82.5 ± 5.87% cell viability at the minimum effective concentration [MEC]) in THP-1 cell lines and selectively trypanotoxic (p < 0.0001). The pharmacokinetic studies of QS-Na.C complex-loaded oily nanosuspension showed 13.54-fold, 7.09-fold, 1.78-fold, and 17.35-fold increases in t1/2, AUC0-∞, Vz/F, and MRT0-ꝏ, respectively, as compared to free QS. Moreover, a 7.08-fold reduction in plasma clearance was observed after the treatment with the optimized formulation in Wistar rats. Furthermore, treatment with QS-Na.C complex-loaded oily nanosuspension (7.5 mg/kg) in T. evansi-infected mice model showed the absence of parasitaemia for more than 75 days after the treatment during in vivo efficacy studies. The efficacy of the treatment was assessed by observation of blood smear and PCR assay for DNA amplification. To conclude, our findings suggest that the efficient delivery of QS from the developed QS-Na.C complex-loaded oily nanosuspension could be a promising treatment option for veterinary infections against trypanosomiasis.

Recent Advances in the Preparation of Protein/peptide Microspheres by Solvent Evaporation Method

Protein/peptide drugs are extensively used to treat various chronic and serious diseases. The short half-life in vivo of protein and peptide as therapeutics drug limit the realization of complete effects. Encapsulating drugs in microspheres can slow the speed of drug release and prolong the efficacy of drugs. The solvent evaporation method is widely used to prepare protein/ peptide microspheres because of its facile operation and minimal equipment requirements. This method has several challenges in the lower encapsulation efficiency, fluctuant release profiles and the stabilization of protein/peptides, which researchers believe may be solved by adjusting the preparation parameter or formulation of microspheres. The article discusses the formulation parameters that govern the preparation of protein/peptide-loaded microspheres by the solvent evaporation method, which provides an overview of the current promising strategies for solvent evaporation for protein/peptide microspheres. The article takes parameter evaluation as the framework, facilitating subsequent researchers to quickly find possible solutions when encountering problems.

Combined effect of SDF-1 peptide and angiogenic cues in co-axial PLGA/gelatin fibers for cutaneous wound healing in diabetic rats

Skin regeneration is hindered by poor vascularization, prolonged inflammation, and excessive scar tissue formation, which necessitate newer strategies to simultaneously induce blood vessel regeneration, resolve inflammation, and induce host cell recruitment. Concurrent deployment of multiple biological cues to realize synergistic reparative effects may be an enticing avenue for wound healing. Herein, we simultaneously deployed SDF (stromal cell-derived factor)- 1α, VEGF (vascular endothelial growth factor)-binding peptide (BP), and GLP (glucagon like peptide)- 1 analog, liraglutide (LG) in core/shell poly(L-lactide-co-glycolide)/gelatin fibers to harness their synergistic effects for skin repair in healthy as well as diabetic wound models in rats. Microscopic techniques, such as SEM and TEM revealed fibrous and core/shell type morphology of membranes. Boyden chamber assay and scratch-wound assay displayed significant migration of HUVECs (human umbilical vein endothelial cells) in SDF-1α containing fibers. Subcutaneous implantation of membranes revealed higher cellular infiltration in SDF-1α loaded fibers, especially, those which were co-loaded with LG or BP. Implantation of membranes in an excisional wound model in healthy rats further showed significant and rapid wound closure in dual cues loaded groups as compared to control or single cue loaded groups. Similarly, the implantation of dressings in type 2 diabetes rat model revealed fast healing, skin appendages regeneration, and blood vessel regeneration in dual cues loaded fibers (SDF-1α/LG, SDF-1α/BP). Taken together, core/shell type fibers containing bioactive peptides significantly promoted wound repair in healthy as well as diabetic wound models in rats.

Dissolving microneedle-assisted long-acting Liraglutide delivery to control type 2 diabetes and obesity

Integrating nanoparticles (NPs) as a smart and targeted tool for drug delivery with dissolving microneedle (DMN) patch, the non-invasive device for drug delivery, is a promising for future therapeutic delivery applications. Liraglutide (Lira) encapsulation in poly (lactic-co-glycolic acid) (PLGA) NPs provides a sustained release of Lira to 15 days in a biphasic profile which 80% of released content happens in the first 8 days. Embedding such sustained release NPs in the DMN comprising poly vinyl pyrrolidone (PVP) 50% w/v, eliminates the need for Lira subcutaneous injection. Additionally, NPs containing DMN enhance mechanical strength of needles to 5.31 N compared to DMN with pure Lira content which was 4.32 N. The flexible backing layer of the DMN was obtained via blending of PVP and poly vinyl alcohol (PVA) in 10% w/v. Circular dichroism (CD) analysis showed that Lira encapsulated in NPs maintained its native secondary structure even after solidification in DMN. In this study, the capacity of 2 kinds of 500 μm and 1000 μm needles to deliver the desired dose of drug was obtained based on experimental and mathematical methods.

Particle engineering principles and technologies for pharmaceutical biologics

The global market of pharmaceutical biologics has expanded significantly during the last few decades. Currently, pharmaceutical biologic products constitute an indispensable part of the modern medicines. Most pharmaceutical biologic products are injections either in the forms of solutions or lyophilized powders because of their low oral bioavailability. There are certain pharmaceutical biologic entities formulated into particulate delivery systems for the administration via non-invasive routes or to achieve prolonged pharmaceutical actions to reduce the frequency of injections. It has been well documented that the design of nano- and microparticles via various particle engineering technologies could render pharmaceutical biologics with certain benefits including improved stability, enhanced intracellular uptake, prolonged pharmacological effect, enhanced bioavailability, reduced side effects, and improved patient compliance. Herein, we review the principles of the particle engineering technologies based on bottom-up approach and present the important formulation and process parameters that influence the critical quality attributes with some mathematical models. Subsequently, various nano- and microparticle engineering technologies used to formulate or process pharmaceutical biologic entities are reviewed. Lastly, an array of commercialized products of pharmaceutical biologics accomplished based on various particle engineering technologies are presented and the challenges in the development of particulate delivery systems for pharmaceutical biologics are discussed.

Polymeric microparticle systems for modified release of glucagon-like-peptide-1 receptor agonists

Type 2 diabetes is a fast-growing worldwide epidemic. Despite the multiple therapies available to treat type 2 diabetes, the disease is not correctly managed in over half of patients, mainly due to non-compliance with prescribed treatment regimes. The development of analogues to the glucagon-like peptide 1 (GLP-1) has resulted in the extension of its half-life and associated benefits. Further benefits in the use of peptide-based GLP-1 receptor agonists have been achieved by the use of controlled-release systems based on polymeric microparticles. In this review, we focus on commercially available formulations and others that remain in development, discussing the preparation methods and the relationship between in vitro and in vivo kinetic release behaviours.

Role of lipid nanocarriers for enhancing oral absorption and bioavailability of insulin and GLP-1 receptor agonists

Growing demand for insulin and glucagon-like peptide-1 receptor agonists (GLP-1 RA) is observed, considering the progressive nature of diabetes and the potential therapeutic role of peptides in its treatment. However, chronic parenteral administration is responsible for pain and rashes at the site of injection. Oral delivery of insulin and GLP-1 RA promises better patient compliance owing to their ease of administration and reduction in chances of peripheral hypoglycaemia and weight gain. The review article discusses the potential of lipid carriers in combination with different strategies such as absorption enhancers, PEGylation, lipidisation, etc. The lipid nanocarriers improve the membrane permeability and oral bioavailability of high molecular weight peptides. Additionally, the clinical status of different nanocarriers for anti-diabetic peptides is discussed. Previous research on nanocarriers showed significant hypoglycaemic activity and safety in animal studies; however, extrapolation of the same in human subjects is not validated. With the rising global burden of diabetes, the lipid nanocarriers show the potential to revolutionise treatment with oral delivery of insulin and GLP-1 RA.

Quality by design thinking in the development of long-acting injectable PLGA/PLA-based microspheres for peptide and protein drug delivery

Adopting the Quality by Design (QbD) approach in the drug development process has transformed from "nice-to-do" into a crucial and required part of the development, ensuring the quality of pharmaceutical products throughout their whole life cycles. This review is discussing the implementation of the QbD thinking into the production of long-acting injectable (LAI) PLGA/PLA-based microspheres for the therapeutic peptide and protein drug delivery. Various key elements of the QbD approaches are initially elaborated using Bydureon®, a commercial product of LAI PLGA/PLA-based microspheres, as a classical example. Subsequently, the factors influencing the release patterns and the stability of the peptide and protein drugs are discussed. This is followed by a summary of the state-of-the-art of manufacturing LAI PLGA/PLA-based microspheres and the related critical process parameters (CPPs). Finally, a landscape of generic product development of LAI PLGA/PLA-based microspheres is reviewed including some major challenges in the field.

Liraglutide regulates bone destruction and exhibits anti-inflammatory effects in periodontitis in vitro and in vivo

OBJECTIVES

This study investigated the effect of Liraglutide (LIRA) on osteogenic differentiation of human periodontal ligament cells (hPDLCs) stimulated by Porphyromonas gingivalis lipopolysaccharide (Pg-LPS) and its mechanismin in vitro. Further, investigated the osteoprotective and anti-inflammatory effects of LIRA in periodontitis in vivo.

MATERIALS AND METHODS

ALP staining, Alizarin red staining(AR-S), qRT-PCR, Western Blot, and immunofluorescence staining were used to elucidate the effect of LIRA on osteogenesis of hPDLCs. Western Blot was performed to evaluate the Wnt/β-catenin signaling-related protein. Moreover, male Wistar rats model of periodontitis were established to assess the anti-inflammatory and osteoprotective effect of LIRA in vivo.

RESULTS

After LIRA treatment, the formation of mineralized nodules was increased, the expression of ALP and Runx2 were upregulated. Moreover, Pg-LPS strongly activated the Wnt/β-catenin signaling pathway and reduced the osteogenesis of hPDLCs. But these effects were reversed by LIRA. The in vivo results showed that treatment with LIRA resulted in reduced inflammatory cell infiltration in periodontal tissues and decreased concentrations of TNF-α, IL-1β, and IL-6, and it reduced alveolar bone resorption.

CONCLUSIONS

Systemic administration of LIRA solution is a potential treatment for reducing inflammation and bone loss in periodontal disease. This suggests that LIRA can be used as a potential drug for the treatment of periodontitis.

CLINICAL SIGNIFICANCE

We showed that systemic administration of LIRA can have a beneficial effect in periodontitis. It can be used as a potential drug for the treatment of periodontitis.

Sustained release and pharmacologic evaluation of human glucagon-like peptide-1 and liraglutide from polymeric microparticles

The GLP1-receptor agonists exert regulatory key roles in diabetes, obesity and related complications. Here we aimed to develop polymeric microparticles loaded with homologous human GLP1 (7-37) or the analogue liraglutide. Peptide-loaded microparticles were prepared by a double emulsion and solvent evaporation process with a set of eight polymers based on lactide (PLA) or lactide-glycolide (PLGA), and evaluated for particle-size distribution, morphology, in vitro release and pharmacologic activity in mice. The resulting microparticles showed size distribution of about 30-50 μm. The in vitro kinetic release assays showed a sustained release of the peptides extending up to 30-40 days. In vivo evaluation in Swiss male mice revealed a similar extension of glycemic and body weight gain modulation for up to 25 days after a single subcutaneous administration of either hGLP1-microparticles or liraglutide-microparticles. Microparticles-loaded hGLP1 shows equivalent in vivo pharmacologic activity to the microparticles-loaded liraglutide.

Platelet-membrane-biomimetic nanoparticles for targeted antitumor drug delivery

BACKGROUND

Nanoscale drug-delivery systems (DDSs) have great promise in tumor diagnosis and treatment. Platelet membrane (PLTM) biomimetic DDSs are expected to enhance retention in vivo and escape uptake by macrophages, as well as minimizing immunogenicity, attributing to the CD47 protein in PLTM sends "don't eat me" signals to macrophages. In addition, P-selectin is overexpressed on the PLTM, which would allow a PLTM-biomimetic DDS to specifically bind to the CD44 receptors upregulated on the surface of cancer cells.

RESULTS

In this study, porous nanoparticles loaded with the anti-cancer drug bufalin (Bu) were prepared from a chitosan oligosaccharide (CS)-poly(lactic-co-glycolic acid) (PLGA) copolymer. These were subsequently coated with platelet membrane (PLTM) to form PLTM-CS-pPLGA/Bu NPs. The PLTM-CS-pPLGA/Bu NPs bear a particle size of ~ 192 nm, and present the same surface proteins as the PLTM. Confocal microscopy and flow cytometry results revealed a greater uptake of PLTM-CS-pPLGA/Bu NPs than uncoated CS-pPLGA/Bu NPs, as a result of the targeted binding of P-selectin on the surface of the PLTM to the CD44 receptors of H22 hepatoma cells. In vivo biodistribution studies in H22-tumor carrying mice revealed that the PLTM-CS-pPLGA NPs accumulated in the tumor, because of a combination of active targeting effect and the EPR effect. The PLTM-CS-pPLGA/Bu NPs led to more effective tumor growth inhibition over other bufalin formulations.

CONCLUSIONS

Platelet membrane biomimetic nanoparticles played a promising targeted treatment of cancer with low side effect.

Poly(lactic-co-glycolic acid) devices: Production and applications for sustained protein delivery

Injectable or implantable poly(lactic-co-glycolic acid) (PLGA) devices for the sustained delivery of proteins have been widely studied and utilized to overcome the necessity of repeated administrations for therapeutic proteins due to poor pharmacokinetic profiles of macromolecular therapies. These devices can come in the form of microparticles, implants, or patches depending on the disease state and route of administration. Furthermore, the release rate can be tuned from weeks to months by controlling the polymer composition, geometry of the device, or introducing additives during device fabrication. Slow-release devices have become a very powerful tool for modern medicine. Production of these devices has initially focused on emulsion-based methods, relying on phase separation to encapsulate proteins within polymeric microparticles. Process parameters and the effect of additives have been thoroughly researched to ensure protein stability during device manufacturing and to control the release profile. Continuous fluidic production methods have also been utilized to create protein-laden PLGA devices through spray drying and electrospray production. Thermal processing of PLGA with solid proteins is an emerging production method that allows for continuous, high-throughput manufacturing of PLGA/protein devices. Overall, polymeric materials for protein delivery remain an emerging field of research for the creation of single administration treatments for a wide variety of disease. This review describes, in detail, methods to make PLGA devices, comparing traditional emulsion-based methods to emerging methods to fabricate protein-laden devices. This article is categorized under: Biology-Inspired Nanomaterials > Protein and Virus-Based Structures Implantable Materials and Surgical Technologies > Nanomaterials and Implants Biology-Inspired Nanomaterials > Peptide-Based Structures.

Long-Acting Release Microspheres Containing Novel GLP-1 Analog as an Antidiabetic System

Glucagon-like peptide 1 (GLP-1) has recently received significant attention as an efficacious way to treat diabetes mellitus. However, the short half-life of the peptide limits its clinical application in diabetes. In our previous study, a novel GLP-1 analog (PGLP-1) with a longer half-life was synthesized and evaluated. Herein, we prepared the PGLP-1-loaded poly(d,l-lactide- co-glycolide) microspheres to achieve long-term effects on blood glucose control. The incorporation of zinc ion into the formulation can effectively decrease the initial burst release, and a uniform drug distribution was obtained, in contrast to native PGLP-1 encapsulated microspheres. We demonstrated that the solubility of the drug encapsulated in microspheres played an important role in in vitro release behavior and drug distribution inside the microspheres. The Zn-PGLP-1 microspheres had a prominent acute glucose reduction effect in the healthy mice. A hypoglycemic effect was observed in the streptozotocin (STZ) induced diabetic mice through a 6-week treatment of Zn-PGLP-1-loaded microspheres. Meanwhile, the administration of Zn-PGLP-1 microspheres led to the β-cell protection and stimulation of insulin secretion. The novel GLP-1 analog-loaded sustained microspheres may greatly improve patient compliance along with a desirable safety feature.

Insulin-loaded PLGA microspheres for glucose-responsive release

Porous poly(lactic-co-glycolic acid) (PLGA) microspheres were prepared, loaded with insulin, and then coated in poly(vinyl alcohol) (PVA) and a novel boronic acid-containing copolymer [poly(acrylamide phenyl boronic acid-co-N-vinylcaprolactam); p(AAPBA-co-NVCL)]. Multilayer microspheres were generated using a layer-by-layer approach depositing alternating coats of PVA and p(AAPBA-co-NVCL) on the PLGA surface, with the optimal system found to be that with eight alternating layers of each coating. The resultant material comprised spherical particles with a porous PLGA core and the pores covered in the coating layers. Insulin could successfully be loaded into the particles, with loading capacity and encapsulation efficiencies reaching 2.83 ± 0.15 and 82.6 ± 5.1% respectively, and was found to be present in the amorphous form. The insulin-loaded microspheres could regulate drug release in response to a changing concentration of glucose. In vitro and in vivo toxicology tests demonstrated that they are safe and have high biocompatibility. Using the multilayer microspheres to treat diabetic mice, we found they can effectively control blood sugar levels over at least 18 days, retaining their glucose-sensitive properties during this time. Therefore, the novel multilayer microspheres developed in this work have significant potential as smart drug-delivery systems for the treatment of diabetes.

Spatiotemporal delivery of nanoformulated liraglutide for cardiac regeneration after myocardial infarction

The local, intramyocardial injection of proteins into the infarcted heart is an attractive option to initiate cardiac regeneration after myocardial infarction (MI). Liraglutide, which was developed as a treatment for type 2 diabetes, has been implicated as one of the most promising protein candidates in cardiac regeneration. A significant challenge to the therapeutic use of this protein is its short half-life in vivo. In this study, we evaluated the therapeutic effects and long-term retention of liraglutide loaded in poly(lactic-co-glycolic acid)-poly(ethylene glycol) (PLGA-PEG) nanoparticles (NP-liraglutide) on experimental MI. PLGA-PEG nanoparticles (NPs) have been shown to efficiently load liraglutide and release bioactive liraglutide in a sustained manner. For in vitro test, the released liraglutide retained bioactivity, as measured by its ability to activate liraglutide signaling pathways. Next, we compared the effects of an intramyocardial injection of saline, empty NPs, free liraglutide and NP-liraglutide in a rat model of MI. NPs were detected in the myocardium for up to 4 weeks. More importantly, an intramyocardial injection of NP-liraglutide was sufficient to improve cardiac function (P<0.05), attenuate the infarct size (P<0.05), preserve wall thickness (P<0.05), promote angiogenesis (P<0.05) and prevent cardiomyocyte apoptosis (P<0.05) at 4 weeks after injection without affecting glucose levels. The local, controlled, intramyocardial delivery of NP-liraglutide represents an effective and promising strategy for the treatment of MI.

Phenylboronic acid-diol crosslinked 6-O-vinylazeloyl-d-galactose nanocarriers for insulin delivery

A new block polymer named poly 3-acrylamidophenylboronic acid-b-6-O-vinylazeloyl-d-galactose (p(AAPBA-b-OVZG)) was prepared using 3-acrylamidophenylboronic acid (AAPBA) and 6-O-vinylazeloyl-d-galactose (OVZG) via a two-step procedure involving S-1-dodecyl-S-(α', α'-dimethyl-α″-acetic acid) trithiocarbonate (DDATC) as chain transfer agent, 2,2-azobisisobutyronitrile (AIBN) as initiator and dimethyl formamide (DMF) as solvent. The structures of the polymer were examined by Fourier transform infrared spectroscopy (FT-IR) and ¹H NMR and the thermal stability was determined by thermal gravimetric analysis (TG/DTG). Transmission electron microscopy (TEM) and dynamic light scattering (DLS) were utilized to evaluate the morphology and properties of the p(AAPBA-b-OVZG) nanoparticles. The cell toxicity, animal toxicity and therapeutic efficacy were also investigated. The results indicate the p(AAPBA-b-OVZG) was successfully synthesized and had excellent thermal stability. Moreover, the p(AAPBA-b-OVZG) nanoparticles were submicron in size and glucose-sensitive in phosphate-buffered saline (PBS). In addition, insulin as a model drug had a high encapsulation efficiency and loading capacity and the release of insulin was increased at higher glucose levels. Furthermore, the nanoparticles showed a low-toxicity in cell and animal studies and they were effective at decreasing blood glucose levels of mice over 96h. These p(AAPBA-b-OVZG) nanoparticles show promise for applications in diabetes treatment using insulin or other hypoglycemic proteins.