Engineered nanoparticles in non-invasive insulin delivery for precision therapeutics of diabetes

Diabetes mellitus is a chronic disease leading to the death of millions a year across the world. Insulin is required for Type 1, Type 2, and gestational diabetic patients, however, there are various modes of insulin delivery out of which oral delivery is noninvasive and convenient. Moreover, factors like insulin degradation and poor intestinal absorption play a crucial role in its bioavailability and effectiveness. This review discusses various types of engineered nanoparticles used in-vitro, in-vivo, and ex-vivo insulin delivery along with their administration routes and physicochemical properties. Injectable insulin formulations, currently in use have certain limitations, leading to invasiveness, low patient compliance, causing inflammation, and side effects. Based on these drawbacks, this review emphasizes more on the non-invasive route, particularly oral delivery. The article is important because it focuses on how engineered nanoparticles can overcome the limitations of free therapeutics (drugs alone), navigate the barriers, and accomplish precision therapeutics in diabetes. In future, more drugs could be delivered with a similar strategy to cure various diseases and resolve challenges in drug delivery. This review significantly describes the role of various engineered nanoparticles in improving the bioavailability of insulin by protecting it from various barriers during non-invasive routes of delivery.

A step towards glucose control with a novel nanomagnetic-insulin for diabetes care

Massive efforts have been devoted to insulin delivery for diabetes care. Achieving a long-term tight-regulated blood glucose level with a low risk of hypoglycemia remains a great challenge. In this study we propose a novel strategy to efficiently regulate insulin action after insulin is injected or released into patient body aiming to achieve better glycemic control, which is achieved by the administration of insulin-conjugated magnetic nanoparticles (MNPs-Ins). We show that the locomotion of MNPs-Ins can be controlled to reach a target site on an in vitro microfluidic platform, which may open a way to modulate the physiological effect of insulin in a remote-control manner. Most importantly, the in vivo blood glucose regulation of the MNPs-Ins was performed on diabetic mice to understand the glycemic control performance. The results showed that the MNPs-Ins can achieve a better glycemic control with longer effective drug duration while not causing hypoglycemia and a magnetic-modulated hypoglycemic dynamics. Moreover, the in vivo histochemistry experiments confirmed the good biocompatibility of MNPs-Ins. Along with our on-going research on the possibility of the recycle and reuse of the MNPs-Ins, the finding presented in this paper may manifest a fascinating potential in insulin delivery in the near future.

Functionalized graphene oxide as a vehicle for targeted drug delivery and bioimaging applications

Graphene oxide (GO) has attracted tremendous attention as a most promising nanomaterial among the carbon family since it emerged as a polynomial functional tool with rational applications in diverse fields such as biomedical engineering, electrocatalysis, biosensing, energy conversion, and storage devices. Despite having certain limitations due to its irreversible aggregation performance owing largely to the strong van der Waals interactions, efforts have been made to smartly engineer its surface chemistry for realistic multimodal applications. The use of such GO-based engineered devices has increased rapidly in the last few years, principally due to its excellent properties, such as huge surface area, honeycomb-like structure allowing vacant interstitial space to accommodate compounds, sp2 hybridized carbon, improved biocompatibility and cell surface penetration due to electronic interactions. Amongst multifaceted GO dynamics, in this review, attempts are made to discuss the advanced applications of GO or graphene-based materials (GBNs) in the biomedical field involving drug or therapeutic gene delivery, dual drug or drug-gene combination targeting, special delivery of drug cocktails to the brain, stimuli-responsive release of molecular payloads, and Janus-structured smart applications for polar-nonpolar combination drug loading followed by targeting together with smart bioimaging approaches. In addition, the advantages of duel-drug delivery systems are discussed in detail. We also discuss various electronic mechanisms, and detailed surface engineering to meet microcosmic criteria for its utilization, various novel implementations of engineered GO as mentioned above, together with discussions of its inevitable toxicity or disadvantages. We hope that the target audience, belonging to biomedical engineering, pharmaceutical or material science fields, may acquire relevant information from this review which may help them design future studies in this field.

Can nanoparticles and nano‒protein interactions bring a bright future for insulin delivery?

Insulin therapy plays an essential role in the treatment of diabetes mellitus. However, frequent injections required to effectively control the glycemic levels lead to substantial inconvenience and low patient compliance. In order to improve insulin delivery, many efforts have been made, such as developing the nanoparticles (NPs)-based release systems and oral insulin. Although some improvements have been achieved, the ultimate results are still unsatisfying and none of insulin-loaded NPs systems have been approved for clinical use so far. Recently, nano‒protein interactions and protein corona formation have drawn much attention due to their negative influence on the in vivo fate of NPs systems. As the other side of a coin, such interactions can also be used for constructing advanced drug delivery systems. Herein, we aim to provide an insight into the advance and flaws of various NPs-based insulin delivery systems. Particularly, an interesting discussion on nano‒protein interactions and its potentials for developing novel insulin delivery systems is initiated.

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Insulin therapy plays essential roles in treating diabetes.

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Optimizing insulin delivery enhances insulin therapy.

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Nanoparticles are promising systems for delivery of insulin.

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Nano-protein interactions influence the delivery of nanoparticles.

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Nano-protein interactions can be used for advanced delivery of insulin.

Effect of the concentration of protein and nanoparticles on the structure of biohybrid nanocomposites

We present colloidal nanocomposites formed by incorporating magnetite Fe₃ O₄ nanoparticles (MNPs) with lysozyme amyloid fibrils (LAFs). Preparation of two types of solutions, with and without addition of salt, was carried out to elucidate the structure of MNPs-incorporated fibrillary nanocomposites and to study the effect of the presence of salt on the stability of the nanocomposites. The structural morphology of the LAFs and their interaction with MNPs were analyzed by atomic force microscopy and small-angle x-ray scattering measurements. The results indicate that conformational properties of the fibrils are dependent on the concentration of protein, and the precise ratio of the concentration of the protein and MNPs is crucially important for the stability of the fibrillary nanocomposites. Our results confirm that despite the change in fibrillary morphology induced by the varying concentration of the protein, the adsorption of MNPs on the surface of LAF is morphologically independent. Moreover, most importantly, the samples containing salt have excellent stability for up to 1 year of shelf-life.

Exploring Light-Sensitive Nanocarriers for Simultaneous Triggered Antibiotic Release and Disruption of Biofilms Upon Generation of Laser-Induced Vapor Nanobubbles

Impaired penetration of antibiotics through bacterial biofilms is one of the reasons for failure of antimicrobial therapy. Hindered drug diffusion is caused on the one hand by interactions with the sticky biofilm matrix and on the other hand by the fact that bacterial cells are organized in densely packed clusters of cells. Binding interactions with the biofilm matrix can be avoided by encapsulating the antibiotics into nanocarriers, while interfering with the integrity of the dense cell clusters can enhance drug transport deep into the biofilm. Vapor nanobubbles (VNB), generated from laser irradiated nanoparticles, are a recently reported effective way to loosen up the biofilm structure in order to enhance drug transport and efficacy. In the present study, we explored if the disruptive force of VNB can be used simultaneously to interfere with the biofilm structure and trigger antibiotic release from light-responsive nanocarriers. The antibiotic tobramycin was incorporated in two types of light-responsive nanocarriers-liposomes functionalized with gold nanoparticles (Lip-AuNP) and graphene quantum dots (GQD)-and their efficacy was evaluated on Pseudomonas aeruginosa biofilms. Even though the anti-biofilm efficacy of tobramycin was improved by liposomal encapsulation, electrostatic functionalization with 70 nm AuNP unfortunately resulted in premature leakage of tobramycin in a matter of hours. Laser-irradiation consequently did not further improve P. aeruginosa biofilm eradication. Adsorption of tobramycin to GQD, on the other hand, did result in a stable formulation with high encapsulation efficiency, without burst release of tobramycin from the nanocarriers. However, even though laser-induced VNB formation from GQD resulted in biofilm disruption, an enhanced anti-biofilm effect was not achieved due to tobramycin not being efficiently released from GQD. Even though this study was unsuccessful in designing suitable nanocarriers for simultaneous biofilm disruption and light-triggered release of tobramycin, it provides insights into the difficulties and challenges that need to be considered for future developments in this regard.

Analysis of the influence of synthetic paramaters on the structure and physico-chemical properties of non-spherical iron oxide nanocrystals and their biological stability and compatibility

Monodisperse non-spherical magnetic IONCs obtained by simple methods display excellent magnetic properties with high potential for theranostic applications.

Carbon nanomaterials combined with metal nanoparticles for theranostic applications

Among targeted delivery systems, platforms with nanosize dimensions, such as carbon nanomaterials (CNMs) and metal nanoparticles (NPs), have shown great potential in biomedical applications. They have received considerable interest in recent years, especially with respect to their potential utilization in the field of cancer diagnosis and therapy. The many functions of nanomaterials provide opportunities to use them as multimodal agents for theranostics, a combination of therapy and diagnosis. Carbon nanotubes and graphene are some of the most widely used CNMs because of their unique structural and physicochemical properties. Their high specific surface area allows for efficient drug loading and the possibility of functionalization with various bioactive molecules. In addition, CNMs are ideal platforms for the attachment of NPs. In the biomedical field, NPs have also shown tremendous potential for use in drug delivery, non-invasive tumour imaging and early detection due to their optical and magnetic properties. NP/CNM hybrids not only combine the unique properties of the NPs and CNMs but they also exhibit new properties arising from interactions between the two entities. In this review, the preparation of CNMs conjugated to different types of metal NPs and their applications in diagnosis, imaging, therapy and theranostics are presented.

Electrochemically triggered release of human insulin from an insulin-impregnated reduced graphene oxide modified electrode

An electrochemical insulin-delivery system based on reduced graphene oxide impregnated with insulin is described.

A novel template free synthetic strategy to graphene–iron oxide nanotube hybrid

A magnetically separable graphene–iron oxide nanotube composite was synthesised for the first time via an adept template free hydrothermal route.

Graphene oxide incorporated collagen–fibrin biofilm as a wound dressing material

GO was incorporated in the collagen and fibrin composite film (CFGO), these films were used as wound dressing material on the experimental wounds of rats and the efficacy of CFGO was studied using conventional methods (schematic illustration).