Abstract

Diabetes mellitus is also one of the most pressing health problems in the world today, with both type 1 and type 2 diabetes increasing morbidity and other chronic complications. Although insulin therapy is lifesaving, existing delivery methods, including multiple daily injections, insulin pens, etc., have limitations in terms of invasiveness, poor adherence, and poor glycaemic control. Such restrictions have necessitated rapid innovation in insulin-delivery technologies to enhance physiological mimicry and improve care for people. The current mini-review summarizes insulin delivery system development, focusing on the evolution from the earliest injection-based devices to modern Automatic Insulin Delivery (AID) and hybrid closed-loop platforms. Most recent trends in control systems based on algorithms, wearable and patch-capable devices, glucose-responsive (innovative) insulin formulations, and alternative non-invasive delivery methods, such as oral, transdermal, and inhalable medications, are critically addressed. Special focus is being made on carriers enabled by nanotechnology, biocompatible materials, and integrated biosensors, which make it stable, responsive, and capable of sustained insulin release. Existing clinical evidence, regulatory do-not-resuscitate orders, and practical issues related to safety, usability, cost, and fair access are also discussed. Lastly, the novel trends combining AI, individualized dosing plans, and intelligent biomaterials are highlighted as the most effective forces shaping the future of insulin treatment. Today, these developments indicate a shift toward safer, more reliable, and patient-friendly insulin delivery systems that could change the way diabetes is managed..

Keywords:Insulin delivery systems; Automated insulin delivery; Glucose-responsive insulin; Nanotechnology; Microneedle-based delivery; Diabetes mellitus

Abbreviations: HCL: Hybrid Closed-Loop; MDI: Multiple Daily Injections; CSII: Continuous Subcutaneous Insulin Infusion; AID: Automated Insulin Delivery; Gox: Glucose Oxidase; MN: Microneedle; CGM: Continuous Glucose Monitoring; T2D: Type 2 Diabetes; T1D: Type 1 Diabetes; HbA1c: Glycated Hemoglobin; PBA: Phenylboronic Acid; SLNs: Solid Lipid Nanoparticles; NLCs: Nanostructured Lipid Carriers; NPs: Nanoparticles; GI: Gastrointestinal; PNPs: Polymeric Nanoparticles