In Situ Bio-Artificial Endocrine Pancreas (BEP) Platform: Subcutaneous Immuno-Isolation Architecture for Post-Pancreatectomy Metabolic Rescue

In Situ Bio-Artificial Endocrine Pancreas (BEP) Platform: Subcutaneous Immuno-Isolation Architecture for Post-Pancreatectomy Metabolic Rescue Description / Abstract: Total pancreatectomy secondary to aggressive pancreatic ductal adenocarcinoma (PDAC) or severe chronic pancreatitis induces brittle surgical diabetes. Conventional allotransplantation is fundamentally contraindicated in oncological cohorts due to mandatory systemic immunosuppression, which promotes malignant metastasis. This technical document discloses the structural, biophysical, and fluidic framework of an implantable, bio-hybrid endocrine device designed for subcutaneous or pre-peritoneal deployment. The platform establishes an unbreachable physical immuno-isolation boundary while maintaining physiological small-molecule transport kinetics: Dual-Scale Biocompatible Housing: Human clinical-scale (45.0\text{ mm} \times 8.0\text{ mm}) and pre-clinical rodent-scale (14.0\text{ mm} \times 3.2\text{ mm}) rigid Grade 5 ELI Titanium / PEEK chassis with continuous filleted radii to prevent high mechanical stress concentrations and foreign body reaction (FBR). Calibrated Immuno-Isolation: 30–50\text{ nm} nominal pore size (MWCO: 50–100\text{ kDa}) exclusion boundary blocking lökosit infiltration, T/B-cell contact, and immunoglobulin G (IgG, \sim 150\text{ kDa}), while allowing passive convective-diffusive transport of glucose, oxygen, and insulin. Surface Hydration & Angiogenesis: Surface-modified zwitterionic Poly-SBMA brush layer providing a non-fouling hydration shield against non-specific protein adsorption, integrated with a controlled-release abluminal pro-angiogenic nano-coating (VEGF-A / bFGF). TPMS Gyroid Cellular Core: Triply Periodic Minimal Surface (TPMS) micro-porous scaffold maintaining a maximum cellular-to-membrane diffusion distance of \le 100\ \mu\text{m}, achieving a physiological first-phase insulin kinetic latency of \le 12.0\text{ minutes} (11.4\text{ min} simulated). Minimally Invasive Interlocking Cartridge: Laparoscopic bayonet/snap-fit mechanism decoupling the cellular payload from the permanently vascularized external housing for outpatient maintenance. LEGAL & COMMERCIAL RESTRICTION NOTICE Copyright © 2026 Oğuzhan Yumak. All Rights Reserved. This publication serves exclusively as an authoritative Prior Art technical disclosure under academic and prior invention documentation standards. Commercial exploitation, unauthorized industrial reproduction, manufacturing, clinical application, or incorporation into proprietary commercial IP filings without an executed written Commercial Licensing Agreement with the author is strictly prohibited. For technical licensing, sponsored research, or partnership inquiries, contact the author directly.