Development and Characterization of a Polyherbal Formulation with Copper Nanoparticles (Tamra Bhasma)

Abstract

For millennia, herbal medicines have remained a cornerstone of global healthcare, widely recognized for their safety, tolerability, and efficacy in managing chronic diseases. With the global burden of diabetes escalating from 200 million cases in 1990 to 589 million adults in 2024—and projected to reach 853 million by 2050 (WHO, 2024; IDF, 2025)—the limitations of conventional synthetic hypoglycemic agents have intensified interest in plant-derived multi-target therapies. Polyherbal formulations (PHFs) have emerged as a promising strategy to exploit synergistic bioactive interactions for improved therapeutic outcomes. In this study, a novel PHF from Stevia rebaudiana, Cinnamomum zeylanicum, Trigonella foenum-graecum, and Hibiscus rosa-sinensis was prepared and blended with incinerated copper nanoparticles (Tamra bhasma) through traditional bhasmikarana calcination. The formulation was rigorously evaluated for physicochemical properties and characterized using GC-MS, FTIR, HPTLC, and SEM. Total phenolic content (TPC) ranged from 9.5 to 59.5 mg QE/g extract (R² = 0.9964), confirming a strong linear dose–response relationship. GC-MS analysis identified 19 bioactive compounds including (E)-cinnamaldehyde (RT: 11.26 min), trans-cinnamic acid (RT: 13.43 min), pyrocatechol, and linoleic acid with established antidiabetic and antioxidant activity. FTIR confirmed the presence of hydroxyl (3349.26 cm⁻¹), carbonyl (1642.99 cm⁻¹), and Cu–O stretching (896.17–864.48 cm⁻¹) functional groups. HPTLC fingerprinting at 254 nm and 366 nm revealed well-resolved bands corresponding to quercetin, cinnamic acid, stevioside, and cinnamaldehyde. SEM analysis demonstrated distinctive spongy microcrystalline aggregates (8–10 μm) in Tamra bhasma versus compact plate-like particles (~1 μm) in standard CuO, confirming structural transformation during calcination. UV-visible spectroscopy showed characteristic absorption bands at 340 nm and 460 nm, consistent with cupric oxide nanoparticles. All classical Ayurvedic quality tests (Varitaratva, Rekhapurnata, Nishchandrata, and Dadhi Pariksha) were satisfied. The findings confirm the successful development of a phytochemical-rich, analytically standardized formulation with copper nanoparticle integration, suggesting strong potential as a novel complementary therapeutic approach for type 2 diabetes mellitus.