Browsing by Author "Basu, B."

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Effect of Fe3+ substitution on the structural modification and band structure modulated UV absorption of hydroxyapatite
(Blackwell Publishing Ltd, 2021) Hadagalli, K.; Shenoy, S.; Shakya, K.R.; Manjunath, G.; Tarafder, K.; Mandal, S.; Basu, B.
The effect of Fe3+ ionic substitution in hydroxyapatite (Ca10-xFex(PO4)6(OH)2) was studied using structural modifications, resulting in an improvement in UV absorption through a tailored optical band structure. Ca2+ of HA being larger compared to Fe3+ contributes to the shrinkage of the lattice. Undoped HA has a peak at 1085 cm?1 (?3 PO43?) which is shifted to 1033 cm?1 for Fe-HA, because of the perturbation in HA structure. An improvement of UV absorption in the entire UVA and UVB range with an increase in Fe content because of a decrease in bandgap from 5.9 eV to 2.1 eV with undoped and doped HA. Theoretically obtained band gap and optical behaviour of the systems are well correlated with the experimental findings. Moreover, the use of marine biowaste from cuttlefish bone, as the source of HA; low cost and promising UV absorption can have a potential application as UV protective sunscreen filters. © 2020 The American Ceramic Society
Evaluation of implant properties, safety profile and clinical efficacy of patient-specific acrylic prosthesis in cranioplasty using 3D binderjet printed cranium model: A pilot study
(Churchill Livingstone, 2021) Basu, B.; Bhaskar, N.; Barui, S.; Sharma, V.; Das, S.; Govindarajan, N.; Hegde, P.; Perikal, P.J.; Antharasanahalli Shivakumar, M.; Khanapure, K.; Jagannatha, A.
There exists a significant demand to develop patient-specific prosthesis in reconstruction of cranial vaults after decompressive craniectomy. we report here, the outcomes of an unicentric pilot study on acrylic cranial prosthesis fabricated using a 3D printed cranium model with its clinically relevant mechanical properties. Methods: The semi-crystalline polymethyl methacrylate (PMMA) implants, shaped to the cranial defects of 3D printed cranium model, were implanted in 10 patients (mean age, 40.8 ± 14.8 years). A binderjet 3D printer was used to create patient-specific mould and PMMA was casted to fabricate prosthesis which was analyzed for microstructure and properties. Patients were followed up for allergy, infection and cosmesis for a period of 6 months. Results: As-cast PMMA flap exhibited hardness of 15.8 ± 0.24Hv, tensile strength of 30.7 ± 3.9 MPa and elastic modulus of 1.5 ± 0.1 GPa. 3D microstructure of the semi-crystalline acrylic implant revealed 2.5–15 µm spherical isolated pores. The mean area of the calvarial defect in craniectomy patients was 94.7 ± 17.4 cm2. We achieved a cranial index of symmetry (CIS -%) of 94.5 ± 3.9, while the average post-operative Glasgow outcome scale (GOS) score recorded was 4.2 ± 0.9. Conclusions: 3D printing based patient-specific design and fabrication of acrylic cranioplasty implant is safe and achieves acceptable cosmetic and clinical outcomes in patients with decompressive craniectomy. Our study ensured clinically acceptable structural and mechanical properties of implanted PMMA, suggesting that a low cost 3D printer based PMMA flap is an affordable option for cranioplasty in resource constrained settings. © 2021 Elsevier Ltd
Faster Biomineralization and Tailored Mechanical Properties of Marine-Resource-Derived Hydroxyapatite Scaffolds with Tunable Interconnected Porous Architecture
(2019) Hadagalli, K.; Panda, A.K.; Mandal, S.; Basu, B.
Although hydroxyapatite (HA)-based porous scaffolds have been widely researched in the last three decades, the development of naturally derived biomimetic HA with a tunable elastic modulus and strength together with faster biomineralization properties has not yet been achieved. To address this specific issue, we report here a scalable biogenic synthesis approach to obtain submicron HA powders from cuttlefish bone. The marine-resource-derived HA together with different pore formers can be conventionally sintered to produce physiologically relevant scaffolds with porous architecture. Depending on pore formers, the scaffolds with a range of porosity of up to 51% with a larger range of pore sizes up to 50 ?m were fabricated. An empirical relationship between the compression strength and the elastic modulus with fractional porosity was established. A combination of moderate compressive strength (12-15 MPa) with an elastic modulus up to 1.6 GPa was obtained from cuttlefish-bone-derived HA with wheat flour as the pore former. Most importantly, the specific HA scaffold supports the faster nucleation and growth of the biomineralized apatite layer with full coverage within 3 days of incubation in simulated body fluid. More importantly, the marine-species-derived HA supported better adhesion and proliferation of murine osteoblast cells than HA sintered using powders from nonbiogenic resources. The spectrum of physical and biomineralization properties makes cuttlefish-bone-derived porous HA a new generation of implantable biomaterial for potential application in cancellous bone regeneration. 2019 American Chemical Society.
Faster Biomineralization and Tailored Mechanical Properties of Marine-Resource-Derived Hydroxyapatite Scaffolds with Tunable Interconnected Porous Architecture
(American Chemical Society service@acs.org, 2019) Hadagalli, K.; Panda, A.K.; Mandal, S.; Basu, B.
Although hydroxyapatite (HA)-based porous scaffolds have been widely researched in the last three decades, the development of naturally derived biomimetic HA with a tunable elastic modulus and strength together with faster biomineralization properties has not yet been achieved. To address this specific issue, we report here a scalable biogenic synthesis approach to obtain submicron HA powders from cuttlefish bone. The marine-resource-derived HA together with different pore formers can be conventionally sintered to produce physiologically relevant scaffolds with porous architecture. Depending on pore formers, the scaffolds with a range of porosity of up to 51% with a larger range of pore sizes up to 50 ?m were fabricated. An empirical relationship between the compression strength and the elastic modulus with fractional porosity was established. A combination of moderate compressive strength (12-15 MPa) with an elastic modulus up to 1.6 GPa was obtained from cuttlefish-bone-derived HA with wheat flour as the pore former. Most importantly, the specific HA scaffold supports the faster nucleation and growth of the biomineralized apatite layer with full coverage within 3 days of incubation in simulated body fluid. More importantly, the marine-species-derived HA supported better adhesion and proliferation of murine osteoblast cells than HA sintered using powders from nonbiogenic resources. The spectrum of physical and biomineralization properties makes cuttlefish-bone-derived porous HA a new generation of implantable biomaterial for potential application in cancellous bone regeneration. © 2019 American Chemical Society.
Structural, compositional and spectral investigation of prawn exoskeleton nanocomposite: UV protection from mycosporine-like amino acids
(Elsevier Ltd, 2020) Hadagalli, K.; Kumar, R.; Mandal, S.; Basu, B.
The present work explores the use of marine resourced prawn exoskeleton/shell as a new class of naturally occurring composite containing UV absorbing proteins. Mycosporine-like amino acids with a central aromatic ring in the exoskeleton/shell of naturally occurring prawns (Fenneropenaeus Indicus) offer excellent UV protection. The architecture of shell composite constitutes a matrix of chitin-proteins with distinct reinforcements such as spherical calcites (CaCO3), microscopic proteins, and traces of hydroxides/oxides of magnesium. The presence of tryptophan, phenylalanine, and tyrosine, forming the basic building blocks of mycosporines, is confirmed by structural, compositional, and microscopic studies on prawn shells. The UV spectroscopic signatures at 290 and 320 nm provides strong evidence for the highest UV absorption. UV absorption attributes to the presence of mycosporine-like amino acids. Hence, the current exploration of naturally occurring prawn shells directs towards an additive-free sunscreen filter without the generation of detrimental free radicals. © 2020 Elsevier B.V.