A comprehensive investigation of the Sr3AsX3 (X = F/Cl/Br) inorganic cubic perovskites' strain-induced structural, electronic, optical, and mechanical properties with solar cell applications.

In comparison to the lead halide perovskites, nowadays, lead-free halide perovskites have demonstrated a number of benefits, including efficient optical absorption, increased stability, variable bandgap, excellent mobility of carriers, non-toxicity, abundant raw ingredients, and low manufacturing cost. The use of the Perdew-Burke-Ernzerhof (PBE) and Heyd-Scuseria-Ernzerhof (HSE) hybrid functional inside the quantum espresso software allowed for a thorough examination of these materials, potentially leading to improvements in the development of ecologically acceptable and economically sustainable perovskite-based products. This work has extensively examined the effects of compressive and tensile strain on the structural, optical, and electronic characteristics of the inorganic cubic perovskite Sr3AsX3 (X = F, Cl, Br) with varying X anion using first-principles density-functional theory (FP-DFT). At the Γ point, the unstrained Sr3AsF3, Sr3AsCl3, and Sr3AsBr3 compounds have a direct bandgap of 1.68/2.50 eV, 1.65/2.47 eV, and 1.522/2.30 eV, respectively, from the PBE/HSE methods. A drop in bandgap values occurs when the X-anion switches from F to Cl to Br. Furthermore, the bandgaps of the three proposed structures show a minor increase in response to tensile strain and a decreasing prevalence in response to compressive strain. The optical properties, which include dielectric functions, absorption coefficient, and electron loss function, are consistent with the band characteristics of these components, all of which point to a significant capability for absorption in the visible region. The dielectric constants of Sr3AsF3, Sr3AsCl3, and Sr3AsBr3 are discovered to have peaks that, with compressive strain, redshift (move towards lower photon energy) and, under tensile strain, blueshift (move towards upper photon energy). In comparison to the compounds Sr3AsF3 and Sr3AsCl3, the parameters indicate that the material Sr3AsBr3 is more optically advantageous. The SCAPS-1D simulator was used to methodically examine the photovoltaic (PV) performance of novel cell topologies that included SnS2 as an electron transport layer (ETL) and Sr3AsF3, Sr3AsCl3, and Sr3AsBr3 as absorbers and primarily 19.76, 19.89, and 20.89% PCE was achieved, respectively.

Expression of concern: A well-defined S-g-C3N4/Cu-NiS heterojunction interface towards enhanced spatial charge separation with excellent photocatalytic ability: synergetic effect, kinetics, antibacterial activity, and mechanism insights.

Expression of concern for 'A well-defined S-g-C3N4/Cu-NiS heterojunction interface towards enhanced spatial charge separation with excellent photocatalytic ability: synergetic effect, kinetics, antibacterial activity, and mechanism insights' by Haya A. Abubshait et al., RSC Adv., 2022, 12, 3274-3286, https://doi.org/10.1039/D1RA07974C.

Expression of concern: Designing a novel visible-light-driven heterostructure Ni-ZnO/S-g-C3N4 photocatalyst for coloured pollutant degradation.

Expression of concern for 'Designing a novel visible-light-driven heterostructure Ni-ZnO/S-g-C3N4 photocatalyst for coloured pollutant degradation' by Ali Bahadur et al., RSC Adv., 2021, 11, 36518-36527, https://doi.org/10.1039/d0ra09390d.

Expression of concern: Engineering the optical properties of nickel sulphide thin films by zinc integration for photovoltaic applications.

Expression of concern for 'Engineering the optical properties of nickel sulphide thin films by zinc integration for photovoltaic applications' by Junaid Younus et al., RSC Adv., 2023, 13, 27415-27422, https://doi.org/10.1039/D3RA04011A.

Expression of Concern: Construction of a binary S-scheme S-g-C3N4/Co-ZF heterojunction with enhanced spatial charge separation for sunlight-driven photocatalytic performance.

Expression of Concern for 'Construction of a binary S-scheme S-g-C3N4/Co-ZF heterojunction with enhanced spatial charge separation for sunlight-driven photocatalytic performance' by Ali Bahadur et al., RSC Adv., 2022, 12, 23263-23273, https://doi.org/10.1039/D1RA08525E.

Enhanced photocatalytic activity of Bi2MoO6/CdS/Ni ternary heterojunction: Role of Mott Schottky barrier and 2D-2D nanostructure for superior photodegradation of 2-aminophenol.

A unique heterojunction combining Bi2MoO6/CdS with Ni nanoparticles has been synthesized using the solvothermal method. This novel heterojunction, composed of NSs and NRs, was characterized using XRD, Raman, SEM, TEM, STEM, EDX, XPS, UV, and PL techniques. The synthesized heterojunctions exhibited substantial photocatalytic activity towards the degradation of 2-aminophenol, significantly outperforming their single-metal counterparts. The photocatalytic efficiency of the tripartite sheet and rod composite was about 26 and 16 times higher than that of the separate CdS sheets and rods for the reduction of 2-aminophenol. The primary reactive species for photocatalytic degradation were identified as the holes of Bi2MoO6 and the electrons of CdS. The Mott Schottky barrier established between CdS and Ni nanoparticles prevents the transfer of electrons from Ni nanoparticles back to CdS, allowing Ni nanoparticles to efficiently capture electrons and prevent any backward flow. This, in turn, results in enhanced photocatalytic activity. The improved photocatalytic capability is ascribed to the S-scheme heterojunction between Bi2MoO6/CdS, which promotes better separation of electrons and holes. The Mott Schottky barrier between CdS and Ni also ensures a more abundant electron supply for chemical reactions, minimizing potential losses. The 2D-2D nanostructure morphology of Bi2MoO6 and CdS extends the surface area, enhancing light utilization and providing more active reaction sites. The synthesized heterojunction demonstrated impressive stability over three cycles, highlighting its potential for recycling and repeated use.

Fabrication of novel vildagliptin loaded ZnO nanoparticles for anti diabetic activity.

Diabetes mellitus (DM) is a rapidly prevailing disease throughout the world that poses boundless risk factors linked to several health problems. Vildagliptin is the standard dipeptidyl peptidase-4 (DPP-4) inhibitor type of medication that is used for the treatment of diabetes anti-hyperglycemic agent (anti-diabetic drug). The current study aimed to synthesize vildagliptin-loaded ZnO NPs for enhanced efficacy in terms of increased retention time minimizing side effects and increased hypoglycemic effects. Herein, Zinc Oxide (ZnO) nanoparticles (NPs) were constructed by precipitation method then the drug vildagliptin was loaded and drug loading efficiency was estimated by the HPLC method. X-ray diffraction analysis (XRD), UV-vis spectroscopy, FT-IR, scanning electron microscope (SEM), and EDX analysis were performed for the characterization of synthesized vildagliptin-loaded ZnO NPs. The UV-visible spectrum shows a distinct peak at 363 nm which confirms the creation of ZnO NPs and SEM showed mono-dispersed sphere-shaped NPs. EDX analysis shows the presence of desired elements along with the elemental composition. The physio-sorption studies, which used adsorption isotherms to assess adsorption capabilities, found that the Freundlich isotherm model explains the data very well and fits best. The maximum adsorption efficiency of 58.83% was obtained. Further, In vitro, anti-diabetic activity was evaluated by determining the α-amylase and DPP IV inhibition activity of the product formed. The formulation gave maximum inhibition of 82.06% and 94.73% of α-amylase and DPP IV respectively. While at 1000 µg/ml concentration with IC50 values of 24.11 µg/per ml and 42.94 µg/ml. The inhibition of α-amylase can be ascribed to the interactive effect of ZnO NPs and vildagliptin.

Solar power conversion: CuI hole transport layer and Ba3NCl3 absorber enable advanced solar cell technology boosting efficiency over 30.

Researchers are becoming more interested in novel barium-nitride-chloride (Ba3NCl3) hybrid perovskite solar cells (HPSCs) due to their remarkable semiconductor properties. An electron transport layer (ETL) built from TiO2 and a hole transport layer (HTL) made of CuI have been studied in Ba3NCl3-based single junction photovoltaic cells in a variety of variations. Through extensive numerical analysis using SCAPS-1D simulation software, we investigated elements such as layer thickness, defect density, doping concentration, interface defect density, carrier concentration, generation, recombination, temperature, series and shunt resistance, open circuit voltage (V OC), short circuit current (J SC), fill factor (FF), and power conversion efficiency (PCE). The study found that the HTL CuI design reached the highest PCE at 30.47% with a V OC of 1.0649 V, a J SC of 38.2609 mA cm-2, and an FF of 74.78%. These findings offer useful data and a practical plan for producing inexpensive, Ba3NCl3-based thin-film solar cells.

Deciphering the Mechanisms and Biotechnological Implications of Nanoparticle Synthesis Through Microbial Consortia.

Nanomaterial synthesis is a growing study area because of its extensive range of uses. Nanoparticles' high surface-to-volume ratio and rapid interaction with various particles make them appealing for diverse applications. Traditional physical and chemical methods for creating metal nanoparticles are becoming outdated because they involve complex manufacturing processes, high energy consumption, and the formation of harmful by-products that pose major dangers to human health and the environment. Therefore, there is an increasing need to find alternative, cost-effective, dependable, biocompatible, and environmentally acceptable ways of producing nanoparticles. The process of synthesizing nanoparticles using microbes has become highly intriguing because of their ability to create nanoparticles of varying sizes, shapes, and compositions, each with unique physicochemical properties. Microbes are commonly used in nanoparticle production because they are easy to work with, can use low-cost materials, such as agricultural waste, are cheap to scale up, and can adsorb and reduce metal ions into nanoparticles through metabolic activities. Biogenic synthesis of nanoparticles provides a clean, nontoxic, ecologically friendly, and sustainable method using renewable ingredients for reducing metals and stabilizing nanoparticles. Nanomaterials produced by bacteria can serve as an effective pollution control method due to their many functional groups that can effectively target contaminants for efficient bioremediation, aiding in environmental cleanup. At the end of the paper, we will discuss the obstacles that hinder the use of biosynthesized nanoparticles and microbial-based nanoparticles. The paper aims to explore the sustainability of microorganisms in the burgeoning field of green nanotechnology.

Biochar/Delonix regia seed gum/chitosan composite as efficient adsorbent for the elimination of phenol from aqueous medium.

In this study, biochar (BC) from Delonix regia pods peel and gum from Delonix regia seed (SG) were prepared, and also biochar/chitosan composite (BCS) and biochar/Delonix regia seed gum/chitosan composite (BCGS) were fabricated for the efficient adsorption of phenol. Various characterization tools such as SEM, TEM, ATR-FTIR, TGA, zeta potential, and textural investigation were studied to examine the features of the synthetized adsorbents, confirming their positive construction. It was fully studied how necessary factors, comprising pH, dose of adsorbent, contact shaking time, initial phenol concentration, and temperature influenced adsorption behavior. An obvious rise of the adsorption capacity from 60.16 to 165.20 mg/g was achieved by the modification of biochar with Delonix regia seed gum and chitosan under ideal circumstances of 2 h contact duration, pH 7, 15 °C, and a dose of 2.0 g/L. The phenol adsorption was well applied by Langmuir, Temkin, Dubinin-Radushkevich, and Sips isotherms, in addition to nonlinear pseudo-second-order kinetic model. Furthermore, the physisorption, endothermic, and spontaneous process was illustrated by thermodynamic investigation. Additionally, the fabricated adsorbents could be effectively used and regenerated without main losses of only 7.5, 4.6, and 4.0 % for BC, BCS, and BCGS, respectively in the removal percentage after seven cycles of application.

Adsorption and bacterial performance of Nd2O3 modified Ag nanoparticles with enhanced degradation of methylene blue.

Our study focused on the optical behavior, methylene blue (MB) dye degradation potential, antibacterial performance, and silver and trioxide mineral interaction with different bacterial species. We found that the addition of silver nanoparticles (Ag NPs) to neodymium oxide (Nd2O3) resulted in a significant response, with an enlargement of the inhibition zone for bacterial species such as Staphylococcus aureus and Escherichia coli. Specifically, the inhibition zone for S. aureus increased from 9.3 ± 0.5 mm for pure Nd2O3 to 16.7 ± 0.4 mm for the Ag/Nd2O3 nano-composite, while for E. coli, it increased from 8.8 ± 0.4 mm for Nd2O3 to 15.9 ± 0.3 mm for Ag/Nd2O3. Furthermore, the optical behavior of the composites showed a clear band-gap narrowing with the addition of Ag NPs, resulting in enhanced electronic localization. The direct and indirect transitions reduced from 6.7 to 6.1 eV and from 5.2 to 2.9 eV, respectively. Overall, these results suggest that the Ag/Nd2O3 nano-composite has potential applications in sensor industries and water treatment, thanks to its enhanced optical behavior, antibacterial performance, and efficient MB degradation capabilities. In terms of MB degradation, the Ag/Nd2O3 mixed system exhibited more efficient degradation compared to pure Nd2O3. After 150 min, the MB concentration in the mixed system decreased to almost half of its starting point, while pure Nd2O3 only reached 33%.

Synthesis, Glucosidase Inhibition, and In Silico Modeling Analysis of Highly Fluorinated 2-Imino-1,3-thiazolines in Search of Potent Antidiabetic Agents.

In the present work, 2-imino-1,3-thiazolines featuring highly fluorinated fragments were synthesized through a straightforward cyclization of diversely substituted thioureas with 2-bromo-1-(4-fluorophenyl)ethan-1-one. The target compounds were obtained in good yields, and structures were established by FTIR and 1H- and 13C NMR spectroscopic methods. The in vitro biological assay revealed that all the compounds significantly obstruct the α-glucosidase. Compound 6d (3-fluoro-N-(3-(2-fluorophenyl)-4-(4-fluorophenyl)thiazol-2(3H)-ylidene)benzamide) showed the highest antidiabetic potential with an IC50 value of 1.47 ± 0.05 µM. In addition, computational analysis revealed the binding energy of -11.1 kcal/mol for 6d which was lower than the positive standard, acarbose (-7.9 kcal/mol). Several intermolecular interactions between the active site residues and 6d highlight the significance of 2-imino-1,3-thiazoline core in attaining the potent efficacy and making these compounds a valuable pharmacophore in drug discovery.

Evaluation of a novel composite of expanded polystyrene with rGO and SEBS-g-MA.

This study displays the effect of reduced graphene oxide (rGO) nanofiller and polystyrene-b-poly(ethylene-ran-butylene)-b-polystyrene-grafted maleic anhydride (SEBS-g-MA) on the optical, thermal, and mechanical features of expanded polystyrene (EPS). First, the thin films of pristine EPS and composites were prepared using solution cast method. The prepared films were subjected to fourier-transform infrared (FTIR), SEM, UV-visible spectrophotometer, thermogravimetric analysis/differential scanning calorimetry, and universal testing machine for structural, morphological, optical, thermal, and mechanical characterizations. Optical study revealed a significant increase in refractive index and absorption of composites than EPS. Indirect band-gap energy of EPS (~4.08 eV) was reduced to ~1.61 eV for rGO composite and ~ 2.23 eV for composite composed of rGO and SEBS-g-MA. Thermal analyses presented improvement in characterization temperatures such as T10, T50, Tp, Tm, and Tg of composites, which ultimately lead to the thermal stability of prepared composites than pristine EPS. Stress-strain curves displayed higher yield strength (46.62 MPa), Young's modulus (96.29 MPa), and strain at break (0.54%) for EPS+rGO composite than pure EPS having stress at break (1.01 MPa), Young's modulus (12.44 MPa), and strain at break (0.08%). Moreover, ductility with relatively higher strain at break (0.61%) and lower Young's modulus (79.32 MPa) and yield strength (32.98 MPa) was noticed in EPS+rGO+SEBS-g-MA composite than EPS+rGO composite film. Morphological analysis revealed a change in globular morphology of EPS and inhomogeneous dispersion of rGO in EPS to homogeneously dispersed rGO in EPS matrix without globules owing to the addition of SEBS-g-MA. The increase in compatibility of EPS and rGO due to SEBS-g-MA was also observed in FTIR spectra. RESEARCH HIGHLIGHTS: Here, the solution casting approach was used to create the composite film of EPS and rGO with globules of various sizes. After adding SEBS-g-MA, the shape altered to globular free films exhibiting homogenous dispersion of rGO in EPS matrix. An optical investigation showed that composite materials had a significantly higher refractive index and absorption than EPS. The optical, thermal, and mechanical investigations suggest that the produced composites may be a great substitute for virgin EPS, allowing for a wider range of applications.

Fabrication and characterization of Araucaria gum/calcium alginate composite beads for batch and column adsorption of lead ions.

In this work, we developed five solid adsorbents such as calcium alginate beads (CG), Araucaria gum (AR) extracted from Araucaria heterophylla tree by chemical precipitation procedures, and Araucaria gum/calcium alginate composite beads (CR21, CR12, and CR11) prepared with different calcium alginate: Araucaria gum ratios (2:1, 1:2, and 1:1, respectively). The synthesized solid adsorbents were characterized utilizing TGA, XRD, nitrogen adsorption/desorption analysis, ATR-FTIR, pHPZC, swelling ratio, SEM, and TEM. Through the batch and column adsorption strategies, we evaluated the effect of adsorbent dose, pH, initial Pb (II) concentration, shaking time, bed height, and flow rate. The data of batch technique indicated that CR11 demonstrated a maximum batch adsorption capacity of 149.95 mg/g at 25 °C. Lead ions adsorption was well fitted by pseudo-second order and Elovich according to kinetic studies, in addition to Langmuir and Temkin models based on adsorption isotherm studies onto all the samples. Thermodynamic investigation showed that Pb (II) adsorption process is an endothermic, physical, and spontaneous process. The highest column adsorption capacity (161.1 mg/g) was achieved by CR11 at a bed height of 3 cm, flow rate of 10 mL/min, and initial Pb+2 concentration of 225 mg/L with 68 min as breakthrough time and 180 min as exhaustion time. Yoon-Nelson and Thomas models applied well the breakthrough curves of Pb (II) column adsorption. The maximum column adsorption capacity was decreased by 11.4 % after four column adsorption/desorption processes. Our results revealed that CR11 had an excellent adsorption capacity, fast kinetics, and good selectivity, emphasizing its potential for its applications in water treatment.

Identification of potential inhibitors targeting yellow fever virus helicase through ligand and structure-based computational studies.

Yellow fever is a flavivirus having plus-sensed RNA which encodes a single polyprotein. Host proteases cut this polyprotein into seven nonstructural proteins including a vital NS3 protein. The present study aims to identify the most effective inhibitor against the helicase (NS3) using different advanced ligand and structure-based computational studies. A set of 300 ligands was selected against helicase by chemical structural similarity model, which are similar to S-adenosyl-l-cysteine using infiniSee. This tool screens billions of compounds through a similarity search from in-built chemical spaces (CHEMriya, Galaxi, KnowledgeSpace and REALSpace). The pharmacophore was designed from ligands in the library that showed same features. According to the sequence of ligands, six compounds (29, 87, 99, 116, 148, and 208) were taken for pharmacophore designing against helicase protein. Subsequently, compounds from the library which showed the best pharmacophore shared-features were docked using FlexX functionality of SeeSAR and their optibrium properties were analyzed. Afterward, their ADME was improved by replacing the unfavorable fragments, which resulted in the generation of new compounds. The selected best compounds (301, 302, 303 and 304) were docked using SeeSAR and their pharmacokinetics and toxicological properties were evaluated using SwissADME. The optimal inhibitor for yellow fever helicase was 2-amino-N-(4-(dimethylamino)thiazol-2-yl)-4-methyloxazole-5-carboxamide (302), which exhibits promising potential for drug development.Communicated by Ramaswamy H. Sarma.

Investigation of novel bis-thiadiazole bearing schiff base derivatives as effective inhibitors of thymidine phosphorylase: Synthesis, in vitro bioactivity and molecular docking study.

Thymidine phosphorylase (TP) is an angiogenic enzyme. It is crucial for the development, invasion and metastasis of tumors as well as angiogenesis. In our current research, we examine how structurally changing bis-thiadiazole bearing bis-schiff bases affects their ability to inhibit TP. Through the oxidative cyclization of pyridine-based bis-thiosemicarbazone with iodine, a series of fourteen analogs of bis-thiadiazole-based bis-imines with pyridine moiety were developed. Newly synthesized scaffolds were assessed in vitro for their thymidine phosphorylase inhibitory potential and showed moderate to good inhibition profile. Eleven scaffolds such as 4a-4d,4f-4 h and 4j-4 m were discovered to be more effective than standard drug at inhibiting the thymidine phosphorylase enzyme with IC50 values of 1.16 ± 1.20, 1.77 ± 1.10, 2.48 ± 1.30, 12.54 ± 1.60, 14.63 ± 1.70, 15.53 ± 1.80, 17.47 ± 1.70, 18.98 ± 1.70, 19.53 ± 1.50, 22.73 ± 2.40 and 24.87 ± 2.80 respectively, while remaining three analogs such as 4n, 4i and 4ewere found to be more potent, but they were less potent than the standard drug. All analogs underwent SAR studies based on the pattern of substitutions around the aryl part of the bis-thiadiazole skeleton. The most active analogs in the synthesized series were then molecular docking study performed to investigate their interactions of active part of enzyme. The results showed that remarkable interactions were exhibited by these analogs with the targeted enzymes active sites. Furthermore, to confirm the structure of synthesized analogs by employing spectroscopic tools such as HREI-MS and NMR.

Eco-friendly synthesized nanoparticles as antimicrobial agents: an updated review.

Green synthesis of NPs has gained extensive acceptance as they are reliable, eco-friendly, sustainable, and stable. Chemically synthesized NPs cause lung inflammation, heart problems, liver dysfunction, immune suppression, organ accumulation, and altered metabolism, leading to organ-specific toxicity. NPs synthesized from plants and microbes are biologically safe and cost-effective. These microbes and plant sources can consume and accumulate inorganic metal ions from their adjacent niches, thus synthesizing extracellular and intracellular NPs. These inherent characteristics of biological cells to process and modify inorganic metal ions into NPs have helped explore an area of biochemical analysis. Biological entities or their extracts used in NPs include algae, bacteria, fungi, actinomycetes, viruses, yeasts, and plants, with varying capabilities through the bioreduction of metallic NPs. These biosynthesized NPs have a wide range of pharmaceutical applications, such as tissue engineering, detection of pathogens or proteins, antimicrobial agents, anticancer mediators, vehicles for drug delivery, formulations for functional foods, and identification of pathogens, which can contribute to translational research in medical applications. NPs have various applications in the food and drug packaging industry, agriculture, and environmental remediation.

Engineering the optical properties of nickel sulphide thin films by zinc integration for photovoltaic applications.

Thin films of binary nickel sulphide (NiS) and zinc-doped ternary nickel sulphides (Ni1-xZnxS, where x = 0-1) were effectively produced by the chemical bath deposition method, and their potential use in photovoltaics were investigated. Dopant inclusion did not change the crystal structure of NiS, according to the structural analysis of the synthesized samples. They are appropriate for solar cell applications since the morphological study verified the crack-free deposition. Optical research revealed that the deposited thin films had refractive index (n) ranges between 1.25 and 3.0, extinction coefficient (k) ranges between 0.01 and 0.13, and bandgap values between 2.25 and 2.54 eV. Overall findings indicated that doping is a useful method for modifying the composition, and therefore, the structural and morphological characteristics of NiS thin films, to enhance their optoelectronic behavior.

Pyrimidine-morpholine hybrids as potent druggable therapeutics for Alzheimer's disease: Synthesis, biochemical and in silico analyses.

The identification of effective and druggable cholinesterase inhibitors to treat progressive neurodegenerative Alzheimer's disorder remains a continuous drug discovery hunt. In this perspective, the present study investigates the design and discovery of pyrimidine-morpholine hybrids (5a-l) as potent cholinesterase inhibitors. Palladium-catalyzed Suzuki-Miyaura cross-coupling reaction was employed to introduce the structural diversity on the pyrimidine heterocyclic core. A range of commercially available boronic acids was successfully coupled showing a high functional group tolerance. In vitro cholinesterase inhibitory potential using Ellman's method revealed significantly strong potency. Compound 5h bearing a meta-tolyl substituent at 2-position of pyrimidine ring emerged as a lead candidate against AChE with an inhibitory potency of 0.43 ± 0.42 µM, ∼38-fold stronger value than neostigmine (IC50 = 16.3 ± 1.12 µM). Compound 5h also showed the lead inhibition against BuChE with an IC50 value of 2.5 ± 0.04 µM. The kinetics analysis of 5h revealed the non-competitive mode of inhibition against AChE whereas computational modelling results of potent leads depicted diverse contacts with the binding site amino acid residues. Molecular dynamics simulations revealed the stability of biomolecular system, while, ADME analysis demonstrated druglikeness behaviour of potent compounds. Overall, the investigated pyrimidine-morpholine scaffold presented a remarkable potential to be developed as efficacious anti-Alzheimer's drugs.

Recent developments in natural biopolymer based drug delivery systems.

Targeted delivery of drug molecules to diseased sites is a great challenge in pharmaceutical and biomedical sciences. Fabrication of drug delivery systems (DDS) to target and/or diagnose sick cells is an effective means to achieve good therapeutic results along with a minimal toxicological impact on healthy cells. Biopolymers are becoming an important class of materials owing to their biodegradability, good compatibility, non-toxicity, non-immunogenicity, and long blood circulation time and high drug loading ratio for both macros as well as micro-sized drug molecules. This review summarizes the recent trends in biopolymer-based DDS, forecasting their broad future clinical applications. Cellulose chitosan, starch, silk fibroins, collagen, albumin, gelatin, alginate, agar, proteins and peptides have shown potential applications in DDS. A range of synthetic techniques have been reported to design the DDS and are discussed in the current study which is being successfully employed in ocular, dental, transdermal and intranasal delivery systems. Different formulations of DDS are also overviewed in this review article along with synthesis techniques employed for designing the DDS. The possibility of these biopolymer applications points to a new route for creating unique DDS with enhanced therapeutic qualities for scaling up creative formulations up to the clinical level.