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Core-shell nanoparticles are preferable due to their new and/or improved properties over monometallic nanoparticles. Shell metals are present as a film on the surface of a core metal, which leads to an increase in reactivity of the surface. The synthesis of core-shell nanoparticles using biomolecules is an important strategy to get more activity with less toxicity. The present work was intended to prepare bimetallic nanoparticle preparation by green synthetic method. Aqueous extract of Muntingia calabura flowers was used for the preparation of metal core-shell nanoparticles where flower extract acted as both reducing agent and stabilizing agent. Monometallic gold nanoparticles (AuNPs) and silver nanoparticles (AgNP) were prepared using metal precursors chloroauric acid (HAuCl4) and silver nitrate (AgNO3), respectively. For the preparation of bimetallic core-shell nanoparticles, a shell metal precursor (copper acetate) was added. The obtained nanoparticles were characterized by various instrumental methods including UV–Vis spectrophotometry, TEM and SEM techniques, and EDX spectral analysis. Preliminary antibacterial screening of Au@Cu NP and Ag@Cu NP was performed by disk diffusion assay. TEM and SEM images showed that Au@Cu NPs were spherical whereas Ag@Cu NPs had irregular shapes. The EDX analysis revealed that more Cu was deposited in AuCuNPs than in AgCuNPs. The antibacterial activity assay proved that spherical AuCuNPs were more potent than irregular shaped AgCuNPs.

Biological macromolecules including carbohydrates, proteins, peptides, nucleic acids, and lipids are the biologically derived molecules of high molecular weight with several potential advantages like sustainable production, renewability, biocompatibility, biodegradability, longer blood circulation period, targeting capability, etc. These are abundantly derived/extracted from various natural renewable resources (plants, algae, fungi, microbes, insects, animals, etc.), biotechnological fermentation, and microbiological culture process. Since past few decades, a variety of biological macromolecules-based drug releasing carriers have been reported in various dosage forms like injectables, tablets, capsules, gels, hydrogels, beads, microparticles, nanoparticles, patches and films, fibers, liposomes, transferosomes, scaffolds, etc. The use of biological macromolecules-based drug releasing carriers enhances the pharmacokinetics of loaded drugs with reduced systemic toxicity and immunogenicity. In the current chapter, we focus on the recent advancements in the uses of various biological macromolecules in drug delivery applications.

Chitosan is a natural biopolymer, which is extensively used in the formulation of colon-targeted drug-delivery systems. Chitosan-based systems lead to the release of drugs at the colon region by the subsequent degradation of chitosan. This degradation of chitosan occurs through the lysis of glycosidic bonds by the colonic microflora. Native chitosan and different chitosan derivatives, such as carboxymethyl chitosan, trimethyl chitosan, thiolated chitosan, N-succinyl chitosan, PEGylated chitosan, folic acid-conjugated chitosan, hyaluronic acid-coupled chitosan, etc., have widely been used in colon-targeted systems for the effective delivery of therapeutics.

Alginates (ALGs) are the product of alginic acid, which is a marine-derived naturally occurring polysaccharide having excellent biodegradability and biocompatibility. Since long, ALGs have widely been studied and utilized in many medical and biomedical areas, including drug delivery. For the formulation of various dosage forms, ALGs are commonly used as pharmaceutical excipients in many drug delivery dosage forms. Numerous composite systems based on ALGs have already been explored and exploited to facilitate the releasing of drugs for the therapy of different illnesses. Several inorganic biomaterials, such as carbon nanotube (CNT), montmorillonite (MMT), calcium silicate (CS), β-tricalcium phosphate (β-TCP), and hydroxyapatite (HAp) have already been reinforced into the ALG matrices to enable the long-term and more precise release of different drugs. Additionally, these composites have been formulated to improve desired mechanical behavior. The present chapter provides an extensive overview on the reported researches on the inorganic materials–ALG composite systems for drug releasing.

Herein, a facile scale up and shape variable synthesis of gold nanoparticle (AuNP) and reaction mechanism by natural xanthone derivative (mangiferin) has been reported. Mangiferin (C19H18O11; 1,3,6,7-tetrahydroxyxanthone-C2-β- d -glucoside), a xanthone derivative is isolated from Mangifera indica L. leaves which efficiently reduces Au3+ ions to Au0 and stabilizes the formed AuNP. The structural, optical and plasmonic properties of synthesized AuNP have been investigated through different instrumental techniques like UV–Vis and FTIR spectroscopy, powder XRD, FESEM and TEM analysis. It is observed that variation of the concentration of Au3+ ions and mangiferin has a great effect on controlling size and shape of nanoparticles. The role of reaction temperature is also notable. An interesting observation is that with same concentration ratio of HAuCl4/mangiferin (0.025 mM/0.002%) at the room temperature kidney shaped AuNP is produced, whereas it is spherical at boiling temperature. Moreover, mangiferin allows high scale synthesis of AuNPs (0.025 mM to 10 mM) without changing the particles size and shape. The mechanistic investigation through UV–Vis, FTIR and GCMS analyses reveal the cleavage of glucose unit and oxidation of phenolic OH groups during AuNP formation. Non-toxicity of mangiferin conjugated AuNP on normal human breast cell line (MCF-10A) suggesting its future application as a drug delivery system and other related medicinal purposes.

The paper describes HPLC, UV spectrophotometric and non aqueous titrimetric method for the estimation of poorly water soluble protease inhibitor. Ritonavir in raw material and tablet dosage form. HPLC analysis was carried out in a C18 column using acetonitrile, methanol, and buffer in the ratio 60: 20: 20 (v/v/v) at 240 nm. For the spectrophotometric determination, methanolic solution of Ritonavir was reacted with 3-methyl benzothiazolin-2-one hydrazone (MBTH). The oxidative coupled green coloured chromogen was analysed at 633 nm. Non aqueous titration was carried out using perchloric acid as titrant and the end point was determined using crystal violet as indicator. The three methods were validated and statistically evaluated to correlate the difference between the methods for estimation of Ritonavir in pharmaceutical dosage form.

Two chromatographic methods are developed and validated to estimate Atazanavir Sulfate and Ritonavir in new fixed dosage form, that is, tablet dosage form named Synthivan. The first method is based on HPLC separation of the two drugs on the reversed phase HiQSil C18 column (5 µm, 250 × 4.6 mm) at ambient temperature using an isocratic solvent system consisting of acetonitrile and water in the ratio 52:48 (v/v). Quantification is achieved with a PDA detector at 254 nm at a flow rate of 1.5 mL/min. Linearity of concentrations is found at 60–600 µg/mL and 20–200 µg/mL for Atazanavir sulfate and ritonavir, respectively. The second method is based on HPTLC separation of the two drugs on pre-coated silica gel 60F254 aluminum plates using toluene:methanol:glacial acetic acid:ethyl acetate (7:0.5:1.5:2, v/v/v/v) as solvent system followed by densitometric measurements of their spots at 254 nm. The linearity of the concentration is found to be 30–300 and 10–100 ng/spot for Atazanavir Sulfate and Ritonavir, respect...

To study the effective therapeutic bioavailability of Atazanavir Sulfate (ATV), administered singly or in combination with Ritonavir, a cost effective and rapid method is required. In order to assess an in-depth study, it is primarily thought prudent to develop an effective analytical method for estimation of ATV in marketed dosage forms. The present work is to develop a simple and precise analytical method for in depth evaluation of therapeutic efficacy of ATV. The novelty of the method shows linearity in the concentration range of 10-100 µg/mL at two wavelengths, i.e. 254 nm and 284 nm respectively. The chromatographic system consists of HiQSil C18HS column; an isocratic mobile phase consisted of methanol and tetrahydrofuran (95:5 v/v). The developed method is validated according to ICH guidelines in capsule dosage form. Validation of the developed method shows good result in range, linearity, accuracy and precision. Student’st–test was used to correlate the two methods and applied to raw materials and capsule dosage form.

Background: Ritonavir is a protease inhibitor and mostly used as a booster for increasing the bioavailability of other protease inhibitors like Atazanavir Sulfate and Lopinavir. Aims: Quality assessment of the new dosage form of Ritonavir i.e. tablets is very essential, so two sensitive, simple and precise methods are developed for quantification of Ritonavir in bulk and tablet dosage forms. Materials and Methods: The first method is based on first order derivative method and the second is based on area under curve method. Both the methods are validated according to international conference of harmonization (ICH) guidelines. A stability study of Ritonavir is done in UV - Visible Spectrophotometer under different stress conditions recommended by ICH guidelines. Results: The absorption maximum is found to be 239nm in methanol. The absorption maximum in first method is chosen at 253.2nm, and the linearity is found between 4 - 20 ΅g/ml with coefficient of correlation value 0.9981. In the second method, the range for area under curve selected is 237 - 242nm. The linearity is found between 4 -20 ΅g/ml with coefficient of correlation value 0.9992. Conclusion: The developed methods are validated and found to be simple, rapid, precise and cost-effective. The degradation study in tablet dosage form can be used as a stability indicating assay method.

Improvement of biological activities of medicinal plant in combination with metal nanoparticles is highly appealing. Herein, bio-conjugated AuNP and AgNP have been synthesized at room temperature using leaf extract of Saraca asoca a medicinal plant. Phytochemicals present in aqueous leaf extract of Saraca asoca, are acting as reducing, capping and stabilizing agent. The formation of nanoparticles is confirmed and characterized by different instrumental techniques like UV-visible and IR spectroscopy, SEM, TEM and XRD analysis. Both nanoparticles are spherical, monodisperse and crystalline in nature. Phytochemicals, comprising of functional groups like aliphatic ester C–O–C, alcoholic and phenolic–OH in extract are responsible for reduction of metal precursor and functional groups like N–H or O–H are responsible for capping and stabilization of nanoparticles. Preliminary biological activities like antibacterial, anticancer and anti-diabetic activity of bio-conjugated metal nanoparticles are screened through disc diffusion methods, MTT assay and α-amylase inhibition assay. Both AuNP and AgNP show antibacterial activity (zone inhibition values 9.6 mm and 9.7 mm for E. coli and 7.7 mm and 11 mm for B. subtilis, respectively) and anti-diabetic activity (IC50 1.5 mM and 0.35 mM, respectively) whereas AgNP displays growth inhibition of prostate cancer cell line . CAM assay confirm the biocompatibility of synthesized nanoparticles. Further, both nanoparticles show excellent catalytic activity towards the reduction of 4-nitrophenol (4-NP) using as reducing agent even at very low concentration.

1used in the treatment of human immunodeficiency virus (HIV) Type II infection. ATV is re ported as poorly water soluble and a known substrate for both hepatic metabolizing enzyme Cytochrome 450 (CYP3A) and intestinal drug efflux pump, P-glycoprotein (Pgp) so have low oral bioavailability. 2 So co-administration of small dose of Ritonavir (RTV) is recommended as booster. This new drug is official in IP - 2010, but not included in BP or USP. The reported analytical methods for the determination of ATV are based on high performance liquid chromatography (HPLC) 3-12 in biological samples like blood plasma, biological cells, cerebrospinal fluid (CSF) and blood serum. Stress degradation studies were reported analysed by HPLC and ultraviolet spectrophotometry. 13, 14 The present work was aimed to develop a visible spectrophotometric method, which is simple, sensitive, accurate and cost effective to evaluate the quality of the bulk and pharmaceutical formulations. The novelties of the developed methods are that the reagents used in both the methods are easily available and the mechanisms of reactions of the reagents are already well established. The reactions involved with these reagents are simple, rapid and sensitive. Spectrophotometric methods involve simple instrumentation which is cost effective as compared to other instrumental techniques. The present method involves the determination of ATV, which is a second line drug for treatment of type II HIV infection. Still now, the 2 nd line drugs are available at higher price, than the 1 st line drugs. The high