Surfactants: Pharmaceutical and Medicinal Aspects

Surfactants are amphipathic substances with lyophobic and lyophilic groups and are critical components in pharmaceutical products. Surfactants have several uses in pharmaceuticals, i) for solubilisation of hydrophobic drugs in aqueous media, ii) as components of emulsions ,iii) surfactant self-assembly vehicles for oral and transdermal drug delivery, iv) as plasticizers in semisolid delivery systems, and v) as agents to improve drug absorption and penetration. Non-ionic surfactants such as ethers of fatty alcohols are most commonly used in pharmaceuticals. Cationic surfactants are capable of exerting antibacterial properties by disrupting bacterial cell membranes. In pharmaceutical processing, phospholipid lecithin, bile salts, certain fatty acids and their derivatives have become indispensable since they afford a uniquely effective and eficient mechanism of drug carriage by solubilising the drugs of fatty origin. The antibacterial, antifungal and antiviral activities make biosurfactants relevant molecules for applications in combating many diseases and as therapeutic agents. Biosurfactants have the potential for use as major immunomodulatory molecules, as anti-adhesive biological coating for biomaterials, in vaccines and gene therapy, and they may be incorporated into probiotic preparations to combat urogenetical tract infections and pulmonary immunotherapy. Gemini surfactants are effective potential transfection agents for non-viral gene therapy. Ionic liquids act as secondary surfactants and the use of surfactant/ionic liquid systems should be explored to build speciic properties in the organized medium, and to explore pharmaceutical applications of traditional, biosurfactant and Gemini surfactants

Modeling of soil phosphorus sorption and control of phosphorus pollution with acid mine drainage floc

The study was conducted to investigate and model phosphorus sorption in soils and to study the effectiveness of acid mine drainage (AMD) floc in controlling phosphorus (P) loss to surface runoff from soils. Phosphorus sorption capacity of surface and subsurface horizons of four benchmark soil series - Berks, Huntington, Lindside, and Monongahela - of West Virginia was measured. The soils of these four series were loaded with increasing amounts of P up to 60% of their P retention capacity. Though amount of P released to the solution increased with increase in degree of P saturation, most of the soils did not release considerable amounts of P. Phosphorus sorption capacity of surface and subsurface horizons of these soil series was predicted by using the standard characterization data on the amounts of Fe and Al oxides, pH, organic carbon, clay content, exchangeable Al and Mn, extractable acidity, and basic cations. Various statistical modeling techniques involving variable selection through stepwise ordinary least-squares regression (OLSR), and the principal components regression (PCR) were used for individual soils and for all soils in common. Models developed using the PCR technique performed the best. Use of AMD floc, an Fe and Al rich waste product generated after neutralization of AMD with chemicals like ammonium hydroxide, calcium hydroxide, and sodium hydroxide, in attenuating P in runoff or in soils was examined. AMD floc attenuated more inositol hexaphosphate (IHP)-P, which is a major organic-P form in poultry and swine manure, than it attenuated inorganic-P. Higher retention of IHP-P suggested that soils could receive more organic P than inorganic P. AMD floc did not catalyze the hydrolysis of IHP-P appreciably. Citrate and oxalate, companion anions of inorganic and IHP-P in manures, competed with both inorganic- and IHP-P for sorption sites onto AMD flocs only at low pH. Sorption of inorganic P was more affected by citrate and oxalate than the IHP-P sorption. Citrate impaired P sorption more than did oxalate, but with increase in pH (range 4-9) citrate competed less with P than did oxalate. Incorporation of AMD floc into soils lowered soil-test P, and degree of P saturation levels significantly in four different soils, and increased their P retention capacity. Results of the present study indicate that P retention capacity of the soils can be predicted from the data collected routinely as a part of soil survey or classification program, and AMD floc can be effectively used in controlling loss of P from soil to the water bodies

Absorber Hydraulics Modification for Zero-Foaming of MDEA Solutions

This thesis describes the research carried out to solve the foaming issues in Malaysia LNG Sdn. Bhd. with its Acid Gas Removal Units. The absorber column hydraulics and design is found to be not suitable for usage of MDEA solvents which gives a higher absorption capacity. A thorough study of absorber hydraulics and parametric study on foaming behavior is carried out. Modification for the hydraulics design is calculated and justified to avoid foaming. The report consist of four chapters that cover the introduction of the project, literature review of related topics, project methodology, Project Progresses and finally the conclusion. The introduction part mainly discussed about the background of the study of foaming issue in the acid gas removal unit using MDEA solvent. Objectives and scope of the study is also defined here to specify the area of study. Chapter 2 of the report describes more on the literature review of Hydraulic Limitations, Foaming Tendency, Foaming Stability, Column Hydraulics Design Consideration, Foaming Factor, and Acid Gas Absorber (Tray column) Internal Design. The methodology and project work will be covered in the Chapter 3 of the report. In this part, the procedure identification of the study, and tooVsoftware required is discussed. The methodology consists of work on reviewing design consideration for absorber column, study properties of MDEA solvents and foaming mechanics. The deliverable from this research is to propose design of absorber column with detailed calculation and modeling which is robust from MDEA solvent foaming. Chapter 4 describes the Results and Discussion. Information from the Excel Modeling is made known here and communicated through tables and calculation basis. Finally, the project conclusion is stated in the report together with the references used for research work on this project. I

Pharmaceutical co-crystals - a review

Co-crystallization alters the molecular interactions and composition of pharmaceutical materials, and is considered better alternatives to optimize drug properties. Co-crystals consists of API and a stoichiometric amount of a pharmaceutically acceptable co-crystal former. Pharmaceutical co-crystals are nonionic supramolecular complexes and can be used to address physical property issues such as solubility, stability and bioavailability in pharmaceutical development without changing the chemical composition of the API. Co-crystals can be constructed through several types of interaction, including hydrogen bonding, pi-stacking, and van der Waals forces. Co-crystals High Throughput provides information on relationship between formation and chemical structure of the API and conformer. Factors affecting co-crystal stability are reported and a co-crystal is only expected to form if it is thermodynamically more stable than the crystals of its components. Phase transformations induced during processing/storage affects the mechanisms of conversion of crystalline drugs to co-crystals. Pharmaceutical co-crystals could play a major part in the future of API formulation and can be employed for chiral resolution

Ionic liquids based active pharmaceutical ingredients

Aims: Salt formation of active pharmaceutical ingredients (APIs) improve their aqueous solubility, processing at industrial level, safety aspects and sometimes biological properties. The aim of the present review is to consider ionic liquids (ILs) based active pharmaceutical ingredients (APIs) as an alternative versatile tool in the pharmaceutical industry. Materials and Methods: ILs are the quaternary salts having melting point below 100 oC. The negative side effects of a given API can be treated by delivering it as an ionic liquid in which the counterion neutralizes the unwanted side effects. Ionic liquid form such as APIs pair for dual treatment therapies with synergistic rather than additive results is another approach. Recently, a major emphasis has been placed on ionic liquids as bearers of desired biological activity. In this context, the properties of the Ionic liquids can be tuned by judicious choice of cation(s) and anion(s). Results: Recent developments have shown that Ionic liquids have potential biological applications in drug delivery, particularly as APIs. Some examples of ionic liquids produced as APIs are described from literature which has at least one pharmaceutical active ion with improved biological activity over the precursor ions. The use of ionogels in sensing platforms clearly has several advantages over current technologies. ILs have considerable potential to provide advances in liquid formulation of protein pharmaceuticals. Conclusions: Pharmaceutical ionic liquids could provide another tool in drug development, design and delivery. Ionic liquid salts as APIs eliminate problems associated with the solid-state and exhibit synergistic physical and biological properties.Objetivos: la formación de sales de principios activos farmacéuticos mejora su solubilidad, procesado a nivel industrial, aspectos de seguridad y en ocasiones las propiedades biológicas. El objetivo de la presente revisión es considerar los líquidos iónicos basados en principios activos como una herramienta versatil y alternativa en la industria farmacéutica. Material y Métodos: Los líquidos iónicos son sales cuaternarias con punto de fusión por debajo de 100ºC. Los efectos secundarios negativos asociados a un determinado principio activo pueden ser tratados si se administra como líquido iónico, en el cual el contraión neutraliza los efectos negativos no deseados. Otro enfoque plantea que los resultados de la sinergia sean mejor en tratamientos terapéuticos combinados con la utilización de líquidos iónicos como principio activo en lugar de aquellos en los que se emplean aditivos. Recientemente, se ha manifestado un mayor enfasis en el uso de liquidos iónicos como transportadores de la actividad biológica deseada. En este contextos, las propiedades de los líquidos iónicos pueden modificarse con la elección juiciosa de cation(es) y anio(es). Resultados y Conclusiones: Los líquidos iónicos farmacéuticos pueden proporcionar una herramienta en el desarrollo, diseño y distribución de fármacos. Las sales de líquidos iónicos como principios activos eliminan los problemas asociados a estado sólido y presentan propiedades fisicas y biológicas sinergicas