What is PCR PURIFICATION.PCR PURIFICATION Protocol is designed to purify double stranded DNA fragments from PCR and other enzymatic reactions. Fragments from 100bp to 10kb are purified from primers, nucleotides, polymerases and salts using QIAquick spin columns in a microcentrifuge. Even if distinct bands of the expected size are observed, primer dimers should be removed by PCR PURIFICATION method. In the absence of the PURIFICATION, the proofreading activity of DNA polymerase will degrade the PCR fragments or remove the 3' terminal deoxyadenosine from the vector during ligation reaction.

PURIFICATION is one of the concepts that has many usage in the literature of education system. Often we use this concept with the known sentence "PURIFICATION Precedes Instruction". In this paper, this known sentence is challenged and with the investigation of Koran verses and related interpretations and also from the view of the philosophical discussion of transposition, this precedence is falsified. At the end of paper, we introduce another definition of the concept of PURIFICATION from two points of views which is in line with the integrative thought on education and instruction.

What is gel PURIFICATION of PCR Products?In molecular biology, gel extraction or gel isolation is a technique used to isolate a desired fragment of intact DNA from an agarose gel following agarose gel electrophoresis. After extraction, fragments of interest can be mixed, precipitated, and enzymatically ligated together in several simple steps. This process, usually performed on plasmids, is the basis for rudimentary genetic engineering.

OBJECTIVES: Anti-lymphocyte globulin (ALG) is a polyc1onal anti human lymphocyte surface markers which is produced in rabbits. ALG is one of the potent immunosuppressive agents which is currently used for preventing organ allograft rejection, treatment of aplastic anemia and some autoimmune disorders. ALG causes elimination of human lymphocytes from the peripheral blood circulation, regulation of cytotoxic activities and apoptosis. The goal of this project was urification of ALG by a simple, rapid and inexpensive method, ion exchange chromatography. METHODS: ALG riched serum of immunized rabbit with human lymphocytes was diluted with phosphate-buffered saline (PBS, pH 7.4) in a ratio of 1:1 and precipitated with ammonium sulfate in the final concentration of 50%. The precipitant was rewashed with 50% ammonium sulfate, dialyzed against tris-phosphate pH=8.1 and applied to ion-exchange chromatography on DEAE-Sepharose 6B.ALG riched fraction was eluted with starting buffer; Tris-Phosphate (PH=8.1) and final buffer; Tris-Phosphate containing 50 mM NaCl (PH=8.1). RESULTS: The purity of ALG with high percent purity was confirmed by SDS-PAGE, and efficiency of it by histocompatibility assay. CONCLUSION: This preparation is comparable in purity to those of commercially available standard ALG in the benefit of self sufficiency. The 1/80 dilution of purified ALG can lyse human lymphocytes properly in histocompatibility testing which verifies its high efficiency.

Aim: This study was carried out to investigate the application of different magnetic intensities on the sperm freezing medium.Material and methods: In this experiment, the magnetic field induction of 0, 2000, 4000 and 6000 Gauss was used to determine the optimum intensity during the freeze-thawing process. Semen samples were collected from 10 pieces of 24-week-old Ross 308 broiler chickens using abdominal massage technique. In this study, the experimental treatments were: 1) ordinary diluent, 2) G2000-intensive magnetic diluent, 3) G4000-intensive magnetic diluent, and G6000-intensive magnetic diluent. The used diluent in this study was the Lake diluent. This diluent was mixed with 1% soy lecithin and 5% glycerol, and then on the basis of the experimental treatments, they encountered different magnetic intensities. Diluted sperm was frozen based on each treatment, after cooling in a 0.25 ml straws. After freezing some sperm parameters such as total and progressive motilities, morphology, membrane integrity, MDA production, apoptosis status and mitochondrial activity were evaluated.Results: Results showed that different magnetic fields had no significant effect on total and progressive mobilities, membrane integrity, morphology, lipid peroxidation, acrosome integrity and apoptosis mechanisms of rooster sperm. Just mitochondrial membrane potential in the control group was higher than other groups (60.5%, P<0.05).Conclusion: It seems that exposure of rooster semen cryopreservation media with magnetic field cannot be efficient for quality of sperm after thawing.

Pentaerythritol (PE) is a tetravalent alcohol mainly used in painting (as alkyol resins) and military industries. PE is produced by reaction of acetaldehyde with formaldehyde in aqueous solution containing sodium hydroxide. The byproducts of the reaction are dipentaerythritol, sodium format and different linear and cyclic formals. Since the purpose of this work was the production of PE with high yield and high degree of purity, at first the effect of operating parameters on the production yield was studied and the optimum operating ranges for reaction temperature, reaction time and molar ratio of reactants were determined. In the next step, considering that the applications of PE necessitate high degree of purity, different methods of PURIFICATION such as crystallization, hydrolysis through refluxing hydrochloric acids, adsorption with activated carbon and separation based on solubility difference were investigated. The results indicated that separation based on solubility difference is the most appropriate method and whenever combined with crystallization, can increase the degree of purity of PE up to 99/4 percent

A simple preparative method was developed for PURIFICATION of Tyrosinase from edible mushroom (Agaricus bispora). A homogenized extract of mushroom was first saturated by ammonium sulfate. The desired precipitate was mixed thoroughly with DEAE-Cellulose (DE-52) and washed out to produce melanin free precipitate. The obtained protein solution was dialyzed against running water for 4 hrs, then, concentrated and chromatographed on a DE-52 column. On the basis of the activities assay, the eluted fractions by 150 mM salt solution were selected for further PURIFICATION. The collected fractions were pooled and chromatographed on a Sephadex G-200 column. Polyacrylamide gel electrophoresis (PAGE) of the purified tyrosinase produced a single band right beside the commercial sample obtained from Sigma Company at 128 kDa. The lyophilized form of the purified Tyrosinase had a PURIFICATION degree of 104 and showed strong cresolase and catecholase activities when compared to a commerically available tyrosinase.