FSL-RFG(Maleimide) FSL construction kit

The FSL-RFG(Maleimide) FSL Construction Kit is for use in creating Function-Spacer-Lipid (FSL) constructs for use in non-covalent cell-surface modification/engineering of cellular membranes, viral particles, liposomes, or other surfaces [1-10]. FSL-RFG(Mal) is one of several FSL constructs with Reactive Functional Groups (RFG); with this construct having maleimide as its Function group. The semi-rigid Spacer in this molecule is constructed via modified hexapeptide unit (Gly-Gly-Ida)2 coupling to both amino groups of ethylenediamine and has been designed to ensure accessibility for target binding/external interactions and proper presentation of functional peptides at a cell or virion surface as well as imparting good solubility to the construct. Electrostatic repulsion forces of spacer’s anionic groups probably favor uniform distribution of the incorporated constructs on the membrane surface [11]. The diacyl phospholipid derived from unsaturated fatty acids is a prerequisite for spontaneous incorporation into cell membranes. This FSL-RFG(Maleimide) FSL Construction Kit cat # 960819-1-R&D (includes a detailed procedure and contains reagents sufficient for one FSL preparation on a milligram scale from cysteine-containing peptides (Figure 1), proteins or any other thiols of biological interest. The effective synthetic approach is based on the well-known Michael nucleophilic addition to maleimides, which react fast and selectively with SH-groups in the pH range 6.5-7.5 producing stable thioether linkages completely stable at physiological conditions [12-15]. The reaction half-life between millimolar concentrations of maleimide and thiol is estimated to be of the order of few seconds [14,15]; but more complex and heavy molecules of biochemical interest interact somewhat slower even when applied in 10-fold excess and durations of at least 2 hours are recommended [16]. The protocol described here is optimized for this kit using FSL-RFG(Mal) with generic peptides and addresses problems which may be encountered if purification of completed FSL constructs is required

Scalar and Spinor Particles with Low Binding Energy in the Strong Stationary Magnetic Field Studied by Means of Two-and Three-Dimensional Models

On the basis of analytic solutions of Schrodinger and Pauli equations for a uniform magnetic field and a single attractive $\delta({\bf r})$-potential the equations for the bound one-active electron states are discussed. It is vary important that ground electron states in the magnetic field essentially different from the analog state of spin-0 particles that binding energy has been intensively studied at more then forty years ago. We show that binding energy equations for spin-1/2 particles can be obtained without using of a well-known language of boundary conditions in the model of $\delta$-potential that has been developed in pioneering works. Obtained equations are used for the analytically calculation of the energy level displacements, which demonstrate nonlinear dependencies on field intensities. It is shown that in a case of the weak intensity a magnetic field indeed plays a stabilizing role in considering systems. However the strong magnetic field shows the opposite action. We are expected that these properties can be of importance for real quantum mechanical fermionic systems in two- and three-dimensional cases.Comment: 18 page

Effects of Vacuum Polarization in Strong Magnetic Fields with an Allowance Made for the Anomalous Magnetic Moments of Particles

Given the anomalous magnetic moments of electrons and positrons in the one-loop approximation, we calculate the exact Lagrangian of an intense constant magnetic field that replaces the Heisenberg-Euler Lagrangian in traditional quantum electrodynamics (QED). We have established that the derived generalization of the Lagrangian is real for arbitrary magnetic fields. In a weak field, the calculated Lagrangian matches the standard Heisenberg-Euler formula. In extremely strong fields, the field dependence of the Lagrangian completely disappears, and the Lagrangian tends to a constant determined by the anomalous magnetic moments of the particles.Comment: 19 pages, 3 figure