A novel synthesis of N-acryloyl-tris-(hydroxymethyl)aminomethane (NAT) is described. The polymerization kinetics and transparency of the poly(NAT) gels crosslinked by a crosslinker (CL) e.g. N,N'-methylenebisacrylamide (Bis), i.e. poly(NAT+Bis) polymer, are shown. Poly(NAT+Bis) gradient (4-24%) gels were prepared and found to resolve native proteins according to their size. The exclusion limit of these gels is over 3.times.10.sup.6 Da. This is more than threefold higher than the exclusion limit of the polyacrylamide gradient gel of the same concentration. Therefore poly(NAT+CL) gels are better than polyacrylamide gels for the resolution of large proteins. It was demonstrated that poly(NAT+CL)-polyacrylamide composite gels could be prepared. The poly(NAT+CL) gels were found to be advantageous also for isoelectric focussing in carrier ampholytes or immobilized pH gradients. Poly(NAT+CL) gels are also very good for separation of nucleic acids. The resolution is particularly good in the range between several hundred to 4-5000 base pairs. Under the optimized conditions, DNA molecules of more than 20 kbases can be perfectly resolved.

A monomer, polymers containing the monomer, and the use of the polymer in oilfield flooding is disclosed. The subject monomer is represented by the general formula: ##STR1## wherein: n is an integer from 0 to about 4; m is an integer from 0 to about 6; a is an integer equal to at least 1 except where m is equal to 0, a must equal 0 and where m is equal to 1, a must equal 0 or 1; p is an integer from 2 to about 10; b is an integer equal to at least 1 and is of sufficient magnitude that the ratio b/p is at least 0.2; and q is an integer from 0 to 2. The number of hydroxy groups in the monomer is believed to be critical, and therefore the sum of (a+b) divided by the sum (m+p) should be at least 0.2. The moieties linked to the acrylic nitrogen can be joined to provide a ringed structure.

The present invention relates to injectable compositions comprising biocompatible, swellable, hydrophilic, non-toxic and substantially spherical microspheres microspheres and a biocompatible carrier for use in dermal augmentation. The present invention further relates to methods of dermal augmentation, particularly for the treatment of skin contour deficiencies, using the injectable compositions.

The invention encompasses the treatment of urinary incontinence, gastroesophageal reflux disease and the amelioration of skin wrinkles using biocompatible hydrophilic cationic microparticles and a cell adhesion promoter.

The present invention relates to elastic, hydrophilic and substantially spherical microspheres useful for dermal augmentation and tissue bulking. The invention provides injectable compositions comprising the microspheres and a biocompatible carrier for use in dermal augmentation. The present invention further provides methods of dermal augmentation and tissue bulking, particularly for the treatment of skin contour deficiencies, Gastro-esophageal reflux disease, urinary incontinence, and urinary reflux disease, using the injectable compositions.