My activities in water treatment are focused on the development of unique nanofiltration (NF) membranes and membranes for membrane distillation (MD) membranes with improved performance characteristic. Our novel approach for membrane formation is based on supramolecular chemistry and self assembly of polymer blends and nano particles driven by interfacial forces between the polymers and solvents to form membranes with well defined morphologies. For example by this approach of studying the self assembly properties of polymer blends we developed
A) Novel highly robust oxidant stable and back washable, cleaning in place NF membranes for the treatment of municipal waste for unlimited agricultural use and brackish water streams,
B) Novel super hydrophobic membranes for membrane distillation (MD) for water desalination, and
C) Mosaic NF membranes with selective removal of multivalent ions for municipal waste stream treatment for unlimited agricultural use, and for the treatment of industrial product streams.
With a given combination of polymers and solvents combining phase inversion with polymer –polymer separation of an incompatible polymer blend the morphology of the superhydrophobic lotus leaf was approached (Figure 1a and 1b). The lotus leaf (Fig 1b) has a super hydrophobic water repellant surface that we are trying to copy in order to prepare membranes for distillation with high salt rejection, and water vapor permeability. The contact angles are in our membranes in the super hydrophobic range (> 150o) and the membranes demonstrated promising water permeability and salt rejections in direct contact MD.
We have also used self-assembly of incompatible polymer blends to form mosaics (Schematic shown in 2a) of cationic nano particles in a nano thin selective layer of an anionic polymer (SEM of actual membrane shown Figure 2b). Theses membranes have excellent selectivity between salts and non charged solutes and can for example remove both mono-valent and multivalent salts from food and industrial production streams and the treatment of municipal waste streams.
Based on polymer blends of novel derivatives of engineering polymers and a novel crosslinking method for such polymers we have developed selective thin film coatings on a porous support that gave unique highly robust oxidant stable and back washable, cleaning in place NF membranes. Membranes with these characteristics are not commercially or otherwise available. An example of their performance characteristics, compared to commercially available membrane is given in Table 1. These membranes are being developed for the treatment of municipal waste for unlimited agricultural. Both oxidant stability and backwashing in place are extremely important for achieving a cost effective membrane process for the treatment municipal waste streams because of fouling, and which has not been met by current membranes. Water for agricultural water is extremely important and represents the largest worldwide use of water (~60%) and water stress can be significantly mitigated in many parts of the world if highly cost effective membrane systems can be used for the treatment of municipal waste streams to generate water for unlimited agricultural use.

Publications 2012-2015
Refereed articles in scientific journals:

1. T. Hutter T., Linder C, Heldman E., and Grinberg S. (2012), Interfacial and self-assembly properties of bolaamphiphilic compounds derived from a multifunctional oil, Journal of Colloid and Interface Science, 365( 1), p 53-62,

2. Popov M, Grinberg S, Linder C, Bachar Z, Waner T, Deckelbaum R and Heldman E (2012) Site-directed decapsulation of bolaamphiphilic vesicles with enzymatic cleavable surface groups. J Control Release.160, 306-314

3. Dakwar, G, Abu Hammad I, Popov M, Linder C, Grinberg S, Heldman E, Stepensky D (2012) Delivery of proteins to the brain by bolaamphiphilic nano-sized vesicles. J. Control Release. 160, 315-321

4. Kim T, Afonin K, Viard M, Koyfman A, Sparks S, Heldman E, Grinberg S, Linder C, Blumenthal R and Shapiro B (2013) In silico, in vitro and in vivo studies indicate the potential use of bolaamphiphiles for therapeutic siRNA delivery, Nature Therap Nuc Acids March; 2(3): e80

5. Bekani , Linder, Oren et al (2013) Preparation and Characterization of Thin Film Composite Membranes modified with amine functionalized Cyclodextrins, Journal of Applied Polymer Science, 129 (2), 549-558

6. Bhekani S. Mbuli, Rui W Krause, Visvanathan L. Pillay, Yoram Oren, Charles Linder, Bhekie B. Mamba.(2013) Modification of polyamide thin-film composite membranes with amino-cyclodextrins and diethylamino-cyclodextrins for water desalination" Separation and Purification Technology, 120 (13), 328-340.

7. Kaufman Y, Grinberg S, Linder C, Heldman E, Gilron J, Freger V.(2013) Fusion of bolaamphiphile micelles: a method to prepare stable supported biomimetic membranes. Langmuir. 29(4):1152-1161.

8. Philosof-Mazor L, Dakwar GR, Popov M, Kolusheva S, Shames A, Linder C, Greenberg S, Heldman E, Stepensky D, Jelinek R. (2013) Bolaamphiphilic vesicles encapsulating iron oxide nanoparticles: New vehicles for magnetically targeted drug delivery. Int J Pharm. Apr 24;450(1-2):241-249.

9. Popov M, Abu Hammad I, Bachar T, Grinberg S, Linder C, Stepensky D, Heldman E.(2013) Delivery of analgesic peptides to the brain by nano-sized bolaamphiphilic vesicles made of monolayer membranes. Eur J Pharm Biopharm. 2013 Jun 18.

10. Kaufman, Y., S. Grinberg, C. Linder, E. Heldman, J. Gilron, Y. Shen, M. Kumar, R.G.H Lammertink, and V. Freger (2014). Towards supported bolaamphiphile membranes for water filtration: Roles of lipid and substrate. Journal of Membrane Science 457: 50-61.

11. Yang C., X.M. Li, J. Gilron, D.F. Kong, Y. Yin, Y. Oren, C. Linder, T. He (2014). CF4 plasma-modified superhydrophobic PVDF membranes for direct contact membrane distillation. Journal of Membrane Science 456: 155-161.

12. Stern A., M. Guidotti, E. Shaubi, M. Popov, C. Linder, E. Heldman, S. Grinberg, (2014). Steric environment around acetylcholine head groups of bolaamphiphilic nanovesicles influences the release rate of encapsulated compound”. Int. J. NanoMed, 2014:9(1) 561 – 574.

13. Bhekani S. Mbuli, Edward N. Nxumalo, Sabelo D. Mhlanga, Rui W. Krause, Visvanathan L. P., Y. Oren, C. Linder and B. B. Mamba (2014). Development of antifouling polyamide thin-film composite membranes modified with amino-cyclodextrins and diethylamino-cyclodextrins for water treatment. Journal of Applied Polymer Science, 131:8.

14. Berman P., N. Meiri, L. A. Colnago, T. B. Moraes, C. Linder , O. Levi, Y. Parmet, M. Saunders and Z. Wiesman (2015). Study of liquid-phase molecular packing interactions and morphology of fatty acid methyl esters (biodiesel). Biotechnology for Biofuels, 8:1.

15. Meiri N., P. Berman, L. A. Colnago, T. B. Moraes, C. Linder, Z. Wiesman (in press 2015). Liquid phase characterization of molecular interactions in polyunsaturated and n-fatty acid methyl esters by 1H Low field nuclear magnetic resonance. Biotechnology for Biofuels BBIO-D-15-00113R1

16. Shapiro B., K. Gupta, K. A Afonin, V. Herrero, M. Viard, W. Kasprzak, T. Kim, A. Y Koyfman, A. Puri, M. Stepler, A. Sappe, S. Ginsburg, C. Linder, E. Heldman, R. Blumenthal, (in press 2015). Bolaamphiphiles as Carriers for siRNA Delivery: From Chemical Syntheses to Practical Applications. Journal of Controlled Release

B.Sc. 1964 Brooklyn College of the City University of New York. Chemistry Department
M.Sc. 1968 Brooklyn College of the City University of New York. Organic Physical Chemistry
Ph.D. 1973 Polytechnic Institute of Brooklyn, Polymer Chemistry department