US 11,655,448 B2
Placenta-derived matrix and methods of preparing and use thereof
Michael Francis, Virginia Beach, VA (US); Silvia Chen, Virginia Beach, VA (US); Erick Breathwaite, Virginia Beach, VA (US); Rudy Rodriguez, Virginia Beach, VA (US); Alan Smith, Virginia Beach, VA (US); Alexander Huber, Virginia Beach, VA (US); and Jung Bok Lee, Virginia Beach, VA (US)
Assigned to LifeNet Health, Virginia Beach, VA (US)
Appl. No. 15/576,954
Filed by LIFENET HEALTH, Virginia Beach, VA (US)
PCT Filed May 27, 2016, PCT No. PCT/US2016/034712
§ 371(c)(1), (2) Date Nov. 27, 2017,
PCT Pub. No. WO2016/196313, PCT Pub. Date Dec. 8, 2016.
Claims priority of provisional application 62/168,397, filed on May 29, 2015.
Prior Publication US 2018/0155678 A1, Jun. 7, 2018
Int. Cl. C12N 5/00 (2006.01); C12N 5/073 (2010.01)
CPC C12N 5/0068 (2013.01) [C12N 5/0605 (2013.01); C12N 2501/11 (2013.01); C12N 2501/113 (2013.01); C12N 2501/115 (2013.01); C12N 2501/119 (2013.01); C12N 2501/305 (2013.01); C12N 2501/31 (2013.01); C12N 2509/00 (2013.01); C12N 2533/52 (2013.01); C12N 2533/54 (2013.01); C12N 2533/90 (2013.01)] 11 Claims
 
1. A method of preparing a hydrogel obtained from a placental tissue, said method comprising
(a) devitalizing a placenta tissue to produce a devitalized placenta tissue,
(b) digesting the devitalized placenta tissue in a digestion solution having a pepsin and hydrochloric acid (HCl) to produce a placenta-derived matrix,
(c) adjusting pH of the placenta-derived matrix from step (b) to a basic pH of 8.0 to 11.0 to irreversibly inactivate the pepsin,
(d) adjusting the pH of the placenta-derived matrix from step (c) to a neutral pH of 7.0 to 7.2 to prepare a first neutralized placenta-derived matrix,
(e) freeze-drying the first neutralized placenta-derived matrix to produce a sponge structure,
(f) dissolving the sponge structure in an acetic acid solvent to form a second placenta-derived matrix,
(g) adjusting the pH of the second placenta-derived matrix from step (f) to a neutral pH of 7.0 to 7.2 to prepare a second neutralized placenta-derived matrix, and
(h) adjusting the temperature of the second neutralized placenta-derived matrix to 36 to 38° C. to produce the hydrogel.