2012;**8**(1):90-97. DOI: 10.1166/ jbn.2012.1371

[57] Hintzen F et al. In vivo evaluation of an oral self-microemulsifying drug delivery system (SMEDDS) for leuprorelin. International Journal of Pharmaceutics. 2014;**472**(1):20-26. DOI: 10.1016/j.ijpharm.2014.05.047

[58] Zupančič O et al. Development, in vitro and in vivo evaluation of a self-emulsifying drug delivery system (SEDDS) for oral enoxaparin administration. European Journal of Pharmaceutics and Biopharmaceutics. 2016;**109**:113-121. DOI: 10.1016/j. ejpb.2016.09.013

[59] Lupo N et al. Inhibitory effect of emulsifiers in SEDDS on protease activity: Just an illusion? International Journal of Pharmaceutics. 2017;**526**(1):23-30. DOI: 10.1016/j. ijpharm.2017.04.058

[60] Soltani Y, Goodarzi N, Mahjub R. Preparation and characterization of self nano-emulsifying drug delivery system (SNEDDS) for oral delivery of heparin using hydrophobic complexation by cationic polymer of β-cyclodextrin. Drug Development and Industrial Pharmacy. 2017;**43**(11):1-9. DOI: 10.1080/03639045.2017.1353522

[61] Ma E-L et al. In vitro and in vivo evaluation of a novel oral insulin formulation. Acta Pharmacologica Sinica. 2006;**27**(10):1382-1388. DOI: 10.1111/j.1745-7254.2006.00424.x

[62] Lindmark T, Nikkilä T, Artursson P. Mechanisms of absorption enhancement by medium chain fatty acids in intestinal epithelial Caco-2 cell monolayers. Journal of Pharmacology and Experimental Therapeutics. 1995;**275**(2):958-964

[63] Bhavsar MD, Amiji MM. Polymeric nano- and microparticle technologies for oral gene delivery. Expert Opinion

on Drug Delivery. 2007;**4**(3):197-213. DOI: 10.1517/17425<IP_ADDRESS>

[64] Guliyeva Ü et al. Chitosan microparticles containing plasmid DNA as potential oral gene delivery system. European Journal of Pharmaceutics and Biopharmaceutics. 2006;**62**(1):17-25. DOI: 10.1016/j.ejpb.2005.08.006

[65] Negi LM, Tariq M, Talegaonkar S. Nano scale self-emulsifying oil based carrier system for improved oral bioavailability of camptothecin derivative by P-glycoprotein modulation. Colloids and Surfaces B: Biointerfaces. 2013;**111**:346-353. DOI: 10.1016/j.colsurfb.2013.06.001

[66] Parmar N et al. Study of cosurfactant effect on nanoemulsifying area and development of lercanidipine loaded (SNEDDS) self nanoemulsifying drug delivery system. Colloids and Surfaces B: Biointerfaces. 2011;**86**(2):327-338. DOI: 10.1016/j. colsurfb.2011.04.016

[67] Balakumar K et al. Self emulsifying drug delivery system: Optimization and its prototype for various compositions of oils, surfactants and co-surfactants. Journal of Pharmacy Research. 2013;**6**(5):510-514. DOI: 10.1016/j. jopr.2013.04.031

[68] Khoo S-M et al. Formulation design and bioavailability assessment of lipidic self-emulsifying formulations of halofantrine. International Journal of Pharmaceutics. 1998;**167**(1):155-164. DOI: 10.1016/S0378-5173(98)00054-4

[69] Elnaggar YSR, El-Massik MA, Abdallah OY. Self-nanoemulsifying drug delivery systems of tamoxifen citrate: Design and optimization. International Journal of Pharmaceutics. 2009;**380**(1):133-141. DOI: 10.1016/j. ijpharm.2009.07.015

[70] Bandyopadhyay S, Katare OP, Singh B. Optimized self nano-emulsifying

**65**

*Self-Emulsifying Drug Delivery Systems: Easy to Prepare Multifunctional Vectors for Efficient…*

[77] Akhter MH et al. Formulation and development of CoQ10-loaded s-SNEDDS for enhancement of oral bioavailability. Journal of Pharmaceutical Innovation. 2014;**9**(2):121-131. DOI: 10.1007/

[78] Patel J et al. Formulation and development of self-nanoemulsifying granules of olmesartan medoxomil for bioavailability enhancement. Particulate Science and Technology.

[79] Gumaste SG et al. Development of solid SEDDS, IV: Effect of adsorbed lipid and surfactant on tableting properties and surface structures of different silicates. Pharmaceutical Research. 2013;**30**(12):3170-3185. DOI:

[80] Ito Y et al. Oral solid gentamicin preparation using emulsifier and adsorbent. Journal of Controlled Release. 2005;**105**(1):23-31. DOI: 10.1016/j.jconrel.2005.03.017

[81] Krupa A et al. Preformulation studies on solid self-emulsifying systems in powder form containing magnesium aluminometasilicate as porous carrier. AAPS PharmSciTech. 2015;**16**(3):623-635. DOI: 10.1208/

[82] Weerapol Y et al. Enhanced dissolution and oral bioavailability of nifedipine by spontaneous emulsifying powders: Effect of solid carriers and dietary state. European Journal of Pharmaceutics and Biopharmaceutics. 2015;**91**:25-34. DOI:

[83] Chavan RB, Modi SR, Bansal AK. Role of solid carriers in pharmaceutical performance of solid supersaturable SEDDS of celecoxib. International

2015;**495**(1):374-384. DOI: 10.1016/j.

s12249-014-0247-z

10.1016/j.ejpb.2015.01.011

Journal of Pharmaceutics.

ijpharm.2015.09.011

2014;**32**(3):274-290. DOI: 10.1080/02726351.2013.855686

10.1007/s11095-013-1114-4

s12247-014-9179-0

*DOI: http://dx.doi.org/10.5772/intechopen.88412*

systems of ezetimibe with enhanced bioavailability potential using long chain and medium chain triglycerides. Colloids and Surfaces B: Biointerfaces. 2012;**100**:50-61. DOI: 10.1016/j.

[71] Porter CJH et al. Enhancing

DOI: 10.1016/j.addr.2007.10.014

intestinal drug solubilisation using lipidbased delivery systems. Advanced Drug Delivery Reviews. 2008;**60**(6):673-691.

[72] Larsen AT et al. Oral bioavailability of cinnarizine in dogs: Relation to SNEDDS droplet size, drug solubility and in vitro precipitation. European Journal of Pharmaceutical Sciences. 2013;**48**(1):339-350. DOI: 10.1016/j.

[73] Mustapha O et al. Development of novel cilostazol-loaded solid SNEDDS using a SPG membrane emulsification

characterization and in vivo evaluation. Colloids and Surfaces B: Biointerfaces. 2017;**150**:216-222. DOI: 10.1016/j.

technique: Physicochemical

[74] Tang B et al. Development of solid self-emulsifying drug delivery systems: Preparation techniques and dosage forms. Drug Discovery Today. 2008;**13**(13):606-612. DOI: 10.1016/j.

[75] Mandić J et al. Overview of solidification techniques for selfemulsifying drug delivery systems from industrial perspective.

[76] Sanka K, Suda D, Bakshi V. Optimization of solid-self

10.1016/j.jddst.2016.04.003

International Journal of Pharmaceutics. 2017;**533**(2):335-345. DOI: 10.1016/j.

nanoemulsifying drug delivery system for solubility and release profile of clonazepam using simplex lattice

design. Journal of Drug Delivery Science and Technology. 2016;**33**:114-124. DOI:

colsurfb.2016.11.039

drudis.2008.04.006

ijpharm.2017.05.036

colsurfb.2012.05.019

ejps.2012.11.004

*Self-Emulsifying Drug Delivery Systems: Easy to Prepare Multifunctional Vectors for Efficient… DOI: http://dx.doi.org/10.5772/intechopen.88412*

systems of ezetimibe with enhanced bioavailability potential using long chain and medium chain triglycerides. Colloids and Surfaces B: Biointerfaces. 2012;**100**:50-61. DOI: 10.1016/j. colsurfb.2012.05.019

*Current and Future Aspects of Nanomedicine*

[57] Hintzen F et al. In vivo evaluation of an oral self-microemulsifying drug delivery system (SMEDDS) for leuprorelin. International Journal of Pharmaceutics. 2014;**472**(1):20-26. DOI: on Drug Delivery. 2007;**4**(3):197-213.

microparticles containing plasmid DNA as potential oral gene delivery system. European Journal of Pharmaceutics and Biopharmaceutics. 2006;**62**(1):17-25. DOI: 10.1016/j.ejpb.2005.08.006

[65] Negi LM, Tariq M, Talegaonkar S. Nano scale self-emulsifying oil based carrier system for improved oral bioavailability of camptothecin

modulation. Colloids and Surfaces B: Biointerfaces. 2013;**111**:346-353. DOI: 10.1016/j.colsurfb.2013.06.001

cosurfactant effect on nanoemulsifying area and development of lercanidipine loaded (SNEDDS) self nanoemulsifying

[67] Balakumar K et al. Self emulsifying drug delivery system: Optimization and its prototype for various compositions of oils, surfactants and co-surfactants.

[68] Khoo S-M et al. Formulation design and bioavailability assessment of lipidic self-emulsifying formulations of halofantrine. International Journal of Pharmaceutics. 1998;**167**(1):155-164. DOI: 10.1016/S0378-5173(98)00054-4

[69] Elnaggar YSR, El-Massik MA, Abdallah OY. Self-nanoemulsifying drug delivery systems of tamoxifen citrate: Design and optimization. International Journal of Pharmaceutics. 2009;**380**(1):133-141. DOI: 10.1016/j.

[70] Bandyopadhyay S, Katare OP,

Singh B. Optimized self nano-emulsifying

derivative by P-glycoprotein

[66] Parmar N et al. Study of

drug delivery system. Colloids and Surfaces B: Biointerfaces. 2011;**86**(2):327-338. DOI: 10.1016/j.

Journal of Pharmacy Research. 2013;**6**(5):510-514. DOI: 10.1016/j.

colsurfb.2011.04.016

jopr.2013.04.031

ijpharm.2009.07.015

DOI: 10.1517/17425<IP_ADDRESS>

[64] Guliyeva Ü et al. Chitosan

2012;**8**(1):90-97. DOI: 10.1166/

10.1016/j.ijpharm.2014.05.047

[58] Zupančič O et al. Development, in vitro and in vivo evaluation of a self-emulsifying drug delivery system (SEDDS) for oral enoxaparin administration. European Journal of Pharmaceutics and Biopharmaceutics. 2016;**109**:113-121. DOI: 10.1016/j.

jbn.2012.1371

ejpb.2016.09.013

ijpharm.2017.04.058

[59] Lupo N et al. Inhibitory effect of emulsifiers in SEDDS on protease activity: Just an illusion? International Journal of Pharmaceutics. 2017;**526**(1):23-30. DOI: 10.1016/j.

[60] Soltani Y, Goodarzi N, Mahjub R. Preparation and characterization of self nano-emulsifying drug delivery system (SNEDDS) for oral delivery of heparin using hydrophobic complexation by cationic polymer of β-cyclodextrin. Drug Development and Industrial Pharmacy. 2017;**43**(11):1-9. DOI: 10.1080/03639045.2017.1353522

[61] Ma E-L et al. In vitro and in vivo evaluation of a novel oral insulin formulation. Acta Pharmacologica Sinica. 2006;**27**(10):1382-1388. DOI: 10.1111/j.1745-7254.2006.00424.x

[62] Lindmark T, Nikkilä T, Artursson P.

enhancement by medium chain fatty acids in intestinal epithelial Caco-2 cell monolayers. Journal of Pharmacology and Experimental Therapeutics.

[63] Bhavsar MD, Amiji MM. Polymeric nano- and microparticle technologies for oral gene delivery. Expert Opinion

Mechanisms of absorption

1995;**275**(2):958-964

**64**

[71] Porter CJH et al. Enhancing intestinal drug solubilisation using lipidbased delivery systems. Advanced Drug Delivery Reviews. 2008;**60**(6):673-691. DOI: 10.1016/j.addr.2007.10.014

[72] Larsen AT et al. Oral bioavailability of cinnarizine in dogs: Relation to SNEDDS droplet size, drug solubility and in vitro precipitation. European Journal of Pharmaceutical Sciences. 2013;**48**(1):339-350. DOI: 10.1016/j. ejps.2012.11.004

[73] Mustapha O et al. Development of novel cilostazol-loaded solid SNEDDS using a SPG membrane emulsification technique: Physicochemical characterization and in vivo evaluation. Colloids and Surfaces B: Biointerfaces. 2017;**150**:216-222. DOI: 10.1016/j. colsurfb.2016.11.039

[74] Tang B et al. Development of solid self-emulsifying drug delivery systems: Preparation techniques and dosage forms. Drug Discovery Today. 2008;**13**(13):606-612. DOI: 10.1016/j. drudis.2008.04.006

[75] Mandić J et al. Overview of solidification techniques for selfemulsifying drug delivery systems from industrial perspective. International Journal of Pharmaceutics. 2017;**533**(2):335-345. DOI: 10.1016/j. ijpharm.2017.05.036

[76] Sanka K, Suda D, Bakshi V. Optimization of solid-self nanoemulsifying drug delivery system for solubility and release profile of clonazepam using simplex lattice design. Journal of Drug Delivery Science and Technology. 2016;**33**:114-124. DOI: 10.1016/j.jddst.2016.04.003

[77] Akhter MH et al. Formulation and development of CoQ10-loaded s-SNEDDS for enhancement of oral bioavailability. Journal of Pharmaceutical Innovation. 2014;**9**(2):121-131. DOI: 10.1007/ s12247-014-9179-0

[78] Patel J et al. Formulation and development of self-nanoemulsifying granules of olmesartan medoxomil for bioavailability enhancement. Particulate Science and Technology. 2014;**32**(3):274-290. DOI: 10.1080/02726351.2013.855686

[79] Gumaste SG et al. Development of solid SEDDS, IV: Effect of adsorbed lipid and surfactant on tableting properties and surface structures of different silicates. Pharmaceutical Research. 2013;**30**(12):3170-3185. DOI: 10.1007/s11095-013-1114-4

[80] Ito Y et al. Oral solid gentamicin preparation using emulsifier and adsorbent. Journal of Controlled Release. 2005;**105**(1):23-31. DOI: 10.1016/j.jconrel.2005.03.017

[81] Krupa A et al. Preformulation studies on solid self-emulsifying systems in powder form containing magnesium aluminometasilicate as porous carrier. AAPS PharmSciTech. 2015;**16**(3):623-635. DOI: 10.1208/ s12249-014-0247-z

[82] Weerapol Y et al. Enhanced dissolution and oral bioavailability of nifedipine by spontaneous emulsifying powders: Effect of solid carriers and dietary state. European Journal of Pharmaceutics and Biopharmaceutics. 2015;**91**:25-34. DOI: 10.1016/j.ejpb.2015.01.011

[83] Chavan RB, Modi SR, Bansal AK. Role of solid carriers in pharmaceutical performance of solid supersaturable SEDDS of celecoxib. International Journal of Pharmaceutics. 2015;**495**(1):374-384. DOI: 10.1016/j. ijpharm.2015.09.011

[84] Čerpnjak K et al. Tablets and minitablets prepared from spraydried SMEDDS containing naproxen. International Journal of Pharmaceutics. 2015;**495**(1):336-346. DOI: 10.1016/j. ijpharm.2015.08.099

[85] Li L, Yi T, Lam CW-K. Effects of spray-drying and choice of solid carriers on concentrations of Labrasol® and Transcutol® in solid self-microemulsifying drug delivery systems (SMEDDS). Molecules. 2013;**18**(1):545-560

[86] Tan A, Rao S, Prestidge CA. Transforming lipid-based oral drug delivery systems into solid dosage forms: An overview of solid carriers, physicochemical properties, and biopharmaceutical performance. Pharmaceutical Research. 2013;**30**(12):2993-3017. DOI: 10.1007/ s11095-013-1107-3

[87] Wang Z et al. Analysis of DNA methylation status of the promoter of human telomerase reverse transcriptase in gastric carcinogenesis. Archives of Medical Research. 2010;**41**(1):1-6. DOI: 10.1016/j.arcmed.2009.11.001

[88] Newton M et al. The influence of formulation variables on the properties of pellets containing a self-emulsifying mixture. Journal of Pharmaceutical Sciences. 2001;**90**(8):987-995. DOI: 10.1002/jps.1051

[89] Coviello T et al. Polysaccharide hydrogels for modified release formulations. Journal of Controlled Release. 2007;**119**(1):5-24. DOI: 10.1016/j.jconrel.2007.01.004

[90] Zvonar A, Bolko K, Gašperlin M. Microencapsulation of selfmicroemulsifying systems: Optimization of shell-formation phase and hardening process. International Journal of Pharmaceutics. 2012;**437**(1):294-302. DOI: 10.1016/j. ijpharm.2012.08.013

[91] Franceschinis E et al. Influence of process variables on the properties of simvastatin self-emulsifying granules obtained through high shear wet granulation. Powder Technology. 2015;**274**:173-179. DOI: 10.1016/j. powtec.2015.01.026

[92] Seo A et al. The preparation of agglomerates containing solid dispersions of diazepam by melt agglomeration in a high shear mixer. International Journal of Pharmaceutics. 2003;**259**(1):161-171. DOI: 10.1016/ S0378-5173(03)00228-X

[93] Gupta MK et al. Enhanced drug dissolution and bulk properties of solid dispersions granulated with a surface adsorbent. Pharmaceutical Development and Technology. 2001;**6**(4):563-572. DOI: 10.1081/ PDT-120000294

[94] Gupta S, Chavhan S, Sawant KK. Self-nanoemulsifying drug delivery system for adefovir dipivoxil: Design, characterization, in vitro and ex vivo evaluation. Colloids and Surfaces A: Physicochemical and Engineering Aspects. 2011;**392**(1):145-155. DOI: 10.1016/j.colsurfa.2011.09.048

[95] Agrawal AG, Kumar A, Gide PS. Formulation of solid self-nanoemulsifying drug delivery systems using N-methyl pyrrolidone as cosolvent. Drug Development and Industrial Pharmacy. 2015;**41**(4):594-604. DOI: 10.3109/03639045.2014.886695

[96] Gamal W, Fahmy RH, Mohamed MI. Development of novel amisulprideloaded solid self-nanoemulsifying tablets: Preparation and pharmacokinetic evaluation in rabbits. Drug Development and Industrial Pharmacy. 2017;**43**(9):1539-1547. DOI: 10.1080/03639045.2017.1322608

[97] Velasco MV et al. Flow studies on maltodextrins as directly

**67**

*Self-Emulsifying Drug Delivery Systems: Easy to Prepare Multifunctional Vectors for Efficient…*

*DOI: http://dx.doi.org/10.5772/intechopen.88412*

compressible vehicles. Drug Development and Industrial Pharmacy. 1995;**21**(10):1235-1243. DOI: 10.3109/03639049509026672

[98] Pandey P et al. Formulation and evaluation of herbal effervescent granules incorporated with Martynia Annua extract. Journal of Drug Discovery and Therapeutics.

2013;**1**(5):54-57

*Self-Emulsifying Drug Delivery Systems: Easy to Prepare Multifunctional Vectors for Efficient… DOI: http://dx.doi.org/10.5772/intechopen.88412*

compressible vehicles. Drug Development and Industrial Pharmacy. 1995;**21**(10):1235-1243. DOI: 10.3109/03639049509026672

*Current and Future Aspects of Nanomedicine*

[91] Franceschinis E et al. Influence of process variables on the properties of simvastatin self-emulsifying granules obtained through high shear wet granulation. Powder Technology. 2015;**274**:173-179. DOI: 10.1016/j.

powtec.2015.01.026

S0378-5173(03)00228-X

PDT-120000294

[92] Seo A et al. The preparation of agglomerates containing solid dispersions of diazepam by melt agglomeration in a high shear mixer. International Journal of Pharmaceutics. 2003;**259**(1):161-171. DOI: 10.1016/

[93] Gupta MK et al. Enhanced drug dissolution and bulk properties of solid dispersions granulated with a surface adsorbent. Pharmaceutical Development and Technology. 2001;**6**(4):563-572. DOI: 10.1081/

[94] Gupta S, Chavhan S, Sawant KK. Self-nanoemulsifying drug delivery system for adefovir dipivoxil: Design, characterization, in vitro and ex vivo evaluation. Colloids and Surfaces A: Physicochemical and Engineering Aspects. 2011;**392**(1):145-155. DOI: 10.1016/j.colsurfa.2011.09.048

[95] Agrawal AG, Kumar A, Gide PS. Formulation of solid self-nanoemulsifying drug delivery systems using N-methyl pyrrolidone as cosolvent. Drug Development and Industrial

tablets: Preparation and

Pharmacy. 2015;**41**(4):594-604. DOI: 10.3109/03639045.2014.886695

[96] Gamal W, Fahmy RH, Mohamed MI. Development of novel amisulprideloaded solid self-nanoemulsifying

pharmacokinetic evaluation in rabbits. Drug Development and Industrial Pharmacy. 2017;**43**(9):1539-1547. DOI: 10.1080/03639045.2017.1322608

[97] Velasco MV et al. Flow studies on maltodextrins as directly

[84] Čerpnjak K et al. Tablets and minitablets prepared from spraydried SMEDDS containing naproxen. International Journal of Pharmaceutics. 2015;**495**(1):336-346. DOI: 10.1016/j.

[85] Li L, Yi T, Lam CW-K. Effects of spray-drying and choice of solid carriers on concentrations of Labrasol® and Transcutol® in solid self-microemulsifying drug delivery systems (SMEDDS). Molecules.

[86] Tan A, Rao S, Prestidge CA. Transforming lipid-based oral drug delivery systems into solid dosage forms: An overview of solid carriers, physicochemical properties, and biopharmaceutical performance. Pharmaceutical Research.

2013;**30**(12):2993-3017. DOI: 10.1007/

[87] Wang Z et al. Analysis of DNA methylation status of the promoter of human telomerase reverse transcriptase in gastric carcinogenesis. Archives of Medical Research. 2010;**41**(1):1-6. DOI:

[88] Newton M et al. The influence of formulation variables on the properties of pellets containing a self-emulsifying mixture. Journal of Pharmaceutical Sciences. 2001;**90**(8):987-995. DOI:

[89] Coviello T et al. Polysaccharide hydrogels for modified release formulations. Journal of Controlled Release. 2007;**119**(1):5-24. DOI: 10.1016/j.jconrel.2007.01.004

[90] Zvonar A, Bolko K, Gašperlin M.

International Journal of Pharmaceutics. 2012;**437**(1):294-302. DOI: 10.1016/j.

Microencapsulation of selfmicroemulsifying systems: Optimization of shell-formation phase and hardening process.

ijpharm.2012.08.013

10.1016/j.arcmed.2009.11.001

ijpharm.2015.08.099

2013;**18**(1):545-560

s11095-013-1107-3

10.1002/jps.1051

**66**

[98] Pandey P et al. Formulation and evaluation of herbal effervescent granules incorporated with Martynia Annua extract. Journal of Drug Discovery and Therapeutics. 2013;**1**(5):54-57

**69**

body.

**1. Introduction**

**Chapter 5**

**Abstract**

Polymers

Nanofibrous Scaffolds for Skin

Tissue Engineering and Wound

*Lucie Bacakova, Julia Pajorova, Marketa Zikmundova,*

*Elena Filova, Petr Mikes, Vera Jencova,*

*Eva Kuzelova Kostakova and Alla Sinica*

Healing Based on Nature-Derived

Nanofibrous scaffolds belong to the most suitable materials for tissue engineering, because they mimic the fibrous component of the natural extracellular matrix. This chapter is focused on the application of nanofibers in skin tissue engineering and wound healing, because the skin is the largest and vitally important organ in the human body. Nanofibrous meshes can serve as substrates for adhesion, growth and differentiation of skin and stem cells, and also as an antimicrobial and moistureretaining barrier. These meshes have been prepared from a wide range of synthetic and nature-derived polymers. This chapter is focused on the use of nature-derived polymers. These polymers have good or limited degradability in the human tissues, which depends on their origin and on the presence of appropriate enzymes in the human tissues. Non-degradable and less-degradable polymers are usually produced in bacteria, fungi, algae, plants or insects, and include, for example, cellulose, dextran, pullulan, alginate, pectin and silk fibroin. Well-degradable polymers are usually components of the extracellular matrix in the human body or at least in other vertebrates, and include collagen, elastin, keratin and hyaluronic acid, although some polymers produced by non-vertebrate organisms, such as chitosan or poly(3-hydroxybutyrate-*co*-3-hydroxyvalerate), are also degradable in the human

**Keywords:** skin replacements, wound dressings, nanofibers, electrospinning, epidermis, dermis, keratinocytes, fibroblasts, stem cells, vascularization,

Nanofibrous scaffolds are one of the most promising materials for skin tissue engineering and wound dressing, because they resemble nanoarchitecture of the native extracellular matrix (for a review, see [1]). Therefore, they can serve as suitable carriers of cells for tissue engineering and also as suitable wound dressings,

which are able to protect the wound from external harmful effects, mainly

cell delivery, drug delivery, regenerative medicine


**Abstract**

In Tanzania, pure grasslands cover is estimated to be 60,381 km2 , about 6.8% of the total land area, and is distributed in different parts. These grasslands are diverse in dominant grass species depending on rainfall, soil type, altitude, and management or grazing system. They support livestock and wildlife distributed in different eco-tomes and habitats of the country. The potential of grasslands for the livelihood of rural people is explicit from the fact that local people depend solely on natural production to satisfy their needs for animal products. Analysis of grazing lands indicated that livestock population, production of meat, and milk from grasslands increased. But the wildlife population, when considered in terms of livestock equivalent units (Large Herbivore Units) showed a declining trend. The contribution of grasslands to the total volume of meat produced in the country showed a declining state, while milk production showed a slight increase. This situation entails a need to evaluate the grasslands of Tanzania to ascertain their potential for supporting people's livestock, wildlife, and livelihood. This study concluded that more research is needed to establish the possibility of grasslands to keep large numbers of grazing herbivores for sustainable livestock and wildlife production.

**Keywords:** grass species, grazing, livestock, Serengeti, Ugalla ecosystem, wildlife