Assume that you set-up an experiment by seeding Human Mesenchymal Stem Cells (hMSC) on the nanofibers. You have 3 groups and 4 characterization techniques after cell seeding. Experiments should be performed 3 times for the same analysis on the same sample. The concentration of the cells is 3x104 cells/cm2 and the volume of cell suspension in each NF is 50L. Each nanofiber is circular with diameter of 12mm. For cell seeding, cell suspension was homogenized

I HAVE THS SOLUTION BUT I DIDNT UNDERSTAND PART B AND PART C HOW DID YOU FIND DILLUTE VALUE IN THIS QUESTIoN

a)

i) Total sample number will be 36

(3 groups * 4 characterization = 12 sample; 3 time of each experiment = 12*3 = 36 samples)

ii) Total sample volume will be 1.8 ml or 1800 ul.

(36 NF*50ul = 1.8 ml)

iii) cell number in each sample= 3.93*104 cells.

12 mm diameter =1.2 cm diameter or 0.6cm radious)

(area of each circular NF= pi*r2 ; so, 22/7*0.6cm2 = 1.13cm2)

3*104 cells/cm2; so, 3*104 cells* 1.13cm2 = 3.93*104 cells / sample or NF

iv) Cell number in total volume = 1.41*106 cells.

(3.93*104 cells / 50 ul * 1.8 ml = 1.41*106 cells)

b) If we consider cell count of 75 in 5 squares of haemocytometer then,

75*2 (dillution factor)*104 cells / ml

so, 1.5*106 cells / ml will be the concentration in original undiluted culture.

* Note - As per my knowledge only four side squares of haemocytometer was considered for cell counting, not five squares. After counting the number of cells in four squares, average was calculated and multiplied with the dillution factor followed by multiplication with 104.

c) Based on my calculation

For each sample, 26.2 ul cell suspension + 23.8 ul medium will be used. (Total 50 ul).

For total sample, 943.2 ul (26.2*36 ul) cell suspension + 856.8 ul (23.8*36 ul) medium will be used. (Total 1.8 ml)