|
Stockholders' deficiency - Stock-based compensation expense (Details 4) (USD $)
|
12 Months Ended | |
|---|---|---|
|
Dec. 31, 2013
|
Dec. 31, 2012
|
|
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | ||
| Allocated share based compensation expense | $ 1,103,209 | $ 272,594 |
|
Research and development
|
||
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | ||
| Allocated share based compensation expense | 522,725 | 196,281 |
|
General and administrative
|
||
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | ||
| Allocated share based compensation expense | $ 580,484 | $ 76,313 |