Condensed Consolidated Balance Sheets (Current Period Unaudited) - USD ($)	Jun. 30, 2015	Sep. 30, 2014
Current assets:
Cash and cash equivalents	$ 17,783,499	$ 23,894,744
Short-term marketable securities	1,942,882
Accounts receivable, net	2,735,033	$ 4,284,051
Inventories, net	5,077,498	3,895,736
Prepaid expenses and other	599,714	523,947
Total current assets	28,138,626	$ 32,598,478
Long-term marketable securities	2,797,788
Property and equipment, net	455,387	$ 360,084
Intangible assets, net	52,830	53,835
Prepaid expenses and other, noncurrent	625,809	766,423
Total assets	32,070,440	33,778,820
Current liabilities:
Accounts payable	1,400,569	830,503
Accrued liabilities	1,099,514	4,087,976
Total current liabilities	2,500,083	4,918,479
Other liabilities, noncurrent	144,688	157,550
Total liabilities	2,644,771	$ 5,076,029
Commitments and contingencies (Note 9)
Stockholders' equity:
Preferred stock, $0.00001 par value; 5,000,000 shares authorized; none issued and outstanding	0	$ 0
Common stock, $0.00001 par value; 50,000,000 shares authorized; 33,226,161and 33,236,489 shares issued and outstanding	332	332
Additional paid-in capital	88,040,202	88,049,125
Accumulated deficit	(58,614,468)	$ (59,346,666)
Accumulated other comprehensive income	(397)
Total stockholders' equity	29,425,669	$ 28,702,791
Total liabilities and stockholders' equity	$ 32,070,440	$ 33,778,820