Exhibit 10.58  January 3, 2008  Joel
B. Weinstein 12
Kevin Circle Framingham,
MA  01701  Dear Joel,  We are pleased to invite
you to join us as an employee of BioSphere Medical, Inc. (the Company).  On behalf of the Company, I set forth in this
letter agreement the terms of your offer of at-will employment with the
Company:  1.Employment;
Location; Duties.  You will be employed to serve on a full-time basis as Vice President,
Global Marketing and Sales, and will be based at the Companys headquarters in Rockland,
Massachusetts.  You will be subject to
the supervision of, and shall have such authority as is delegated to you by,
the Chief Executive Officer of the Company. 
Assuming you accept this offer, your employment will begin on January 21,
2008.  These terms of your offer of
at-will employment will become effective on such date.  By accepting employment with the Company, you will be agreeing to
undertake the duties and responsibilities inherent in such position and such
other duties and responsibilities as the Chief Executive Officer shall from
time to time reasonably assign to you. 
You agree to devote your entire business time, attention and energies to
the business and interests of the Company during your employment.  You also agree to abide by the rules,
regulations, instructions, personnel practices and policies of the Company and
any changes therein which may be adopted from time to time by the Company.  2.Compensation.  2.1Base
Salary.  Your initial base salary
will be $250,000, less applicable taxes and withholdings, paid bi-weekly in
accordance with the Companys payroll practices (Base Salary).  Such salary and pay schedule may be adjusted
from time to time, in accordance with normal business practice and in the sole
discretion of the Companys Board of Directors or the Compensation Committee,
as provided in the Compensation Committee Charter.  2.2Bonus.  Subject to the second sentence of this Section 2.2,
you will be eligible to receive an annual bonus in an amount equal to up to 40%
of your then current base salary, to be paid based upon your achievement of
milestones and objectives to be mutually agreed upon annually by you and the
Chief Executive Officer with the oversight of the Compensation Committee of the
Board of Directors, but, in any event, such bonus shall be paid


by March 15 of the
year following the year to which the bonus relates, provided that you remain an
employee of the Company at the time such bonus is paid.  You will first be eligible to receive a bonus
in 2009 for services rendered in 2008.  2.3Other
Benefits. You shall be eligible to participate in all benefit programs that
the Company establishes and generally makes available to its employees, if any,
to the extent that the terms of such programs make you eligible to participate,
including but not limited to the Companys health insurance plan, 401(k) plan,
and policies governing paid time off.  In
addition, you shall be entitled to three (3) weeks paid vacation per year,
subject to the Companys policies and procedures, to be taken at such times as
may be approved by the Companys Chief Executive Officer or his designee.  The Company reserves the right to amend
and/or terminate any plan, benefit, or program at any time with or without
notice or publication.  2.4Stock
Options.  Subject to approval by the
Compensation Committee of the Board of Directors, at the next regularly
scheduled meeting of the Compensation Committee (the Grant Date) you will be
granted, pursuant to the Companys 2006 Stock Incentive Plan (the Plan) an
option to purchase 100,000 shares of Common Stock, $0.01 par value (Common
Stock) of the Company pursuant to the terms and conditions of the Plan and a
stock option agreement issued thereunder, such option to be exercisable at a
price per share equal to the closing price of the Companys Common Stock on the
NASDAQ Stock Market on the Grant Date, such option to vest and become
exercisable, subject to your continued employment, at a rate of 20% of the
total shares underlying the option on the first anniversary of the Grant Date
and as to an additional 20% at the end of each full year thereafter.  2.5Reimbursement
of Expenses.  The Company shall
reimburse you for all reasonable travel, entertainment and other expenses
incurred or paid by you in connection with, or related to, the performance of
your duties, responsibilities or services as an employee of the Company, in
accordance with policies and procedures, and subject to limitations, adopted by
the Company from time to time. 
Notwithstanding the foregoing, (i) the expenses eligible for
reimbursement in any one taxable year may not affect the expenses eligible for
reimbursement in any other taxable year, (ii) such reimbursement must be
made on or before the last day of the year following the year in which the
expenses was incurred, and (iii) the right to reimbursement is not subject
to liquidation or exchange for another benefit.  2.6Tax
Withholding.Any payments
provided for hereunder shall be paid net of any applicable tax withholding
required under federal, state or local law.  3.Termination Upon
or in Anticipation of a Change in Control.  3.1In the
event your at-will employment is terminated by the Company without Cause (as
defined below) in anticipation of, or within twelve months after, a Change in
Control (as defined below), the Company shall continue to pay to you your
salary as in effect on the date of termination and the amount of the annual
bonus paid to you for the fiscal year immediately preceding the date of
termination (payable in annualized monthly installments) and shall, provided
you elect to receive group medical insurance pursuant to the federal COBRA
law,  29 U.S.C. § 1161 et seq.,
provide to you (so long as you are
entitled to COBRA coverage) reimbursement for the share of the premium
for group medical and dental that is paid by the  2


Company for active and
similarly-situated employees who receive the same type of coverage, until the
date 12 months after the date of termination, provided, however, that the
Companys obligation to make the aforesaid payments or provide the aforesaid
benefits shall immediately terminate in the event that you violate the
provisions of Section 4 or Section 5 during such 12 month
period.  The payment to you of the
amounts payable under this Section 3.1 shall be contingent upon your
execution of a release in a form reasonably acceptable to the Company and (ii) shall
constitute your sole remedy in the event of a termination of your employment in
the circumstances set forth in this Section 3.1.  Payments to the Employee under this Section 3.1
shall be bifurcated into two portions, consisting of a portion that does not
constitute nonqualified deferred compensation within the meaning of Section 409A
of the Internal Revenue Code of 1986, as amended (the Code) and a portion
that does constitute nonqualified deferred compensation.  Payments hereunder shall first be made from
the portion that does not consist of nonqualified deferred compensation until
it is exhausted and then shall be made from the portion that does constitute
nonqualified deferred compensation. 
Notwithstanding the foregoing, because the Employee is a specified
employee as defined in Section 409A (a)(3)(B)(i) of the Code, the
commencement of the delivery of any such payments that constitute nonqualified
deferred compensation will be delayed to the date that is 6 months and one day
after the Employees termination of employment (the Earliest Payment Date)
unless payable upon the Employees death. 
Any payments that are delayed pursuant to the preceding sentence shall
be paid on the Earliest Payment Date. 
The determination of whether, and the extent to which, any of the
payments to be made to the Employee hereunder are nonqualified deferred
compensation shall be made after the application of all applicable exclusions
under Treasury Reg. § 1.409A-1(b)(9). 
Any payments that are intended to qualify for the exclusion for
separation pay due to involuntary separation from service set forth in Reg. §
1.409A-1(b)(9)(iii) must be paid no later than the last day of the second
taxable year of the Employee following the taxable year of the Employee in
which the Employees termination of employment occurs.  3.2Cause
shall, for the purposes of Section 3.1, mean (a) your continued
failure to substantially perform your reasonably assigned duties (other than
any such failure resulting from incapacity due to physical or mental illness),
after notice of such failure is received by you from the Board which
specifically identifies the manner in which the Board believes you have not
substantially performed your duties; or (b) your willful engagement in
illegal conduct or gross misconduct which is materially and demonstrably
injurious to the Company.  For purposes
of this Section 3.2, no act or failure to act by you shall be considered willful
unless it is done, or omitted to be done, in bad faith and without reasonable
belief that your action or omission was in the best interests of the Company.  3.3Change
in Control means an event or occurrence set forth in any one or more of
subsections (a) through (d) below (including an event or occurrence
that constitutes a Change in Control under one of such subsections, but is
specifically exempted from another such subsection):  (a)the
acquisition by an individual, entity or group (within the meaning of Section 13(d)(3) or
14(d)(2) of the Securities Exchange Act of 1934, as amended (the Exchange
Act)) (a Person) of beneficial ownership of any capital stock of the Company
if,  3


after such acquisition,
such Person beneficially owns (within the meaning of Rule 13d-3
promulgated under the Exchange Act) 50% or more of either (x) the
then-outstanding shares of common stock of the Company (the Outstanding
Company Common Stock) or (y) the combined voting power of the
then-outstanding securities of the Company entitled to vote generally in the
election of directors (the Outstanding Company Voting Securities); provided,
however, that for purposes of this subsection (a), the following acquisitions
shall not constitute a Change in Control: (i) any acquisition directly
from the Company (excluding an acquisition pursuant to the exercise, conversion
or exchange of any security exercisable for, convertible into or exchangeable
for common stock or voting securities of the Company, unless the Person
exercising, converting or exchanging such security acquired such security
directly from the Company or an underwriter or agent of the Company), (ii) any
acquisition by the Company, (iii) any acquisition by any employee benefit
plan (or related trust) sponsored or maintained by the Company or any
corporation controlled by the Company, or (iv) any acquisition by any
corporation pursuant to a transaction which complies with clauses (i) and (ii) of
subsection (c) of this Section 3.3; or  (b)such
time as the Continuing Directors (as defined below) do not constitute a
majority of the Board (or, if applicable, the Board of Directors of a successor
corporation to the Company), where the term Continuing Director means at any
date a member of the  Board (i) who
was a member of the Board on the date of the execution of this letter agreement
or (ii) who was nominated or elected subsequent to such date by at least a
majority of the directors who were Continuing Directors at the time of such
nomination or election or whose election to the Board was recommended or
endorsed by at least a majority of the directors who were Continuing Directors
at the time of such nomination or election; provided, however,
that there shall be excluded from this clause (ii) any individual whose
initial assumption of office occurred as a result of an actual or threatened
election contest with respect to the election or removal of directors or other
actual or threatened solicitation of proxies or consents, by or on behalf of a
person other than the Board; or  (c)the
consummation of a merger, consolidation, reorganization, recapitalization or
statutory share exchange involving the Company or a sale or other disposition
of all or substantially all of the assets of the Company in one or a series of
transactions (a Business Combination), unless, immediately following such
Business Combination, each of the following two conditions is satisfied: (i) all
or substantially all of the individuals and entities who were the beneficial
owners of the Outstanding Company Common Stock and Outstanding Company Voting
Securities immediately prior to such Business Combination beneficially own,
directly or indirectly, more than 50%
of the then-outstanding shares of common stock and the combined voting power of
the then-outstanding securities entitled to vote generally in the election of
directors, respectively, of the resulting or acquiring corporation in such
Business Combination (which shall include, without limitation, a corporation
which as a result of such transaction owns the Company or substantially all of
the Companys assets either directly or through one or more subsidiaries) (such
resulting or acquiring corporation is referred to herein as the Acquiring
Corporation) in substantially the same proportions as their ownership,
immediately prior to such Business Combination, of the Outstanding Company
Common Stock and Outstanding Company Voting Securities, respectively; and (ii) no
Person (excluding any employee benefit plan (or related trust) maintained or
sponsored by the Company or by the Acquiring Corporation) beneficially owns,
directly or indirectly, 50% or
more of the then  4


outstanding shares of
common stock of the Acquiring Corporation, or of the combined voting power of
the then-outstanding securities of such corporation entitled to vote generally
in the election of directors (except to the extent that such ownership existed
prior to the Business Combination); or  (d)approval
by the stockholders of the Company of a complete liquidation or dissolution of
the Company.  4.Non-Competition
and Non-Solicitation.  4.1Restricted
Activities.  While you are employed
by the Company and for a period of one year after the termination or cessation
of such employment for any reason, you will not directly or indirectly either
alone or in association with others (i) solicit, or assist, directly or
indirectly any person or organization to solicit, any employee of the Company
to leave the employ of the Company, or (ii) solicit for employment, hire
or engage as an independent contractor, or assist, directly or indirectly any
person or organization to solicit for employment, hire or engage as an
independent contractor, any person who was employed by the Company at the time
of the termination or cessation of your employment with the Company; provided,
that this clause (ii) shall not apply to the solicitation, hiring or
engagement of any individual whose employment with the Company has been
terminated for a period of six months or longer.  4.2Extension.  If you violate the provisions of Section 4.1,
you shall continue to be bound by the restrictions set forth in Section 4.1
until a period of one year has expired without any violation of such
provisions.  4.3Interpretation.  If any restriction set forth in Section 4.1
is found by any court of competent jurisdiction to be unenforceable because it
extends for too long a period of time or over too great a range of activities
or in too broad a geographic area, it shall be interpreted to extend only over
the maximum period of time, range of activities or geographic area as to which
it may be enforceable.  4.4Equitable
Remedies.  The restrictions contained
in this Section 4 are necessary for the protection of the business and
goodwill of the Company and are considered by you to be reasonable for such
purpose.  You agree that any breach of
this Section 4 is likely to cause the Company substantial and irrevocable
damage which is difficult to measure. 
Therefore, in the event of any such breach or threatened breach, you
agree that the Company, in addition to such other remedies which may be
available, shall have the right to obtain an injunction from a court
restraining such a breach or threatened breach and the right to specific
performance of the provisions of this Section 4 and you hereby waive the
adequacy of a remedy at law as a defense to such relief.  5.Proprietary
Information and Developments.  5.1Proprietary
Information.  (a)You
agree that all information, whether or not in writing, of a private, secret or
confidential nature concerning the Companys business, business relationships
or financial affairs (collectively, Proprietary Information) is and shall be
the exclusive property  5


of the Company.  By way of illustration, but not limitation,
Proprietary Information may include inventions, products, processes, methods,
techniques, formulas, compositions, compounds, projects, developments, plans,
research data, clinical data, financial data, personnel data, computer
programs, customer and supplier lists, and contacts at or knowledge of
customers or prospective customers of the Company.  You will not disclose any Proprietary
Information to any person or entity other than employees of the Company or use
the same for any purposes other than in the performance of your duties as an
employee of the Company without written approval by an officer of the Company,
either during or after your employment with the Company, unless and until such
Proprietary Information has become public knowledge without fault by you or
unless required by law.  (b)You
agree that all files, letters, memoranda, reports, records, data, sketches,
drawings, laboratory notebooks, program listings, or other written,
photographic, or other tangible material, whether created by you or others,
which shall come into your custody or possession, shall be and are the
exclusive property of the Company to be used by you only in the performance of
your duties for the Company.  All such
materials or copies thereof and all tangible property of the Company in your custody
or possession shall be delivered to the Company, upon the earlier of (i) a
request by the Company or (ii) termination of your employment.  After such delivery, you shall not retain any
such materials or copies thereof or any such tangible property.  (c)You
agree that your obligation not to disclose or to use information and materials
of the types set forth in paragraphs (a) and (b) above, and your
obligation to return materials and tangible property, set forth in
paragraph (b) above, also extends to such types of information,
materials and tangible property of customers of the Company or suppliers to the
Company or other third parties who may have disclosed or entrusted the same to
the Company or to you.  5.2Developments.  (a)You
will make full and prompt disclosure to the Company of all inventions,
improvements, discoveries, methods, developments, software, and works of
authorship, whether patentable or not, which are created, made, conceived or
reduced to practice by you or under your direction or jointly with others
during your employment by the Company, whether or not during normal working
hours or on the premises of the Company (all of which are collectively referred
to in this letter agreement as Developments).  (b)You
agree to assign and do hereby assign to the Company (or any person or entity
designated by the Company) all your right, title and interest in and to all
Developments and all related patents, patent applications, copyrights and
copyright applications.  However, this
paragraph (b) shall not apply to Developments which do not relate to
the business or research and development conducted or planned to be conducted
by the Company at the time such Development is created, made, conceived or
reduced to practice and which are made and conceived by you not during normal
working hours, not on the Companys premises and not using the Companys tools,
devices, equipment or Proprietary Information. 
You understand that, to the extent this letter agreement shall be
construed in accordance with the laws of any state which precludes a requirement
in an employee agreement to assign certain classes of inventions  6


made by an employee, this
paragraph (b) shall be interpreted not to apply to any invention
which a court rules and/or the Company agrees falls within such
classes.  You also hereby waive all
claims to moral rights in any Developments.  (c)You
agree to cooperate fully with the Company, both during and after your
employment with the Company, with respect to the procurement, maintenance and
enforcement of copyrights, patents and other intellectual property rights (both
in the United States and foreign countries) relating to Developments.  You shall sign all papers, including, without
limitation, copyright applications, patent applications, declarations, oaths,
formal assignments, assignments of priority rights, and powers of attorney,
which the Company may deem necessary or desirable in order to protect its
rights and interests in any Development. 
You further agree that if the Company is unable, after reasonable
effort, to secure your signature on any such papers, any executive officer of
the Company shall be entitled to execute any such papers as your agent and
attorney-in-fact, and you hereby irrevocably designate and appoint each executive
officer of the Company as your agent and attorney-in-fact to execute any such
papers on his behalf, and to take any and all actions as the Company may deem
necessary or desirable in order to protect its rights and interests in any
Development, under the conditions described in this sentence.  5.3United
States Government Obligations.  You
acknowledge that the Company from time to time may have agreements with other
parties or with the United States Government, or agencies thereof, which impose
obligations or restrictions on the Company regarding inventions made during the
course of work under such agreements or regarding the confidential nature of
such work.  You agree to be bound by all
such obligations and restrictions which are made known to you and to take all
appropriate action necessary to discharge the obligations of the Company under
such agreements.  5.4Equitable
Remedies.  The restrictions contained
in this Section 5 are necessary for the protection of the business and
goodwill of the Company and are considered by you to be reasonable for such
purpose.  You agree that any breach of
this Section 5 is likely to cause the Company substantial and irrevocable
damage which is difficult to measure. 
Therefore, in the event of any such breach or threatened breach, you
agree that the Company, in addition to such other remedies which may be
available, shall have the right to obtain an injunction from a court
restraining such a breach or threatened breach and the right to specific
performance of the provisions of this Section 5 and you hereby waive the
adequacy of a remedy at law as a defense to such relief.  6.Conflicts.  You represent that you are not bound by any employment contract,
restrictive covenant or other restriction preventing you from entering into
employment with or carrying out your responsibilities for the Company, or which
is in any way inconsistent with the terms of this letter.  7


7.Successors and
Assigns.  This letter agreement shall be binding upon and inure to the benefit of
both parties and their respective successors and assigns, including any
corporation with which, or into which, the Company may be merged or which may
succeed to the Companys assets or business, provided, however, that your
obligations are personal and shall not be assigned by you.  Notwithstanding the foregoing, if the Company
is merged with or into a third party which is engaged in multiple lines of
business, or if a third party engaged in multiple lines of business succeeds to
the Companys assets or business, then for purposes of Section 4.1, the
term Company shall mean and refer to the business of the Company as it
existed immediately prior to such event and as it subsequently develops and not
to the third partys other businesses.  8.At-Will Status,
Authorization to Work and Choice of Law.  This letter shall not be construed as an agreement, either express or
implied, to employ you for any stated term, and shall in no way alter the
Companys policy of employment at will, under which both you and the Company
remain free to terminate the employment relationship, with or without cause, at
any time, with or without notice. 
Similarly, nothing in this letter shall be construed as an agreement,
either express or implied, to pay you any compensation or grant you any benefit
beyond the end of your employment with the Company except as described in Section 3.1.  You agree to provide to the Company, within three days of your hire
date, documentation of your eligibility to work in the United States, as
required by the Immigration Reform and Control Act of 1986.  You may need to obtain a work visa in order
to be eligible to work in the United States. 
If that is the case, your employment with the Company will be conditioned
upon your obtaining a work visa in a timely manner as determined by the
Company.  This letter agreement shall be governed by and construed in accordance
with the laws of the Commonwealth of Massachusetts (without reference to the
conflict of laws provisions thereof). 
Any action, suit or other legal proceeding arising under or relating to
any provision of this letter agreement shall be commenced only in a court of
the Commonwealth of Massachusetts (or, if appropriate, a federal court located
within Massachusetts), and the Company and the Employee each consents to the
jurisdiction of such a court.  The
Company and the Employee each hereby irrevocably waive any right to a trial by
jury in any action, suit or other legal proceeding arising under or relating to
any provision of this letter agreement.  If this letter correctly
sets forth the terms under which the Company will employ you, please sign the
enclosed duplicate of this letter in the space provided below and return it to
me.  9.Section 409A.  Notwithstanding anything else to the contrary in this agreement, to the
extent that any of the payments that may be made hereunder constitute nonqualified
deferred compensation, within the meaning of Section 409A and the
Employee is a  specified employee upon his separation (as defined under Section 409A),
the timing of any such payment following the separation date shall be modified
if, absent such modification, such payment would otherwise be subject to
penalty under Section 409A.  In any
event, the Company makes no  8


representation or warranty and shall have no liability to the Employee
or to any other person if any provisions of this agreement are determined to
constitute nonqualified deferred compensation subject to Section 409A,
but do not satisfy the requirements of that section.  Sincerely,By:
  /s/ Richard J. FaleschiniName: Richard J.
  FaleschiniTitle: President and
  Chief Executive OfficerThe foregoing correctly
  sets forth the terms of myat-will employment by BioSphere Medical, Inc.,including but not limited to Sections 4 and 5 above./s/ Joel B. WeinsteinJoel B. WeinsteinDate Accepted:
  January 4, 2008  9